laserinternational magazine of laser dentistry12012

i s sn 2193-4665 Vol. 4 • Issue 1/2012

| overviewLaser treatment of dentine hypersensitivity

| industry reportBleaching: New approaches to a traditional minimally invasive therapy

| meeting13th WFLD World Congress in Barcelona

The universe at your fingertips.

TouchWhiteTM Laser Assisted Tooth Whitening A perfect white smile now faster and safer than ever before

• Utilizing the unique laser tissue interaction of the Er:YAG laser wavelength and Fotona's VSP pulse mode• Up to 10 times shorter treatment times• Safer - no unnecessary thermal burden on the tooth or pulp• More comfortable for patients while achieving the same or better whitening efficacy• Any bleaching gel color can be used• Perfect, natural looking results after one single treatment

9081

2/1.

0

ww

w.li

ghtw

alke

rlase

r.com

ww

w.fo

tona

.com

Available only with

Fotona_A4_laser_intern112.pdf 1Fotona_A4_laser_intern112.pdf 1 05.03.12 14:0205.03.12 14:02

editorial I

I 03laser1_2012

_It’s hard to believe that already two years have passed since we said Goodbye in Dubai. Itseems time has passed faster and faster, maybe because more and more dental events are on dis-play. Today, hardly anybody is able to visit all the conferences and congresses which are offered.

It’s all the more pleasing to know that certain conferences like the WFLD congress have main-tained a permanent place in your agenda. Looking at the high numbers of poster and abstractsubmissions, one can estimate that lasers in dentistry are a topic more relevant than ever.

The active participation of the largest manufactures of dental lasers as sponsors and ex-hibitors, along with the high number of laser manufacturers in general who partake in the exhi-bition, also has a high impact on the congress: visitors and participants benefit from the oppor-tunity to see different laser systems in exhibitions, workshops or live demonstrations.

Last but not least, the cultural aspects of the congress venue, the city of Barcelona, are worthundertaking a trip to the upcoming WFLD Congress. Springtime in the streets of Barcelona, asunset dinner with friends on the shore of the Mediterranean Sea, the visit of historical muse-ums, all combined with lectures, workshops and seminars of the congress, will make this eventunforgettable.

On part of the Laser Journal I send my best wishes to the organizers, the board of the WFLD,the speakers and all participants for an inspiring and successful conference.

Prof Dr Norbert GutknechtEditor-in-Chief

Welcome to the WFLD World Congress in Barcelona Prof Dr Norbert GutknechtEditor-in-Chief

I content _ laser

04 I laser1_2012

I editorial

03 Welcome to the WFLD World Congress in Barcelona| Prof Dr Norbert Gutknecht

I research

06 Laser in oral surgery and medicine| Antonio Batista-Cruzado et al.

10 Influences on the treatment of recurrent aphthous ulcerswith the Nd:YAG laser| Dr Iris Brader

14 Treatment of chronic periodontitisby laser and LED-PDT light| Dr G. Karakitsos

I overview

20 Laser treatment of dentine hypersensitivity| Dr Ute Botzenhart et al.

I case report

26 The management of pyogenic granulomawith the 980 nm diode laser| Dr Merita Bardhoshi

I industry report

28 Bleaching: New approaches to a traditional minimallyinvasive therapy| Dr Kresimir Simunovic et al.

34 Effective treatment of periodontal problem areas| Prof Frank Liebaug

I education

38 Laser-assisted Pediatric Dentistry| Dr Gabriele Schindler-Hultzsch

44 The Mundus ACP Program: aiming for a brighter future| Prof Dr Norbert Gutknecht

46 11th “MSc in Lasers in Dentistry” class graduatesat RWTH Aachen University| Dajana Klöckner

I meetings

42 13th WFLD World Congress in Barcelona| Dr Antoni España

47 International events 2012

I news

40 Manufacturer News

48 News

I about the publisher

50 | imprint

page 38 page 42 page 44

page 14 page 28 page 34

Cover image courtesy of Fotona d.d., www.fotona.com.Artwork by Sarah Fuhrmann, OEMUS MEDIA AG.

FASCINATION OFLASER DENTISTRYFOR EXPERTS AND BEGINNERS

MAIN SPONSOR

ORGANIZATION/REGISTRATIONOEMUS MEDIA AGHolbeinstraße 2904229 LeipzigTel.: +49 341 48474-308Fax: +49 341 48474-390event@oemus-media.dewww.dgl-jahrestagung.dewww.startup-laser.de

FURTHER INFORMATION

laser 1/12

OFFICE STAMPPLEASE FAX THIS FORM+49 341 48474-390

Further information about:

❏ LASER START UP 2012 ❏ 21st ANNUAL CONGRESS OF THE DGL e.V

September 7–8, 2012, Leipzig, Germany

NAME/E-MAIL

SEPTEMBER 7–8, 2012//LEIPZIG//HOTEL THE WESTINLEIPZIG, GERMANY

_Introduction

The laser has been used in the field of oral sur-gery for a wide range of indications. In this article,we focus on its surgical uses. The success of the sur-gical treatment of lesions in the oral cavity dependsgreatly on knowledge of the aetiology and histol-ogy of the lesion. There are pathologies that can betreated with laser, such as cancer sores and hyper-keratosis. Others, like candidiasis, cannot be treatedwith laser. Furthermore, laser has quickly become apredictable and favourable treatment modality forleukoplakia, haemangioma and epulis.

_In vitro studies

There have been only few in vitro studies on theapplication of laser in oral surgery. For example, thestudy by Leco Berrocal et al.1 explored the power ofEr:YAG laser sterilisation on dental structures anddental roots in particular. Microbiological culturesindicated lower growth of bacteria after increased

energy irradiation, correlating higher energy irra-diation with a greater sterilising effect of theEr:YAG laser.

_In vivo studies on animals

One of the most important contributions to re-search in the period studied is that by Silvestri et al.2

It describes the possibility of avoiding the develop-ment of a third molar via laser treatment. The use ofa diode laser (20 W) in the development area of thethird molar in newborn rats was able to halt the de-velopment of the tooth by 80 % with only few side-effects.

Silvestri et al.2 also applied this model to dogs.They employed a diode laser at either 20 W or 100 W in the formation area of the molar at the ageof six to seven weeks when it begins to form. Inthose places where 20 W was applied, the molarcontinued its development, but this developmentwas halted at 100 W. These findings indicate new

I research

Laser in oral surgeryand medicineAuthors_Antonio Batista-Cruzado, Daniel Torres-Lagares, Blanca Moreno-Manteca, Gerd Volland,

Patricia Bargiela-Perez, Martin Jorgen & Jose-Luis Gutierrez-Perez, Spain

06 I laser1_2012

avenues to be investigated with application to hu-mans.

Lasers have already been used satisfactorily forthe treatment of various diseases in animals. Forexample, Lewis et al.3 addressed stomatitis in a catwith a CO2 laser. Kovács et al.4 removed prolifera-tive inflammatory eosinophilic granulomatosisfrom a cat’s tongue with a diode laser. This helpedthem to control bleeding, which had been impos-sible before owing to the high number of bloodvessels in the area.

_In vivo studies on humans

Wound healingSeveral new studies have added to the body of

recent research on surgical scarring owing to lasertreatment. Jin et al.,5 for example, analysed thehealing of incisions made by scalpels and diodeand Er,Cr:YSGG lasers in the mucosa of guinea pigsfrom both a histological and immunohistochemi-

cal perspective. During the healing process, theydetected similar changes in the two groups in thestudy overall. However, they identified TGF-� 1 aslower in the scalpel wounds on the first post-op-erative day than in the laser wounds. At sevendays, the TGF-� 1 level was high in the scalpelgroup only. Therefore, they concluded that thehighest tissue damage occurred in the woundsmade by the diode laser, although they consideredit a good cutting device for oral mucosa.

Yamasaki et al.6 studied coagulative necrosis inthe gingiva of rats produced by irradiation with aCO2 laser in pulsed mode and at low power. Thestructural characteristics of the injury and thesubsequent healing process were examined interms of histology, immunohistochemistry and

electron microscopy. The study suggested that co-agulative necrosis produced by the CO2 laser doesnot alter healing, but it promotes its steadyprogress and subsequent tissue remodelling.

A similar study was conducted by D'Arcangeloet al.,7 who examined the effects of scalpel versusdiode laser treatment (808 nm, 4 and 6 W) with re-gard to the expression of eNOS and iNOS from animmunohistochemical perspective. At the histo-logical level, the results partly agreed with the re-sults of Jin et al.5 and partly with Yamasaki et al.,6

given that the group with the worst healing wasthat treated with the diode laser (6 W). The results,however, were also similar to those of the scalpeland the diode (4 W) group. Immunohistochemi-cally, the concentrations of eNOS and iNOS weregreater initially than seven days after the treat-ment in the laser group.

Demir et al.8 studied the influence of low-levellaser therapy (LLLT) on the healing of the oral mu-cosa. They applied LLLT to wounds inflicted byscalpel and laser, noting improved clinical scarringin both of the groups when using LLLT. A histolog-ical analysis showed an improvement in epitheli-sation when LLLT was applied.

Finally, the study by Seoane et al.9 is notewor-thy, in which the thermal damage and the histo-logical types resulting from the use of laser are rel-evant to decision-making regarding biopsies. Thisstudy examined the wounds caused by the CO2laser in 25 Sprague rats, assigned randomly to fivegroups: four pilot groups in which glossectomieswere performed using a CO2 laser (3, 6, 9 and 12 W); and one control group treated with ascalpel. Samples were prepared, then stained and

research I

I 07laser1_2012

I research

Fig. 1_Histological section of the

bone: very small zone of necrosis,

approximately 12 µm. Er:YAG

application (200 mJ, 10 Hz, 400 µs,

pulse, with spray).

Fig. 2_Histological section of the

bone: very small zone of necrosis,

approximately 11 µm, osteoblasts

are not altered. Er:YAG treatment

(200 mJ, 10 Hz, 100 µs, pulse,

with spray).

a double-blind study conducted on them by twopathologists. Cellular and nuclear polymorphism,nuclear aberration and the loss of intercellular ad-hesion were identified, especially in the basal andsupra-basal layers of the oral epithelium, but nodifferences between the experimental groupswere observed. No histological or structuralchanges were observed in the control group. For allthese reasons, the CO2 laser (3–12 W) should beconsidered to generate epithelial damage whichcan simulate dysplasia. This, in turn, can lead to anunsuccessful therapy.

Bone studiesThere are no larger studies that provide new ev-

idence for the results already mentioned in theprevious section. Pourzarandian et al.10 confirmedthat ostectomies carried out with Er:YAG laser, CO2

laser or a surgical bur resulted in greater revitali-sation of osteoblasts and fibroblasts and morepronounced revascularisation in the tissuetreated with the Er:YAG laser. The study by Martinset al.11 found that the healing of an ostectomy inthe jaw is improved after Er:YAG laser treatmentcompared with wounds inflicted by a mechanicalbur or CO2 laser. For this reason, long-term studiesof 60 to 90 days are needed in order to providemore evidence to support these findings. Accord-ingly, many studies on these issues have been pub-lished in recent years. Other studies, such asRochkind et al.,12 have confirmed the positive ef-fect of LLLT on the healing of bone tissue (see his-tological sections, Figs. 1-3).

_Clinical studies

Soft-tissue surgeryStudies on soft-tissue surgery have investi-

gated heat damage in biopsies, the need for anaes-thetic, post-operative pain, as well as intra- andpost-operative complications with regard toscalpel versus laser treatment. Tuncer et al.13 con-firmed that the CO2 laser produces less damage insoft-tissue surgery than the scalpel. In particular,they found a 50 % reduction in the need for use ofanaesthetic, as well as a 60 % reduction in thenumber of patients who needed analgesic medica-tion post-operatively. No complications were ob-served for either of the two groups, and the authorssuggested that thermal changes had not affectedthe histopathological results. The findings are inagreement with other studies published recently,for example Stübinger et al.14

The study by Matsumoto et al.15 provides furtherfindings concerning soft-tissue surgery. It com-pared the emergence and importance of changesat the margins of the biopsies taken by CO2 laser (incontinuous wave and pulsed mode) and throughelectrocautery. Thermal changes associated withthe biopsy instrument were found in all of the sam-ples, but these changes were more significant inthe electrocautery group and continuous-wavelaser group. Therefore, the authors recommend theuse of the CO2 laser in pulsed mode in order to min-imise changes caused by thermal effects.

Vescovi et al.16 further explored the suitability ofvarious laser types for biopsies. They studied ther-mal changes that can alter the pathological diag-nosis and assessed resection margins in threegroups. Group I consisted of six specimens of hu-man oral mucosa removed using an Nd:YAG laserat a power of 3.5 W and frequency of 60 Hz. GroupII consisted of nine specimens removed via anNd:YAG laser at a power of 5 W and frequency of

08 I laser1_2012

Fig. 1

Fig. 2

research I

30 Hz. Lastly, group III consisted of 11 specimensremoved using a #15c Bard-Parker scalpel blade.Their results indicated that the thermal effect oflaser on biopsies introduced slight changes at theedges of the specimen When the laser was used forincisions exceeding 7 mm and at a lower power andhigh frequency, these results were improved(group I, Nd:YAG—3.5 W, 60 Hz).

Kafka et al.17 explored the application of diodelasers in the treatment of soft-tissue conditionssuch as epulis fissuratum. These study found thatthis kind of laser operates optimally. Similarly,studies that evaluate the treatment of tongue le-sions by diode laser, for example the study by Salehand Saafan,18 come to the same conclusion.

Cancer treatment via CO2 laserAlthough mucoepidermoid carcinoma is pain-

less and usually does not produce metastases orrecur, it must be treated both surgically and withpost-operative radiotherapy. The study by Leong etal.19 advanced the research done so far on the useof laser for the treatment of cancer. They report onthe case of a patient with mucoepidermoid carci-noma at the base of the tongue. The authors ap-plied CO2 laser and achieved very good results.

The changes produced by laser during the sur-gical excision of precancerous lesions and theirpossible influence on accurate diagnosis have beenwidely discussed. Goodson and Thomson present20

169 cases of oral premalignant lesions removed viaCO2 laser and their subsequent monitoring overseveral years. A positive correlation was found be-tween the results of the biopsies and those of thehistological studies of the tissue removed by laser.Furthermore, hidden invasive carcinoma was iden-tified in 15 patients and removed by laser.

In seeking to determine the recurrence of le-sions removed by laser, Hamadah and Thomson21

followed 78 patients whose precancerous or dys-plastic lesions were treated with a CO2 laser over aperiod of at least two years. By the end of this pe-riod, 64 % of the patients were free of the disease,32 % developed recurrent local dysplasia or dys-plasia in new sites and 4 % developed squamouscell carcinoma at sites different from their initialdisease. The margins of the excisions were clear in55 % of the cases. However, 19 % showed mild,21 % moderate and 5 % severe dysplasia in thehistopathological examination. The authors rec-ommend the CO2 laser for the excision of lesions,stating that in their study it allowed for completehistopathological evaluation and resulted in min-imal post-operative morbidity and 64 % of pa-tients free of the disease.

Cancer treatment via photodynamic therapyPhotodynamic therapy (PDT) has demonstrated

efficacy in the treatment of dysplasia and earlyforms of microinvasive oral cancer. Clinical studiessuch as the study by Mang et al.22 support this view.Mang et al.22 present a case of squamous cell car-cinoma of the maxillary gingiva, which was suc-cessfully treated with PDT, sparing the patient sur-gery and radiation therapy.

Similarly, Schweitzer and Somers23 evaluatedthe efficacy of the Photofrin-mediated PDT for thetreatment of diffuse field cancerisation in 30 pa-tients for whom conventional treatment hadfailed. In 80 % of the patients, there was completeremission, and the remaining 20 % showed partialremission. After two years, 11 of the 24 patientswith complete remission were cancer free. PDT isalso a form of cancer treatment suitable for thetreatment of oropharyngeal tumours, either pri-marily or in patients whose previous surgeries orradiotherapies have failed._

Editorial note: To be continued with more treatment op-tions and the final conclusion in the next issue of laser.

Fig. 3_Histological section of the

gingiva: effect of heat accumulation

at the surface, necrosis of about

45 µm. Er:YAG treatment (200 mJ,

10 Hz, 1000 µs, pulse with no spray).

I 09laser1_2012

Prof Dr MSc mult Gerd Volland

Facultad de OdontologíaCirurgia bucalUniversidad de SevillaC/ Avicena s/n Sevilla, Spain

dr.volland@t-online.de

_contact laser

Fig. 3

_Introduction

The Greek word aphthi, which means “burning, toset on fire or to inflame”, was first used by Hippocratesfor the clinical symptoms of recurrent aphthousstomatitis (Ship 2000; Scully 2002). These ulcerationsaffect 5 to 25 % of the general population and in se-lect groups, for example students at examinationtime, prevalence can be more than 50 % (Reichardt2000; Scully 2002). The typical lesion involves self-limited, painful, clearly defined, shallow, round or oval1 to 3 mm ulcers, each with a shallow necrotic centre.They are covered with a yellow-greyish pseudomem-brane and are surrounded by minimally raised mar-gins and an erythematous halo, and they tend to healwithin ten to 14 days. We differentiate between threeforms: minor, major and herpetiform aphthae (Ship2000; Scully 2002; Scully 2003).

The diagnosis is almost entirely made on the basisof clinical criteria and the history of an otherwise usu-ally healthy person. The aetiology is still unclear and it

is probable that it is multifactorial, resulting in a vari-ety of predisposing and immunological factors. Thesemay be provoked by one or several different con-tributing factors and associated conditions. Recur-rent aphthae can also be associated with systemicdisorders (such as Behçet’s disease, Reiter’s syn-drome, gastro-intestinal diseases), drug reactions orimmune disturbances (Scully 2002; Porter 2005).Since there is no conclusive evidence for the aetiol-ogy, the therapy is non-specific and attempts to treatsymptoms (Scully 2002). This can be achievedthrough:

– exclusion of triggers;– physical methods (surgery, laser ablation, cauteri-

sation);– topical agents (local anaesthetics), antimicrobials

(chlorhexidine), corticosteroids, immunomodula-tory agents (prostaglandin E2);

– systemic treatments (corticosteroids, thalidomide);– laser treatment (low-level laser, Nd:YAG in non-

contact mode).

I research

Fig.1a_In this case we see a five

year-old girl. Her grandmother

brought her into our praxis, because

she had been suffering from acute

ulcer pain for five days.

Fig. 1b_The aphthous ulcer was

treated with the described

parameters. On the next day, the girl

was free of pain and the ulcer

was smaller.

Influences on the treatmentof recurrent aphthous ulcerswith the Nd:YAG laserAn initial first clinical investigation—Part I

Author_Dr Iris Brader, Germany

10 I laser1_2012

Fig. 1a Fig. 1b

Systemic treatment should be warranted only inpatients with severe and frequent ulcerations be-cause they may have many severe adverse side-ef-fects.

_Aim of the investigation

Treatment with the Nd:YAG laser may reduce orstop ulcer pain and promote healing, but not in allcases. The aim of this investigation is to determine theextent to which certain factors influence treatmentwith the Nd:YAG laser.

_Method and materials

A total of 61 aphthous ulcers were treated, but only45 could be documented completely. Patients suffer-ing from a painful aphthous ulcer at the time were

chosen to participate in clinical trials. Informed con-sent was obtained. In documenting the cases, we firsttook a complete and detailed patient history using astandardised form, followed by the specific historyand diagnostic investigations of the aphthous ulcer,especially with regard to the following: day of forma-tion; size; location; morphological description; inten-sity of the pain (intense/moderate/none).

In addition, two pictures of the ulcer were taken ateach session. We used an Nd:YAG laser (Pulsmaster1000, ADT) with a 300 µm fibre for treatment. Follow-ing Gutknecht (1999), the applied physical parameterswere a pulse energy of 80 mJ and a frequency of 30 Hz(power setting 2.4 W). The pulse width was 100 µs andthe effective energy density amounted to 113 J/cm2.The irradiation was done in non-contact mode from 10to 2 mm towards the ulcer at a rate of approximately

research I

Fig. 1c_Three days after the

treatment with the Nd:YAG laser the

ulcer had healed.

Fig. 2a_11/05/05: extremely painful

ulcer with a size of 8 x 5 mm.

I 11laser1_2012

Fig. 1c Fig. 2a

Please contact Dajana Mischke

d.mischke@oemus-media.de

AD

I research

Fig. 2b & c_12/05/05 and 13/05/05:

no change in size or pain relief.

Fig. 2d_Ulcer four days after

treatment.

Fig. 2e_Six days after treatment:

scar-like impression.

30 s/cm2. We examined and documented the ulcersevery one and three days (Figs. 1a–c). The effectivenessof the treatment was evaluated according to whetherpatients experienced no or reduced pain and the heal-ing time.

_Case report

A 24-year-old female patient came to us on 11 May2005 with an extremely painful ulcer in the base of hermouth. The patient had no systemic disorders but hadcompromised general health because ingestion hadbeen nearly impossible for days. The patient was a non-smoker.

The aphthae appeared ten days before and she hadsuffered from acute and intense pain for five days (Fig.2a). Swallowing, speaking and even rinsing her mouthwith water caused an intense burning sensation. Thepatient had occasionally had ulcers of this kind in thepast, but normally they healed within three to fourdays. The patient had tried to treat the ulcer withchlorhexidine, but the pain was too intense. Our firsttreatment was the smoothing of the distolingual cuspand application of a topical local anaesthetic(Dynexan, Kreussler). Since there was no change in ei-ther pain or size (Figs. 2b & c), we decided to modify thetreatment and use laser. The irradiation was done asdescribed for 50 seconds. The patient told us by phone

that as early as the afternoon of the same day the painwas reduced. On the next day, she felt no pain at all.Four days later, the re-epithelisation was nearly com-plete (Fig. 2d). Six days after the laser treatment, thetissue appeared to be rough and scarred (Fig. 2e).

The topical drugs used initially (chlorhexidine) hadno or only a limited pain-relieving effect for some min-utes (local anaesthetics) and resulted in no changes insize. After the laser treatment, we obtained sympto-matic relief almost immediately and the patient didnot feel any further pain the following day. Sympto-matic relief is possible also in aphthous ulcers that per-sist for longer periods._

Editorial note: To be continued in our next issue of Laser. A list of references is available from the publisher.

12 I laser1_2012

Fig. 2d Fig. 2e

Fig. 2b Fig. 2c

Dr Iris BraderBernhardtstr.198617 MeiningenGermany

Iris.Brader@t-online.de

_contact laser

Master of Science (M.Sc.) in Lasers in Dentistry

Become a part of the International Dentists‘ Elite! The first accredited M.Sc. programme in dentistry in Germany Career-accompanying postgraduate programme of two years at the University of Excellence RWTH Aachen Combination of lectures, skill training sessions, live ops, tutorials, and practical workshops Internationally accepted and accredited by the German Government, the European Union,

the Washington Accord and the Bologna Process Science-based and practice-orientated on highest national and international level

More information:

AALZ GmbH · Pauwelsstrasse 17 · 52074 Aachen · GermanyTel. +49 - 2 41 - 47 57 13 10 · Fax +49 - 2 41 - 47 57 13 29www.aalz.de · info@aalz.de

The next Master programme starts on 24 September 2012 in Aachen

Lay the Foundations to yoursuccessful Future now!

AALZ_DGL_A4_lasereng112.pdf 1AALZ_DGL_A4_lasereng112.pdf 1 05.03.12 16:1205.03.12 16:12

I research

_Introduction

Periodontitis is a very common disease amongadults, with approximately 80 % having gingivitisand periodontitis, and 65 % showing signs of peri-odontitis.1 It is a major cause of tooth loss in adultsand primarily considered an anaerobic bacterial in-fection, caused by the red complex species. Bacteriawithin a biofilm community, as well as enzymes, en-dotoxins, and other cytotoxic factors from thesebacteria, lead to tissue destruction and the initiationof chronic inflammation.2

The conventional treatment entails the mechan-ical removal of calculus and the micro-organismsthrough scaling and root planning (SRP). Antimicro-bial agents, used systemically or via local drug deliv-

ery, further suppress the periodontal pathogens,thus increasing the benefits of conventional me-chanical therapy. However, this conventional me-chanical treatment of periodontitis is not alwayssufficient. Moreover, the emergence of resistant mi-cro-organisms and a shift in the microflora after ex-tended antimicrobial application limits their effect.Other approaches to the local delivery of antimicro-bial agents have been investigated, including the useof high-energy pulsed lasers and photodynamictherapy (PDT).3

The Nd:YAG laser has been used in dentistry fornearly 20 years, primarily in minor surgery and en-dodontics. Nd:YAG laser energy is absorbed by tis-sues and it is this absorbance that allows surgical ex-cision and coagulation of tissue.4 The 1,064 nmwavelength has a particular affinity towardsmelanin or other dark pigments. Therefore, darklypigmented microbes are more sensitive to this laserand can be eliminated at very low power settingswith no collateral damage to the adjacent tissue.Harris and Yessik5 developed a method for quantify-ing the efficacy of ablation of Porphyromonas gingi-valis in vitro, using two different lasers.

Free-running pulsed Nd:YAG laser systems cangenerate high peak powers, at which the individualpulse power can reach several thousand watts. It al-lows this type of laser to deliver the required energyto the target tissue before the absorbed heat can dis-sipate from the treated area.

_Water-spray cooling

Although no comparative studies have been con-ducted on the need for water-spray cooling in both

Treatment of chronic periodontitis by laser andLED-PDT lightAn in vivo study

Authors_Dr G. Karakitsos & Dr J. Karakitsos-Kurz, Greece

14 I laser1_2012

research I

diode and Nd:YAG laser procedures, water-spray canbe said to be counter-productive from a biophysicalpoint of view. Water is a good heat conductor and re-moves heat, whereas a thermal effect is desired.Cooling at the tissue surface is associated with therisk of deeper tissue necrosis. Therefore, water-sprayshould not be used in diode laser procedures.

For this reason, this study made use of an Nd:YAGlaser without water and only with air spray.3

_LLLT lasers

The treatment of periodontitis with low-levellaser therapy (LLLT) has not been common to date,and only a limited amount of literature exists. In ablind study by Qadri et al.,6 the clinical parameters,such as probing of the pocket depth, plaque indexand gingival index, were more strongly reduced onthe laser side than on the placebo side, with p < 0.01.The wavelengths used for LLLT have poor absorptionin water, allowing for a penetration depth in soft andhard tissue ranging from 3 to 15 mm. As the energypenetrates tissues, it is scattered by both erythro-cytes and micro-vessels. Because of this, both blooddistribution and the network of micro-vessels in thetissue influence how the laser-light works, muchlike a bio-laser. LLLT lasers do not cut or ablate, butthey use a photobiological process, which can havepositive effects on periodontal healing and pain re-lief. LLLT is optimal for cells in a reduced oxygen en-vironment.7

_Photodynamic therapy

PDT protocols use diode lasers or LED light withwavelengths that range from 635 to 690 nm, com-bined with a photosensitiser to eradicate sub-gingi-val microbes. PDT, which is also known as photo-ra-diation therapy, phototherapy or photochemother-apy, involves the use of a photoactive dye (photo-sensitiser), which is activated by exposure to light ofa specific wavelength in the presence of oxygen. Thetransfer of energy from the activated photosensi-tiser to available oxygen results in the formation oftoxic oxygen species, such as singlet oxygen and free

radicals. The oral cavity is especially suitable forphotodynamic antimicrobial chemotherapy (PACT)because it is relatively accessible for illumination.8

Dye concentration is a very important factor tobe taken into consideration, since it results in a lim-ited production of reactive oxygen (ROS) and re-quires a longer irradiation time. A high dye concen-tration works as an optical filter because of the re-sulting high absorption effect. The present studymade use of a toluidine blue photosensitiser with alow concentration of 0.01 %, ensuring that soft-tis-sue irradiation and hard-tissue staining do not oc-cur.

A semiconductor laser, such as the GaAlAs laserused in this study, has a coherence length of a fewmillimetres. This is very important, since the laserlight produces constructive interference in tissueand consequent speckle formation. In contrast, LEDlight does not create speckles. These LED-lightsources have a spectral width of 30 to 100 nm. LEDreacts with cytochromes in the body. When cy-tochromes are activated, their energy levels in-crease, which stimulates tissue growth and regen-eration.9

_Materials and methods

In January 2011, in Thessaloniki, Greece, 12adults (seven women and five men), with an averageage of 47 years (ranging from 29 to 68 years) wererandomly assigned for treatment of the left or rightside of the mouth. After the second week of thetreatment, two patients had to leave the study be-cause they had used antibiotics. The study was con-tinued with ten patients, six women and four men.The patients were questioned about their systemichealth status, their use of medication and smokinghabits. In all of these cases, the inclusion criteriawere periodontal pockets with probing depthsdeeper than 5 mm, with haemorrhagic findings andclinical signs of inflammation (swelling, secretion,etc.). Those individuals with a medical history of sys-temic disease requiring medication, those who hadundergone antibiotic therapy within a three-month

Figs. 1 & 2_Change in detection

levels of five bacteria from baseline

(0) to one week and two weeks,

to one month, and from one month

to three months post-treatment.

I 15laser1_2012

Fig. 2Fig. 1

I research

Figs. 3–5_Change in detection levels

of five bacteria from baseline (0) to

one week and two weeks, to one

month, and from one month to three

months post-treatment.

period preceding the study, and those with conta-gious diseases, as well as pregnant women and nurs-ing mothers, were excluded.

Periodontal examinationAt baseline, one trained examiner, who was

masked to the test and control groups, measured theclinical periodontal parameters, including BOP(bleeding on probing) and PPD (probing pocketdepth). These were measured with a graded peri-odontal probe (PerioWise, Premier Dental) at sixsites. All teeth, except for the third molars, were reg-istered.

Treatment protocolsThe patients were randomly divided into four

groups, which represented four different treatmentmodalities. At baseline (day 0), the patients assignedto group I received a one-hour session of full-mouthsub-gingival debridement, using a piezoceramic ul-trasonic instrument (Piezon Master 400 with A+ PerioSlim tips, water coolant and power setting at75%; EMS). The patients in group II received SRP withultrasonic full-mouth debridement and then irradi-ation with a GaAlAs low-level laser at 830 nm(DIOBEAM, CMS Dental). The patients in group III re-ceived SRP with ultrasonic full-mouth debridementand then irradiation with a pulsed Nd:YAG laser at1,064nm (Genius). Finally, the patients in group IVreceived SRP with ultrasonic full-mouth debride-ment and then irradiation with the LED-PDT laser(FotoSan, CMS Dental).

Clinical parameter measurementsThe PPD and BOP were measured for each group

before the treatment, as well as one and threemonths post-treatment. Five clinical samples of gin-gival crevicular fluid were obtained from each pa-tient and analysed with the DNA reverse-hybridisa-tion laboratory process in the following order: (i) pre-treatment; (ii) one week after the first laser or LED-light session; (iii) one week after the second laser orLED-light session; (iv) one month post-treatment;and (v) three months post-treatment. A total of 200microbiological samples were taken during the studyperiod.

Laser parameters and lasersThe laser equipment used in this study was an

Nd:YAG laser (1,064 nm), a GaAlAs low-level laser(830 nm) and a LED light (625–635 nm). The lasertreatment was performed by inserting the optical fibre into the periodontal pocket, almost parallel tothe tooth.

The Nd:YAG laser was used with the following set-tings: an average output of 4 W energy per pulse of80 mJ; pulse width of 350 µs and pulse repetition rateof 50 Hz; pulse peak power of 228 W; average powerdensity at the fibre end of 1,415 W/cm2; and peakpower density of 80,600 W/cm2. Laser energy pertreated tooth was 240 J. The fibre diameter was600µs (0.002826 cm2). Only air cooling (+5 scale)was used during irradiation. The time spent on eachtooth was 60 seconds.

The GaAlAs laser was used with the followingpower-intensity settings: the 8 J button was utilisedand energy intensity was 63.5 J/cm2. The buccal,palatal and lingual papillae were treated for 53.3 sec-onds per surface. The irradiated area was 0.25 cm2.

The LED light used in this study had an outputpower of 2,000 mW/cm2. The energy density (J/cm2)was not calculated because the energy was emittednot only from the tip, but also with considerable lat-eral emission. The sites were irradiated from both thebuccal and lingual aspects.

Microbiological examinationSterile paper points (ISO 40) were used for 30 sec-

onds each to harvest sub-gingival plaque. The plaquewas taken from the same site as the gingival crevic-ular fluid samples. After the paper point were col-lected from each quadrant, they were placed in ster-ile transport vials and sent to the laboratory for athorough analysis. The sub-gingival microbiota wereanalysed using the checkerboard DNA-DNA hybridi-sation technique.3 Furthermore, the frequencies ofpositive sites and of sites with colony-forming units≥103 were recorded. The following five micro-or-ganisms were analysed: Aggregatibacter actino-mycetemcomitans, P. gingivalis, Prevotella interme-

16 I laser1_2012

Fig. 4Fig. 3

research I

dia, Tannerella forsythensis and Treponema denti-cola ((AID Diagnostika GmbH, Periodontitis++).

Statistical methodsCommercially available software, such as Graph-

Pad Prism 5 by GraphPad Software, was used for thestatistical analysis. PPD and BOP were the primaryclinical-outcome variables. Mean values and stan-dard deviations (mean ± SDs) for the clinical vari-ables were calculated for each treatment, based onthe subject as the statistical unit. The student’s t-testwas employed for continuous variables (clinicalmeasurements), after the normality of the data dis-tribution had been confirmed.

Similarly, the significance of the difference withineach group, pre- and post-treatment, was evaluatedwith the paired-samples t-test. Differences wereconsidered statistically significant when the p-valuewas less than 0.05.

The post-therapeutic data in each quadrant waschecked against the initial data, using the paired t-test for statistically significant differences. Finally,the data of the quadrants additionally treated withlaser was compared to the data of the convention-ally treated quadrant as part of an unpaired t-test.

_Results

Microbiological resultsAll of the ten patients attended the baseline ex-

amination and the follow-up appointments. In theNd:YAG laser- and SRP-treated group, it must beemphasised that A. actinomycetemcomitans (A.a.)levels were significantly reduced over the entirestudy period. It should also be noted that A.a. wasreduced during the second week of treatment inthe LED PDT- and SRP-treated group. Furthermore,the Gram-negative anaerobic bacteria were signif-icantly reduced in the course of the study in theNd:YAG laser group, in contrast with a lack of re-duction for the other treatment groups. In theGaAIAs laser treated group, the microbiologicalsamples showed an increase from moderate tohigher detection levels. This result is in accordance

with evidence in the literature that the low-levellaser produces bacterial growth.10

Clinical resultsAll treatment groups showed significant de-

creases in PPD and BOP over the three-monthpost-treatment period. Baseline PPD was 4.37 (0.7) mm in the Nd:YAG quadrant, 4.10 (0.37) mmin the GaAIAs laser quadrant, 4.00 (0.4) mm in theLED-PDT quadrant and 4.03 (0.35) mm in the SRPquadrant. After three months of treatment, PPDwas 2.47 (0.32) mm in the Nd:YAG quadrant, 2.62(0.16) mm in the GaAIAs laser quadrant, 2.52 (0.29) mm in the LED-PDT quadrant and 2.92 (0.18) mm in the SRP quadrant. The reduction inPPD was significantly greater in the test groupthan the control group.

Baseline BOP for the Nd:YAG laser quadrant was12.4. It decreased to five after one month and tozero after three months. For the GaAIAs laserquadrant, the baseline was 11.9, and BOP was 2.4after one month and 0.5 after three months. In theLED-PDT quadrant, the baseline was 11.7, and BOPwas 3.7 after one month and 0.8 after threemonths. For the SRP quadrant, the baseline was12.3, and BOP was 4.9 after one month and 2.3 af-ter three months.

For the PPD parameter, no significant differ-ence could be established when comparing thefour treatment methods used in this study directly.For the BOP index, the number of the haemorrhagicpoints clearly decreased in the quadrants treatedwith laser (Nd:YAG or GaAlAs laser) and with LEDPDT, as compared with the one treated conven-tionally (Figs. 1–9).

_Discussion

The results in this study demonstrated that, whencompared with the inflammation seen after non-surgical treatment, additional treatment with theNd:YAG laser, GaAIAs laser and LED-PDT light led tofurther reduction in gingival inflammation. Both thePPD and the number of BOP findings declined more

Fig. 6_Change in PPD from baseline

to one month and from one month to

three months post-treatment in test

and control teeth.

I 17laser1_2012

Fig. 6Fig. 5

in the quadrant in which these additional treatmentswere performed.

The average values of the five microbial speciesthat were investigated in this study were lower in thequadrants treated with Nd:YAG laser and SRP than inthe quadrants that had been treated with GaAIAslaser and SRP, LED PDT and SRP, and conventionalSRP. There were statistically significant differencesin favour of the Nd:YAG laser method, especially inthe first seven weeks. These findings confirm thefindings from the study by Gutknecht et al.,11 whichdemonstrated a reduction of specific micro-organ-isms in periodontal pockets when conventionaltreatment was supported by the use of an Nd:YAGlaser.

Recurrence is reported in several studies and is at-tributed to cross-contamination from non-treatedpockets and/or saliva.12 In the present study, theNd:YAG laser group was found to have a significantreduction in the levels of A.a.

The LED-PDT group also showed a reduction inA.a. levels, although this short-term decline was fol-lowed by a reappearance of the A.a. Both the GaAIAs laser and the LED-PDT groups, with toluidineblue as an adjunct to conventional SRP treatment,showed beneficial effects in clinical parameters likePPD and BOP, in comparison with the conventionalSRP treatment.6 One explanation may be that laserirradiation reduces prostaglandin E2, or that itcauses stimulation of cellular ATP. The GaAIAs laseralso seems to have a stimulating effect on bacterial

growth, confirming similar findings in the scientificliterature.13

However, certain pathogens, such as A. actino-mycetemcomitans and P. gingivalis, are particularlyresistant to the effects of sub-gingival debridement.This has been linked to their ability to invade thepocket epithelium and underlying connective tis-sue.14

_Conclusion

The results of this study prove the positive roleof coherent or non-coherent light irradiation as ad-juncts to SRP in the non-surgical treatment of pe-riodontitis. The ability of the Nd:YAG laser to reducethe levels of oral bacterial pathogens is muchhigher than that of LED PDT. Possibly one very im-portant factor for the success of laser treatment isthe regeneration of periodontal tissue, and it is bestachieved by initially reducing the bacterial load.

LED PDT could be used as an alternative peri-odontal treatment after an initial treatment phasewith the Nd:YAG laser. It should be limited to peri-ods between treatment recalls. The short-term ef-fect of LED PDT is sufficient to prevent a quick bac-terial recolonisation of affected sites, especially inhigh-risk patients._

Editorial note: A complete list of references is availablefrom the publisher.

I research

Fig. 7_Change in BOP findings per

quadrant from baseline to one month

and from one month to three months

post-treatment in test and control

teeth.

Fig. 8_The post-therapeutically

established data in each treated

quadrant was checked with the initial

data for statistically significant

differences with the help of a

paired t-test.

Fig. 9_The data gathered in those

quadrants that were additionally

treated conventionally with the

Nd:YAG laser, GaAlAs laser and LED

PDT was compared with the data of

the conventionally treated quadrant

as a part of an unpaired t-test.

18 I laser1_2012

Dr G. Karakitsos and Dr J. Karakitsos-KurzPrivate Dental ClinicKrithia 1, Dimos Lagada57200 ThessalonikiGreece

Tel.: +30 69 3 666 0135Fax: +30 23 9 405 4458

georgekaraki@yahoo.gr

_contact laser

Fig. 9

Fig. 8Fig. 7

International annualcongress of the dgzi

FAX REPLY+49 341 48474-390Please send me further information on the42nd International annual congress of the DGZI October 5–6, 2012, in Hamburg, Germany.

Office Stamp

laser 1/12

Silver Sponsor:Gold Sponsor: Bronze Sponsor:

SpeakersProf. Dr. Dr. Kai-Olaf Henkel/DEProf. Dr. Dr. George Khoury/DEProf. Dr. Dr. Albert Mehl/CHProf. Dr. Herbert Deppe/DEProf. Dr. Werner Götz/DEProf. Dr. Shoji Hayashi/JPProf. Dr. Andrea Mombelli/CHProf. Dr. Dr. Frank Palm/DEProf. Dr. Suheil Boutros/USProf. Dr. Peter Rammelsberg/DEProf. Dr. Anton Sculean/CHProf. Dr. Dr. Jörg R. Strub/DEProf. Dr. Hans-Peter Weber/US

Prof. Dr. Thomas Weischer/DEPriv.-Doz. Dr. Andreas Bindl/CHDr. Tomohiro Ezaki/JPDr. Daniel Ferrari, MSc/DEDr. Sami Jade/LBDr. Ramy Fahmy Rezkallah/EGDr. Rolf Vollmer/DEDr. Osamu Yamashita/JPZTM Andreas Kunz/DEZTM Tom Lassen/DEZTM Christian Müller/DEMohamed Moataz M. KhamisB.D.S., M.S., Ph.D./EG

Quality driven implantology – On the way to long term success

October 5-6, 2012//Hamburg, Germany//Elysee Hotel

Congress President//Prof. Dr. Dr. Frank Palm/DEScientific Director//Dr. Roland Hille/DE

I overview

Fig. 1_Clinical situation of a patient

with gingival recession. The

occurrence of gingival recession is a

precursor to the loss of cement,

owing to poor oral hygiene, the

exposure of tooth necks and dentine

hypersensitivity.

_Introduction

More than two decades ago, laser applications inthe treatment of dentine hypersensitivity were in-troduced to dentistry. Many clinical studies usingdifferent laser types have been published since. Thisoverview summarises the basic and clinical aspects,including treatment protocols.

_The hypersensitive dental neck

Dentine hypersensitivity is a widespread painfulcondition in dentistry (Orchardson et al. 2006;Schwarz et al. 2002). Unfortunately, this clinicalcondition is often poorly understood (Pesevska etal. 2010). It is important to understand this condi-tion in light of dental therapy because the need fortreatment is increasing (Gerschman et al. 1994;Miglani et al. 2010). Hypersensitivity occurs whentooth necks are exposed. Brannström’s hydrody-namic theory describes these mechanisms. Chemi-cal, osmotic, physical or mechanical stimuli inducemovement of fluid in dental tubules, which acti-vates pain fibres—mainly A-� fibres—at the pulp-dentine border (Brannström 1992). Afflicted pa-tients describe an intense and sharp pain of shortduration that cannot be ascribed to any other formof dental defect or disease (Canadian AdvisoryBoard on Dentin Hypersensitivity 2003). In a hugenumber of cases, these symptoms are triggered bycold and are not related to restorative or cariestherapy. The well-being of patients who suffer fromdentine hypersensitivity is often affected. Dailystimulation, for example eating or teeth brushing,could induce considerable pain (Rösing et al. 2009;Tengrungsun et al. 2008).

Today, more than 30 % of the adult populationof industrialised nations is thought to be affected(Ritter et al. 2006; Gillam et al. 1997), but the actual

prevalence is still unknown (Rösing et al. 2009). Thereported incidence mainly depends on the popula-tion under examination and the methodology ofthe studies, which vary a lot. Middle-aged patientsare most often affected (Al Sabbagh et al. 2004), buta growing number of young persons are affected bydentine hypersensitivity (Sykes 2007). The higherfrequency of hypersensitivity, even in middle-agedadults, could be explained by increasing exposure oftooth necks, which occurs increasingly early on inyoung people (Dowell et al. 1983). The main reasonsfor exposure are erosion, abrasion and attrition.However, erosion is most likely to be the main fac-tor (Addy et al. 1994; Gillam et al. 1997). This comesfrom an increasing awareness of dental hygiene,which has resulted in well-intentioned but incor-rect brushing (Fig. 1). For these reasons, sensitivetooth necks frequently occur opposite the handthat is brushing. The loss of the thin cementumlayer in the tooth-neck area is responsible for morethan 90 % of the hypersensitive surfaces (Orchard-son et al. 1987). As a result, dentine hypersensitiv-ity can be characterised as a tooth-wear phenom-enon (Bamise et al. 2008). Restorations, functionaloverload and bleaching of vital teeth are alsocauses of dentine hypersensitivity (Brannström1992; Jacobsen et al. 2001; Haywood 2002). Nowa-days, one therefore speaks of a multifactorial gen-esis of dentine hypersensitivity associated withtooth wear.

Despite intensive research, the precise physio-logical mechanisms of pain production and trans-mission in the dental pulp have not been suffi-ciently determined (He et al. 2011; Bal et al. 1999;Zhang et al. 1998). The surface texture of dentine,that is the number of open tubules at the root neck,is of great relevance to the process of dentine hy-persensitivity (Absi et al. 1987; Markowitz 1993;Fig. 2). The extent of hypersensitivity depends on

Laser treatment of dentine hypersensitivityAn overview Part I

Authors_Dr Ute Botzenhart, Dr Andreas Braun & Prof Matthias Frentzen, Germany

20 I laser1_2012

Fig. 1

overview I

the number of exposed tubules (Ngassapa 1996).Clinical studies (Narhi et al. 1992) and SEM exami-nations (Absi et al. 1987) have demonstrated thatthe dentine of hypersensitive teeth has a consider-ably higher number of exposed dental tubules(eight times the number) with a considerablygreater aperture (twice the size) compared withteeth with no hypersensitivity symptoms (Absi et al.1987). Since dentine hypersensitivity can occureven after the closure of most of the dental tubules,other factors, like inflammatory mediators, are as-sumed to be involved in nerve stimulation and pain(Narhi et al. 1992; Ngassapa 1996) in addition to thehydrodynamic theory.

_Conventional therapy

Currently, a multitude of desensitising agentsare available on the market. Normally, the thera-peutic mechanism is based upon the hydrodynamictheory. By occluding dentinal tubules, movement offluid should be reduced. Furthermore, the reduc-tion of pulpal pain-nerve fibre firing should con-tribute to reduced sensitivity.

The spectrum of applications ranges fromagents for topical application, dentine adhesives,light-curing primer systems, mucogingival surgeryfor soft-tissue management, conventional fillings,to endodontics as ultima ratio. Topical applicationsare the most important for desensitisation; amongthem are fluorides, potassium and calcium com-pounds, hydroxyapatite, bioactive glass and glass-ceramics, oxalates, glutaraldehyde, formalin andchlorhexidine. These ingredients are mostly foundin toothpastes, mouth rinses, gels, suspensions,varnishes or pastes for topical application. They canalso be applied via chewing gum or iontophoresis.Today, the application of nano-sized particles ofdifferent mixtures is also very popular.

In 1935, Grossman formulated a set of criteriathat desensitising agents are to fulfil. These criteriaare still valid today (Renton-Harper et al. 1992):

– no irritation of pulp tissue;– painless application;– easy to apply;– rapid in effect;– sufficient efficiency;– no side-effects; and– long-term effectiveness.

The predominant number of compounds lead toa rapid resolution of symptoms, but often they areonly short-lived. In most cases, a long-term occlu-sion of dentinal tubules cannot be attained. Thusfar, no desensitising substance or method of appli-

cation has fulfilled all the criteria Grossmann pos-tulated in 1935. There has been a constant im-provement in terms of the available means of treat-ment and active substances, but the reports stilldemonstrate difficulty in relieving the pain (Ro-mano et al. 2011). Until recently, no universally ap-plicable substance was available (Mitchell et al.2011; Tirapelli et al. 2010; Dabahne et al. 1999).

_Laser application

Precipitates and surface coverings disintegrateafter some time, for example owing to the influenceof acid or toothbrush abrasion (Addy et al. 1983).Conventional desensitising treatments had to beapplied repeatedly at regular intervals to ensure adurable analgesia (Gillam et al. 1992; Cuenin et al.1991). The application of laser beams of differentwavelengths and energy levels, alone or in combi-nation with topical application, for example fluo-ride, is an alternative method for the treatment ofdentine hypersensitivity.

_Studies on the effects of laser application

In vitro and in vivo studies document high effec-tiveness rates and comparatively long-lasting painrelief. The most commonly used types of lasers forthe treatment of dentine hypersensitivity alreadydetermined in vivo can be divided into two groups.Those lasers with a lower output power, low-levellasers (He-Ne and GaAlAs diode lasers), are appliedto biostimulation and are distinguishable fromlaser types with a middle-output power, middle-output power lasers, which have the ability to mor-phologically alter dental hard tissue.

The middle-output power lasers include theNd:YAG, Er:YAG laser and CO2 lasers (Dederich et al.1984; Melcer et al. 1985; Featherstone et al. 1987).The effect of these laser types can probably be at-tributed to the sealing of the dentinal tubules, nerveanalgesia and placebo effects. The sealing has beenobserved to be of long-lasting effect, whereas in

Fig. 2_SEM examination of a human

cervical dentinal surface with open

tubules, after experimental removal

of the smear layer with 50 % citric

acid for one minute

(1,000x magnification).

I 21laser1_2012

Fig. 2

I overview

the case of nerve analgesia and placebo effects, theeffects are not durable (Kimura et al. 2000a). De-spite the precise mechanisms of laser action, thelong-term value of laser therapy in treating dentinehypersensitivity is uncertain; current evidence isbased upon a slight superiority compared with con-ventional topical applications (He et al. 2011).

Laser therapy with low-output power has beenapplied to humans since the 1970s and was origi-nally used for wound healing (Kimura et al. 1991,1993, 1997). In the 1980s, the inhibition of inflam-mation (Karu 1988, 1989) and the stimulation ofnerve cells were demonstrated (Kimura et al. 1993;Jarvis et al. 1990).

_Low-level lasers: GaAlAs laser

Thus far, GaAlAs diode lasers of three wave-lengths have been used clinically to treat dentinehypersensitivity: 780, 830 and 900 nm. The 780 nmwavelength has been used with good clinical suc-cess (30 mW in continuous wave mode [cw] and anapplication time of about 0.5 to three minutes;Matsumoto et al. 1985a). The 830 nm wavelengthfor the treatment of dentine hypersensitivity wasfirst described by Matsumoto in 1990. With an en-ergy setting of 20 to 60 mW in cw mode and an ap-plication time of 0.5 to three minutes, the effec-tiveness of therapy was 30 to 100 %, depending onthe energy level (Matsumoto et al. 1990). The effec-tiveness of therapy using the 900 nm wavelengthand an output power of 2.4 mW at 1.2 Hz for 2.5minutes was approximately 73 to 100 % (Kimura etal. 2000b). Yamaguchi et al. (1990) compared theapplication of a GaAlAs diode laser of a wavelengthof 790 nm and an output power of 30 mW and aplacebo in vivo. Significant differences betweenlaser application and the placebo group werefound. At two hours, one day and five days afterlaser application, a significant improvement wasdetected (Yamaguchi et al. 1990). Overall, com-pared with the placebo, an improvement of 60 to22 % was achieved. GaAlAs laser application with amaximal energy output of 60 mW did not damageenamel or dentine surfaces morphologically(Watanabe et al. 1991).

According to another in vitro study, the applica-tion of GaAlAs laser diodes with energy levels of 30 mW (cw, 780 nm), 60 mW (cw, 830 nm) and 10 W (pulsed, 900 nm) did not lead to a significantincrease in the temperature in the dental pulp (Arrastia et al. 1994). Gerschman et al. (1994) ac-complished a clinical double-blind study withGaAlAs lasers compared with a placebo. During thetherapy, the apical and cervical regions of the tooth

were irradiated for one minute; this procedure wasrepeated in one-week, two-week and eight-weekintervals. Dentine hypersensitivity evoked by tactileand thermal stimuli was measured at each controland compared with the placebo group. A significantdifference concerning dentine hypersensitivitywas detected during the analysis. It was thereforededuced that the GaAlAs laser is an effectivemethod for dentine desensitisation (Gerschman etal. 1994).

_Combined application of GaAlAs laserand fluoride

In another clinical study, a laser with an energydensity of 3 and 5 J/cm2 was applied up to six timesin an interval of 72 hours after each application(Marsilio et al. 2003). Dentine hypersensitivity wasmeasured initially after each application, and at 15and 60 days after application. In more than 85 % ofthe teeth treated, an improvement was detected.Side-effects were not observed (Marsilio et al.2003). In a comparative study of GaAlAs laser ap-plication (630–670 nm) at energy levels of 15 mWin contact mode for 20 seconds and fluoride appli-cation (Fluor Protector, Ivoclar Vivadent), signifi-cant and complete relief from pain after three ses-sions was achieved in 86.6 % of the cases comparedwith 26.6 % after fluoridation only (Pesevska et al.2010). The clinical findings of Noya et al. (2004)proved that just a single application of GaAlAs laser(670 nm, 15 mW, 5 J/cm2) yields a statistically sig-nificant reduction in sensitivity to mechanical andthermal stimuli and that two applications areenough to reduce sensitivity to air. No other appli-cation led to any additional benefit (Noya et al.2004).

A significant reduction in VAS scores was alsodetected with laser application for 160 seconds atan energy density of 4 J/cm2 per dental element at24 hours and seven days after application com-pared with a placebo application (Orhan et al. 2010).All teeth remained vital and no adverse effects werefound radiographically, but the results were notsignificantly different from any conventional de-sensitiser (Gluma Desensitizer, Heraeus Kulzer;Orhan et al. 2010).

A combined application of GaAlAs laser lightwith sodium fluoride (NaF) at an energy output of15 mW and density of 4 J/cm2 led to no statisticallysignificant differences between laser applicationand combined laser and fluoridation treatment(Corona et al. 2003).

Whether a combined application of GaAlAs laserand fluoride is effective in treating dentine hyper-

22 I laser1_2012

FOR MORE INFORMATION:Greater New York Dental Mee ng®

570 Seventh Avenue - Suite 800New York, NY 10018 USA

Tel: (212) 398-6922 / Fax: (212) 398-6934E-mail: victoria@gnydm.com

Scien c Mee ng: Friday - Wednesday,

November 23 - 28

Exhibit Dates: Sunday - Wednesday,

November 25 - 28

MARK YOUR CALENDAR

A A N CNever a pre-registra on fee at the Greater New York Dental Mee ng

M H 600 EXH BJacob K. Javits Conven on Center 11th Ave.

between 34-39th Streets (Manha an)

Q New York Marrio Marquis otel

L V D A - N T

L D T H S A V

M TH 350 S PSeminars, ands-on Workshops, Essays & Scien c Poster Sessions as well as

Specialty and Auxiliary Programs

E P V

S P H E F

E N Y C B H V

H !

Sponsored by the New York County Dental Society and the Second District Dental Society

GNYDM_2012_A4_engn.pdf 1GNYDM_2012_A4_engn.pdf 1 20.03.12 17:3420.03.12 17:34

I overview

24 I laser1_2012

sensitivity is questionable. Results are contradic-tory, often masked by placebo effects and highlydependent on laser parameters and the given cir-cumstances for each patient. Both methods oftreatment, GaAlAs laser application and fluorida-tion, are suitable for dentine hypersensitivity ther-apy.

_Biostimulative mechanisms of GaAlAs lasers

The GaAlAs laser mechanism is thought to bebiostimulative rather than effecting morphologicalchanges in dentine. It is assumed that the laser en-ergy is transmitted to the dentine–pulp complex,interacts with the pulp tissue and causes a photo-biomodulating effect, increasing the cellular meta-bolic activity of the odontoblasts and obliteratingthe dentinal tubules by means of tertiary dentineproduction (Ladalardo et al. 2004; Walsh 1997).

Tengrungsun et al. (2008) compared the effi-ciency of a GaAlAs laser (790 nm, 30 mW, 1 min)with a dentine bonding agent (Scotchbond, 3MESPE) and found a statistically significant reduc-tion immediately and 15 days after treatment inboth of the two groups. No additional reduction inthe level of hypersensitivity 30 days after treatmentwas observed. The dentine bonding agent was sig-nificantly superior to the GaAlAs laser within allmeasuring periods, thus confirming the assump-tion that laser light may act in a different way fromoccluding dentinal tubules (Tengrungsun et al.2008).

The immediate laser effect is assumed to be trig-gered by placebo effects as a result of endorphin re-lease induced by the activation of the pain inhibi-tion system of the organism. This leads to the re-lease of endorphins by the central nervous system,possibly controlling the painful stimulus at the pe-riphery, and causing biostimulative effects thathappen gradually within a few days (Tuner et al.2002; Kimura et al. 2000b; Trowgridge et al. 1990).Another assumption is the blocking of the depolar-isation of C-fibre afferences (Wakabayashi et al.1993). The exact mechanism of action of low-in-tensity lasers in dentine hypersensitivity is notthoroughly understood (Orhan et al. 2010).

_Infra-red wavelengths and high-power density

Laser diodes, some of which have already beentested in vitro and in vivo, with wavelengths in theinfra-red area and a high-power density are easilyavailable on the market. Because of the laser–tissueinteraction of this laser type with high energy per

surface density, its results are comparable to that ofan Nd:YAG laser. The sealing ability of this laser typewas observed with the parameters 810 nm, 2 W and30 ms, and was found to be less than that of CO2,Er,Cr:YSGG lasers and Nd:YAG lasers (Gholami et al.2011).

Clinical findings with the use of a GaAlAs laserof a wavelength of 810 nm at 1.5 to 2.5 mW for oneminute resulted in a rapid reduction of discomfort,15 minutes and 30 minutes after laser irradiation(37 % after 15 minutes and 41 % after 30 minutes)compared with placebo laser application with a re-duction of 9 %. The improvement remained stableuntil two weeks (72 %) and two months (66 %) af-ter application compared with placebo laser appli-cation (a 28 % reduction at two weeks and 26 % attwo months) and the application of 10 % potas-sium nitrate gel (a 36 % reduction at two weeksand 30 % at two months; Sicilia et al. 2009).

_Different effects in different age groups

Ladalardo et al. (2004) evaluated the clinical de-sensitising effect of red and infra-red GaAlAs laserlight application (660 nm and 830 nm, 4 J/cm2, cw,114 seconds, contact mode) in adult patients ofdifferent age groups (25–35 years and 36–45years) as an immediate (15 minutes and 30 min-utes after application; four sessions with intervalsof seven days between each session) and late ther-apeutic effect (15, 30 and 60 days after the con-clusion of treatment). Significant desensitisinglevels were only found in patients aged between 25to 35 with the 660 nm red laser, which was foundto be more effective than the 830 nm infra-redlaser immediately after and in the follow-up peri-ods at 15, 30 and 60 days after the conclusion oftreatment.

In the group of 36- to 45-year-old patients, theeffect of the red laser was only moderate, with re-currence of sensitivity, and the infra-red laser wasineffective. The authors concluded that the desen-sitising effects immediately after laser irradiationresulted from a suppression of evoked potential ofthe pulp nociceptive nerve fibres, with a better tis-sue response in the younger group. Pathologicalprocesses, regressive or atrophic alterations of theodontoblasts and the dentine pulp complex maylower the reaction potential in older patients, withreduced effectiveness of the laser biostimulation(Ladalardo et al. 2004).

A significant clinical improvement was also ob-served after the combined application of GaAlAslaser (808 nm, cw, contact mode, 25 seconds) and

desensitiser toothpaste compared with the tooth-paste alone (Dilsiz et al. 2010a).

_GaAlAs laser and acid resistance

Recently, the GaAlAs diode laser was tested toestablish enhancement of the acid resistance ofdentine surfaces as a preventive method for hyper-sensitivity. A degree of improvement in the acid re-sistance of dentine specimens after laser irradia-tion (808 mn, cw, 60 J/cm2) and erosive challenge (1M hypochlorous acid for five minutes) was foundwithout creating thermal or structural damage(De-Melo et al. 2010). However, the exact mecha-nism of action remains unclear. Laser treatment canbe a useful tool for rapid reduction in pain, and pos-sibly in the improvement of acid resistance of den-tine. Nevertheless, more basic research and long-term clinical trials are needed to evaluate the long-term efficiency of this method and to explain theexact mechanism of action.

_Low-level lasers: He-Ne laser

The He-Ne laser has a wavelength of 633 nm(Moritz et al. 2006) and is a low-level laser. The firstapplication of the He-Ne laser in the therapy ofdentine hypersensitivity was described by Senda etal. (1985), who used an output power of 6 mW andchose two different modes (cw and pulsed, 5 Hz).Effectiveness ranged from 5 to 100 %. In anotherstudy, an effectiveness of 5 to 18 % was achieved(Wilder-Smith 1988). To date, the mechanism of ac-tion of the He-Ne laser has not been explained com-pletely (Moritz et al. 2006). An energy level of 6 mWdoes not alter the enamel or dentinal surface struc-ture morphologically; however, laser energy trans-mits through enamel and dentine and reaches thepulp tissue (Watanabe 1993). Physiological experi-ments have shown that the He-Ne laser applicationdoes not influence nociceptors of circumferentialA-�- or C-fibres (Jarvis et al. 1990), but it does in-fluence electrical activity (action potential), whichin healthy nerves is enhanced by about 33 % afterapplication (Rochkind et al. 1986). The effect islong-lasting and leads to an increase in the actionpotential of nerve fibres for more than eightmonths after laser application (Rochkind et al.1986).

_He-Ne laser compared to Nd:YAG laser

In a clinical study (Gelsky et al. 1992), which wasaimed at testing the effectiveness and confidenceof the Nd:YAG laser in the therapy of dentine hy-persensitivity in vivo (see below), the He-Ne laserwas applied to one group and the He-Ne laser andthe Nd:YAG laser were applied to the other group

(30–100 mJ, 10 pps increments of ten to 40 seconds,total application time < two minutes, without localanaesthesia). Dentine hypersensitivity was meas-ured mechanically (dental probe) and thermally(stream of cold air) with the aid of a VAS. Addition-ally, the pulpal sensibility was evoked electrically.Initially and after three months, X-rays were takento identify possible side-effects of the laser appli-cation. Directly after laser application and threemonths later, a reduction in the level of discomfortwas observed. After three months, dentine hyper-sensitivity evoked by thermal stimuli was scaledback to 63 % and hypersensitivity evoked by me-chanical stimulation was scaled back to 61 %. Com-pared with the combined application of He-Ne andNd:YAG lasers, there was not much difference (re-duction of dentine hypersensitivity evoked by ther-mal stimulation to 58 %; evoked by mechanicalstimulation to 61 %). All of the teeth were vital af-ter application and no side-effects or complica-tions could be detected.

If dentine hypersensitivity is conditioned by thehydrodynamic mechanism exclusively, (thermal)effects of Nd:YAG laser application should reducedentine hypersensitivity primarily (Gelsky et al.1992). In contrast, He-Ne laser application shouldnot lead to important effects. Thus, it is assumedthat a surficial modification is not the only desen-sitising factor, but that there is apparently also aneurophysiological component (Gelsky et al. 1992),which is affected by biostimulative effects.

In a study with a similar design, the reduction ofdentine hypersensitivity after He-Ne laser applica-tion alone, as well as after combined He-Ne laserand Nd:YAG laser application, was detected. It re-mained stable for six weeks (Halket et al. 1996)._

Editorial note: To be continued in our next issue of Laser. A list of references is available from the publisher.

overview I

I 25laser1_2012

Dr Ute Botzenhart Department of Orthodontics Centre of Dentistry and Oral Health Ernst Moritz Arndt University of GreifswaldGermany

Dr Andreas Braun/Prof Matthias FrentzenDepartment of Periodontology, Operative and Pre-ventive Dentistry University of BonnGermany

_contact laser

I case report

Fig. 1_Initial photograph.

Fig. 2_Immediately after surgery.

_Introduction

Pyogenic granuloma (PG) is a benign non-neo-plastic mucocutaneous lesion. It is a reactional re-sponse to constant minor trauma and can be relatedto hormonal changes. In the mouth, PG is manifestedas a sessile or pedunculated, resilient, erythematous,exophytic papule or nodule with a smooth or lobu-lated surface that bleeds easily.1, 2, 3 The size of PGvaries from 2 mm to 2 cm in diameter. Occasionally,the lesions may reach a diameter of up to 5 cm.7, 9 PGpreferentially affects the gingiva, but may also occuron the lips, tongue, oral mucosa and palate.

The appearance of PG usually ranges in colourfrom red/pink to purple. Younger lesions are morelikely to be red because of the high number of bloodvessels. Older lesions become pink.5, 6 The exact causeof PG is unknown; trauma is usually a precipitatingfactor.

Several methods can be applied to remove PG, likesurgery, electrocauterisation and laser treatment. Theargon laser has long been used to treat PG, but it isclaimed to result in an increased risk of scarring. Thereare several reports about treatment with the pulseddye laser, although it has only been successfully em-ployed in removing very small granuloma. In the pastfew years, the continuous-wave carbon dioxide laserhas proved to be an effective treatment option.2, 3 Inthis study, I report on a new experience in the treat-ment of PG with the 980 nm diode laser.

_Patients and method

Two patients with PG were examined in this study.They were treated with the 980 nm diode laser at theUniversity of Tirana’s Dental School in Albania. An ini-tial clinical examination consisting of the medical anddental history and a thorough extra- and intra-oralexamination was performed. A complementary blood

The management of pyogenic granuloma withthe 980 nm diode laserA case report

Author_Dr Merita Bardhoshi, Albania

26 I laser1_2012

Fig. 1 Fig. 2

case report I

test, complete blood count, and erythrocyte sedimen-tation rate test made it possible to exclude infectiousdiseases. The patients had no systemic complaints.The data collected was evaluated and a clinical diag-nosis for the type of lesion was established (Fig. 1). In-cisional biopsies were taken pre- and post-opera-tively, and the specimens were histologically exam-ined (Fig. 2). Patients were given written and verbal in-formation on the nature of laser treatment and thesigned informed consent forms were obtained priorto the treatment. The 980 nm diode laser was appliedusing the following parameters: continuous wave,300 µm optical fibre and 6 W power. The treatmentwas conducted under infiltration anaesthesia (2 % li-docaine, 1 cc). The treatment area was cooled by theapplication of ice for two to five minutes post-oper-atively. All wounds were left open to heal by granula-tion and secondary epithelisation; therefore, no su-tures were required (Fig. 3). After the treatment, anal-gesic medication was prescribed to be taken as re-quired, but no antibiotics were prescribed. Thefollow-up visits were scheduled at ten days, onemonth, six months, and one year after surgery. All ofthe lesions were photographically documented at allstages of treatment and healing.

_Results

Post-operatively, there was no bleeding or pain.The power setting of 6 W in continuous wave modeand focused contact handpiece appeared to lead tosome superficial tissue necrosis associated with de-layed wound healing. The wounds were completelyhealed after four to five weeks without scar formationor pigmentary changes. The cosmetic effect of thelaser therapy was evident (Fig. 4). No recurrence wasobserved in the patients who were followed up oneyear after the surgery.

_Discussion

Aesthetic Treatment of PG consists of the removalof the lesion. Current treatment modalities include

chemical cauterisation and surgical excision. How-ever, these methods do not exclude the risk of com-plications, such as scarring or pigmentary changes.These complications may lead to aesthetic problemsfor patients, who accept the surgical removal of PGonly with great difficulty. The conventional lip-shaveprocedure is often painful, results in significantbleeding and poses cosmetic concerns. Laser treat-ment of the lips does not compromise the importanceof the lip, its discrete anatomic borders such as thevermilion border, or its functional functionality.

Various laser devices have been successfully usedto treat PG, including the 585 and 595 nm pulsed dyelaser, the 1,064 nm Nd:YAG and the dioxide carbonlaser. The pulsed dye laser is safe, but it can only beused for small PG lesions. The carbon-dioxide laserhas proved to be an effective treatment option. Its usepermits rapid, minimally invasive surgical treatment,but the non-specific coagulation it results in may leadto scarring.

Treatment with the 980 nm diode laser is a viabletreatment option. The 980 nm diode laser beam is wellabsorbed by haemoglobin. The excision was well per-formed and suturing after surgery was not necessarybecause of the good coagulation. The surgical periodwas significantly reduced. From the good results ob-tained, it was concluded that the application of the980 nm diode laser in the treatment of PG appears tobe of beneficial effect._

Editorial note: A complete list of references is availablefrom the publisher.

Fig. 3_Pre-op Specimen.

Fig. 4_One year after the

post-treatment.

I 27laser1_2012

Dr Merita BardhoshiOral SurgeonDental School, University of Tirana, Albania

meritabardhoshi@yahoo.com

_contact laser

Fig. 3 Fig. 4

I industry report

_Introduction

Tooth whitening has a long, historical tradition thatextends back to the very first centuries AD. Along withtooth extractions, it was an accepted practice already inmedieval times, performed by applying aqua fortis (a so-lution of nitric acid) after a simple rough polishing of theenamel surface. The procedure was performed by the“dental surgeons” on duty in those days, known as bar-bers.

In the 19th century, new methods were developedwith oxalic acid (Chappel 1887) and super-peroxide,which is thus the first documented use of hydrogen per-oxide (H2O2; Harlan 1884). In 1918, Abbot discovered afundamental formula for tooth bleaching, entailing acombination of light, heat production and the chemicalinteractions of stabilised H2O2at 35 % (superoxol). Sincethen, the formula has been refined continuously, but notchanged in essence.

Studies in the late sixties by Zach and Cohen, and Ny-borg and Brännstorm determined the safety settings tocontrol heat influence on the pulp, and in 1970 the ef-fectiveness of H2O2 on dentine was established. Duringthe sixties and seventies, carbamide peroxide was used

as an oral antiseptic, with an additional whitening ef-fect discovered during treatment. This phenomenonwas subsequently analysed (Klusmier 1960), and Hay-wood and Heymann later developed the original home-bleaching process. The first commercial products werelaunched on the market as White & Brite by Omni (1989)and Opalescence by Dent Mat (1991), among many oth-ers.

The current home-bleaching process entails thechemical decomposition of carbamide peroxide intoH2O2, among others, but with an effect that is six timesweaker in comparison to the original protocol. In the latesixties, Nutting and Poe developed the walking bleachmethod for non-vital teeth, which involved placing amixture of superoxol and sodium perborate into thepulp chamber for a week, a protocol that was furtheradapted without altering the basics.

An entirely new series of heat sources like plasmaand LED lamps, combined with corresponding bleach-ing gels, paved the way to the new millennium withnames like BriteSmile (Discus Dental) and the variousgenerations of Zoom.

Professional literature on bleaching and cosmeticsemerged at the beginning of the nineties, with the firstpublications by the pioneers Goldstein and Garber, fol-lowed by many others.

_Thermocatalytic or photocatalytic?

The two principles are not mutually exclusive. Thebleaching procedure was described step by step in 1991in Albers’ ADEPT report. It involves a redox process inwhich complex, dark-pigmented carbon rings are re-duced through oxidation to more simple chains that ab-

Bleaching: New approachesto a traditional minimally invasive therapyCosmEt(h)ics vs. aesthEt(h)ics

Authors_Dr Kresimir Simunovic & Monica Tuzza, Switzerland

28 I laser1_2012

...the pursuit of truth and beauty is a sphere of activityin which we are permitted toremain children all our lives.

Albert Einstein

I industry report

30 I laser1_2012

sorb less light, reflecting light more intensively and ap-pearing brighter. The redox process continues until thesaturation point is reached. Thus, it functions as an ab-solute emergency stop to avoid any fatal decompositionof the tooth structure to CO2 and H2O through rupturesof the molecular structures, which would result in nox-ious complete oxidation.

_Laser-assisted or laser-activated?

Since November 2009, dental practitioners have hadthe choice of a new innovative laser-activated whiten-ing method, initiated by a wavelength-specific chro-mophore or activator as an essential part of the bleach-ing powder. Additional TiO2 limits the thermal side-ef-fects, allowing a maximal increase of 1.5 to 2°C at thedelicate border between the bleaching gel and theenamel surface.

A corresponding large series of ESEM analyses fromthe University of Vienna (Prof Andreas Moritz and ProfJohann Wernisch) provided no evidence of any changein the enamel-surface morphology before and immedi-ately after bleaching. Consequently, there is no longerany need for specific 48-hour post-operative instruc-tions about smoking or food and drink consumption, a

conclusion supported by several basic studies. There isno risk either of any kind of pigment staining the teethduring the first two days.

From our clinical experience, we have concluded thatpost-operative complaints or sensitivities are very rareand limited to the day of treatment. In addition, thewhitening process continues for about two more dayspost-operatively and the final result is often a natural-looking aesthetic whitening of several shades. This pro-tocol even improves grey tones: a revolutionary out-come, since those shades are very challenging for anyexternal whitening process.

The protocol of this new method of laser-activatedtooth whitening includes protective glasses and ableaching set, with a wavelength-dependent activatorin the bleaching powder and H2O2 liquid (about 25 %).They are mixed to a creamy consistency and then left torest for two minutes. Pumice (no prophy paste) is usedto remove biofilm from the teeth, and the gingiva is cov-ered by the liquid dental dam (Figs. 1–3). After the den-tal dam set, the mixture is applied to the buccal toothsurfaces (Fig. 4) and then irradiated at the chosen wave-length, scanning each surface for 30 seconds. Three orfour cycles per session are allowed and a final applica-

Fig. 1 Fig. 2 Fig. 3

Fig. 4 Fig. 5 Fig. 6

Fig. 7 Fig. 8 Fig. 9

industry report I

I 31laser1_2012

tion can be done after two weeks at the earliest. A finalpolish and fluoride application concluded the bleachingsession (Figs. 5 & 6). The patient is then given basic in-structions for post-operative care. A shade comparisonshould be done after a minimum of two days .

_Laser-activated whitening: Three cases from our office

Case 1The first case was a cosmetic pre-treatment before

veneer placement. A detailed spectrometric analysis(SpectraShade by MS.ch as a clinical application, simu-lated on Fig. 7) before (Fig. 8), immediately post-op (Fig. 9), and not earlier than two days on six tooth sur-faces accompanied the whitening process. The resultswere registered and validated by using the originalSpectra Shade software. For this purpose, the results ofthe complete analysis before the first bleaching cycleand the graphical translation of the shade variationswere compared to the classical VITA parameters (redframe, Fig. 10). The dark blue frame shows the evidentshift to brighter shades (Fig. 11) just before and imme-diately after the complete bleaching on the day of treat-ment. Another spectrometric analysis was carried outeleven days after the operation (Fig. 12).

Bleaching (Fig. 13) was followed by surface condi-tioning with Er:YAG/Fidelis Plus III by Fotona and ce-mentation with Variolink Veneer and Syntac Classic byIvoclar Vivadent. Minimally invasive veneering (Fig. 14)completed the treatment.

Case 2The second case demonstrates a retreatment of an

earlier different bleaching with an already high shadeas a challenging starting point. The protocol of thiscase entailed laser irradiation of three cycles of 30 sec-onds each using an Nd:YAG laser (Fidelis Plus III, Fo-tona) with the corresponding R24 bleaching hand-piece. A complete analysis was made before the firstbleaching, with a translation of the shade variations tothe VITA parameters. In addition, a spectrometricanalysis was carried out immediately after the threebleaching cycles by Nd:YAG/Fidelis plus III (Fotona)with the bleaching hand piece R24 and the correspon-ding shade variations (Fig. 15). One week later, anotherspectrometric analysis followed (Fig. 16: numericaltranslation of the shade variations (Fig. 17: final re-sult). Fig. 18 gives a comparison between the initial pa-rameters before the bleaching (red frame), immedi-ately after the bleaching (blue frame) and the final re-sults (darker blue frame).

Fig. 14 Fig. 15

Fig. 11Fig. 10

Fig. 17 Fig. 18Fig. 16

Fig. 12

Fig. 13

I industry report

32 I laser1_2012

Case 3The third case was treated using combined two-step

whitening before the definitive aesthetic restoration.The first step entailed combined laser-assisted en-dodontic revision of the non-vital left maxillary centralincisor using Er:YAG and Nd:YAG lasers (Fidelis Plus III,Fotona), followed by selective external bleaching usingan Nd:YAG laser with the R24 hand piece for four cyclesof 60 seconds each (Figs. 19 & 20). In addition, Figs. 21 &22 show the final results of the spectrometric analysisof the central left incisor (after selective external bleach-ing of this surface only). The second step involved com-plete combined bleaching of both arches using an 810 nm diode laser (ARC) with a photo-biomodulation(PBM) hand piece for two cycles of 30 seconds each andan Nd:YAG laser with the R24 hand piece (Fotona) forone cycle of 30 seconds (Figs. 23–24). Figs. 25 & 26 of-fer a comparison between the situation before anytreatment and after the final bleaching (before defini-tive restorations).

_Conclusion

This new and innovative addition to the field of laser-assisted tooth whitening is a precious enrichment tominimally invasive therapies that are part of the daily

office routine. Tooth bleaching is a prudent evidence-based choice in cases of aesthetic imbalance, often be-cause tooth-shade variation is an evident social, privateand professional obstacle, and the clinician’s profes-sional knowledge and the patient’s treatment needs arethe focus. For the laser user, tooth bleaching is a safe andcost-saving alternative because the bleaching powdercan be adapted to the in-office laser wavelength(s) viaspecific activators. Handling is easy and can be carriedout by assistants as part of a low-level energy lasertreatment._

Fig. 20

Fig. 23 Fig. 24

Dr Kresimir Simunovic and Monica TuzzaOffice for Laser-Assisted DentistrySeefeldstr. 1288008 ZurichSwitzerland

ksimunovic@smile.chwww.simident.ch

_contact laser

Fig. 25 Fig. 26

Total: Tooth: C1: Diff.:L: 71.60 71.50 0.10C: 15.73 14.27 1.46h: 80.79 87.36 -1.72

E: 2.26

Neck: Tooth: C1: Diff.:L: 73.05 71.10 1.95C: 17.22 16.24 0.98h: 77.05 80.78 -1.09

E: 2.44

Fig. 22

Total: Tooth: C2: Diff.:L: 68.70 68.53 0.18C: 19.14 19.01 0.13h: 81.90 86.23 -1.44

E: 1.46

Neck: Tooth: A3: Diff.:L: 70.89 71.21 -0.32C: 22.00 22.72 -0.72h: 79.08 79.14 -0.02

E: 0.79

Fig. 21Fig. 19

AEEDC_2012_A4.pdf 1AEEDC_2012_A4.pdf 1 05.03.12 14:0905.03.12 14:09

I industry report

Fig. 1_Generalised horizontal and

vertical premature bone resorption in

a 37-year-old patient.

Fig. 2_Probing and pocket depth

measurement.

_Introduction

In systematic periodontal therapy, furcationtreatment is still quite a challenge for the dentist.Because of the difficulties in the handling of thisspecial treatment area, various therapy approacheshave been discussed over the past few years. For in-stance, the combined use of laser and gradually re-leased chlorhexidine xanthan gel supports the re-mission of inflammation considerably.

Periodontal disease has become an endemic dis-ease in countries with a Western way of life. Over50 % of adults in Germany between 35 and 45 yearsof age suffer from moderately severe periodontitis.Today, periodontal disease poses the highest threatto general dental health and is responsible for pre-mature loss of teeth in affected patients (Renggli2010), which certainly implicates a substantial lossof quality of life.

In the afore-mentioned age group, the peri-odontal bone resorption usually extends to morethan one-third of the total root length and spreadsevenly horizontally. Therefore, an orthopantomo-gram or X-ray can be used for initial diagnosis. Adetailed patient anamnesis and a correspondingpatient-oriented prevention and therapy plan areessential prior to periodontal treatment. Periodon-tal treatment represents a wide field in daily den-tistry, and can only be completed successfully if thedentist, the patient and the dental assistants co-operate.

_The role of oral micro-organisms

In the multifactorial aetiopathogenesis of peri-odontopathies, a decisive role is attributed to oralmicro-organisms. The oral flora features a naturalbalance between various micro-organisms, andeach patient has an individual oral flora. Therefore,

Effective treatment of periodontalproblem areasCombined therapy

Authors_Prof Frank Liebaug & Dr Ning Wu, Germany & China

34 I laser1_2012

Fig. 1 Fig. 2

industry report I

I 35laser1_2012

Fig. 3_Scaling and root planing.

Fig. 4_Flexible laser fibre in the

pocket area, ensuring diffuse disper-

sion of laser light in the surrounding

tissue.

the existence of periodontal pathogenic micro-or-ganisms alone is not likely to