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Faculty Guidelines for Department Policies and Protocols

1. Faculty Evaluation, Attendance, Professionalism and Time Off

This outlines our policies and criteria for faculty evaluation in the Division of

Prosthodontics. These policies and criteria are directly related to how merit increases

are allocated; recommendations for promotion are made, and may also be linked to

other opportunities to enhance your academic career.

Teaching Responsibilities:

1) Tufts University School of Dental Medicine (TUSDM) Vacation Policy:

a. Full-time faculty have 20 days of vacation per academic year; you are

advised to submit your vacation request at least 3 weeks in advance

b. Part-time faculty have 10 days of vacation per academic year; you are

advised to submit your vacation request at least 3 weeks in advance

2) Meetings or Continuing Education (CE) Courses:

a. Full-time faculty have two days per academic year to attend meetings or

CE courses.

b. Part-time faculty have one day per academic year to attend meetings or

CE courses.

c. If you are a presenter at a meeting or course, you may be granted additional

days depending upon clinic coverage and final approval from me.

d. If your meetings or CE days exceed the allotment mentioned above,

vacation days will be charged.

3) Sick Days:

a. If you are sick more than three days, university rules require submission of a

physician’s note, otherwise vacation days will be charged.

b. If you or an immediate family member is sick and you need to take time off,

university rules require you to be placed on the Family Medical Leave Act

(FMLA). If this occurs, please contact me immediately.

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4) Other:

a. A non-DMD faculty member who is taking the National Boards I/II or the

Northeastern Examination Regional Board (NERB) Licensing Examination

must submit proof of participation in the examination(s).

Professionalism:

You are required to maintain professionalism among your peers, students and staff and

be a role model for students.

Certain behaviors are unacceptable in our school. They are:

o rudeness to students, peers, or staff

o not being responsible for student learning and patient care by “pushing it off”

onto someone else or always referring problems to another faculty member

for action

o always on the phone (office or cell) during clinic sessions

o arriving for clinic sessions late and/or leaving early especially when students

have not completed procedures

o leaving the clinic mid-session without informing your floor mentor,

prosthodontics partner, and Practice Coordinator (PC)

o exhibiting defensiveness when informed you are late or chronically tardy,

o drinking or eating during the clinic session

You will be informed by your floor mentor and/or me if behaviors such as the above

occur, and they will be documented and filed in your permanent record.

Attendance:

Policy Regarding Multiple Absence Requests for the Same Dates and Sessions

There are several occasions when many faculty members submit absence requests for

the same dates and sessions (e.g., before and after holidays and school breaks, the

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end of the academic year, major professional meetings such as ACP, AP, GNYAP, AO,

or YDC).

The following policy is established to maintain a minimum of three faculty members per

clinic floor:

o Submit your absence request form (ARF) to Dr. Nui’s mailbox in the

department office (DHS-2) at least three weeks in advance.

o You will be approved by ARFs requesting the same dates and sessions on a

first-come, first-served basis.

o If your ARF is not approved it is your responsibility to find another faculty

member to replace you, otherwise you are expected to attend your assigned

clinic session(s).

Policy Regarding Emergency Absences

o Call the department office at 617-636-6585 or E-mail

TUSDM_PROS@tufts.edu as soon as you realize that you will be late for or

unable to attend your clinic session(s).

o When reporting an absence, it is only necessary to state which session(s) you

will be absent from and the specific absence type (sick or vacation) that

should be applied to the absence.

o When reporting a late arrival, provide an estimated time of arrival (ETA) and

your assigned group(s).

Evaluation:

You will be assessed by all data recorded during the academic year for fair allocation of

merit raises. For instance, if your sick days are very high compared to the rest of the

faculty, and/or you exceed your allotted vacation time, it may negatively impact your

merit increase. Praise by students, peers and staff is also documented and will be

considered in your evaluation.

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2. Clinical Procedures in Undergraduate Prosthodontics

Please read this important message regarding prosthodontic treatment plans and

adhere strictly to the following protocol:

Because of recent patient care problems resulting from improper or inadequate

treatment plans, effective immediately, all new treatment plans for prosthodontics

should have a co-signature from one of the Team Leader or QA faculty or Dr.

Chaimattayompol (Nui), Suzuki, Muftu, or D Park. These faculty members have

administrative sessions and are responsible to review mounted diagnostic casts, wax-

ups, and templates before the student make an appointment to see his/ her patient.

Without the properly co-signed step sheet, Practice Coordinator (PC) will not enter

the treatment plan in Axium; therefore, the student will not be able to make the

appointment to treat the patient until this is complete.

Students are advised to use the appropriate step sheet as a guide for clinical care and

laboratory procedures and review textbooks and lectures before providing patient care.

All step sheets are available on the bookshelves in the 2nd floor reception area. There

are 5 types of prosthodontic step sheets: (1) Fixed & Removable Partial Denture, (2)

Complete Dentures (Interim Immediate/Conventional Immediate/Conventional/Over

denture), (3) Interim Partial Denture, (4) Implant and (5) Denture Repair step sheet.

Please review the following prosthodontic procedural rules for patient care and use the

appropriate step sheet. Any exceptions will require signature from one of the following

faculty members: Drs. Weber, Chaimattayompol (Nui), Suzuki, Muftu, D Park, Tsakalelli

or Lamberti

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GUIDELINES FOR PROSTHODONTIC TREATMENT IN PREDOCTORAL PROGRAM

I. “NO CHANGE IN VERTICAL DIMENSION OF OCCLUSION” (with the exception of

combination of removable prostheses i.e. CD/CD or CD/RPD or RPD/CD)

II. PROSTHODONTIC TREATMENT FOR DENTATE PATIENTS

A. FIXED PROSTHODONTICS:

1) YR-3/4 students should diagnose, manage, treatment plan, and treat the dentate

patient with defective teeth who present with the following conditions or

treatment requirements:

a) A PDI Class I or II

b) Maximum of 5 single crowns/ patient

III. PROSTHODONTIC TREATMENT FOR PARTIALLY EDENTULOUS PATIENTS

1) YR-3/4 students should diagnose, manage, treatment plan, and treat the

patients who present with the following conditions or treatment requirements:

A. FIXED PROSTHODONTICS

1. Simple fixed partial dentures (FPD's) as defined by Fundamentals of Fixed

Prosthodontics, 3`d Edition, Shillingburg et al. Quintessence Publishing Co.

Inc. Chicago IL, 1997, pp106-113 (Maximum of 2-FPDs/ patient ;

Maximum of 5 units/FPD ; Maximum of 6 units/patient ; Maximum of

2-quardrant/patient)

B. IMPLANT PROSTHODONTICS

1. Single-unit crowns: a maximum of three implants in an arch (4 total implants

per patient)

2. Implant supported FPD : a maximum of 3-unit interconnected implant

restorations (4 total implants per patient)

3. Implant assisted RPD; a maximum of 2 independent implant with independent

attachment

C. REMOVABLE PROSTHODONTICS

1. A Partially Dentate PDI Class I or II or III with permission

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2. Conventional cast metal removable partial dentures

3. Immediate interim acrylic resin removable partial dentures

4. Prosthesis relines and repairs

IV. PROSTHODONTIC TREATMENT FOR EDENTULOUS PATIENTS

1) YR-3/4 students should diagnose, manage, treatment plan, and treat the

patients who present with the following conditions or treatment requirements:

A. REMOVABLE PROSTHODONTICS

1. An Edentulous PDI Class I or II or III with permission

2. Conventional complete dentures

3. Interim and/or Conventional immediate dentures

4. Complete denture relines/repair

B. IMPLANT PROSTHODONTICS

1. Mandibular-2-implant-retained and tissue-supported overdenture (must be

lone-standing non-splinted abutments)

Any treatment plan that does not conform to the above mentioned guidelines shall be referred to

Postgraduate Clinic (PG Prosth, PG Implant, PG Esthetics or GPR Programs).

Before any definitive prosthodontic treatment is begun:

1) All patients must have a written sequenced treatment plan. First, a draft

should be completed in the case notes and then transferred onto the step

sheets.

If more than three units of fixed prosthodontics, RPD, complete dentures, or implant

prosthodontics are planned (even if the patient may not want to have all of the

prosthodontics completed this time), the treatment plan must be reviewed by one of the

following faculty members: Drs. : Drs. Weber, Chaimattayompol (Nui), Suzuki, Muftu, D

Park, Tsakalelli or Lamberti

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2) The step sheet must be signed by a full-time Prosthodontics faculty member

before the treatment plan is sequenced. The following must be completed

before reviewing with the faculty member:

An informed consent must at least be discussed and preferably signed.

No more than two units of fixed prosthodontics or a three unit bridge

should be done in any one quadrant at a time. This includes NOT doing

opposing crowns. If there is a reason to alter the plane of occlusion, then

the crown or bridge in the quadrant that is to be altered should be

completed first. A wax-up of the appropriate opposing occlusion can be

made to send out to the laboratory for the change-of-occlusal-plane

prosthesis to occlude with.

Before any definitive endodontic treatment is begun, a complete (fixed or

partial denture) prosthodontic treatment plan must be completed with

mounted study casts and a diagnostic wax-up. Emergency endodontic

treatment should be to open and clean the canal or drain ONLY. No root

fill should be completed before a treatment plan for the prosthodontics is

finalized.

If an RPD is in the treatment plan or is possible in the future, the partial

denture design must be completed and reviewed. Crowns that are to be

abutments for RPD must be treatment planned and the RPD design

approved. Use the step sheet for fixed partial denture and RPD

combination cases.

All prosthodontic cases must have study casts mounted on articulator,

diagnostic wax-ups completed and/or RPD treatment plans and designs

completed before any crown preparations are started. No crowns will be

sent out to the laboratory until all of the preparatory diagnostic and

treatment planning procedures are completed.

All proposed implant treatments must be reviewed by one of the following

faculty members: Drs. : Drs. Weber, Chaimattayompol (Nui), Suzuki,

Muftu, D Park, Tsakalelli or Lamberti before the treatment plan is decided

upon. Any potential implant cases should be seen by a Prosthodontic

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faculty member with mounted study casts before any surgical consultation

with Periodontics or Oral Surgery Departments.

Students are advised to work consistently with the same faculty member.

If they are unable to do so, they should consult with the primary faculty

member to suggest another faculty member. The two faculty members

should discuss the treatment plan.

Clinical Treatment:

All bridges must have temporary restorations made with pontics (not

individual temporary crowns on the abutment teeth only). This is done so

that the abutment teeth do not move when the castings are made and the

porcelain is being applied to the frameworks.

Prefabricated posts (i.e., Parapost) are now considered to be the default

post procedure. The core material is generally composite or amalgam.

If a crown or bridge abutment does not fit in the mouth but does fit the die,

a new impression must be made in order to redo the prosthesis. Refer to

‘Redo Criteria’.

It is strongly advised that the student have the instructor’s signature for

each step on the step sheet. Students are not allowed to start preparation

and temporization for FPD without instructor’s signatures for the

Prosthodontic Tx plan and Dx wax-up & template on the step sheet.

This policy also applies to the other Prosthodontic procedures.

All prosthodontic cases will not be sent out to a dental lab or be delivered

without the step sheet properly signed for each step by faculty member.

Remember:

Mounted study casts are required for all fixed and removable prosthodontics. The

procedures listed below must be approved by one of the following faculty members:

Drs. Weber, Chaimattayompol (Nui), Suzuki, Muftu, D Park, Tsakalelli or Lamberti

\

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More than three units of fixed prosthodontics in any one quadrant or six or

more units of fixed prosthodontics overall

Implant prosthodontics

Surveyed crowns for RPD

3. Core Procedures for Fixed Prosthodontics and Implant Dentistry

1) Fixed Prosthodontics

Finish line design: The most preferred finish line is deep chamfer or shoulder on the

facial/buccal and chamfer or shoulder with bevel on the lingual/palatal. However, all

other finish line designs are also acceptable according to the clinical situation. Faculty

members are strongly advised to discuss and explain very well with the choice of finish

line selection to the students to lessen the confusion. Bevel is not recommended or

anterior tooth preparations.

Structurally damaged dentition: When the structurally damaged dentition is served to

be an abutment for the retainer for either fixed or removable partial denture, please

adhere to the following protocol:

For single unit crown abutment for FPD - after proper inform/consent to the

patient with the definitive treatment plan, prepare the questionable tooth for the

anticipated retainer design i.e. partial coverage or complete coverage

restoration

Evaluate the amount of the coronal tooth structure and determine the potential

outcome of the anticipated prosthesis according to the resistance and

retention forms. The interim fixed restoration may be utilized to test the

resistance and retention forms.

The designated Prosthodontic faculty members may prescribe elective

endodontic treatment in order to restore the structurally damaged dentition

with dowel/core.

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Post & cores:

Used for single rooted teeth (Cast Post & Core).

1. Clean the canal of gutta percha and sealant with Gates Glidden burs, but leave

at least 4.0 mm of seal at the apex of the tooth.

2. Prepare the tooth as if it were to be a final crown preparation.

3. After the crown preparation is completed, remove any thin tooth structure

between the internal post preparation and external crown preparation so

approximately 1.0 mm thickness of tooth structure remains between crown

preparation and canal preparation. Retaining maximal height and thickness of

tooth structure above the cervical line is important so function stress will be

placed on tooth rather than post.

4. Smooth walls of canal so no undercuts remain using the same Gates Glidden

burs. For deep undercuts it may be better to block them out before smoothing the

walls. Any material may be used as a block-out, but one of the chemical set

cements work best. Please seek faculty assistant when you need block-out

procedure.

a. On occasion Peeso reamers may also be needed to assure there are no

undercuts in the canal. If this is deemed necessary, a faculty signature will

be required to get them from the dispensary. Peeso reamers cut very fast,

and it is possible to perforate the canal(s) when using them. They should

be rotated in the canal USING FINGERS ONLY. A PEESO REAMER IN

A HANDPIECE SHOULD NEVER BE USED.

5. Alcohol will help remove any remaining eugenol that may be left over from the

sealant used for gutta percha. Paper point(s) or a very small bit of cotton lightly

twirled onto the end of a #2 Gates Glidden bur can be dipped into alcohol and the

canal vigorously cleaned before the plastic pattern is made. (As you will

remember, eugenol retards the set of acrylic so the pattern would be rough and

soft and the casting would not fit.)

6. If needed, reduce the top of the preparation between the canal and the outside of

the preparation so that at least 1.0 mm of tooth structure remains. THIS

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SHOULD BE A BUTT JONT. THERE MUST BE NO BEVEL (A bevel is

unnecessary, and will not allow the casting to seat completely into the canal.

Remember that there should be no liner in the investment for a cast post. This is

done so that there would be no expansion of the investment. Expansion would

create a larger post; a larger post would not seat. If a bevel is placed, there

would have to be expansion to allow for seating of the beveled post over the

beveled tooth structure. A bevel is also more likely to have a bubble under it

during investing.)

7. Make the temporary post and crown now, before you proceed to step #8.

8. Using two of the plastic patterns, place GC resin onto their tips and dip this into a

cup of hot water for two or three seconds. This will create a slight skim of setting

acrylic preventing the plastic pattern/acrylic from running all over the place. This

will also result in it being less likely for the pattern to get stuck in the canal. The

canal also should not be dry. It should be wet with saliva so that the saliva can

act as a lubricant.

a. After about 10 seconds, gently pull the setting material part way from the

canal and replace. Do this every 5 to 10 seconds while the acrylic is

setting to “burnish away” any small bumps on the post created on the

pattern from undercuts in the canal.

9. Add acrylic to the top of the pattern on and between the two plastic posts

10. After setting, the pattern can be prepared as if it were tooth structure. The final

pattern should look like a prepared tooth.

11. Remove the prepared pattern and inspect the area of the butt joint. If there is

flash, cut it away with a scalpel. Flash will act the same as a bevel.

12. Cement the temporary with non-eugenol containing temporary cement. Check

the occlusion on the temporary so that there are no high contacts or lateral

excursive contacts.

Send out to the laboratory

Use the Transcend-online prescription process.

The Patterns will not be sent out if:

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there is any softness to the pattern as a result of eugenol contamination

there is a bevel to the pattern and not a butt joint where the pattern meets

remaining tooth structure

there are any noticeable voids

There are any noticeable undercuts

13. When the cast post returns from the laboratory, remove the temporary from the

tooth and immediately place the temporary into the temporary cement remover to

clean away all of the temporary cement. The temporary can be shelled out and

relined on the finally cemented post.

14. Clean all of the temporary cement from the canal with hand instruments and

then, using the same technique as above, clean the canal with alcohol on a

cotton pellet.

15. Gently insert the post into the canal. If it does not go to place easily, inspect

carefully for any small bubbles on the post or flash left on the edge of the pattern.

Use fit checker to see if there are any small areas where the acrylic may have

flexed over undercuts in the canal but where metal will not. DO NOT USE

CHLOROFORM AND ROUGE.

16. Carefully adjust the small area where the fit check has indicated.

17. If more than two areas are shown to be undercut, the canal must be re

instrumented and another pattern made.

18. Once the post is seated, clean the canal with alcohol again to remove any fit

check residue.

19. Mix Rely X Unicem or any self-setting cement and place onto post.

20. Place post gently into canal, remove and reseat immediately to assure that all the

post is covered with the cement. Allow the cement to fully set, and refine the

tooth preparation.

21. Grind out the temporary post from the temporary and reline onto the post

now.

22. If time permits, make a final impression for the crown.

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Used for multiple rooted teeth (Prefabricated Post)

1. Remove the temporary seal from the canal. Clean the canal using the technique

described above for post and cores, but DO NOT PREPARE THE TOOTH FOR A

CROWN AT THIS TIME.

2. Generally, the 3 or 4 Gates Glidden burs will clean the canal sufficiently to allow

placement of the #3 or #4 paraposts. On occasion a #5 Gates Glidden will be

needed in a large palatal canal on a maxillary molar or distal canal on a lower molar

for placement of a #5 post. The parapost drills can be used BUT CAREFULLY, AND

ONLY WITH THE FINGERS, NEVER IN THE HANDPIECE.

3. Fit the parapost into the canal. It should not “wobble”. If it does, it is either not

seated all the way or the canal is too large for the post. Measure the depth of the

canal and post using rubber rings as in endodontics. Adjust the width of the canal or

change the post to one with a smaller or wider diameter.

4. When the post fits, clean the canal before cementing as described above in cast

posts.

5. Cut the top of the post so that at least 3.0 mm of post remains above the top of the

canal to retain the core material. Cement the post using the same technique as in

cast posts above.

6. Cement the posts using the same technique as in cast posts above.

7. Clean the material away from the posts using an explorer when the cementing

material is “rubbery” – about 1 minute.

8. Place a matrix band and fill around the posts and complete the core using amalgam.

You will want to have about 2.0 mm of core material remaining above the posts after

the preparation. It is most important however, to have the core material retained by

the posts. Thus erring on the side of a post that is slightly longer is better than

having a short post and a lot of core material over the too short posts.

Prefabricated (Parapost XP) for single rooted teeth

When more than 1/2 coronal tooth structure remains after crown preparation and

removal of too thin tooth structure and/or undermined tooth structure, the prefabricated

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parapost XP can be used as a post for single rooted teeth. This post has a retentive

element at the top of the post that will retain composite core material.

1. Prepare canal as above for prefabricated posts paragraphs #1 - #4.

5. CUT THE POST FROM THE BOTTOM SO THAT THE RETENTIVE TOP OF

THE POST IS NO LESS THAN 2MM INFERIOR TO THE OPPOSING

OCCLUSION. The top of the post must be at the top of the preparation or the

composite material will likely break from the top of the preparation.

6. Continue as above until #8.

7. Inject core paste onto the top of the post and into the retentive grooves on the

post.

8. After the core paste has set, prepare the core material to conform to the shape of

the preparation you have already completed.

9. Reline the temporary already completed or make a new temporary restoration

and cement with a non-eugenol containing cement.

Surveyed crown: We strongly recommend the occlusal or cingulum rest seat to be

placed on the metal. Partial denture design should be approved by Prosthodontic faculty

before any crown work starts even if the patient does not have it done concurrently with

crowns.

All ceramic restoration: There is limited use of the all-ceramic restoration in the

Predoctoral program. Most of the anterior crowns are metal ceramic restoration with the

facial/buccal for metal butt joint margin. However, advise to encourage students to do all

ceramic crowns (Procera or E4D).

Laboratory processed fixed provisional restoration: There is limited use of the

laboratory processed fixed provisional restoration. However, if it deems necessary

according to your clinical judgment please advise the student to fabricate his/her own

fixed provisional restoration using the conventional technique first and make a

preliminary impression of all the prepared teeth and mount the casts to be ready to send

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out for laboratory fabrication. This lab processed provisional restoration will be charged

separately from the crown fee. The guideline for this provisional restoration is:

1) Maxillary anterior teeth only when one of the below criteria is met:

a. Esthetically high demand

b. Long term provision: 6 months or more

2) Appropriate Dx wax up has to be completed by the student first and checked/ signed by

a Prosthodontic instructor. The Dx wax up should have all necessary modification from

the initial condition in terms of shape, contour, occlusion, etc. A duplicate of the waxed-

up cast should be sent to a dental lab with the opposing mounted cast.

3) Patients who need this type of provisional restoration will be charged separately from the

final restoration.

Intermediary abutment: Even though the non-rigid connector is rarely used in the

Predoctoral clinic, it may be used according to your discretion. Please consult with Dr.

Weber, Nui, Suzuki, Muftu, D Park, Tsakalelli or Lamberti when you are planning to use

the non-rigid connector.

Elective Endodontic treatment: If you encounter the structurally damaged dentition or

extensive direct restorations that required the complete coverage restoration and your

treatment plan direct to the elective endodontic treatment, dowel/core and complete

coverage restoration, please follow this protocol:

1) Review the treatment record and complete mouth radiographs.

2) Obtain the verification of the complete Prosthodontic treatment plan on the step sheet

with the appropriate approval signature.

3) Evaluate the mounted diagnostic cast.

4) If you are skeptical about the affected tooth condition, please inform student to make an

appointment to evaluate the affected tooth clinically prior to endodontic therapy. We

strongly suggest clinical based evaluation prior to elective endodontic approval.

5) Once the decision has been reached for the elective endodontic treatment, please

inform student, patient, and PC about the result.

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6) For the patient, please spend time describing the advantages, prognosis and potential

risks of the success and failure of the affected tooth according to the definitive treatment

plan as well as the course of treatment and the monetary factor. Please make certain to

inform all patients who will have elective endodontic treatment that the condition of the

affected tooth structure has always been changed at the post-endodontic treatment and

the definitive treatment plan therefore, needs to be re-evaluated at post endodontic

therapy and may be modified.

7) At the time of the endodontic treatment, the condition of the tooth is sometimes

questionable to be restored, please make certain to accommodate the endodontic

faculty members/residents requests to verify the condition of the affected tooth prior to

endodontic treatment.

Long span FPD: The most common span for the FPD accomplished in the Predoctoral

program can be ranged from 3 - 5 unit FPD. This is acceptable. If you encounter the

situation where patients have a strong desire for a long span FPD (5 unit), please see

Dr. Weber, Nui, Suzuki, Muftu, Tsakalelli and D Park. The patient classification can be

found in the memo section.

Custom staining: Porcelain staining kit is available for external staining.

Soldering: When FPD does not fit, there are two main options that most available to

the student (1) cut the metal framework and preceramic soldering (we do not do post

ceramic soldering, which requires special metal framework design) or (2) remake a final

impression.

When encountering a soldering, please make certain to evaluate the

connector of the questionable FPD. Use a thin carborundum disc to section at

the connector. Mid pontic section is preferable, when the connector is thin.

Connect the metal framework with GC pattern resin. Do not pick up

impression at this visit. Send the connected metal framework to the laboratory

for preceramic soldering.

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Try in the soldered metal framework in the mouth and make a pickup

impression with polyether impression material. A new bite registration should

be taken with the metal framework in place. The pickup cast with the metal

framework should be mounted.

Redo/ Remake*: During your teaching, you will be served as a consultant to evaluate

the previous prosthesis which was completed here in the school. When the prosthesis

being evaluated was completed less than 1-2 years, and need to be remade, please

identify the problem associated with your recommendation and advise student to see

Dr. Weber or Nui.

*Definitions for TUSDM:

Redo: When prosthesis must be re-fabricated for an ongoing case due to misfit of the margins, porcelain

fracture during adjustment, occlusal discrepancy or any other reasons related to fabrication of the

prosthesis at the dental laboratory.

Remake: When prosthesis that was finished within the past 3 years must be re-fabricated due to fracture

of the metal or ceramic framework, veneering porcelain, denture tooth/teeth away from the denture base

and/or other parts of prosthesis. Misfit of prosthesis, mismatching of color or problems related with

occlusal habits (bruxing, clenching) would be excluded from ‘Remake’.

Crowns and Bridges or FPD

A. Marginal Discrepancy

Situation 1: A crown fits on the die with no open margin noted, is not under extended

(crown margin not to the edge of the finish line on the tooth) or does not exhibit

an overhang, but the crown does not fit the same way on the tooth/teeth as on

the cast.

Cause: Improper preparation, impression, and/or die ditching

Solution: A new impression must be made and the prosthesis redone. Refining of

the preparation may be required before the impression is made. The

dental laboratory will not be responsible for remaking the crown at no

charge.

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If the problem is due to a narrow finish line of the preparation and so

insufficient thickness for porcelain application, repreparation will be

needed, and then a new impression made.

Situation 2: There is an obvious open margin on a die as well as on the prepared tooth.

Under extended or overhanging margin is noticed.

Cause: Improper fabrication of the crown

Solution: An open margin must be sent back to the lab for re-fabrication only if the

die is intact. If there is not an intact die or impression that can be re-

poured, a new impression must be made. (Polyvinyl impression materials

are more likely to be able to be re-poured than polyether materials)

An overhanging margin may or may not be able to be recontoured at the

chair or school laboratory. Be aware that metal would be exposed after

re-contouring of the porcelain, especially on the anterior PFM crowns.

A slightly under extended margin may have to be remade unless it is

clinically acceptable by a faculty member.

B. Rocking or inadequate lateral stability

Situation 1: A crown fits well and stable on the die. However, the crown rocks when force is

applied buccolingually or mesiodistally on the tooth.

Cause 1: Improper casting – Small nodule inside the crown

Solution: Remove with # ½ or 1 round bur in the clinic.

Cause 2: Improper fabrication – Too much block out (including die spacer) or damage to

the die

Solution: Often needs a new impression.

Cause 3: Improper tooth preparation – Undercuts, irregular finish lines or irregular tooth

surfaces

Solution: Repreparation followed by a new impression

Cause 4: Deformed impression – Indecent manipulation of materials

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Solution: A new impression must be made.

Cause 5: Lack of resistance (Arc of Rotation) – Short crown preparation or over tapered

Solution: Repreparation of the tooth or employment of retention grooves followed by a

new impression

Situation 2: A crown rocks on the die.

Cause 1: Improper fabrication

Solution: Such a crown may be sent back to the lab if the die is intact.

Otherwise, a new impression has to be made.

Cause 2: Short or over tapered tooth preparation

Solution: same as Cause 5 of Situation 1

C. Incomplete seating

Situation 1: A crown fits on the die but it is not seated on the tooth even after adjustment of

the interproximal contacts.

Cause 1: Deformed impression – Indecent manipulation of materials

For example, the impression was put on the table top with the impression

material (Impregum, alginate or VPS) touching it.

Solution: A new final impression should be made.

Cause 2: Improper fabrication of the crown – Metal casting

Solution: A new final impression is recommended.

Cause 3: Undercut on the tooth preparation – Inadequate block out

Solution: Repreparation of the tooth followed by a new impression is recommended.

Also patching a choice of restorative material on the defect or deep undercut of

the tooth surface should be considered. Then refining of the preparation

followed by a new impression should be done. The finish line on the tooth

preparation must be clearly defined at all times.

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Situation 2: A crown is seated after the adjustment of interproximal contacts but now the

interproximal contacts are lost.

Cause 1: Improper path of insertion – Adjacent teeth were not considered

Solution: Repreparation followed by a new impression

Cause 2: Root proximity – Proximal finish line under the proximal surface of the

adjacent tooth

Solution: Refining or lowering of the proximal finish line followed by a new impression

should be done. Also re-contouring of the adjacent proximal surface may be

necessary.

D. Occlusal disharmony (assumed the dental lab is using the same articulator)

Situation 1: The occlusion of both arches is good on the articulator but not in the mouth.

Deviation exists in occlusal contacts between natural dentition and articulator.

Cause 1: Incorrect interocclusal record – Shifting of mandible

Solution: Retake an interocclusal record, remount the casts, and then adjust minor hyper-

occlusion occlusal contact on the articulator. Hypo-occlusion or severe hyper-

occlusion should be sent back to the dental lab.

Cause 2: Incorrect mounting – Indecent technique or careless mounting or dirty

articulator

Solution: Same as Cause 1

Situation 2: Only crown is hypo- or hyper-occluded in the mouth.

Cause 1: Incorrect pindexing

Solution: Previous procedures including a new impression should be repeated.

Cleanliness of the cast should be emphasized.

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Cause 2: Improper die – Reattached broken die, uneven bottom of the die, unfully seated

die, too much superglue around pins, pushed up die during the mounting or by

wax wafer

Solution: Importance of a clean and neat cast should be emphasized.

Pindexing, die ditching, and mounting should be redone.

Situation 3: The crown is hypo- or hyper-occluded even on the articulator.

Cause 1: The dental lab may not use the articulator during fabrication – Hand articulation

likely or remounting on a hinge articulator

Solution: Such a crown may be tried out. However, if it is not occluded properly, it

should be sent back to the dental lab. There should be no marginal discrepancy.

Otherwise, it should be refabricated with a new impression.

Cause 2: There may be discrepancy of a certain degree between their articulator and

student’s articulator.

Solution: The articulator must be free of plaster and wax. Students should be well aware

of how to use the articulator.

RPD: Refer to the articles below

Robert W. Rudd, BS, DDS, MS, CDT,a and Kenneth D. Rudd, BS, DDSb

- A review of 243 errors possible during the fabrication of a removable partial denture: Part I

J Prosthet Dent 2001;86:251-61.

Robert W. Rudd, BS, DDS, MS, CDT,a and Kenneth D. Rudd, BS, DDSb

- A review of 243 errors possible during the fabrication of a removable partial denture: Part II

J Prosthet Dent 2001;86:262-76.

Robert W. Rudd, BS, DDS, MS, CDT,a and Kenneth D. Rudd, BS, DDSb

- A review of 243 errors possible during the fabrication of a removable partial denture: Part III

J Prosthet Dent 2001;86:277-88.

Referral to Postgraduate Prosthodontics: After you have evaluated the overall

definitive treatment plan or tentative treatment plan and realize that the level of the

complexity of the treatment is not appropriate for the predoctroal student, please advise

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him/ her to obtain the referral form and you must consult with the student’s Practice

Coordinator. You must identify the rationale for this referral. Please be certain that after

the patient is referred to the Postgraduate program, it is unlikely that the Predoctoral

program will accept the patient for completion of the treatment unless there is a special

circumstance. Please consult full time faculty member or Dr. Weber or Nui. Please also

make certain to explain to the Predoctoral student the rationale to refer the patient to the

postgraduate clinic to prevent confusion; and try to assist student and Practice

Coordinator to formulate the tentative treatment plan that can be appropriate for the

predoctoral student.

Competency Examination: The competency examination is intended to test the

individual student’s performance on a specific procedure being carried out

independently without any assistance. However, you must inform the student that if

there is any concern in the specific procedure, he or she is strongly advised to get some

advice from the examiner even during the examination. This is to prevent potential

mishap. In the situation where the examiner has foreseen the potential problem or

believes that the selected tooth is inappropriate for the examination procedure, the

examiner is allowed to give advice to the student and has authority to cancel the

examination at this initial stage of examination (Note student will not receive “Failure” in

this situation because the examination has not started). However, the examiner can fail

the student if the outcome is unacceptable during or after examination. The division

would like to have a direct evaluation from the examiner. For the single crown

preparation and provisionalization, student must fabricate the flexible die and submit it

along with the evaluation form to the Department of Prosthodontics and Operative

Dentistry for a final grading.

Transferring the midcase: When you encounter a midcase that needs to be

transferred to another student who is either the lower, upper or same classmate for any

reason, please refer the student to see Dr.Nui, Suzuki or D Park.

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Temporary cementation for FPD: All FPD in the Predoctoral clinic must be

provisionally cemented at least 7-10 days prior to final cementation. No exception.

Insertion of the definitive prosthesis: In certain time such as toward the end of the

semester, the department will send the memo to remind of the last date for delivery.

2) Implant Dentistry

Predoctoral Implant Diagnosis and treatment planning:

Please review the following summary of changes:

1. As you know the Implant Center is no longer involved with the quality control of

predoctoral implant cases (e.g., surgical guide approvals); therefore the Axium

codes 6001A and 6001B have been discontinued. The step sheet has been

redesigned to have Restorative Diagnosis and Treatment Planning, Practice

Coordinator Approval (D00165), Surgical Diagnosis, Treatment Planning (for

Surgical Residents), and Implant Sx Assist (D00166 completion - fulfills predoctoral

student’s MPE requirement) Sections.

2. Once the predoctoral student completes the diagnostic workup (including the

surgical guide) D00165 code will be swiped as “in process” by Drs. Antonellou,

Chaimattayompol (Nui), Del Castillo, Hern, Muftu or Dongwoo Park. Following this

step, the practice coordinator will swipe the same code as “complete.”

3. The predoctoral students will then initiate a surgical consultation with surgical

residents (OMFS, PG Perio, or PG Prostho) along with a surgical faculty member.

At this point, the Surgical Diagnosis and Treatment Planning step will be signed

along with the appropriate case note swiped by surgical faculty.

4. Paula O’Brien will reserve the surgical appointment only if all prior steps on the

implant step sheet have been signed and the code D00165 and appropriate

surgical consultation case note has been swiped to “complete.”

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5. When the predoctoral students attend and assist the implant surgery, Paula

O’Brien will approve the new procedure code D00166 to meet their MPE

requirement. This will free up time for the residents/students and save them

additional paperwork.

6. Since implant treatment is a prosthetically-driven team effort, communication

between all parties involved is crucial. The surgical residents are encouraged to

discuss the case with the predoctoral student and review the plan to make sure the

surgical guide approved by the prosthodontics instructor meets their expectations.

We are confident the residents will continue to work courteously with the

predoctoral students to book the surgery date.

The first section of the step card is for Restorative Diagnosis and Treatment

Planning, which involves (1) initial implant consultation, (2) prosthodontics diagnostic

procedures, (3) surgical guide approval, and (4) Prosthodontics Department approval.

As you may know, the Implant Center is no longer involved in quality control of the

surgical guides. In order to improve efficiency, predoctoral students will work with their

assigned prosthodontics instructors in their groups for steps (1), (2), and (3). It is crucial

that you, as their assigned faculty member are involved with the planning process.

Please ensure the following steps are completed:

Waxups/ tooth setups are done properly.

Dentures that are being duplicated for templates are appropriate (e.g.,

acceptable VDO, CR, tooth position).

Students understand the difference between radiographic and surgical

templates (they are taught this in the preclinic, but may need to a refresher).

The conversion of radiographic template to the surgical template is done

properly (e.g., adequate access present for the surgical pilot drill).

Your name is printed in addition to signing.

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The form is signed only if you are satisfied with the quality of the diagnostic

work.

Department Approval will be completed by Drs. Antonellou, Chaimattayompol

(Nui), Del Castillo, Hern, Muftu, or Dongwoo Park. At this stage, the code

D00165 will be swiped “in process.”

The next step for the students, similar to other prosthodontics treatment

planning processes, is the “completion” D00165 by the Practice

Coordinators.

More information about the revised protocol can be found at iPros. If you have any

questions or suggestions, please do not hesitate to contact me directly

(Ali.Muftu@tufts.edu).

Implant Screwdriver Kits:

a. Students should have the faculty member’s signature on the form to get the kit

from the dispensary.

b. The dispensary personnel will release the kit with the picture of the contents in

the kit for you and the prosthodontic faculty and/or PC to verify the number and

contents of that kit.

c. Each dispensary will have a total of 10 kits. For example on the 3rd floor, Group

1/2 will have 4 kits, Group 3/4 will have 4 kits, the Spare Group 1/2 will have 1 kit

and the Spare Group 3/4 will have 1 kit.

d. You and the faculty member must print and sign your name as well as date and

indicate the clinic session on the picture sheet for a reference.

e. If you find that there is a screwdriver/tool missing upon receipt, please complete

the picture sheet and identify the missing items using the picture sheet as a

guide. The kit with missing items will be returned to the dispensary immediately

for refill and you will receive a new complete kit.

f. After you receive the new complete kit, review and complete the picture sheet

again and return this picture sheet to the dispensary immediately.

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g. At the end of the clinic session, please verify the number and contents by

comparing the picture posted in front of the dispensary.

h. If you find that there is a screwdriver/tool missing upon return, please inform the

dispensary personnel, s/he will look up your previously submitted picture sheet

and add the missing item and initial. If you do not identify to the dispensary that

the kit has a missing item(s), we will be able to identify you from the barcode

system and you will be charged for those missing items. Please be responsible

by not having a kit that is incomplete circulating in the dispensary again.

i. The dispensary personnel will make an order to replace the missing item to that

kit.

j. You will receive an invoice from the clinical affair’s office for the replacement

item(s).

Screw-retained or cement-retained crown or FPD: Screw-retained prosthesis is

strongly recommended as a default type of restoration. Students should bring the

mounted master cast and the template with a screw hole on it. According to this choice,

they will get the implant abutment from ‘Gold Room’ and send it to a dental lab with the

case.

4. Core Procedures for Removable Partial and Complete Dentures

1) The partial denture design approved and signed by a Prosthodontic faculty

member on the step sheet will not be changed when the case is sent out to a

dental lab. Therefore, some advices are followed:

All Prosthodontic faculty members can approve and sign the RPD design.

The path of insertion tripoded on the diagnostic cast by a student must be

verified for proper undercuts and guiding planes of the design before the

step sheet is signed.

The step sheet must be filled out correctly; for instance, the location of rest,

amount and location of the undercut, major connector, clasp name, etc.

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The student must bring surveyor and the surveyed diagnostic casts to

operatory when the mouth preparation is performed.

Alginate impression should be taken and poured up with fast setting plaster

after the mouth preparation. This plaster cast must be surveyed to verify the

rest seats, undercuts and guiding planes. Prosthodontic faculty should now

sign for the mouth preparation procedure on the step sheet. Then, the final

impression can be taken with a choice of material.

Interocclusal record or bite registration must be taken with Regisil or record

base with wax rim if stable occlusion cannot be achieved without it.

If proper undercuts and guiding planes do not exist on the master cast, the

student should ask for help to find the appropriate path of insertion to the

prosthodontic faculty member who worked with him/ her for the mouth

preparation procedure. The faculty member should find a proper path of

insertion for the design and sign the step sheet on #3b. ‘surveyed and

designed’.

2) All master casts for surveyed crowns should be surveyed for the RPD design

when the case is sent out to a dental laboratory. The case will not be sent out

without faculty's approval signature for the RPD design and proper surveying on

the master cast for the surveyed crown. Besides all surveyed crowns must be

verified for the undercut and guiding plane for the RPD design before try-in or

cementation.

3) All master casts for RPD metal framework must be surveyed and the path of

insertion must be tripoded on the cast. Then, the survey lines and outline of the

metal framework should be drawn on the master cast. DO NOT PAINT REST

SEATS WITH RED PENCIL, ONLY OUTLINE.

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4) For a consultation on RPD design, you must bring the mounted casts on the

articulator. Only exception could be when opposing complete denture without a

problem with the interarch distance.

5) Lingualized occlusion is recommended as a default for Complete Denture and/ or

RPD.

6) Due to the significant amount of time the faculty spent in the clinic to re-arrange

the denture tooth setup during the denture tooth try-in clinical visit, we have come

up with a new policy that you shall follow:

Student must obtain the same faculty signature for (a) centric relation

registration, (b) in-lab denture tooth setup procedure and (c) in-clinic denture

tooth try-in visit.

If the primary faculty who signed the centric relation registration is not available,

please contact your prosthodontic group faculty members to review the in-lab

denture tooth setup procedure and follow through with that faculty for the in-

clinic denture tooth try-in visit.

The in-lab denture tooth setup procedure must be signed by Prosthodontic

faculty before denture tooth try-in visit. NO EXCEPTION.

Since the wax denture is approved by the patient, faculty member and you in

the clinic (see the step sheet), it will be sent out to a dental lab without any

modification.

Post dam or posterior palatal seal must be scored on the cast properly before

you send it out.

5. Quality Assurance and Laboratory works

Turn-around policy on Prostheses as follow:

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All Fixed Prostheses and RPD metal frameworks will be returned in 3 weeks,

except for denture processing (2 weeks), repair (24 hours), relining (48 hours),

and cast P & C (1 week).

Single crowns and 3-unit FPDs in many cases may be done to completion

without metal try-in.

Two or more splinted crowns or 4 or more unit FPDs should be done with metal

try-in.

If a 3-unit FPD does not fit, then a new final impression must be made. The

second pour cast of the old impression should not be used.

Metal framework without porcelain can be soldered (Pre-solder). Post-solder is

not recommended.

All interocclusal records must be checked and signed on the step sheet by

faculty.

For a single crown or simple bridge, only a small interocclusal record on the

prepared tooth/ teeth is necessary. DO NOT TAKE A FULL ARCH

REGISTRATION.

All interocclusal record should be trimmed properly to eliminate interferences

preventing from complete sitting on the cast, such as embrasures, occlusal

grooves, and/ or any areas touching the soft tissue.

Regisil is not recommended to be used with wax rim because it is more precise

than wax, it is not seated in right position or bouncing in most cases. Instead,

Alu-Wax is recommended.

Record base with wax rim should be used for the cast with long edentulous span

or no posterior stop. The record base must be made on the cast that will be

mounted because it is not transferable from one cast to another.

Pindexing/ Die ditching or trimming

The master cast should be trimmed in U-shape (15mm high from the margin of

the tooth preparation to the bottom of the cast x 15 mm wide facio-lingually). The

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bottom of the cast should be almost parallel to the occlusal plane and flat without

any voids or irregularities.

At least 2 Pindex pins (one long and one short or two long pins) per medium to

large size of section/ die; 1 BiPin per small size of section/ die recommended.

DO NOT FORGET TO PUT SLEEVES ON TO THE PINS AND TO APPLY

SUPER-SEP BEFORE MAKING BASE.

Use dental stone or Microstone for the base.

Cast mounting

YOUR ARTICULATOR MUST BE AS CLEAN AS POSSIBLE in order to make

the articulator’s interchangeability work out.

The articulator must be clean and free of any plaster, stone or wax.

The movable parts of the articulator such as condylar guide, upper frame, and

centric latch, must be clean and operable.

Upper and lower casts should be fixed together with the interocclusal record by

means of tongue blade and sticky wax/ silicone glue before they are mounted.

DO NOT PUT RUBBER BANDS AROUND THEM. THE RUBBER BAND CAN

PUSH THE CAST SO THE MOUNTING WILL BE ERRONEOUS. AND ALSO

THE CAST MOUNTED IN SUCH A WAY TENDS TO FALL OFF EASILY.

Even if the setting time of mounting stone is 5 minutes according to the

manufacturer, it is advised to leave the mounting at least 30 minutes or more

until the mounting stone sets completely.

Put the blue rubber band around the articulator after placing plaster and closing

the upper frame.

In general, if the mounting has been done right, A) the incisal pin must touch the

incisal table and 2) when the upper cast is unscrewed and held together with the

lower cast in right stable occlusion, the upper frame should be closed onto the

upper cast with no interference without pressing the upper frame.

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Criteria for the evaluation on prostheses from dental laboratories: See the

attached. This criteria may be applied to judge them clinically.