clinical research in dentistry

4 NYSDJ • APRIL 2007

EDITORIAL

BY NOW, THE TERM EVIDENCE-BASED DENTISTRY has becomesomething of a cliché, having been bantered around in practicallyevery dental publication and in many of the presentations and forumswe attend. There is no doubt that the development of clinical protocolsthat are based upon meaningful investigations, investigations thatmeet the “gold standard” of fundamental research design and imple-mentation, is a priority on dentistry’s agenda.But this admirable questis fraught with potential problems and challenges, while still holdingout hope of benefits to both the dental practitioner and to our patients.

Identifying areas of clinical practice that merit further investi-gation must rely upon input from clinicians themselves to maxi-mize the benefits to individual patients and/or the profession atlarge. The “so what?” criteria should be met so that measurable dif-ferences that might potentially be found in clinical outcomes—ifthat is what is being investigated—represent a meaningful state-ment that could and should have an impact upon cogent recom-mendations for changes in clinical treatment protocols.

The role of the clinician as an important member of theresearch team now becomes more important than ever.As such, theclinical dentist and dentist researcher/academic and biostatisticianmust have an unprecedented dialogue and relationship.

Dental education on the predoctoral and postdoctoral levelswill also have an opportunity to broaden research design perspec-tives and will be a significant benefit for all of us. While the abilityto critically assess the professional literature found in our peerreviewed publications has always been and will continue to be animportant responsibility of all dentists, editors and editorial

boards, the expectations for clinician participation in small andlarge research projects will undoubtedly be raised.

The National Institute of Dental and Craniofacial Research(NIDCR) has taken a bold and proactive position in forging a newmodel for clinical research in dentistry. Practice-based research net-works (PBRNs) have been utilized in medicine, and this has result-ed in significant clinical protocol changes. Similarly, the PBRNstructure, as envisioned by the NIDCR, is an inclusive concept thatcombines the rigorous standards of academic research with thepractical demands of clinical practice. As such, the NIDCR commit-ted approximately $75 million, over seven years, to three dentalPBRNs. Each PBRN will be mandated to recruit at least 100 generaldental practitioners as participants in the PBRN investigation pro-jects. This unprecedented hybrid structure of clinical investigationrepresents the ultimate meeting of “town and gown” in dentistry.

One of the three dental PBRNs is based in the Northeast andwas awarded to New York University College of Dentistry and TheEMMES Corp. from Rockville, Maryland. It is referred to as thePEARL Network, an abbreviation for Practitioners Engaged inApplied Research and Learning. I am certain we will be hearing agreat deal more about all of these dental PBRNs in the near future.

As the dental profession charts its course of continued excellenceand relevance to the public in this millennium, clinical research willplay a powerful role in the process. Indeed, the rules of engagementhave been profoundly changed.What an exciting time for all of us!

Clinical Research in DentistryEverything is up for change, from research design to treatment protocols.

The times couldn’t be more challenging, or exciting.

D.D.S. M.Sd

NYSDJ • AUGUST/SEPTEMBER 2006 5

NYSDAD i r e c t o r y

OFFICERSSteven Gounardes, President351 87th St., Brooklyn 11209

Stephen B. Gold, President Elect8 Medical Drive, Port Jefferson Station 11776

Michael R. Breault, Vice President 1368 Union St., Schenectady 12308

John Asaro, Secretary-Treasurer2707 Sheridan Drive, Tonawanda 14150

Alfonso J. Perna, Immediate Past PresidentSixth District Dental Society, 55 Oak St.Binghamton, 13905

Roy E. Lasky, Executive Director121 State St., Albany 12207

William R. Calnon, ADA Trustee3220 Chili Ave., Rochester, NY 14624

NY County-Lawrence Bailey215 W. 125th St., New York 10027NY County-Matthew J. Neary501 Madison Ave., Fl. 22, New York 10022NY County-Robert B. Raiber630 Fifth Ave., #1869, New York 101112-Michael L. Cali2003 E. 60th St., #1A, Brooklyn 112342-Craig S. Ratner1011 Richmond Rd., Staten Island 10304-24132-James J. Sconzo1666 Marine Parkway, Brooklyn 112343-Lawrence J. Busino2 Executive Park Dr., Albany 122033-John P. Essepian180 Old Loudon Rd., Latham 121104-Mark A. Bauman157 Lake Ave., Saratoga Springs 128664-Frederick W. Wetzel1556 Union St., Niskayuna 123095-William H. Karp472 S. Salina St., #222, Syracuse 132025-John J. Liang2813 Genessee St., Utica 135016-Robert W. Baker, Jr.412 N. Tioga St., Ithaca 148506-Scott Farrell39 Leroy St., Binghamton 139057-Richard F. Andolina74 Main St., Hornell 14843

7-Andrew G. Vorrasi2005-A Lyell Ave., Rochester 146068- Jeffrey A. Baumler2145 Lancelot Dr., Niagara Falls 143048- Kevin J. Hanley959 Kenmore Ave., Buffalo 14223-31609-Malcolm S. Graham170 Maple Ave., White Plains 106019-David H. Kraushaar6 Woodthrush Drive, W. Nyack 109949- Neil R. Riesner111 Brook St., 3rd Floor, Scarsdale 10583-5149N- Peter M. Blauzvern366 N. Broadway, Jericho 11753-2032N-David J. Miller467 Newbridge Rd., E. Meadow 11554N-Robert M. Peskin601 Franklin Ave., #225, Garden City 11530-5742Q-Chad P. Gehani35-49 82nd St., Jackson Heights 11372Q-Robert L. Shpuntoff28 Beverly Rd., Great Neck 11021S-Paul R. Leary80 Maple Ave., #206, Smithtown 11787S-Steven I. SnyderSuffolk Oral Surgery Associates, 264 Union Ave., Holbrook 11741B-Stephen B. Harrison1668 Williamsbridge Rd., Bronx 10461B-Richard P. Herman20 Squadron Blvd., New City 10956

BOARD OF GOVERNORS

Annual MeetingsJames E. Spencer2 Burlington Pl., Woodcliff Lake, NJ 07671AwardsMark J. Feldman5 Vanad Dr., Roslyn 11576Chemical DependencyRobert J. Herzog16 Parker Ave., Buffalo 14214Dental Benefit ProgramsIan M. LernerOne Hanson Pl., #2900Brooklyn, NY 11243-2907 Dental Health Planning/Hospital DentistryRobert A. Seminara281 Benedict Rd., Staten Island 10304Dental PracticeBrendan P. Dowd6932 Williams Rd., #1900, Niagara Falls 14304Dental Education & LicensureMadeline S. Ginzburg2600 Netherland Ave., #117Riverdale 10463EthicsKevin A. Henner163 Half Hollow Rd., #1Deer Park 11729

Governmental AffairsJoseph R. Caruso40-29 Utopia Pky., Flushing, 11358InsuranceRoland C. Emmanuele4 Hinchcliffe Dr., Newburgh, NY 12550Membership & CommunicationsDeborah A. Pasquale391 Manhattan Ave., Brooklyn 11211-1422New DentistDavid C. Bray18 Leroy St., Binghamton 13905NominationsAlfonsa J. PernaSixth District Dental Society55 Oak St., Binghamton, NY 13905Peer Review & Quality AssuranceRichard Rausch1 Rockefeller Plaza., #2201, New York 10020-2003ReliefAnthony V. Maresca207 Hallock Rd.Stony Brook, NY 11790

COUNCIL CHAIRPERSONSOFFICE121 State StreetAlbany, NY 12207(518) 465-0044(800) 255-2100

Roy E. LaskyExecutive DirectorMargaret Surowka RossiGeneral CounselMichael J. HerrmannAssistant Executive DirectorFinance-AdministrationJudith L. ShubAssistant Executive DirectorHealth AffairsSandra DiNotoDirectorPublic RelationsMary Grates StollManaging EditorBeth M. WanekAssistant Executive Director

NYSDJ • APRIL 2007 5

Foundation to RecognizeGRADUATING DENTISTS

Annual Deans Award aimed at bolstering oralhealth workforce in New York State.

ENSURING A GROWING and sustainable oralhealth workforce is crucial to expanding theavailability of oral health services to all NewYorkers, particularly the underserved and mem-bers of the state’s growing culturally diversecommunities. To help address this critical issue,the New York State Dental Foundation has estab-lished a Deans Award, which will be present-ed annually to graduating students or post-doctoral trainees who have demonstrated anexceptional level of achievement as measuredby the following criteria:● Outstanding academic performance.● A demonstrated commitment to enhancing

and improving the oral health of under-served populations.

● Membership in the American Dental StudentAssociation.Candidates for the NYSDF Deans Award,

valued at $5,000, must be nominated by thedean of each of the following academic dentalinstitutions: Columbia University College ofDental Medicine; New York University Collegeof Dentistry; University at Buffalo School ofDental Medicine; Stony Brook UniversitySchool of Dental Medicine; and the Universityof Rochester Eastman Dental Center. Uponreview by the Foundation Board, the deans'candidates will each be presented with a$5,000 check at their respective commence-ment ceremonies.

“This is such a wonderful opportunity forthe Foundation to partner with the state’s den-tal schools,” said Foundation Chair Edward J.Downes. “At the same time, we are promotingthe value of organized dentistry, making thisnew program a remarkable win-win for every-body involved.”

Winners of the 2007 Deans awards areexpected to be announced soon.


THE BOARD OF TRUSTEES of the New York State Dental Foundationhas approved a request for funding in the amount of $10,000 from theChemung County-Corning Coalition for Water Fluoridation.

The Chemung County-Corning Coalition for Water Fluori-dation is an affiliation of advocates for completion of the 25-milecorridor of municipal water fluoridation from Chemung County toPainted Post. The eastern portion of Chemung County has been flu-oridated since 1953, a system that currently serves 70,000 of the92,000 residents of the county. To the west, Painted Post has fluori-dated since 1976, serving 9,100 residents. In the intervening years,from initial fluoridation to today, many studies have shown thatchildren in the non-fluoridated 25-mile corridor exhibited elevatednumbers of decayed, missing and filled teeth.

Following a decades-long struggle against vitriolic anti-fluori-dationists, public health advocates were able to successfully lobbythe Corning Board of Health and the Corning City Council to agreeto fluoridate the remaining water supply. The one catch was that theChemung County-Corning Coalition for Water Fluoridation wouldhave to come up with $100,000, half of the capital costs to startwater fluoridation, hence, the request for funding from the NewYork State Dental Foundation.

“We were greatly impressed by the level of support garneredfor this project from all possible stakeholders but most notablyfrom the local dental communities,” said Foundation ViceChairman Robert Raiber. By the time the coalition made its appealthe NYSDF, it had already received $11,000 in pledges from indi-

vidual, local dentists; a $2,500 donation from the Steuben CountyDental Society; and a $10,000 donation from the Seventh DistrictDental Society. In addition, the Ferraioli Dental Lecture haspledged $5,000.

Among the NYSDF’s missions is the goal of increasing publicunderstanding of and access to dental services. Clearly, fluorida-tion is an essential aspect of oral health. The Centers for DiseaseControl has called fluoridation one of the 10 greatest public healthachievements of the 20th century. In its “MMWR Weekly,” the CDCnoted:

“Fluoridation of drinking water began in 1945 and in 1999reached an estimated 144 million persons in the United States.Fluoridation safely and inexpensively benefits both children andadults by effectively preventing tooth decay, regardless of socioeco-nomic status or access to care. Fluoridation has played an importantrole in the reductions of tooth decay (40% - 70% in children) and oftooth loss in adults (40% - 60%).”

The Foundation commends the hard work and efforts of theChemung County-Corning Coalition for Water Fluoridation and isthankful for the opportunity to support and assist efforts toimprove the oral health of all New Yorkers.

Foundation Honors EisenbudThe Board of Trustees of the New York State Dental Foundationrecently honored the memory and outstanding achievements of Dr.Leon Eisenbud, with a contribution of $1,000 to a campaign to ren-

FOUNDATION PLEDGES $10,000 for Fluoridation


ovate and rename the dental department at Long Island JewishMedical Center in his honor.

“Dr. Eisenbud,” said Foundation Chair Edward Downes, “willlong be remembered by members of our Board as well as the lead-ership of the New York State Dental Association as the ‘father of themodern dental residency program.’”

In a letter written in the fall of 2002 to NYSDA ExecutiveDirector Roy E. Lasky, Dr. Eisenbud called passage of the PGY-1 leg-islation “a grand achievement”and referred to the State Board examprocess as “archaic and unfair”:

“…I am writing now to congratulate you on this grandachievement, which indeed was only a dream. The substitution of aresidency for the unfair and archaic state board exam is the mostimportant step forward for the profession in my lifetime. I congrat-ulate you because I know the way you guide things through the leg-islative system. I think maybe this would not have happened with-out you.”

“Dr. Eisenbud’s impeccable reputation and his ability toinstruct and inform others without a doubt helped NYSDA in itsefforts to remove the exam requirement in New York State,” Dr.Downes said.

A committee has been formed at Long Island Jewish MedicalCenter to spearhead the campaign to rename the dental departmentin Dr. Eisenbud’s memory. It is the committee’s hope that everybodyin the dental community will do what he or she can to ensure thatDr. Eisenbud’s legacy will be appropriately memorialized. ■

H O N O R I N G

Excellence in Community Service & Corporate Leadership

Save The DateFO U N D AT I O N S O F EXC E L L E N C E

Awards Luncheon

Friday October 12, 2007 12:00 noon to 2:00 p.m.

The St. Regis Two East 55th Street At Fifth Avenue, NYC


A NEW AND EXCITING TREND in dental research is embodied bythe inauguration of three practice-based research networks fundedby the National Institute for Dental and Craniofacial Research, anarm of the National Institutes of Health. One is based in theNorthwest, a second in the Southeast, and the third, closer to home,at the New York University College of Dentistry. This last, thePEARL Network— PEARL stands for Practitioners Engaged inApplied Research and Learning—has since its inception in 2005enrolled more than 100 practitioner-investigators and has eightstudies either underway or in the planning stages.

Practice-based research networks (PBRNs), which have exist-ed in the United States since the 1980s but until recently onlyamong physicians, generate research of immediate relevance to theprofession by combining the expertise of a central academicresearch center with the savvy of the practitioner working “in thetrenches.”The PBRN concept arose from recognition of the fact thatwhile the majority of clinical research is conducted in academichealth centers, only a minority of patients receive their medical ordental care there.

In contrast, in the PBRN model, network participants—clini-cians involved in private practice, who represent 70 percent of theprofession—submit their own ideas for research to a coordinatingacademic center, where NIH-approved protocols are developed andin turn are implemented by these same practitioners. Improvementsin clinical practice traditionally have proceeded in a top-down man-ner: a study begins in a laboratory or academic site and ends at anacademically based faculty practice. The PBRN model seeks to com-plement this process by including the primary means of achieving

the greatest impact in terms of change: the general practitioner.The PBRN model furthermore seeks to make up for the lack of

data available for clinical decision making and to create a mecha-nism for comparing clinical outcomes reported by practitionerswho have decades of experience with findings generated by acade-mic research centers.

Dentists Make Good CandidatesIn terms of the practical implementation of such a model, experi-ence has demonstrated that private-practice dentists and theiroffice staff are uniquely suited to participate in network-basedresearch, for several reasons. They include the following:● The research focus of PBRNs is primarily problem based.● Dentists are trained to be detail oriented and in control of the

office environment.● The essential elements of clinical research are mirrored by the

dentist’s experience with implementing a treatment plan.● Dedicated private-practice staff are familiar with the team

approach to clinical care, which parallels the environmentrequired for research coordination.A typical dental PBRN study may last anywhere from one

month to three years, although most are of six months’ duration. Itis an observational study that addresses a fundamental clinicalquestion: Why we do what we do; and how can we do it better? Allstudies relate to the day-to-day clinical needs of private dentistsand their patients and involve minimal additional work on the partof the practitioner. Current topics under investigation by NYUCDPEARL Network practitioner-investigators, for example, include:

Practice-Based Research Networks A Win-Win for Private-Practice Dentists and the Future of Dentistry

Analia Veitz-Keenan, D.D.S.; Gary S. Berkowitz, D.D.S.; Irene Brandes, D.D.S., P.C.;Kenneth L. Goldberg, D.M.D.; David A. Hamlin, D.M.D.; Robert Margolin, D.D.S.; Kay Oen, D.D.S.

P E R S P E C T I V E S


● Causes of postoperative hypersensitivity in Class I compositerestorations; and

● The effects of partial vs. complete caries removal on patientoutcomes.

Studies in the planning stages deal with:● The effects of endodontic therapy and restoration on tooth

longevity; and● The effects of sealing vs.restoration on caries extending into dentin.

Time Well SpentWhile the individual dentist’s involvement in a PBRN involves asubstantial personal commitment of time and effort, most practi-tioner-investigators regard the rewards of their participation asmore than commensurate. For example:● Participation in cutting-edge research has a positive impact on

the practitioner-investigator’s practice in addition to leadingto improvements in the practice of dentistry.

● The Network practitioner-investigator gains training in themethods and ethics of clinical research from specially trainedNetwork personnel—a “gift that keeps on giving.”

● Network administration assumes the burden of paperworknecessary for study approval and reporting, thereby freeing upthe practitioner-investigator to concentrate on the nuts andbolts of the study.

● The private-practice dentist, who is typically isolated from theresearch environment, enjoys a new collegiality with otherpractitioner-investigators, with a prestigious academic centerand with NIH. The PBRN acts as a link connecting dentaloffices, integrating these offices into a larger organization anduniting practitioners and academic researchers.

● Participation in a Network study helps satisfy the practition-er’s continuing education requirements.

Multiple RewardsMore and more dentists are viewing PBRNs as a means for becom-ing involved with the advancement of the profession by applyingscientific guidelines to generate significant—and practice-applica-ble—clinical data. PBRNs function at the interface betweenresearch and quality improvement. They have the potential to havea substantial impact on dentistry by adding a learning dimensionto the dental practice while improving primary dental care and cre-ating a connected learning community. They provide opportunitiesto address patient-centered issues that previously were neglected.

The ultimate measure of the success of dental PBRNs will betheir ability to influence dentistry, to change clinical procedures onthe basis of objective and reproducible evidence gathered by multi-ple practitioners representing a wide range of patients, clinicalexpertise and office locations. ■

The authors are all practitioner-investigators in the PEARL network and members ofthe PEARL Practitioner Advisory Group. More information on the PEARL Networkis available at http://www.pearlnetwork.org/


THE DENTAL SCHOOL OF COLUMBIA UNIVERSITY officiallyopened on September 27, 1916, with a combined MD/DDS pro-gram. Dr. Joseph Schroff was the first recipient of a dental degreefrom Columbia, in 1922.

Fast forward almost 100 years and we are witness to outstand-ing contributions to the dental profession by the teachers and gradu-ates of what is now Columbia University College of Dental Medicine.The NYSDJ had an opportunity to visit with Ira Lamster,D.D.S.,M.M.Sc.,dean of the College of Dental Medicine.In the interview that follows,Dr.Lamster illuminates Columbia University’s unique approach and com-mitment to dental education, research, clinical training and communi-ty service in an ever-changing and complex health care environment.

Dr. Moskowitz: You have been dean of the Columbia UniversityCollege of Dental Medicine for approximately five years. How areyou enjoying the job?

Dean Lamster: I enjoy my job immensely. I am fortunate towork with a fine faculty, who are intelligent and dedicated. Our den-tal students and postdoctoral students are very bright and motivat-ed. In addition, the College of Dental Medicine is positioned withinthe Columbia University Medical Center, which is a remarkably col-

laborative institution with many outstanding health care scientistsand clinicians in medicine, public health and nursing. Many of ouracademic, research and patient care programs occur in the contextof the health sciences, and that is the best position for a dentalschool to be in. The job of dean has its challenges, and there aremany demands on your time and energy. This is not a job you cando effectively unless you believe in your school.

Dr. Moskowitz: Are there any special challenges for ColumbiaUniversity College of Dental Medicine because of its location in alarge urban area?

Dean Lamster: Being in an urban setting provides challengesand opportunities. The patients we serve are often those who havedifficulty accessing services, and they present with a significant dis-ease burden. On the other hand, there is enormous satisfaction forour trainees when they provide a service that changes a person’s abil-ity to function or smile. In addition, we have a large pediatric den-tistry service, and starting children in the right direction is a majoraccomplishment that can prevent a lifetime of dental problems.

Dr. Moskowitz: Historically, deans of dental schools havebeen somewhat inaccessible or, at least, not terribly visible to theprofession at large. You, however, are very visible in the dental pro-

A CONVERSATION WITH IRA LAMSTERDean of Columbia University College of Dental Medicine talks about challenges and rewards of sitting at the helm of one of America’s premier dental schools.

Elliott M. Moskowitz, D.D.S., M.SdEditor, The New York State Dental Journal

NYSDJ Editor Elliott Moskowitz, left, discusses issues facing dental education with Columbia University College of Dental Medicine Dean Ira Lamster.


fession. You attend dental meetings, on the local, state and nationallevels, scholarly forums and associated social functions. How doesthis visibility and accessibility help you in your role as dean?

Dean Lamster: It is important for a dean of a dental school toacknowledge his or her constituency. At many of the meetings Iattend, I see our faculty and alumni. It is important to be a part ofthese events.As with all of us, by being there, I can demonstrate myfeelings about the importance of an organization or a particularmeeting. I am still involved in research and still have an active NIHgrant. That is a part of my professional life, but demands on mytime are making this difficult to maintain.

Dr. Moskowitz: What is your vision for Columbia in the nextfive years?

Dean Lamster: The Columbia University College of DentalMedicine is uniquely positioned to bridge the gap between medi-cine and dentistry. I appreciate the fact that dentistry is a distinctprofession but with close ties to medicine; therefore, defining ourrole in the health care system is a critical goal for the future. We seeour predoctoral program evolving into training that allows greatertime for electives and for more interactions with medicine andpublic health. We are continuing to expand our offsite clinical careinitiatives, as well as our research initiatives that look at dental andcraniofacial research in the context of health sciences research.

Dr. Moskowitz: What differences do you see in the studentbody at Columbia today as compared to previous eras?

Dean Lamster: Our student body is truly outstanding. Like alldental schools in the United States, Columbia is seeing a large num-ber of applicants.And those accepted are among the finest studentsapplying to dental school. They come to us with a variety of experi-ences prior to entering the college. Many are interested in what wecan think of as nontraditional careers, including academics,research, business—we have a combined DDS/MBA program—and public health/public service—we also have a combinedDDS/MPH program. Further, many of our students understand theimportance of community service and act on those beliefs while atColumbia.

Dr. Moskowitz: Columbia has always been identified withhaving a strong connection to the surrounding community.What isso special about this relationship?

Dean Lamster: This effort is special because it acknowledgesthat the college considers patient care to be an equal mission withtraining and research. Our connection to the surrounding commu-nity formally began in 1996 with formation of the DentCare pro-gram, which focused on delivery of dental services to children inthe community. This was accomplished through the establishmentof small clinics in local schools or through affiliations with com-munity health centers. More recently, we developed the ElderSmileprogram, which focused on the oral health care needs of olderadults. The patient care component of that program includes visitsto what we term prevention sites, often located in senior centers.We

provide both oral hygiene education and screenings for attendees.Individuals in need of services are then referred to a number ofcommunity treatment centers that specialize in providing dentalservices to older adults.

Dr. Moskowitz: What role do your alumni play in the overallworkings of the dental college?

Dean Lamster: The alumni play a very important role. First, asignificant percentage of our full-time, part-time and volunteerfaculty are alumni of the predoctoral and/or postdoctoral pro-grams. Second, the alumni support the school in a variety of waysbesides serving on the faculty. For example, they participate in ourcontinuing education program as lecturers and presenters; theycontribute to our annual fund; and we are soon to announce a newcapital campaign. They have helped the campaign get off to a finestart. In addition, I am continuously impressed with the accom-plishments of our alumni. We have started to feature these individ-uals and their accomplishments in our alumni magazine Primusand our alumni newsletter Primusnotes.

Dr. Moskowitz: What makes Columbia University College ofDental Medicine different from other dental institutions?

Dean Lamster: We have redefined the predoctoral curriculumon the basis of three tenets. First, our dental students take theirbasic science courses with the students at the College of Physiciansand Surgeons. Second, we stress the critical importance of postdoc-toral education, be that a general practice residency or an AEGDprogram or a specialty program. In fact, over the past few years,more than 97% of our students have continued their education.Third, we have made dual-degree training an important part of our

Dental school at Columbia University, in New York City, awarded first dental degreein 1922, six years after it opened.


curriculum. These offerings include DDS/MPH and DDS/MBA pro-grams, as well as a newly introduced DDS/MA in education withour Teacher’s College. This is intended for those interested in anacademic career. We have also just started our first DDS/PhD pro-gram, in Bioinformatics. Similar changes are being introduced intothe postdoctoral/residency programs.

In addition, our place within the Columbia University MedicalCenter makes us one of only a few dental schools that are truly inte-grated into their health sciences campus. As you know, we do nothave our own building, but, rather, we have floors within the MedicalCenter. This promotes collaboration with the medicine, publichealth and nursing programs on a variety of levels.

Dr. Moskowitz: Dental schools tend to be somewhat insularwith respect to other parts of their universities. What is the rela-tionship between the College of Dental Medicine and other collegeswithin Columbia University?

Dean Lamster: That is not the case at Columbia.While we andthe other CUMC schools are physically separated from the 116thStreet campus, we are clearly part of Columbia, and the ties betweenthe campuses continue to grow. For example, one of our facultymembers is the co-chair of the Columbia University DiversityCouncil for the professional schools. Our faculty is also involved inthe new CTSA grants for clinical research funded by NIH; and one ofour junior faculty received a K12 award through that program. Inaddition, we have a robust research program with BiomedicalEngineering, which is located primarily on the 116th Street campus.There are other examples, but you can see the pattern.

Dr. Moskowitz: How are you preparing your predoctoral stu-dents and postdoctoral residents to cope with an increasingly com-plex health care environment?

Dean Lamster: We feel the environment here at the college is

the best teacher. That is, we see dentistry as an integral part of thehealth sciences environment, and our predoctoral students, post-doctoral students and hospital residents learn from the outsetthat they are treating a patient and not just a set of dental prob-lems. We also have developed a “curricular map,” which definesthe four years of the curriculum into basic, behavioral and clini-cal tracks so the students can see how these three components fittogether. There is also time in the curriculum for discussion oflarger issues facing the dental profession, including access to care,dental health care services for older adults and understanding thecurrent role of the profession, as well as the possibilities for thefuture. Just today, I heard a report on our efforts to introducesmoking cessation into the predoctoral program. This programhas made great strides in the past three years, and we believe thatour graduates will incorporate this aspect of primary health careinto their practices.

We are fortunate to attract an excellent group of dental students,postdoctoral students and residents. They are well read and sociallyconscious when they come to us. We try to nurture that attitude.

Dr. Moskowitz: Funding is always a critical issue in privateacademic institutions. How does Columbia manage this situation?

Dean Lamster: The economics of a private dental school arechallenging. We are structured so that we are not too dependent onany one source or revenue. Tuition accounts for only one-third ofour budget, with clinical income accounting for 40%, and 25% iseverything else, including research, extramural programs andfund-raising activities. Each school within Columbia budgets in asimilar manner. We capture all of our income, including tuition,clinic fees and all direct and indirect costs associated with grants.In turn, we pay a “common cost” to both the University and theMedical Center.

Dean Lamster presides over one of regularly scheduled lunch meetings with small groups of second-year predoctoral students. From left: students Helen Park andCharles Yau; Dean Lamster; student Phillip Mann; NYSDJ Editor Elliott Moskowitz.


Dr. Moskowitz: How do you balance allocating resources forscholarly academic matters and clinical areas?

Dean Lamster: This is one of the most challenging parts ofthe job. There are many good ways to spend money—new clinicalfaculty, adding additional research faculty, construction of newfacilities, a new clinic information system, to name a few. I rely onthe faculty, and, in particular, the senior faculty, to help guide thesedecisions. Over the past few years, we have added to the clinical fac-ulty and recruited new research faculty who are engaged in collab-orative research across the Medical Center and the University. Inaddition, we have built new research laboratories and renovatedsome clinical areas.We are now constructing a new faculty practiceon the Medical Center campus. Our next task is to renovate one ofour main clinical floors. So, I guess the response to your question isactually, balance.

Dr. Moskowitz: Where do ethics fit into the curriculum ofyour Columbia students? What special challenges do you see in thisarea?

Dean Lamster: Maintaining ethical standards is a challengefor the professions and for society in general.We recently revampedour ethics program and now include instruction in ethics in all fouryears of the curriculum. In fact, ethical behavior is addressed at ori-entation for the new first-year students and is reinforced duringthat week with the White Coat Ceremony. We have also establishedan Ethics Committee for the College, with representation from thesenior and junior full-time faculty, the part-time faculty and thestudent body.

Dr. Moskowitz: Can you tell me if there are any significantproblems in attracting our younger colleagues to either full-time orpart-time faculty positions? And if so, why?

Dean Lamster: In the past few years, we have increased thefull-time faculty by 10%. For the most part, these have beenrecent graduates who have completed their specialty training orcompleted a general practice residency. They are engaged inteaching, research and clinical care. These are terrific peoplewho are joining the full-time faculty for the right reasons. Theyenjoy teaching and do it well, and are enthusiastic about an aca-demic career. Many, but not all, are Columbians. I believe wehave opened our students’ eyes to the advantages of an academ-ic career, in part by offering dual degree programs—we noweven have a DDS/MA joint degree program with the Teacher’sCollege. I would like to see more young graduates joining thevolunteer faculty.

Dr. Moskowitz: What would be some incentives for motivatingour colleagues to return to their alma mater as either part-time orfull-time faculty?

Dean Lamster: There are many reasons to join the volun-teer faculty. First, as we know, the dental profession is attractingexcellent students. It is rewarding to be involved in their educa-tion. Second, serving on the volunteer faculty provides opportu-

nities for professional interaction that may not be available to thefull-time clinician. Third, it is the right thing to do. Dentalschools need volunteer faculty. Members of our profession haverealized many terrific advantages as a result of their education.We should be giving back so our dental schools remain strongand vibrant

Dr. Moskowitz: Academic institutions and the AmericanDental Association have not always worked harmoniously. How caneach support the other’s efforts?

Dean Lamster: I agree that the dental schools and the ADAhave not always worked well together. If one steps back to examinethe situation, there are many reasons why we should work welltogether. We are educating the future members of the ADA, and wecan do more if we work together to address problems faced by theprofession. We have, however, developed a good working relation-ship with the New York State Dental Association. The four dentalschools in New York—Columbia, NYU, SUNY Buffalo and SUNYStony Brook—along with the Eastman Dental Center at theUniversity of Rochester, a graduate dental institution, work togeth-er on projects of mutual interest through the New York StateAcademic Dental Centers group. We often work with NYSDA, andwe have found that we have common goals. A mutual respect hasdeveloped, and I anticipate that this collaboration will continue toexpand in the future.

Dr. Moskowitz: I want to thank you for allowing The NYSDJ tointerview you. You have provided us with valuable and interestinginsight into the educational mission of Columbia University and thechallenges of being dean of such a unique academic institution. ■

College of Dental Medicine, on 168th Street, is positioned within ColumbiaUniversity Medical Center. Mix of patients seen at College reflects its urban setting.


Abstract

The purpose of this study was to determine the extent of bac-

terial contamination of toothbrushes after use and the efficacy

of chlorhexidine and Listerine in decontaminating tooth-

brushes. The effectiveness of covering a toothbrush head

with a plastic cap in preventing contamination was also eval-

uated. It was found that 70% of the used toothbrushes were

heavily contaminated with different pathogenic microorgan-

isms. Use of a cap leads to growth of opportunistic microor-

ganisms like Pseudomonas aeruginosa, which may cause

infection in the oral cavity. Overnight immersion of a tooth-

brush in chlorhexidine gluconate (0.2%) was found to be

highly effective in preventing such microbial contamination.

THE USE OF ORAL CLEANING INSTRUMENTS, such as a tooth-brush and dental floss, is essential for removing dental plaque, acontributor to dental caries and periodontitis. Although varioustypes of toothbrushes and methods of toothbrushing aredescribed, procedures required for maintaining their cleanlinessare addressed infrequently.

The concept that toothbrushes are contaminated after use was pro-posed as early as 1920 by Cobb,1 who implicated the contaminatedtoothbrush as a cause of repeated infections of the mouth.Microorganisms can gain entry into a toothbrush from the oralcavity or from the external environment, such as contaminated fin-gers, aerosols from toilet flushing and bacteria present in moist,humid conditions found in the bathroom.

Various studies1-6 have reported contamination of toothbrush-es with microorganisms and have recommended methods ofdecontamination. However, no studies have been conducted to findout the effectiveness of covering the toothbrush head with a plastic

cap in reducing/preventing contamina-tion, as claimed by various toothbrushmanufacturers. Also, literature is scarceon the effectiveness of Listerine, a com-monly used mouthwash in decontaminat-ing toothbrushes.

Therefore, the present study was con-ducted to determine the level of contami-nation in used toothbrushes that werekept open and toothbrushes whose headswere covered with a plastic cap (Figure 1).Further, the effectiveness of chlorhexi-dine and Listerine in decontaminatingused toothbrushes was evaluated.

Bacterial Contamination and Decontaminationof Toothbrushes after Use

Abhishek Mehta, B.D.S.; Peter Simon Sequeira, M.D.S.; Gopalkrishna Bhat, Ph.D.

Figure 1. Different tooth-brushes tested for contam-ination.

Material and MethodsFor the present study, the subjects selected were students from ahostel, so the environmental conditions were similar. Students whohad open carious lesions, severe gingivitis and throat infectionswere excluded from the study. Ten individuals, aged 24 to 27, wereselected, and written informed consents were obtained. Twounused toothbrushes (control) were cultured to check for anymicrobial growth in packed toothbrushes before starting the study.

The study was conducted in three phases. In all three phases,each lasting one week, subjects were provided with abrand new toothbrush and were instructed to brushwith it twice daily and rinse it in running tap water forat least 30 seconds. The toothpaste used by all the sub-jects was the same.

In the first phase, subjects were instructed to keeptheir toothbrushes in the open air for drying after use.In the second phase, retrieved brushes were immersedin either a 0.2% solution of chlorhexidine gluconate(ICPA Health Products, India) or Listerine (Pfizer, Ltd., USA)

mouthwash for 12 hours by the investigator.In the third phase, a new toothbrush, whose head

was covered with a plastic cap, was given. Along withthe instructions given in the previous phases, subjectswere told to keep the toothbrush head covered with aplastic cap after every use.

Used toothbrushes were recovered after one weekin each phase and were transported in separate steriletest tubes with a cotton plug for microbiological analy-sis. The handle of the toothbrush was disinfected witha surgical spirit and the head part was immersed in 10ml of phosphate buffered saline (PBS) and vortexed forfive minutes to dislodge the bacteria. Serial 10-folddilutions were made and 10 µl was spread on a bloodagar plate. The inoculated plates were incubated at 370

o

Cfor 24 hours. Colony count was determined and bacte-ria were defined by standard procedures.7 PBS (0.1 ml)was inoculated into 10 ml of tryptic soy broth andincubated at 370

o

C for 24 hours and observed for anybacterial growth.

ResultsIn the first phase, bacterial contamination wasobserved in 7 of the 10 tested toothbrushes. Staphy-lococcus aureus, Viridans streptococci, S. epidermidisand Acinetobacter spp were isolated (count >10 5 cfu /ml) (Table 1).

In the second phase, immersion of used toothbrush-es (n=5) in chlorhexidine gluconate (0.2%) could killbacteria. Listerine was found to be less effective, as two ofthe five brushes showed microbial growth (Table 2).

In the third phase, where a plastic cap-covered toothbrush wasgiven, 7 out of 10 toothbrushes showed microbial contamination.Pseudomonas aeruginosa and Klebsiella spp were isolated from sixtoothbrushes and one toothbrush, respectively (Table 3). None ofthe packed toothbrushes (control) showed microbial growth.

DiscussionToothbrushes can get contaminated easily during their use. Reten-tion of moisture and the presence of organic matter that has come


T A B L E 3Bacterial Contamination of Toothbrushes with Cap

Serial No. of Toothbrush Bacterial Contamination Bacteria

1 Present P. aeruginosa


3 Absent Absent


5 Absent Absent

6 Present Klebsiella spp




10 Absent Absent

T A B L E 1Bacterial Contamination of Toothbrushes after Use

Serial Bacterial BacteriaNo.of ContaminationToothbrush

1 Present Acinetobacter spp, S. aureus, Viridans streptococci

2 Present Acinetobacter spp, S. aureus, Viridans streptococci

3 Present Acinetobacter spp, S. epidermidis

4 Absent Absent

5 Absent Absent

6 Present Acinetobacter spp, S. aureus



9 Absent Absent


T A B L E 2Effect of Antiseptics on Decontamination of Toothbrushes

Serial No. of Treatment with Chlorhexidine Treatment with ListerineToothbrush

1 No growth No growth

2 No growth Contaminated

3 No growth Contaminated



from the mouth may promote growth of microorganisms on thetoothbrush bristles. Such contamination may lead to colonizationof microorganisms in the mouth and possibly infection. It is alsopossible that contamination of toothbrushes can occur throughinsects.

In the present study, microbial contamination was seen in 7out of 10 toothbrushes (70%), whereas some previous studiesfound microbes on all of the tested toothbrushes.2-5 Predominantmicroorganisms isolated were Acinetobacter spp, S. aureus, S. epi-dermidis and Viridans streptococci. This is in agreement with mostsimilar studies.2-4 The bacteria were present in count >10 5 cfu / ml,which is the infective dose for many bacteria. A previous study alsocould show similar rates of bacterial contamination in toothbrush-es after use.3

In the present study, chlorhexidine was found to be effective indisinfecting contaminated toothbrushes. These results are consis-tent with previous reports.2-4 However, one of the previous studiesshowed that Listerine was more effective.1 The higher efficacy ofchlorhexidine could be the result of the extended spectrum ofaction. Also, it is relatively non-toxic, odorless and is commonlyused as a mouthwash. These properties may make chlorhexidine agood choice for disinfection of contaminated toothbrushes.

Before commencement of the study, two packed test tooth-


brushes were cultured to check for the presence of any microorgan-isms. No microbial growth was reported from either of the brushes.This shows that contamination came from the external environment.

We found no clinical studies reporting levels of microbial con-tamination of toothbrushes whose heads can be covered with plas-tic caps. In our study, we found that the use of a plastic cap leads tothe growth of microorganisms like Pseudomonas aeruginosa, agram negative aerobe and opportunistic pathogen. Therefore, it isnot advisable to cover a toothbrush head with a plastic cap. Use ofa cap may help retention of moisture that promotes growth of P.aeruginosa. ■

REFERENCES1. Caudry SD, Klitorinos A, Chan ECS. Contaminated toothbrushes and their disinfection.

J Can Dent Assoc 1995;61:511-15.2. Suma Sogi HP, Subbareddy VV, Shashi Kiran ND. Contamination of toothbrush at differ-

ent time intervals and effectiveness of various disinfecting solutions in reducing thecontamination of toothbrush. J Ind Soc Pedo Prev Dent 2002;20:81-85.

3. Bhat SS, Hedge KS, George RM. Microbial contamination of toothbrushes and theirdecontamination. J Ind Soc Pedo Prev Dent 2003;21:108-112.

4. Filho PN, Macari S, Faria G,Assed S, Ito IY. Microbial contamination of toothbrushes andtheir decontamination. Paediatric Dent 2000;22:381-4.

5. Taji SS, Rogers AH. The microbial contamination of toothbrushes. A pilot study. AustDent J 1998;43:128-30.

6. Kozai K, Iwai T, Miura K. Residual contamination of toothbrushes by microorganisms. JDent Child 1989;56:201-4.

7. Collee JG, Fraser AG, Marmion BP, Simmons AS. Mackey and McCartney. PracticalMedical Microbiology. 14th Edition. New York:Churchill Livingstone. 1996.


Abstract

A simplified technique for recording maxillomandibular

relations in complete dentures is described. This tech-

nique enables the practitioner to construct a mandibular

occlusal mini-rim directly in the mouth, to adjust it to the

required vertical dimension and to record the maxillo-

mandibular relations during a single appointment. The

mandibular record is formed with wax, used to hold the

occlusal vertical dimension anteriorly, and impression

plaster, to record the centric relation posteriorly.

THE ACCURACY OF maxillomandibular relations is of utmostimportance in the construction of complete dentures. The use ofsuch dentures is highly dependent upon a correct centric relationrecord,1 especially during the first post-insertion months.2

Several methods have been described to record maxillo-mandibular relations for the fabrication of complete dentures.These include the use of extraoral and intraoral3 tracing devices(Gothic arch), which require additional clinical time, complicatedinstrumentation and a high level of skill. They also include theswallowing procedure, using the soft wax (cones) recording asdescribed by different authors.4,5 However, some authors have ques-

tioned the validity of the swallowing procedure in determining thereference position in the sagittal plane for the maxillomandibularrelationships of complete dentures.6

Of these techniques, the direct interocclusal records using theocclusal rims (wax or plastic modeling impression compound) onrecord bases remains the most popular technique,7 even though itstill needs considerable clinical time to adjust the height of theocclusal rims to match the desired vertical height of the face.

Several materials have been used to record maxillomandibularrelations in edentulous patients, but impression plaster has gainedin popularity because of its accuracy and repeatability.8,9,10

Simplified Method This technique consists of preparing the record bases (Formatray, Kerr

USA, Romulus, MI) with the maxillary occlusal rim only prior to theappointment. The height and orientation of the maxillary rimshould be adjusted in the mouth as per the conventional methods(that is, the occlusal plane parallel to the camper plane).

The vertical dimension measurements should be performedaccording to the preferred methods—the phonetic “emma” and therespiratory methods are typically used. The occlusal verticaldimension (OVD) will be the difference between the rest verticaldimension (RVD) and the interocclusal rest space.

The next step should consist of lubricating the maxillary rimwith petroleum jelly and putting a drop of wax on the middle of the

SIMPLIFIED METHOD FOR RECORDING Maxillomandibular Relations in Complete Dentures

Paul J. Boulos, D.D.S.


posterior border of the maxillary rim to indicate the position of thetip of the tongue during closure in centric relation.

A deeply softened wax wafer, in wet heat preferably (Cavex Set Up

regular modeling wax, Cavex Holland B.V., Haarlem, the Netherlands), shouldthen be prepared and fixed in the anterior region of the mandibu-lar base using a hot spatula (Figure 1). However, in extreme angleClass II jaw relationship cases, the mandibular mini-rim would beextended to the first premolar region for better stability of theocclusal rims during the recording.

Both record bases should be inserted in the mouth and themandibular occlusal mini-rim arranged in such a way that itsdirection closely meets the maxillary rim. The patient should thenbe asked to put the tip of his or her tongue on the drop of wax sit-uated on the posterior border of the maxillary base, according tothe Schuyler technique.11

In the meantime, the practitioner’s left hand should be invert-ed, the thumb and index finger introduced between the maxillaryrim and the mandibular record base posteriorly to hold the basessteady and against the ridges. The patient should be asked to closegently while his or her chin is held between the thumb and theindex finger of the practitioner’s right hand (Figure 2). The purposeis to gently guide the closure movement. During closure, the fingersof the left hand should slide out progressively12 to clear the way forthe closing mandible, which should close until the height that isjudged correct for the vertical dimension is reached. The closingmovement of the mandible should be stopped, and the height of theface should be checked with a ruler or a caliper. The mandibularwax mini-rim should be rubbed with the thumb of the right handto adapt it against the maxillary rim. The patient should then beasked to further close his or her mandible in case it falls short of thecalculated dimension; otherwise, the softened wax is rearranged tomeet the calculated height.

Next, the mandibular base should be retrieved from the mouthand the excess wax trimmed, guided by the imprint of the maxil-lary rim on the mandibular mini-rim. The mandibular mini-rim,which should then be chilled in cold water, serves to hold themandible at the desired vertical height.

With the record bases back in the mouth in closing position,three vertical lines should be scratched, one in the midline and twolaterally, on the maxillary and the mandibular rims. This enablesthe practitioner to control and guide the centric relation recordinglater on (Figure 3). Two non-parallel V-shaped notches should becut on the maxillary rim in the molar region in preparation for theindex with the recording material.

While the maxillary rim is in the mouth, fast-setting impres-sion plaster (Xanthano, Heraeus-Kulzer, Dormagen, Germany) should bemixed to a creamy blend and spread, slightly in excess occlusally, on

Figure 1. Wax wafer in anterior region of mandibular base.

Figure 2. Closure of mandible stopped at desired vertical height.

Figure 3. Occlusal rims in mouth, with vertical control lines.

the posterior portions of the mandibular record base. The mandi-bular base should be put inside the mouth and held in place withthe fingers of the left hand, placed intraorally. The patient should beasked to close his or her jaw slowly, with the tip of the tongue on theposterior border of the maxillary base. The movement should beguided gently by the practitioner through the chin and into centricrelation. The closure would stop as the mandibular mini-rim con-tacts the maxillary rim in the already set position. The continuity ofthe vertical lines would prove the correct position (Figure 4).

The latter position should be kept unchanged until the settingof the plaster.

Before the plaster sets, the cheeks of the patient should bemassaged gently to make sure the plaster has spread evenly againstthe maxillary rim. As the final setting of the plaster (heat reaction)is completed, both bases should be retrieved from the mouth that is


fixed together. If there are doubts about the recording, separaterims should be kept and retried in the mouth to make sure that theplaster index fits the upper notches perfectly at closure.

Alternative MethodAfter setting the height of the vertical dimension and adjusting themandibular mini-rim, the patient should be asked to close slowly incentric relation, as described earlier, until the mandibular rimtouches the maxillary rim. The patient should hold his or hermandible lightly in that position.

Meanwhile, a fast-setting impression plaster should be mixed,charged into a 20 cc plastic syringe (Pronto Siringa, Artsana S.P.A., Como,

Italy) and injected into the posterior region, on the buccal aspect ofthe mandibular base. It should be built up until it reaches the max-illary rim (Figure 5). The cheeks should be gently massaged tomake sure that the plaster has spread all over the maxillary rim.The plaster has to set before retrieving the record from the mouth.

The application of this alternative method is easier, especiallyfor the practitioner who is not familiar with the manipulation ofthe plaster.

Discussion The advantages of the simplified method over the classical methodare described below.

RapidityThe rapidity of the technique reduces considerably the time neededfor the recording. In the conventional technique, the mandibularocclusal rim is constructed outside the mouth to an arbitrary heightand adjusted to contact evenly the maxillary rim to meet the heightof the occlusal vertical dimension already calculated. This proce-dure will be achieved with many limited readjustments of theocclusal surface of the mandibular rim to attain the hiatus-free con-tact between the rims. Certainly, the occlusal rims need to be testedin the mouth after every readjustment to assess the progress of theprocedure. In addition, the risk of deviation of the mandible due toarising posterior prematurities is always possible with the conven-tional technique, especially for the inexperienced practitioner.

By contrast, when using the simplified technique, the mandi-bular anterior mini-rim is constructed directly in the mouth devoidof the posterior portions of the occlusal rim and adjusted easily tothe required height with a single maneuver. The posterior regionswill be filled later by the impression plaster record.

ReliabilityThe results of the new method are reliable because the risks ofdeviation of the mandible and displacement of the soft tissuesunder the record bases13 are significantly reduced. This is mostlybecause the properties of the impression plaster, which is fluid dur-ing the first stage of mixing, do not present any resistance for clo-sure during the recording of the centric relation. The pressure will

Figure 4. Interocclusal recording in mouth with impression plaster record.

Figure 5. Alternative method: injection of impression plaster between maxillaryrim and mandibular record base.


be minimal and evenly distributed on both sides of the arch.Once it is set, the hard and unyielding nature of the plaster will

keep the stability of the centric record in contrast to other record-ing materials (wax, zinc oxide bite registration paste or plasticmodeling impression compound).

SimplicityThe application of the new method is relatively simple and does notrequire special skills.

Finally, according to this technique, the maxillomandibularrelations are recorded with two different materials best fit for eachcomponent of these relations: wax for the occlusal vertical dimen-sion and impression plaster for the centric relation.

ConclusionA simplified method for recording the maxillomandibular relationsin complete dentures is presented. This method, which is based onthe conventional techniques of investigation of the vertical dimen-sion and the centric relation, offers the advantages of time, reliabil-ity and simplicity over previously described techniques. ■

REFERENCES1. Fenlon MR, Sherrif M,Walter JD.Association between the accuracy of the intermaxillary

relations and complete denture usage. J Prosthet Dent 1999 May;81:520-525.2. Dervis E. The influence of the accuracy of the intermaxillary relations on the use of com-

plete dentures: a clinical evaluation. J of Oral Rehabil 2004;31:35-41.3. Langer A, Michman J. Intraoral technique for recording vertical horizontal maxillo-

mandibular relations in complete dentures. J Prosthet Dent 1969;21:599-606.4. Hakim-Abdel AM. The swallowing position as a centric relation record. J Prosthet Dent

1982; 47:12-15.5. Ismail YH, George WA. The consistency of the swallowing technique in determining

occlusal vertical relation in edentulous patients. J Prosthet Dent 1968;19:230-236.6. Millet C, Jeannin C,Vincent B, Malquarti G. Report on the determination of occlusal ver-

tical dimension and centric relation using swallowing in edentulous patients. J OralRehabil 2003;30: 1118-1122.

7. Jaggers JH, Javid NS, Colaizzi FA. Complete denture curriculum survey of dental schoolsin the United States. J Prosthet Dent 1985;53:736-739.

8. Urstein M, Fitzig S, Moskona D, Cardash HS. A clinical evaluation of materials used inregistering interjaw relationships. J. Prosthet Dent 1991; 65:372-377.

9. Frazier QZ, Wesley RC, Lutes MR, et al. The relative repeatability of plaster interocclusaleccentric records for articulator adjustment in construction of complete dentures. JProsthet Dent 1971;26: 456-67.

10. Müller J, Götz G, Hörz W, Kraft E. Study of the accuracy of different recording materials.J Prosthet Dent 1990;63:41-46.

11. Schuyler Ch. Intraoral method of establishing maxillomandibular relation. JADA 1932;19:1012-1021.

12. Hickey JC, Zarb GA, Bolender CL. Boucher’s Prosthodontic Treatment for EdentulousPatients. 9th Ed. St Louis:Mosby. 1985:288-290.

13. Hemphill CD, Parker ML, Regli CP. Effects of uneven occlusal contact when registeringmaxillomandibular relations. J Prosthet Dent 1972;28:357-359.


Abstract

This study was done to analyze the effect of different sur-

faces and different surface applications on the bonding

strength of porcelain repair material and to compare these

factors with one another. Three different substructures of

10 mm diameter and 4 mm thickness were used for the

repair surface: metal, metal on porcelain and porcelain.

The surfaces of half of the samples were roughened with

an air abrasion tool; the surfaces of the other half were

treated with a diamond bur. The specimens were ultrason-

ically cleaned in distilled water. A silane coupling agent

and a bonding agent were applied to the surfaces of all

the samples. Resin composite was applied to each spec-

imen. All specimens were stored in distilled water for 24

hours before being thermocycled. After thermocycling,

specimens were stored in distilled water for an additional

seven days before being subjected to a shear load.

The highest bonding strength was observed in the

samples with a metal substructure, the surfaces of which

were prepared with an air abrasion tool; the lowest bond-

ing strength was observed in the samples with a metal

substructure, the surfaces of which were prepared with a

diamond bur. When different substructures were examined

in terms of bonding strength, the highest bonding strength

was statistically observed in metal-on-porcelain substruc-

tures, and the lowest bonding strength was observed in

the porcelain substructure. When they were examined in

terms of surface processes, the highest bonding strength

was statistically observed in the samples whose surfaces

were prepared with an air abrasion tool, and the lowest

bonding strength was observed in the samples whose sur-

faces were prepared with a diamond bur.

PORCELAIN-FUSED-TO-METAL CROWNS are widely acceptedand used in clinical practice. However, they occasionally demon-strate fracture of the brittle ceramic veneer. Failure resulting fromporcelain fracture has been reported to range from 2.3% to 8%.1-3

The cause of clinical fracture of veneering porcelain on ceramometalcrowns is multifactorial. Lack of proper framework support for the

Effect of Different Surfaces and Surface Applications on Bonding Strength of Porcelain Repair Material

Zeynep Duymus Yesil, D.D.S., Ph.D.; Serpil Karaoglanoglu, D.D.S., Ph.D.;Nilgün Akgül, D.D.S., Ph.D.; Nur Ozdabak, Dr. Med. Dent.; Nurcan Ozakar Ilday, Med. Dent.

porcelain, intraceramic defects or parafunctional occlusion cancause this inconvenient problem.4

Ideally, remake of the restoration is desirable, but is not alwaysfeasible. The ability to perform an intraoral repair can be of greatbenefit to the patient.5 However, for the repair to withstand func-tional loads, the bond between the repair material and remainingrestoration must be strong and durable.6

Three conditions are suggested for repair of porcelain frac-tures: 1. fracture in porcelain only with no metal exposure; 2. frac-ture with both porcelain and metal exposed; and 3. fracture withsubstantial metal exposure.7 Various methods have been intro-duced to repair fractured porcelain with composite.8-11 Mechanicalroughing of porcelain surfaces with a coarse diamond bur hasimproved repair strengths.12,13 Sandblasting with aluminum oxideis another method of surface roughing.7 And porcelain can also beetched with hydrofluoric (HF) acid or acidulated phosphate fluo-ride gel to facilitate micromechanical retention of the composite.14-16

Until recently, composite repair of fractured porcelain achievedlittle clinical success. Intraoral repair of fractured porcelain tradi-tionally relied on mechanical roughening of the fractured surface,followed by application of a silane coupling agent to enhance theresin to porcelain bond.17

If a small part of the porcelain is missing, it might be a rea-sonable solution to repair it intraorally with a light-curing compos-ite resin. A large fracture of porcelain can also be repaired by thesame technique, but the result will never be as durable or estheticas the original restoration.18

This study was done to analyze the effect of different surfacesand different surface applications on the bonding strength ofporcelain repair material and to compare these factors with oneanother.

Materials and MethodsA total of 42 cylindrical specimens were fabricated: 14 from porcelain(Ceramco, Burlington NJ, Weybridge UKKT 15 2S, USA); 14 from a Ni-Cr alloy(Wiron 99, Bego, Bremen, Germany); and 14 from a Ni-Cr alloy and porcelain.

Fabrication of the specimens was as follows:● Porcelain specimens. Porcelain was condensed in a split

brass mold (1.0 cm diameter and 0.4 cm thickness) withModisol separating agent (Vident). Condensed cylinders wereplaced on a platinum foil sagger tray and fired at 940

o

C undervacuum in a calibrated porcelain furnace (Ugin/Dentaire [Elips],

France).● Porcelain and metal specimens. Inlay wax cylinders (1.0 cm

diameter; half of the cylinders 0.4 cm thickness, and the otherhalf 0.2 cm thickness) were invested and cast with the use ofNi-Cr alloy. The metal cylinders were air abraded with 50 µmaluminum oxide. The opaque was applied to the side with thethinner section surfaces and the porcelain was condensed. Themetal and porcelain surface was finished flat with a laboratorymedium-grit sintered diamond bur.

● Metal specimens. Inlay wax was flowed into a silicone mold(1.0 cm diameter and 0.4 cm thick). The wax cylinder wasinvested and cast with the use of a Ni-Cr alloy. The cylinderswere cleaned in an ultrasonic unit in distilled water (Figure 1).Each of the substrates was embedded in a phenolic ring

(Buehler Ltd, Lake Bluff, IL) with polymethyl methacrylate resin (De Trey

RR, Dentsply, England). Metal, metal on porcelain and porcelain samplegroups were divided into two equal-numbers groups of 14 sampleseach. The surfaces of half of the samples (seven metals, seven metalon porcelains and seven porcelains) were air abraded with 50 µmaluminum oxide particles for 15 seconds with an intraoral sand-blasting device (Prepstar, Danville Engineering, Danville, USA), rinsed anddried. The surfaces of the other half of the samples were roughenedwith a coarse diamond bur (No. 520.4, Abrasive Technologies, Columbus,

Ohio), and each material to be tested was bonded to the preparedporcelain by following the manufacturer’s directions. The speci-mens were ultrasonically cleaned in distilled water for 10 minutes.

A silane coupling agent and a bonding agent were applied tothe mid parts of all the samples in accordance with the recommen-dations of the manufacturers. The adhesives were used in accor-dance with the manufacturer.A silane coupling agent (Clearfil Se Bond

Primer; Kuraray, Ltd., J Morita USA, Inc., Tustin, Calif.) and bonding agent(Clearfil Se Bond; Kuraray, Ltd., J Morita USA, Inc., Tustin, Calif.) were appliedto the complete samples (metal, metal on porcelain and porcelain)and allowed to air dry. The adhesives were used in accordance withthe manufacturer. Resin composite (Valux Plus 3M ESPE, Seefeld,

Germany) was applied to each specimen according to the manufac-turer’s instruction using a Teflon split matrix, 3.5 mm diameter and2 mm thick (Ultradent, South Jordan, Utah). Resin composite was poly-merized with 40-second visible light applications (Elipar II, 3M ESPE,

Seefeld, Germany).After the matrix was removed, an additional 40 sec-onds of visible light was applied.

All specimens were stored in 37o

C distilled water for 24 hoursbefore being thermocycled between 5

o

C and 55o

C for 300 cycleswith a 30-second dwell time. After thermocycling, specimens werestored in 37

o

C distilled water for an additional seven days beforebeing subjected to a shear load.

The Hounsfield testing machine (Hounsfield Test Equipment

Company, HTE 37 Fullerton Road, Croydon, England), with a 0.5 cm/mincrosshead speed and chisel apparatus, was used to direct a parallelshearing force as close as possible to the resin/substrate interface.


Figure 1. Metal, porcelain and metal-porcelain specimens.


The shear load in newtons at the point of failure was noted andforce was calculated in megapascals (MPa).

An analysis of variance (ANOVA) was applied to the data.Mean and standard deviations were calculated.

ResultsThe results of the variance analysis used to evaluate the data areshown in Table 1.

It was statistically determined that the type of substructureused for repair, the surface application and interactions are notimportant (p> 0.05).

The mean and standard deviation results of the dataobtained are shown in Table 2. The highest bonding strength wasobserved in the samples with metal substructure, the surfaces ofwhich were prepared with air abrasion (11.99 MPa); then camethe samples with metal-on-porcelain substructure, the surfaces ofwhich were roughened with air abrasion (11.30 MPa). The lowestbonding strength was observed in the samples with metal sub-structure, the surfaces of which were prepared with a diamondbur (9.35 MPa).

When different substructures were examined in terms ofbonding strength, the highest bonding strength was statisticallyobserved in the metal-on-porcelain substructures (11.27 MPa) andthe lowest bonding strength was observed in the porcelain sub-structure (10.03 MPa) (Table 3). When they were examined interms of surface processes, the highest bonding strength was sta-tistically observed in the samples whose surfaces were preparedwith air abrasion, and the lowest bonding strength was observed inthe samples whose surfaces were prepared with a diamond bur.

DiscussionThis study examined the shear bond strengths of composite mate-rial used for repair in three representative situations: fracture with-in porcelain; fracture within porcelain with exposure of someceramic alloy; and fracture with complete porcelain delaminationand exposure of a large section of alloy. When the fracture occurswith metal exposure, the repair is more problematic.

Traditionally, attempts to bond resin to metal have involvedroughening the metal to provide mechanical retention of the resin.One easy method of enhancing bond strength is roughening thesurface by air abrasion with aluminum oxide, thereby increasingthe surface area for bonding and decreasing surface tension.19

High composite alloy bonds have been reported with basemetal alloys treated with sandblasting.20,21 A previous study report-ed that the alumina content of base alloys increased up to 37% aftersandblasting, and ultrasonic cleaning resulted in only minorremoval of the embedded alumina.22 Sandblasting the base alloysurface that resulted in the surface containing a significant amountof alumina particles, which affects bond strength, has been report-ed.23 Porcelain surface sandblasted with alumina resulted in micro-mechanical roughening and covering with small alumina parti-

T A B L E 1 Results of Analysis of Variance

Source Type III df Mean Square FSum of Squares

Surface Treatments (ST) 10.073 1 10.073 1.698

Substrate 13.770 2 6.885 1.160

ST X Substrate 21.251 2 10.626 1.791

Error 284.803 48 5.933

T A B L E 2 Mean and Standard Deviation Results of Results Obtained

Tecniques Substrate N Mean(MPa) SD

Air Abraz M 7 11.99 2.09

M-P 7 11.30 2.76

P 7 9.99 2.55

Diamond Bur M 7 9.35 2.89

M-P 7 11.25 1.83

P 7 10.04 2.32

T A B L E 3 Mean(MPa) SD

Metal 10.67 2.80

Metal-porcelain 11.27 2.28

Porcelain 10.04 2.49


cles.24 The reported bond strengths of the sandblasted porcelainsurface ranged from 9 to 17 MPa.25

The present study yielded results within the limits mentionedby the above researchers.

Chung and Hwang6 reported a significant increase in bondstrength of composite-to-base alloy when the surface was airabraded with aluminum oxide. Suliman et al25 noted no significantdifferences between diamond roughening, air abrasion andhydrofloric acid treatment. Unglazed porcelain surfaces have beenshown to contribute to stronger composite-porcelain bonding,10

and the application of silane, regardless of prior surface treatment,has consistently raised bond strengths in laboratory studies.14,26

Kupiec et al27 found that hydrofluoric acid treatment enhancedbond strength, especially when used with a silane agent. Similarly,Stangel et al14 demonstrated that etching porcelain with hydrofloricacid significantly contributed to increased bond strength of thecomposite.

Roughening with air abrasion and diamond bur was used asthe surface application in the present study. As hydrofluoric acidwas present in the bond used; it was applied to all the samples.

Mechanical alteration of a porcelain surface is more importantthan agents that promote chemical bonding of composite resin toporcelain.28 With the above researchers’ views in mind, silane, a cou-

pling agent, and a bonding agent were applied to the surfaces towhich the composite would be applied following the mechanicalroughening.

According to Anusavice,29 an infinite number of fracture pathsof the veneer porcelain can occur. Clinically, porcelain fracture can beseen with no exposure of the metal substrate or with complete deve-neering of porcelain with extensive metal exposure. Repairs made onmultiple substrates may behave differently than those made only ona ceramic surface. Previous studies have primarily examined repairsmade solely to a porcelain or alloy substrate.4,10,30-32 Few have testedbond strengths to a combined surface.6 Bond strength valuesdepended on the system used, with the strongest bonds to porcelainresulting in cohesive failure in the porcelain substrate.11,33

Chung and Hwang,6 in their study, in which they applied dif-ferent composite resins and their bonds to different substrates,determined that the highest degree of bonding strength was in thesamples with the metal substrates.

It was found that the best bond between the fractured surfaceand the repair composite resin was obtained with a porcelaininstead of metal surface.8,18 Because the success of the adherencedepends on the amount of remaining porcelain surface, it was pro-posed to extend the bonding surface of the fractured porcelain toimprove the bond strength of the repair material.34


There is little information on the bond strength of porcelain repairmaterials to the metal porcelain combined surface.6 When therepaired surfaces were compared in terms of the bonding strength,the highest bonding strength was determined in the subjects withmetal-on-porcelain substructure. This result is in harmony withthe findings of the above-mentioned researchers.

Research on porcelain repair has included shear, tensile andthree-point loading. The porcelain-resin interface has also beensubjected to fatigue loads.30 The concept of fatigue testing is applic-able to brittle ceramic materials;29 but when such testing is appliedto the porcelain-resin interface, large standard deviations suggestan abnormally distributed population because some specimens donot fail.30 A shear test was chosen for this study because multiplesubstrates were used. In addition, anterior restorations are subject-ed primarily to shear stresses, and the shear test is consideredappropriate for quantifying the strength of porcelain repairs.35

The use of thermocycling is variable in the literature. Moststudies using thermocycling have reported that bond strengths arereduced by thermocycling.11,36 A common finding among many ofthese studies was a reduction in shear bond strength after pro-longed water storage and/or thermocycling.2,10,11,30-32 The effects ofmoisture, thermal stress and fatigue on bond strength have beenexplored.3,11,30

Since the effect of thermocycling was not examined in ourstudy, we could not form a control group. So thermocycling wasapplied in the way recommended in the literature.3,10,11,30,31,32,36

ConclusionIt was statistically determined that the type of substructure, thesurface application and the interactions were not important. Thehighest bonding strength was observed in the samples with metalsubstructure, the surfaces of which were prepared with air abrasion.The lowest bonding strength was observed in the samples withmetal substructure, the surfaces of which were prepared with a dia-mond bur.

When different substructures were examined in terms of bond-ing strength, the highest bonding strength was statistically observedin metal-on-porcelain substructures, and the lowest bondingstrength was observed in the porcelain substructure. When theywere examined in terms of surface processes, the highest bondingstrength was statistically observed in the samples whose surfaceswere prepared with air abrasion, and the lowest bonding strengthwas observed in the samples whose surfaces were prepared with adiamond bur. ■

REFERENCES1. Libby G, Arcuri MR, LaVelle WE, Hebl L. Longevity of fixed partial dentures. J Prosthet

Dent 1997;78:127-131.2. Strub JR, Stiffler S, Schärer P. Causes of failure following oral rehabilitation: biological

versus technical factors. Quintessence Int 1988;19:215-222.3. Coornaert J,Adriaens P, De Boever J. Long-term clinical study of porcelain-fused-to-gold

restorations. J Prosthet Dent 1984;51:338-342.

4. Bello JA, Myers ML, Graser GN, Jarvis RH. Bond strength and microleakage of porcelainrepair materials. J Prosthet Dent 1985;54:788-791.

5. Haselton DR, Diaz-Arnold AM, Dunne JT. Shear bond strengths of 2 intraoral porcelainrepair systems to porcelain or metal substrates. J Prosthet Dent 2001;86:526-531.

6. Chung KH, Hwang YC. Bonding strengths of porcelain repair systems with various sur-face treatments. J Prosthet Dent 1997;78:267-274.

7. Bertolotti RL, Lacy AM, Watanabe LG. Adhesive monomers for porcelain repair. Int JProsthodont 1989;2:483-489.

8. Beck DA, Janus DE, Douglas HB. Shear bond strength of composite resin porcelain repairmaterials bonded to metal and porcelain. J Prosthet Dent 1990;64:529-533.

9. Bailey JH. Porcelain-to-composite bond strengths using four organosilane materials. JProsthet Dent 1989;61:174-177.

10. Diaz-Arnold AM, Schneider RL,Aquilino SA. Bond strength of intraoral porcelain repairmaterials. J Prosthet Dent 1989;61:305-309.

11. Pratt RC, Burgess JO, Schwarts RS, Smith JH. Evaluation of bond strength of six porce-lain repair systems. J Prosthet Dent 1989;62:11-13.

12. Jochen DG, Caputo AA. Composite resin repair of porcelain denture teeth. J ProsthetDent 1977;38:673-679.

13. Ferrando JM, Graser GN, Tallents RH, Jarvis RH. Tensile strength and microleakage ofporcelain repair materials. J Prosthet Dent 1983;50: 44-50.

14. Stangel I, Nathanson D, Hsu CS. Shear strength of the composite bond to etched porce-lain. J Dent Res 1987;66:1460-1465.

15. Tylka DF, Stewart GP. Comparison of acidulated phosphate fluoride gel and hydrofluoricacid etchants for porcelain-composite repair. J Prosthet 1994;72:121-127.

16. Della Bona A, van Noort R. Shear vs. tensile bond strength of resin composite bonded toceramic. J Dent Res 1995;74:1591-1596.

17. Council on dental materials, instruments and equipment, porcelain repair materials. JAm Dent Assoc 1991;122:124-130.

18. Hirschfeld Z, Rehany A. Esthetic repair of porcelain in a complete-mouth reconstruc-tion: a case report. Quintessence Int 1991;22:945-947.

19. Swift EJ Jr. New adhesive resins. A status report for the American Journal of Dentistry.Am J Dent 1989;2:258-260.

20. Aquilono SA, Diaz-Arnold AM, Priotrowski TJ. Tensile fatigue limits of prosthodonticsadhesives. J Dent Res 1991;70:208-210.

21. Chang JC, Powers JM, Hart D. Bond strength of composite to alloy treated with bondingsystems. J Prosthodont 1993;2:110-114.

22. Kern M, Thompson VP. Sandblasting and silica coating of dental alloys: volume loss,morphology, and changes in the surface composition. Dent Mater 1993;9:155-161.

23. Diaz-Arnold A, Keller JC, Wightman JP, Williams VD. Bond strength and surface charac-terization of a Ni- Cr- Be alloy. Dent Mater 1996;12:58-63.

24. Kern M, Thompson VP. Sandblasting and silica coating of a glass-infiltrated aluminaceramic: volume loss, morphology, and changes in the surface composition. J ProsthetDent 1994;71:453-461.

25. Suliman AH, Swift EJ Jr, Perdigao J. Effects of surface treatment and bonding agents onbond strength of composite resin to porcelain. J Prosthet Dent 1993;70:118-120.

26. Hayakawa T, Horie K,Aida M, Kanaya H, Kobayashi T, Murato Y. The influence of surfaceconditions and silane agents on the bond of resin to dental porcelain. Dent Mater1992;8:238-240.

27. Kupiec KA,Wuertz KM, Burkmeier WW,Wilwerding TM. Evaluation of porcelain surfacetreatments and agents for composite- to- porcelain repair. J Prosthet Dent 1996;76: 119-124.

28. Thurmond JW, Burkmeier WW, Wilwerding TM. Effect of porcelain surface treatmentson bond strength of composite bonded to porcelain. J Prosthet Dent 1994;72:355-359.

29. Anusavice KJ. Phillips’ science of dental materials. 10th Ed. Philadelphia:WB SaundersCo, 1996:63,309,606.

30. Llobell A, Nicholls JI, Kois JC, Daly CH. Fatigue life of porcelain repair systems. Int JProsthodont 1992;5:205-213.

31. Appeldoorn RE, Wilwerding TM, Burkmeier WW. Bond strength of composite resin toporcelain with newer generation of porcelain repair systems. J Prosthet Dent 1993;70:6-11.

32. Cooley RL, Tseng EY, Evans JG. Evaluation of a 4-META porcelain repair systems. J EsthetDent 1991;3:11-13.

33. Wolf DM, Powers JM, O’Keefe KL. Bond strength of composite to porcelain treated withnew porcelain repair agents. Dent Mater 1992;8:158-161.

34. Berksun S, Kedici PS, Saglam S. Repair of fractured porcelain restorations with compos-ite bonded porcelain laminate contours. J Prosthet Dent 1993;69:457-458.

35. Leibrock A, Degenhart M, Behr M, Rosentritt M, Handel G. In vitro study of the effect ofthermo- and load-cycling on the bond strength of porcelain repair systems. J OralRehabil 1999;26:130-137.

36. Newburg R, Pameijer CH. Composite resins bonded to porcelain with silane solution. JAm Dent Assoc 1978;96:288-291.

Abstract

Alport syndrome (AS) represents a genetic cause of renal

failure that affects about 1 in 5,000 Americans. In cases of

AS, the problem resides on the X chromosome. Specific

mutations to the gene cause defects in one of several sub-

units of Type IV collagen. Accumulation of collagen types

V and VI, with subsequent abnormalities in the permeabil-

ity and sclerosis of the kidney, leads to renal failure.

Renal failure causes severe bone disease since the

kidney processes vitamin D, which is necessary for calci-

um absorption from the intestine. Therefore, in a patient

with chronic renal disease, vitamin D is not produced,

resulting in a decrease in intestinal absorption of calcium

and subsequent lower serum calcium levels. Furthermore,

the decreased phosphate excretion by the kidney leads to

elevation of plasma phosphate, which increases the

amounts of parathyroid hormone required to move calcium

from bone (secondary hyperparathyroidism) to maintain

plasma calcium at a constant level and preserve an

appropriate calcium-phosphorous ratio.

We have described AS, reviewed the pathogenesis

and presented an interesting extreme case with numerous

craniofacial manifestations.


ALSO KNOWN AS hereditary deafness nephropathy, Alport syn-drome (AS) presents as a genetic cause of kidney failure and afflictsabout 1 in 5,000 Americans. It also affects the cochlea and the eye.

AS is identified by its presence on the X chromosome, specifi-cally, the gene COL 4A5. Mutations to the gene cause defects in oneof several subunits of Type IV collagen, specifically, � 3- � 4- and� 5- chains, which may be absent. As a compensatory response,there is an accumulation of collagen types V and VI in the base-ment membrane of the glomerulus. Subsequent abnormalities inthe permeability and sclerosis of the kidney tissue will lead to renalfailure.1

A group of hereditary diseases characterized by thrombocy-topenia, renal disease, cataracts and deafness are called Alport-likesyndromes because they are clinically similar. But the geneticmutations linked to this group of disorders are different from thoseseen in AS.2,3 There are two genetic types: autosomal dominant (1%of the cases), and autosomal recessive (14% of the cases). The X-linked AS constitutes 85% of the cases of Alport and Alport-likesyndromes. The condition is more severe in males than females, butthere is no racial predilection.4

Renal DysfunctionApproximately one million nephrons are present in each normalkidney, but since chronic renal failure (CRF) is characterized by aloss of nephrons, AS patients exhibit progressive destruction ofthem. To compensate for the destroyed renal tissue, hypertrophy ofthe remaining healthy kidney proceeds to maintain the glomerularfiltration rate and continues until the renal reserve has beenexhausted. But the kidney hypertrophy leads to increased glomeru-lar capillary pressure, which damages the capillaries and representsyet another cause of renal dysfunction.

Alport SyndromeReport of a Case with Severe Maxillofacial Manifestations

Kurt Friedman, D.D.S., M.S.; Ines Velez, D.D.S., M.S.

The involvement of the glomerulus in patients with AS produceshematuria as an earliest manifestation. Proteinuria and hyperten-sion develop in adulthood, with severity increasing with age.Initially, the clinical findings are unremarkable, but with time, pro-gressive renal failure, manifested by edema, chronic anemia, severebone alterations and hypertension, is observed.5

Hearing defects, including bilateral high frequency hearingloss, become apparent by late childhood, before the onset of renalfailure. Some patients with AS also exhibit ocular manifestations,such as lenticonus and retinopathy, which manifest at the time ofkidney failure. Proliferation of the smooth muscle of the esophagusand the tracheobronchial system is seen in some cases,6 as is men-tal retardation.7

Establishing a DiagnosisThe diagnosis of AS is based upon family history, physical exami-nation, immunohistochemical analysis of basement membraneType IV collagen—using skin or kidney tissue—and electron micro-scopic renal biopsy analysis. Genetic testing is available for X-linked cases.

Since there is no specific treatment that can cure AS, a kidneytransplant is usually needed. Unfortunately, the immune systemmay react against the normal collagen of the new kidney, destroy-ing the transplant and leading to end stage renal failure.8

Renal failure causes severe bone disease since the kidneyprocesses vitamin D, which is necessary for calcium absorptionfrom the intestine. Therefore, in a patient with chronic renal disease,vitamin D is not produced, resulting in a decrease in intestinalabsorption of calcium and subsequent lower serum calcium levels.Furthermore, the decreased phosphate excretion by the kidney leadsto an elevation of plasma phosphate, which increases the amounts of


Figure 1. Clinical view. Facial deformity is evident.

Figure 2. Alveolar ridge and gingival enlargement. Diastemas.

Figure 3. CT scan; axial view. Craniofacial lesions.

Since there is no specific treatment that can

cure AS, a kidney transplant is usually needed.

Unfortunately, the immune system may react

against the normal collagen of the new

kidney, destroying the transplant and leading

to end stage renal failure.8

parathyroid hormone required to move calcium from bone (sec-ondary hyperparathyroidism) to maintain plasma calcium at a con-stant level and preserve an appropriate calcium-phosphorous ratio.The turnover of the bone increases, as does the number of boneremodeling centers; and if calcification of osteoid is inhibited, bonedisease becomes severe with the possibility of pathologic fracture.The result is osteomalacia with generalized loss of the lamina durabeing seen as an early manifestation of the condition. A decrease intrabecular density is observed, and brown tumors (sometimes mul-tiple) of hyperparathyroidism usually develop. Osteomalacic bonemay show mineralization and osteosclerosis later.

Anemia is always present, mainly as a result of the decreased pro-duction of red blood cells by the bone marrow.This is due to the inabil-ity of the kidneys to secrete erythropoietin, the hormone needed tostimulate normal bone marrow to produce red cells. Blood loss, result-ing from the malfunction of platelets in patients suffering from ure-mia,and hemolysis,seen in advanced renal failure,are also factors thatcontribute to the severe anemia observed in those cases. Furthermore,the normal life span of erythrocytes is about four months. But in renalfailure patients, the life of the red blood cells is reduced due to thechemical effect of the uremia. In addition, the accumulation of uremictoxins may play a role in depressing bone marrow function.

A person with severe anemia tries to compensate for this con-dition by increasing bone marrow tissue, and, subsequently, bloodcell production. It can be done easily by somebody with normalbone marrow, but in renal failure, the bone marrow’s capacity tocompensate is decreased, even though bone marrow tissue may begenerated in sites such as the mandible and skull.

The effects of CRF on bone are primarily due to secondaryhyperparathyroidism. The condition that develops in these patients


is called osteitis fibrosa cystica, and it results from the degenerationof the multiple brown tumors. One clinical manifestation of thisentity is the striking enlargement of the jaws.9 Bone deformity andwidening of bone plates also occur as a result of the body’s effortsto compensate for anemia. This combination of anemia, secondaryhyperparathyroidism, osteomalacia, osteitis fibrosa cystica andosteosclerosis leads to the alteration of bone in end stage renal dis-ease patients.

Case ReportA 29-year-old black female was referred to the oral and maxillo-facial surgeon because of severe bleeding of the gingiva. Medicalhistory showed a previously confirmed diagnosis of Alport syn-drome. The patient developed progressive loss of renal function,and a kidney transplant was necessary. Failure of two renal trans-plants and end stage renal disease led to dialysis as the onlytreatment option.

Examination revealed a terminally ill black female patientexhibiting severe cosmetic and functional deformity. Significantobservations included painless, bilateral and symmetrical severeswelling of the maxilla with involvement of the orbital floor,extreme bilateral enlargement of the mandible and multiplediastemas. The bone expansion caused swelling and distortion ofthe face and subsequent widening of the alveolar ridge, as well astooth displacement and tooth mobility, impaired mastication andspeech difficulties. Fibrosis and bleeding of the gingiva and verypoor oral hygiene were factors also recorded.

The radiographs and CT scan exhibited generalized expansive,mixed, radiolucent and radioopaque areas over the entire craniofa-cial skeleton. Most of the radiographic lesions were completely dif-

Figure 4. CT scan; sagital view. Craniofacial lesions. Figure 5. CT scan; tri-dimensional view. Surface rendering. Generalized lesions.Loss of cortical bone (secondary hyperparathyroidism) is evident.


fuse and some areas exhibited ground glass appearance. The skullbones showed radiopaque areas and radiolucent lesions withwidening of bone plates. The radiolucent lesions may have repre-sented bone marrow defects or brown tumors.

The severe bone deformity present in this case may havebeen caused by a combination of compensatory anemia lesions,secondary hyperparathyroidism, osteomalacia, osteitis fibrosacystica and posterior hypercalcification. The gingival bleedingnoticed in this patient was due to malfunction of the platelets anddecrease in bone marrow cell production, usually present inpatients with an accumulation of uremic toxins and exacerbatedby poor oral hygiene.

ConclusionWe have described Alport syndrome, reviewed the pathogenesisand presented an extreme case with numerous craniofacial mani-festations. Besides extreme bone deformities, patients may showfractures, epistaxis, gingival bleeding, anemia, lenticonus andretinopathy. Other associated maxillofacial problems include hear-ing and speech difficulties and malocclusion.

AS is a condition initiated by a genetic alteration of Type IVcollagen, followed by subsequent abnormalities in the permeabilityof the kidney, resulting in renal failure. In advanced cases, a combi-nation of secondary hyperparathyroidism, osteomalacia, osteitisfibrosa cystica and osteosclerosis leads to dramatic bone changes.

Renal failure also causes anemia, the result of different mecha-nisms, such as lack of erythropoietin, decreased life span of ery-throcytes, blood loss produced by platelet malfunction and toxicdepression of bone marrow function. A compensatory increase inbone marrow production may also lead to maxillary, mandibularand skull lytic lesions and enlargement.

The pathogenesis of the mechanisms previously describedmay be enough to explain the severe bone changes observed in thispatient. ■

REFERENCES1. Gross O, Netzer KO, Lambrecht R, Seibold S, Weber M. Meta-analysis of genotype-phe-

notype correlation in X-linked Alport syndrome: impact on clinical counseling. NephrolDial Transplant 2002;17:1218-1227.

2. Epstein CJ, Sahud MA, Piel CF, Goodman JR, Bernfield MR, Kushner JH, Ablin AR.Hereditary macrothrombocytopenia, nephritis and deafness. Am J Med 1972;52:299-310.

3. Rocca B, Laghi F, Zini G, Maggiano N, Landolfi R. Brit J Haemat 1993;85:423-426.4. Longo I, Porcedda P, Mari F et al. COL 4A3/COL 4A4 mutations from familial hematuria

to autosomal dominant or recessive Alport syndrome. Kidney Int 2002;61(6): 1947-1956.5. Mothes H, Heidet L, Arrondel C, Richter KK, et al. Alport syndrome associated with dif-

fuse leiomyomatosis: COL4A5-COL 4A6 deletion associated with a mild form of Alportnephropathy. Nephrol Dial Transplant 2002;17:70-74.

6. Dische FE, Weston MJ, Parsons V. Abnormally thin glomerular basement membranesassociated with hematuria, proteinuria or renal failure in adults. Am J Nephrol 1985;5:103-109.

7. Meloni I, Vitelli F, Pucci L et al. Alport syndrome and mental retardation: clinical andgenetic dissection of the contiguous gene deletion syndrome in Xq 22.3 J Med Genet2002;39(5):359-365.

8. Byrne MC, Budisavljevic MN, Fan Z, et al. Renal transplant in patients with Alport’s syn-drome. Am J Kidney Dis 2002;39(4):769-775.

9. Gavalda C, Bagan JV, Scully C, et al. Renal Hemodialysis Patients. Oral, salivary, dentaland periodontal findings in 105 adult cases. Oral Dis 1999;5:292-302.


Abstract

Surgical soft tissue exposure of im-

pacted teeth can now be performed

with little to no discomfort and excel-

lent postoperative healing. This paper

focuses on the techniques used in

performing this procedure.

THE IMPLEMENTATION of lasers in den-tistry has given dentists a completely newinstrument in their armamentarium. Inrecent years, lasers have proven to be an inte-gral part of many dental practices.1-3 Use ofthe laser allows the general clinician to per-form a variety of procedures without theadjunctive use of local anesthesia, alleviatingpatient anxiety, while increasing the clini-cian’s own capabilities to perform proceduresthey might otherwise have referred to a spe-cialist.4 Laser use has also facilitated specialtypractice by allowing the specialist to performmany soft tissue surgical procedures moreexpeditiously and with excellent postopera-tive healing. It also has eliminated the needfor local anesthesia in many cases.1,5,6

The Er,Cr:YSGG dental laser can accom-plish these tasks by using a wavelength of

2,780 nm to energize water particles deliv-ered at the fiber optic tip through variousratios of water and air to cut both hard andsoft tissue effectively without causingmicrocrazing in the enamel matrix.7,8 Withrespect to soft tissue, it can use the existinghydration of the oral soft tissue to performits task.7,9 This interaction at the tissue sur-face with energized water particles istermed “hydrokinetic” energy.6 With use ofthe Er, Cr: YSGG laser, the clinician is able toachieve exceptional results in both theoperating procedure and in postoperativehealing.

Clinical TechniqueCase OneAn 8-year-old child presented to the dentalclinic with both maxillary central incisorsimpacted in the soft tissue. Because of theage of the child and the possible sequelae ofthe laterals drifting mesially and futureorthodontic complications, the decision wasmade to surgically expose the teeth.7 Thelaser technique was employed using a T4 tipand three consecutive settings to firstobtain laser anesthesia. One of the manybenefits of using the laser is being able toforgo the traditional injection anesthetic in

Laser Exposure of Unerupted TeethAli Asgari, D.D.S.; Barry L. Jacobson, D.M.D.; Manisha Mehta, D.M.D.; John L. Pfail, D.D.S.

performing the procedure. Although noteffective in every situation, with proper caseselection and repeated practice, the lasercan yield excellent results in obtaining laseranesthesia.

The first setting of 0.25 W with 10%air and no water was used while slowly out-lining the area of exposure. The proper dis-tance can be gauged by evaluating thewhite chalky outline as the laser begins toexcise the tissue. Excessive darkening of thetissue should not be seen this early on inthe procedure.1-5 The setting was thenincreased to 0.5 W with 10% air and nowater and the same outline followed. Third,0.75 W was used with 10% air and nowater. This is done to achieve anesthesiaand to serve as a guideline for outlining thearea to be surgically exposed.8,10

The tissue begins to darken as thepower increases and the cutting becomesmore aggressive. Once anesthesia is estab-lished, the soft tissue settings of the laserare used at 1.5 W with 7% water and 11%air.3,4 The tip is changed to the G4 tip, whichallows more precise cutting of the tissue.The water is not being used as the cuttingagent in the soft tissue procedures becausethe tissue is already hydrated.11 Thus, the

Figure 1a. Preoperative. Figure 1b. Laser at 0.5W. Figure 1c. Laser at 0.75W. Figure 1d. Laser at soft tissue set-ting; G4 tip.

Figure 2h. Setting at 2.0 W.

Figure 2g. Setting at 0.75W.

Figure 2f. Setting at 0.5W.

Figure 2c. Soft tissue settings. Figure 2d. Postoperative view. Figure 2e. Setting at 0.25W.


water and air settings are decreased fromthe hard tissue setting to act mainly as acooling mechanism as the laser cuts softtissue.8,9 The G4 tip is moved back and forthalong the exposure line already delineatedby the T4 tip. Deeper cuts are made untilthe soft tissue impeding the eruption of thecentral incisors is removed.11

The patient was seen one week postop-eratively and reported no discomfort.3-5 Thecentral incisors began erupting into theirproper alignment.

Case TwoA second case presented with a similar situ-ation of an impacted left central incisor. The8-year-old child with a soft tissue impactedmaxillary left central incisor was brought infor routine care. The child displayed an oth-erwise normal eruption pattern, and thetooth was treatment planned for a surgicalexposure. Along with functional challengesto mastication, the soft tissue-impacted cen-tral incisor was also causing the patient emo-tional distress, as he was being teased by hispeers. The decision was made to expose theincisor to facilitate its eruption into properalignment, treat the patient’s chief complaintand correct his dental malocclusion.

A procedural protocol similar to theone used in Case One was followed,with cer-tain modifications to the laser settings. Theprocedure began again by obtaining soft tis-sue anesthesia. In this situation, we main-tained the same wattage settings, but the airwas increased by 4%. The procedure beganwith the settings at 0.25 W with 14% air andno water, slowly outlining the area of theexposure. The setting was then increased to0.5 W with 14% air and no water, and thesame outline was followed. Finally, 0.75 Wwas used with 14% air and no water, therebycompleting the laser anesthesia technique.The laser was focused and defocused,accord-ing to the patient’s response. Once propersoft tissue anesthesia was obtained, the set-ting was switched to the soft tissue ablationsettings and gentle removal of the tissue wasinitiated.

The G4 tip was used in a continuoussweeping motion, and the proper distancewas established by gauging the colorchange in the tissue to a darker appear-ance. Enough tissue was removed until thecrown of the tooth was exposed. Once thecrown became apparent, cutting wasceased to prevent damage to the underlyingtooth structure.

Figure 1e. One week postoperative. Figure 2a. Preop. Figure 2b. Operative.


ed the need for local anesthesia in manycases. This is of particular importance inpediatric dentistry because it not only doesaway with the anxiety and fear associatedwith receiving an injection, it also removesthe risk of post-anesthetic complications,such as the child accidentally injuring him-self.12

The reasons for the numbing effect ofthe laser have only been postulated at thispoint to result from its transient anestheticeffect, since the laser is not in continuouscontact with the tissue.12 The pulsation ofthe laser allows it to be in contact intermit-tently in rapid sequence, relieving the painstimulus associated with the procedures.

The laser also removes the need for ascalpel in performing these procedures.Although a skilled surgeon can use thescalpel with great accuracy, once an inci-sion is made, there is no digressing fromthe cut.With the laser, the clinician can bet-ter control how aggressively he or she wantsto be in removing tissue.11,12 Therefore, aless experienced clinician can use the laserat a lower setting and cut the tissue moreslowly to reach the same result but at a pacemore fitting to his or her comfort level.11,12

This affords orthodontists, for example,who may not have been trained extensivelyin performing these soft tissue exposures,the opportunity to begin treating casessuch as soft tissue impacted teeth, whichthey encounter on a regular basis.7 This willallow them to expand their practice andhave more control over individual cases.

The hemostatic effect of the laser isalso of note.13 Compared to the traditionalscalpel and suture method of performingsoft tissue dentistry, the laser greatlyreduces the trauma placed on the tissue,thereby expediting the healing time andeffect.7,11 The laser can cauterize the tissueas it cuts, greatly reducing the amount ofheme in the field.11,13 It also negates the

Subsequent to sufficient tissue removal, thetooth will be able to erupt into the properposition unhindered.

Case ThreeThe third case involves a 10-year-oldfemale with both permanent central incisorsand a right lateral incisor still not erupted.The radiograph demonstrated more thantwo-thirds root development and possibleimpaction of the teeth if the roots contin-ued to grow without the teeth eruptingthrough the gingiva. The child presentedwith speech difficulties and, based on herreserved manner in the clinic, psychologi-cal difficulties, arising from her missingfront teeth. The decision was made to exposethe teeth using the above-mentioned lasersettings. In this case, the patient was expe-riencing discomfort from the procedureeven with repeated efforts to obtain laseranesthesia.

Local anesthetic of three-quarters of aCarpule of 3% Carbocaine was used foranesthesia. It was explained to the parentthat further exposure might be required forthe right lateral incisor because of theextent of the impaction. Also, an insuffi-cient amount of space was presented as apossible complication in allowing the later-al incisor to erupt into place. It was alsopossible that maxillary expansion would beneeded in the future.

Within one week of the procedure, thecentral incisors had begun erupting.

The patient was followed up threemonths later. The central had erupted com-pletely. An additional surgical exposure oftooth #7 was completed and within oneweek, the tooth had begun erupting.

DiscussionThe laser offers the clinician a multitude ofadvantages in performing soft tissue den-tistry.11 First and foremost, it has eliminat-

Figure 3a. Preop.

Figure 3b. Operative.

Figure 3c. Immediate postop.

Figure 3d. One week postop.

Figure 3e. Three months postop.

The laser offers the clinician a multitude of advantages in perform-

ing soft tissue dentistry.11 First and foremost, it has eliminated the

need for local anesthesia in many cases.


13. Midda M. The use of lasers in periodontology. CurrOpin Dent 2 1992:104–108.

14. Shulkin NH. The American dental laser: initial patientresponse. Dent Today 1991;10:60-61.

14. Sun G. The role of lasers in cosmetic dentistry. DentClin North Am. 2000; 44(4):831-50.

15. Rossman JA,Cobb CM. Lasers in periodontal therapy.Periodontology 2000 1995;9:150–164.

16. Sarver DM,Yanosky M. Principles of cosmetic dentistryin orthodontics: part 3. Laser treatment for tooth erup-tion and soft tissue problems. Am J Orthod DentofacialOrthop 2005; in press.

17. Ishikawa I, Sasaki KM, Aoki A, Watanabe H. Effects ofEr:YAG laser on periodontal therapy. J Int AcadPeriodontol. 2003;5(1):23-8.

18. Rosenberg SP. The use of erbium,chromium:YSGGlaser in microdentistry. Dent Today 2003;22(6):70-3.

19. Coluzzi DJ. An overview of laser wavelengths used indentistry. In: The Dental Clinics of North America.Philadelphia:WB Saunders. 2000:753-66.

20. Kutsch, VK. The history of dental lasers. Proceedingsfrom the World Clinical Laser Institute. August 2003,Atlantic City, NJ.

21. Passes H, Furman M, Rosenfeld D, Jurim A. A casestudy of lasers in cosmetic dentistry. Curr Opin CosmetDent. 1995:92-9.

2. Eversole LR, Rizoiu IM. Preliminary investigations onthe utility of an erbium, chromium YSGG Laser. J CalifDent Assoc 1995:41-47.

3. Margolis, F. Point of care. J Canad Dent Assoc 2002;70(5): 334-335.

4. Eversole LR, et al. Osseous repair subsequent to surgerywith an erbium hydrokinetic laser system. Proceedings,International Laser Congress, Athens Greece. September1996:25-28.

5. Pick RM, Powell GL.Laser in dentistry. Soft-tissue pro-cedures. Dent Clin North Am 1993;37(2):281-96.

6. Flax HD, Radz GM. Closed-flap laser-assisted estheticdentistry using Er:YSGG technology. Compend ContinEduc Dent 2004;25(8):622, 626, 628-30.

7. Marx I, Op’t HJ. The Er,Cr:YSGG hydrokinetic laser sys-tem for dentistry-clinical applications. So Afr Dent J2002;57(8):323-6.

8. Colvard, MD, Pick RM. Future direction of lasers indental medicine. Curr Opin Periodontol 1993:144–150.

9. Smith TA, Thompson JA, Lee. Assessing patient painduring dental laser treatment. J Am Dent Assoc.1993;124(5):12.

10. Sulieman M. An overview of the use of lasers in gener-al dental practice: 1. Laser physics and tissue interac-tions. Dent Update 2005;32 (4):228-30, 233-4, 236.

11. Stabholz A, Zeltser R, Sela M, Peretz B, Moshonov J,Ziskind D,Stabholz A.The use of lasers in dentistry: prin-ciples of operation and clinical applications. CompendContin Dent Educ 2003;24(12):935-48; quiz 949.

12. Scott A. Use of an erbium laser in lieu of retraction cord:a modern technique. Gen Dent. 2005;53 (2):116-9.

need for sutures in many situations and,as evident in the cases cited here, the post-operative healing is excellent both inpatient comfort and appearance of the sur-gical site.7 The tissue appears pink, stip-pled and healthy one week following aresection of soft tissue and surgical expo-sure of the teeth.7

What the laser has done for patientacceptance of cases and patient apprehen-sion is also significant.4,6,14 With use of theEr,Cr:YSGG laser, a clinician can confident-ly offer a patient a painless surgical proce-dure performed in a short amount of time.This may be a foreign concept to manypatients, but it is the reality of what clini-cians can provide today.4,6,8,14

■

REFERENCES1. Rizoiu IM, Eversole LR, Kimmel AI. Effects of an erbium,

chromium: yttrium, scandium, gallium, garnet laser onmucocutanous soft tissues.J Perio 2001;72 (9):1178-1182.


Abstract

Pemphigus vulgaris (PV) is traditionally viewed as an

autoimmune disease of the skin, but it almost always

involves the oral cavity. It can be fatal if left untreated and

allowed to progress to advanced stages. Early recognition

and intervention are essential for a favorable prognosis.

Since oral lesions represent an initial manifestation of PV,

dentists are in an ideal position to make an early diagno-

sis and initiate treatment. Here we report a case of PV that

was diagnosed in its earliest stage.

PEMPHIGUS VULGARIS (PV) is a chronic autoimmune, intraep-ithelial blistering disease. It is a potentially fatal dermatological dis-order characterized by the production of auto-antibodies directedagainst the epithelium. PV is classically viewed as a disease of theskin, but it almost always affects the oral cavity.1,2 In 50% of cases,the oral cavity represents the initial site of presentation before anyskin or other mucosal lesions arise.3,4 Dentists are, therefore, in theunique position to make the preliminary diagnosis and initiateearly treatment of this life-threatening disease.

Here, we report a case of PV that was detected within weeks ofthe initial onset. The significance of this report rests on the fact thatthe presenting clinical lesions were extremely modest and repre-sentative of an early form of PV.

Case ReportA 58-year-old female presented to the Salivary Gland Center atColumbia University College of Dental Medicine with a three-week

history of burning sensations in the oral cavity. Her medical histo-ry was not significant, and the patient was in good health. At thetime of examination, she was not taking any medications.

The intraoral examination revealed what appeared to be asmall, 2 mm x 4 mm, healing ulcer with an erythematous bordersituated on the attached gingiva in the mandibular premolar area(Figure 1). A second small, 2 mm x 3 mm, irregular mild erythe-matous lesion was found in the mucosal fold of the left retromolararea (Figure 2). Extraorally, there were no signs of any skin ormucosal lesions.

An excisional biopsy of the lesion in the premolar area wasperformed. Sloughing of the mucosal tissue was noted during thebiopsy procedure. Because this desquamation aroused a suspicionof PV, a specimen of the adjacent normal tissue was also harvestedand subjected to a direct immunofluorescence (DIF) study.

The histological examination revealed fragments of stratifiedsquamous epithelium exhibiting a suprabasilar-intraepithelial split(Figure 3).Acantholysis and strips of epithelium demonstrating com-plete detachment from the connective tissues were also observed. TheDIF study was positive and revealed IgG and C3 deposits in theintercellular spaces throughout the epithelium. Both the histologi-cal and DIF results were consistent with a diagnosis of PV.

DiscussionPemphigus can exist alone, or it may be associated with thymoma,myasthenia gravis, lupus erythematous, bullous pemphigoid andsome neoplasias.5,6 Pemphigus has an incidence of about 0.1 to 0.5per 100,000 in the U.S.7,8 It affects all races, but the condition ismore common among Ashkenazi Jews and people of Mediterraneandescent.9 Both sexes are equally involved, usually in the fifth to sixthdecades of life. Rare cases in children and the elderly have alsobeen reported.6,10

Early Manifestation of Pemphigus Vulgaris A C A S E R E P O RT

Keith Da Silva; Louis Mandel, D.D.S.


Pemphigus includes PV, pemphigus foliaceus and paraneoplasticpemphigus, but PV is the most common and represents 80% ofall cases.6

PV is a tissue-specific autoimmune disease. It is characterizedby the deposition of an IgG autoantibody against the desmosomalglycoproteins, desmoglein-1 and desmoglein-3, which are found onthe surface of keratinocytes and act as glue holding the epitheliumtogether.11 The circulating IgG antibodies interfere with cell-to-celladhesion and lead to flaccid blister formation and skin separation.1

The initial causative factors for the production of these autoan-tibodies are unknown, but they may be linked to the presence of ahuman leukocyte antigen (HLA) complex.12 PV can also be inducedby certain medications, such as captopril and penicillamine.13,14

Oral lesions of PV can develop up to four to six months beforeskin lesions appear.15 The most common site in the oral cavity is thebuccal or labial mucosa, with the gingiva and palate being less fre-quently involved. The patient often complains of a persistent sorethroat or burning of the mouth. Clinically, multiple large, flat, vari-able-sized blisters with a red or white necrotic slough and sur-rounding erythema are characteristically seen.1 The lesions aresuperficial and will rupture easily, leaving painful coalesced ulcersthat involve large areas of the oral mucosa. These large denudedareas become susceptible to secondary infection. Gingival involve-ment may take the form of desquamative gingivitis. Pressureapplied to an adjacent area will form a new blister (Nikolsky’s sign),an important diagnostic aid for several bullous diseases.1

PV must be distinguished from other bullous lesions, such aserosive lichen planus, bullous pemphigoid, erythema multiforme,dermatitis herpetiformis, epidermolysis bullosa and Darier’s dis-ease. Definitive diagnosis of PV is dependent upon biopsy results.For histological examination, it is best to obtain tissue samplesfrom intact vesicles of recent onset.When PV is suspected, adjacentnormal tissue is required for DIF study.

The classic histological feature seen in PV is acantholysis, orloss of cell-to-cell contact in the epithelial layer. In PV, intercellularedema occurs within the epithelium, resulting in widening of theintercellular spaces and formation of suprabasilar blisters.16 Thepathognomonic suspended acantholytic epithelial cells (Tzanckcells) within the suprabasilar blister can also be detected with exfo-liative cytology (Tzanck smear).1

DIF is also necessary for diagnosis of PV. Such a diagnosis isbest obtained by submitting a specimen from an area immediatelyadjacent to the suspected lesion. DIF reveals deposits of linear IgGand C3 on the surface of keratinocytes within the intercellularspaces.17,18 Indirect immunofluorescence can also be used to obtainserum titer values of IgG, which may be proportional to the severi-ty of the disease.1

Early diagnosis of PV is paramount to successful treatment. Inour case, a modest healing ulcer of unknown etiology was found,

Figure 1. Healing ulcer with erythematous border situated on attached gingiva(black arrow).

Figure 2. Mild erythematous lesion observed in mucosal fold (white arrow).

Figure 3. H&E stain of specimen reveals fragments of stratified squamous epitheliumexhibiting suprabasilar-intraepithelial split. Tzanck cells are indicated by black arrow.

prompting the decision to biopsy. It was only during the biopsy pro-cedure that the sloughing of tissue was noted and PV suspected.

Improved OutcomePV was once associated with a high morbidity rate. However, theadvent of systemic corticosteroids and immunosuppressive therapyhas reduced the mortality rate to below 10%.4,19 Treatment of PV isdesigned to inhibit production of the aggressor antibodies. The initialtreatment involves administering high doses of a systemic corticos-teroid such as prednisolone.7 Once the initial lesion has disappeared,the dose of corticosteroids can be tapered,until a maintenance dose isachieved. When the initial systemic dose is not sufficient, adjuvantimmunosuppressives, such as cyclophosphamide, azathioprine andmycophenolate mofetil, are added for their steroid sparing effect.7 Theneed for high systemic doses of corticosteroids can also be reducedwith the additional use of topical corticosteroids in the form ofmouthrinses or ointments.

When PV is severe and unresponsive to standard corticos-teroid and oral immunosuppressive agents, pulse therapy withlarge doses of intravenous methylprednisone or cyclophos-phamide may be required.4 Plasmapheresis or high-dose intra-venous immunoglobulin therapies have also been shown to be


effective and may be considered as alternatives.4,7,20 The requiredduration of systemic immunosupression is variable and unclear.

The chances of achieving complete remission are much higherwhen the initial presentation is mild and there is an early and rapidresponse to treatment.4 As in our case, the recognition of an earlylesion and subsequent initiation of treatment resulted in a favor-able prognosis.

ConclusionPemphigus vulgaris is a rare autoimmune mucocutaneous blister-ing disease that can be fatal if left unmanaged. The characteristicdesquamative blistering lesion and the appearance of skin andother mucosal lesions represent advanced stages of PV. In order toprevent morbidity and reduce mortality, early recognition and ther-apeutic intervention are essential.

Since PV has an initial oral manifestation, dentists are in anideal position to make an early diagnosis, therefore the need to biop-sy all suspicious lesions in the oral cavity that may resemble PV. ■

REFERENCES1. Weinberg MA, Insler MS, Campen RB. Mucocutaneous features of autoimmune blister-

ing diseases. Oral Surg Oral Med Oral Path Oral Radiol Endod 1997;84:517-34.2. Scully C, Challacombe SJ. Pemphigus vulgaris: update on etiopathogenesis, oral mani-

festations and management. Crit Rev Oral Biol Med 2002;13:397-408.3. Stoopler ET, Sollecito TP, DeRossi SS. Desquamative gingivitis: early presenting symp-

toms mucocutaneous disease. Quint Int 2003;34:582-586.4. Robinson NA, Yeo JF, Lee YS. Oral pemphigus vulgaris: a case report and literature

update. Ann Acad Med Singapore 2004;33:63-68.5. Ben Lagha N, Poulesquen V, Roujeau JC,Alantar A, Maman L. Pemphigus vulgaris: a case

based update. J Can Dent Assoc 2005 Oct;71:667-72.6. Mahajan VK, Sharma NL, Sharma RC, Garg G. Twelve-year clinico-therapeutic experience

in pemphigus: a retrospective study of 54 cases. Int J Dermatol 2005 Oct; 44:821-8277.7. Yeh SW, Sami N, Ahmed R. Treatment of pemphigus vulgaris: current and emerging

options. Am J Clin Dermatol 2005;6;327-242.8. Fellner MJ, Sapadin AN. Current therapy of pemphigus vulgaris. Mt. Sinai J Med 2001;

68:268-78.9. Thivolet J, Jablonska S. Bullous disorders: from histology to molecular biology. Clin

Dermatol 2001;19:538-543.10. Berger BW, Maler HS, Kantor I. Pemphigus vulgaris in 3 ½-year-old baby.Arch Dermatol

1973;107:433-434.11. Amagai M. Desmoglein as a target in autoimmunity and infection. J Am Acad Dermatol

2003;48:244-252.12. Ahmed AR, Mohimen A, Yunis EJ, Mirza NM, Kumar V, Beutner EH, Alper CA. Linkage

of pemphigus vulgaris antibody to the major histocompatibility complex in healthy rel-atives of patients. J Exp Med 1993; 177:419-24.

13. Kaplan RP, Potter TS, Fox JN. Drug-induced pemphigus related to angiotensin-convert-ing enzyme inhibitors. J Am Acad Dermatol 1992; 26:364-645.

14. Korman NJ, Eyre RW, Zone J, Stanley JR. Drug-induced pemphigus: autoantibodiesdirected against the pemphigus antigen complexes are present in penicillamine andcaptopril-induced pemphigus. J Invest Dermatol 1991; 96:273-6.

15. Siegel MA, Balciunas BA, Kelly M, Serio FG. Diagnosis and management of commonlyoccurring oral vesiculoerosive disorders. Cutis 1991;47:39-43.

16. Hashimoto K, Lever WE An electron microscopic study of pemphigus vulgaris of themouth and skin with special reference to the intercellular cement. J Invest Dermatol1967; 48:540-52.

17. Jordon RE. Direct immunofluorescent studies of pemphigus and bullous pemphigoid.Arch Dermatol 1971; 103:486-90.

18. Kim YH,Geoghegan WD,Jordon RE.Pemphigus immunoglobulin G subclass autoantibodies:studies of reactivity with cultured human keratinocytes. J Lab Clin Med 1990;115:324-31.

19. Lever WF, White H. Treatment of pemphigus with corticosteroids: results obtained in 46patients over a period of 11 years. Arch Dermatol 1963;87:12-26.

20. Ahmed AR, Dahl MV. Consensus statement on the use of intravenous immunoglobulintherapy in the treatment of autoimmune mucocutaneous blistering diseases. ArchDermatol 2003;139:1051-1059.

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Abstract

An accident that can occur during endodontic treatment is

perforation, which adversely affects the prognosis of the

teeth. A restorative material should be easy to use, non-

resorbable, biocompatible, esthetically pleasing, and

should provide a complete seal. Mineral trioxide aggre-

gate (MTA) is a relatively new material that is being used

successfully to repair perforation. The purpose of this

study was to perform a clinical and radiographical evalu-

ation of the success rate of root perforation repairs using

mineral trioxide aggregate. Based upon the results of this

study, MTA is a suitable material for root perforation repair

and can be used confidently.

ONE OF THE EVENTS that occurs during endodontic treatment isstrip and forcal perforation. Ingle1 showed that the second greatestreason for treatment failure was related to root perforation.However, these operative errors accounted for only 9.62% of theunsuccessful cases.

According to Seltzer’s study,2 if the perforated region can beclosed quickly, so that infection and packing do not intervene, there

is a chance for regeneration of the periodontium everywhere exceptover the perforated region. Therefore, a material with appropriateseal ability with no cytotoxic effect should be considered.

Variables affecting the long-term prognosis of perforationsinclude location of the defect relative to the crestal bone; lengthof the root trunk; accessibility for repair; size of the defect; pres-ence or absence of a periodontal communication to the defect;time lapse between perforation and repair; the sealing ability ofthe restorative material; and subjective factors, such as technicalcompetence of the dentist and the attitude and oral hygiene ofthe patient.3,4

Balla5 and Eldeeb6 explained that inflammation in the perfo-rated area may be due to the inadequate sealing ability of the repairmaterials. A restorative material should be easy to use, non-resorbable, biocompatible, esthetically pleasing, and should pro-vide a complete seal.7

Perforation defects may be repaired by nonsurgical or surgicaltechniques.8 Surgical alternatives are hemisection, bicuspidization,root amputation and intentional replantation. The materials com-monly employed to repair perforations include: cavit,9 zinc oxideeugenol (ZOE),3 amalgam,6 super-EBA,10 tricalcium phosphate,11

calcium hydroxide,12 gutta-percha,13 IRM14 and glass ionomer.15

Mineral trioxide aggregate (MTA) is a material that was intro-duced in 1993.14,16 It is a hydrophilic powder that sets when in con-tact with moisture.

Clinical and Radiographic Evaluation of Root Perforation Repair Using MTA

Jamileh Ghoddusi, D.D.S., M.Sc.; Azadeh Sanaan, D.D.S.; Fatemeh Shahrami, D.D.S., M.Sc.


In 1993, Lee et al14 tested amalgam, IRM and MTA for repair ofexperimentally created root perforations. The result showed thatthe MTA had significantly less leakage than IRM or amalgam.

In 1995, Torabinejad et al17 investigated the marginal adapta-tion of MTA as a root-end filling material compared with super-EBAand IRM. Statistical analysis of data comparing gap sizes betweenthe root-end filling materials and their surrounding dentin showsthat MTA had better adaptation than super-EBA and IRM.

In 1995, another study was done by Torabinejad et al.8 Theycompared the antibacterial effects of amalgam, ZOE, super-EBAand MTA on facultative bacteria and seven strict anaerobic bacte-ria. Results showed that amalgam had no antibacterial effectagainst any of the bacteria tested in this study. MTA had an antibac-terial effect on some of the facultative bacteria and no effect on anyof the strict anaerobic bacteria. ZOE and super-EBA pastes hadsome antibacterial effects on both types of bacteria tested.

In 1997, Torabinejad et al19 examined the periradicular tissueresponse of monkeys to MTA and amalgam as root-end fillings. Theresults showed no periradicular inflammation adjacent to five of sixroot ends filled with MTA; also, five of six root ends filled with MTAhad a complete layer of cementum over the filling. In contrast, allroot ends filled with amalgam showed periradicular inflammation,and cementum had not formed over the root-end filling material,although it was present over the cut root end. Based on theseresults, MTA was recommended as a root-end filling material.

In 1998, Sluyk et al20 evaluated the setting properties andretention characteristics of MTA when used as a forcation perfora-tion repair material. The results showed that MTA resisted dis-placement at 72 h to a significantly greater level than at 24 h. Whenslight displacement occurred at 24 h, the material demonstrated theability to re-establish resistance to dislodgement from the dentinwall. The presence of some moisture in the perforation duringplacement was advantageous in aiding adaptation of MTA to thewalls of the perforation, but there was no significant difference inMTA retention when a wet or dry cotton pellet was placed in thepulp chamber during the setting time.

In 1999, Schwartz et al21 presented five cases in which MTA wasused to manage clinical problems. These included vertical rootfracture, apexification, perforation repair and repair of a restorativedefect. In each case, MTA allowed bone healing and elimination ofclinical symptoms. It allowed the overgrowth of cementum andperiodontal ligament. Because of these results, MTA may be anideal material for certain endodontic procedures.

In 2001, Holland et al22 observed the healing process of inten-tional lateral root perforation repaired with MTA. Results showedno inflammation and deposition of cementum over MTA in themajority of the specimens. In the 180-day period, sealapex controlgroups exhibited chronic inflammation in all the specimens andslight deposition of cementum over the material in only three casesof 48 teeth. In conclusion, MTA exhibited better results than thecontrol group.

In 2001 Roda,23 in 2002 Joffe,24 and in 2003 Hembrough et al25 evalu-ated the clinical success rate of root perforation repair using MTA.Results showed that MTA sealed the perforation region successfully.

In 2004, the clinical success rate of MTA was evaluated byMain et al.26 They showed that it provides an effective seal perfora-tion for teeth that would otherwise be compromised.

The purpose of the study described here was to ascertain aclinical and radiographical evaluation of the success rate of rootperforations using MTA.

Method and MaterialsIn this clinical trial study, the subjects were people who werereferred to Mashad Dental School with the primary diagnosis ofperforation. After clinical and radiographical examination, theincluding criteria were: presence of forcal or strip perforation; loca-tion of the perforation under the alveolar crest; absence of a largeperforation; no periodontal disease; and presence of mechanicalperforation. Finally,28 patients were selected. The results of theexamination were collected from evaluation forms.

The treatment was done in either one or two steps. The teeththat had been perforated for one week or less were treated by theone-step treatment, using MTA (Pro Root, Dentsply, Tulsa, OK). Teeth thathad been perforated for more than one week were treated with atwo-step treatment; the first step consisted of using calciumhydroxide, and in the second step, MTA was used. After treatmentin both groups, a wet cotton pellet was placed over the MTA, and theteeth were restored.

The treated teeth were followed up after 6 to12 months. Theseteeth were evaluated clinically and radiographically to examine thehealing process. Three radiographs were examined for each tooth.The first radiograph was the preoperative film, exposed beforerepair of the perforation defect. The second radiograph was thefilm exposed immediately after repair of the perforation. The thirdradiograph was the follow-up film taken at least six months afterthe repair procedure.

The results were recorded noting the presence or absence of aperiradicular lesion.A lesion was defined as any radiolucency adja-cent to the repair site that exceeded double the width of a normalperiodontal ligament space. All 28 cases were also clinically evalu-ated to determine the presence or absence of a periodontal defect inthe area of the perforation. Periodontal pocket measurements werenoted from the follow-up examination. All evaluations were doneby two endodontists.

Finally, according to the negative or positive response tothe treatment, the teeth were categorized into three groups asfollows:1. Successful. The periapical or forcal radiolucency was eliminat-

ed or became smaller and the clinical signs were eliminated.2. Unsuccessful. The periapical or forcal radiolucency became

larger or remained unchanged and the clinical signs were noteliminated.

0

20

40

60

80

100

Graph 2: Frequency of Response to Treatment

Successful Unsuccessful Undetectable


3. Non-defined. The clinical signs were eliminated but the peri-apical or forcal radiolucency remained unchanged.

ResultsThis study was descriptive. The rate of abundance of each groupwas described by the graphs. In this study, the patients werearranged into four groups. The majority of cases fell in the 20-to-29-age group. The teeth, based on their type, were categorized in sixgroups of upper and lower incisors, premolars and molars.According to the radiographical signs before treatment, 64.3% ofthe subjects had radiolucency before treatment, 10.7% were nor-mal, and 21.4% had widening of PDL. The clinical signs beforetreatment are charted in Graph 1. The postoperative radiographiccondition after the 6- to 12-month follow-up period is summarizedin Table 1, which shows that 82.1% of cases were repaired. In allcases, the clinical signs and symptoms were eliminated.

According to Graph 2, 92.9% of cases were placed in the suc-cessful group. Figures 1-3 demonstrate preoperative, postoperativeand follow-up radiographs of one of the treated cases.

DiscussionRoot perforation is an undesirable accident that can occur at any stageof root canal therapy. It includes apical, forcal and strip perforation.Much research has been done on the sealing materials used on perfora-tions.The factors affecting the repair process include the location of theperforation,the time lapse before obturation of the perforation,and thesealing ability and biocompatibility of the repair materials.3 Manymaterials have been used to repair perforations, such as IRM,14 ZOE,3

cavit,9 amalgam,6 calcium hydroxide,12 super-EBA10 and glass ionomer.15

The last recommended material was MTA, which was first usedin 1993.14,16 There have been more animal and in vitro investigationsof MTA than human studies of this material. The cervical or forcalperforations, because of their oral communication, had the worseprognosis in comparison with apical or middle root perforations.3

The main reason to control perforations is to limit the inflam-matory process and to promote PDL attachment. Each material ortechnique has its own characteristic that should be considered inclinical use. Based upon the many investigations of perforationrepair that have been done, MTA was introduced as a suitable mate-rial. The results of this study, in comparison with the results ofother investigations, showed a remarkable increase in positiveprognosis in perforated teeth that were repaired with MTA.

0

10

20

30

40

50

Graph 1: Frequency of Sign and Symptom Before Treatment

Normal Pain & Swelling Pain& Fistol

T A B L E 1Frequency of Radiographic Sign After Treatment

Frequency

Radiography Number Percent

Normal 3 10.7

Widening of PDL 6 21.4

Radiolucency 18 64.3

Undetectable 1 3.6

Figure 1. Radiograph before treatmentshows radiolucent lesion in furcation.

Figure 2. Radiograph after treatment. Figure 3. Radiograph one year aftertreatment shows healing.


In our study, 28 teeth in different patients that had had forcal or stripperforation were selected. Of these 28 teeth, 26 cases in which clinicalsigns and symptoms that appeared before treatment were eliminatedcompletely and the radiolucency was smaller or repaired completelywere defined as successful. One case had failure in treatment. In thiscase, there were no clinical signs or symptoms before and after treat-ment, but the radiolucent area became larger. In fact, it seems that thecase selection was wrong because the perforation area in this toothwas so large.Also, one tooth was considered to be a non-defined casebecause of the superimposition of anatomic landmarks on the perfo-ration region.As a result, we could not investigate this area.

Finally, this study showed that MTA is a very suitable materialfor root perforation repair and increases the root prognosis signif-icantly. In 1995, Pitt Ford et al27 examined MTA as a perforationrepair material. In this animal study, MTA was compared withamalgam, and the results showed MTA was a suitable material forrepair of root perforations. In 1998, Nakata et al28 evaluated the abil-ity of MTA and amalgam to seal forcal perforations in extractedhuman molars using an anaerobic bacterial leakage model. Theresults showed that MTA was significantly better than amalgam inpreventing leakage of F. nucleatum in forcal perforations repair.

In 2001, Holland et al22 observed the healing process of inten-tional lateral root perforation repaired with MTA. It was an animalstudy and the results introduced MTA as a suitable perforationrepair material, too. In 2002,Weldon et al29 longitudinally comparedthe ability of MTA and super-EBA to seal forcation perforation.This study was done on extracted human teeth. In this study, MTAsealed perforations very well.

In 2004, Main et al26 evaluated the clinical success rate of MTAin root perforation repairs. In this study, 16 cases were examined.Five were cases of lateral perforation; five were cases of strip perfo-ration; three were cases of forcal perforation; and three were cases ofapical perforation. In Main’s study, like our study, the teeth had noperiodontal disease. Nine cases had radiolucency and seven caseshad no lesion before treatment. Finally, after the follow-up period, allcases showed no lesion in the perforation area. In fact, this studyshowed the suitability of MTA in sealing root perforations, too. In2005, Bargholz30 suggested a resorbable collagen material for rootperforation repairs. The author claimed that the matrix reconstruct-ed the outer root shape and facilitated the MTA adaptation.

Conclusion and SuggestionsThe results of this study showed that MTA is a suitable material forroot perforation repair and can be used confidently. Therefore, theprognosis of the perforated teeth that were repaired with MTAincreases significantly. The case selection for perforations repair isimportant. The location and size of the perforation, the tooth situ-ation, the existence or absence of periodontal disease and accessi-bility to the perforation area are very important in case selection.Finally, further histological investigations with longer follow-upperiods seem to be necessary. ■

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