Fixed & Removable Prosthodontics Exam Review

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Questions and Answers

What is the purpose of checking proximal contacts before evaluating marginal fit?

To assess the aesthetics of the crown

To avoid tight proximal contacts hindering assessment (correct)

To identify potential occlusion issues

To ensure the crown can be seated properly

Which type of margin issue is indicated by an improperly trimmed die?

Over-extended margin (correct)

Over-contoured margin

Open margin

Under-extended margin (correct)

What is a common cause of an over-contoured crown margin?

Poor impression

Over-polished casting

Incomplete casting

Surplus untrimmed wax (correct)

Which of the following is NOT an objective of modifying abutment tooth contours?

Increase the thickness of the crown Signup and view all the answers

What tool is recommended for checking the marginal fit of the crown?

Explorer Signup and view all the answers

Which condition is often associated with an open margin?

Poor impressions Signup and view all the answers

Why is it important to assess aesthetics when modifying abutment contours?

To fulfill patient preferences Signup and view all the answers

What is the role of articulation paper in crown evaluation?

To assess occlusion Signup and view all the answers

What is one of the main indications for placing a dental crown?

Protection of the remaining tooth structure Signup and view all the answers

Which type of crown is considered the most conservative option?

Zirconia (monolithic) Signup and view all the answers

In terms of axial tooth reduction, what is the maximum reduction for a zirconia crown?

1mm-1.5mm Signup and view all the answers

What is the recommended occlusal reduction for an all metal crown?

1mm-1.5mm Signup and view all the answers

Which of the following crown types may be used to alter the occlusal plane?

Any type of crown Signup and view all the answers

What amount of incisal reduction is advised for a ceramic crown?

1.5mm-2mm Signup and view all the answers

How much occlusal reduction is necessary when preparing a crown for posterior teeth?

1.5mm-2mm Signup and view all the answers

Which statement regarding crowns is correct?

Crowns can act as abutments for removable partial dentures Signup and view all the answers

What is the main goal of the reorganized approach in occlusion management?

To make large changes to the occlusion Signup and view all the answers

Which position describes the most tooth-to-tooth contact for an individual?

Intercuspal position (ICP) Signup and view all the answers

Which of the following is NOT a type of tooth surface loss?

Hypoplasia Signup and view all the answers

What is the purpose of an articulated study cast in dental management?

To plan the restoration of the original shape of teeth Signup and view all the answers

Which of the following is an indication for the use of a hard splint?

Managing bruxism Signup and view all the answers

In the context of tooth wear, how does erosion differ from attrition?

Attrition involves the loss of tooth structure due to contact, whereas erosion is due to acid dissolution Signup and view all the answers

During a clinical examination for tooth wear, which of the following should be emphasized?

Intra-oral examination findings Signup and view all the answers

What does a soft splint primarily do for a patient?

Offers cushioning to alleviate pressure Signup and view all the answers

What is the primary advantage of using bonded cements over non-bonded cements?

They dissipate forces from the interface. Signup and view all the answers

Which of the following materials is noted for its difficulty in achieving adhesion with traditional techniques?

Zirconia Signup and view all the answers

What technology is currently being explored to improve bonding with zirconia?

Surface modification methods Signup and view all the answers

What is the consequence of using prophy paste on tooth preparations before cementation?

It can negatively affect the bond strength. Signup and view all the answers

What characteristic differentiates zirconia from conventional silica-based materials?

Zirconia requires aggressive mechanical abrasion for surface roughness. Signup and view all the answers

Which type of cement is suggested for zirconia restorations under ideal conditions?

Resin-modified glass ionomer (RMGI) cement Signup and view all the answers

What type of bonding agent should be used on zirconia restorations before cementing?

A bonding agent applied on both tooth and internal restoration Signup and view all the answers

Which specific monomer is recommended for achieving a chemical bond with zirconia?

10-MDP Signup and view all the answers

What is the maximum angle of non-parallelism allowed in tooth preparation walls for optimal cementing?

20 degrees Signup and view all the answers

What is a potential downside of increasing surface roughness on zirconia?

It may create strength-reducing surface flaws. Signup and view all the answers

What is the primary purpose of a dental post?

To anchor a core in a non vital tooth Signup and view all the answers

Which of the following is NOT a role of splints in dental treatment?

To replace a missing tooth Signup and view all the answers

What should be avoided during the cementation process to maintain bond strength?

Contact of phosphoric acid with zirconia Signup and view all the answers

Which of the following cements is known for its compatibility with zirconia ceramics?

Panavia V5 Signup and view all the answers

What is the primary function of a core in dentistry?

To provide substructure to retain the final restoration Signup and view all the answers

Which property of RMGI cements is recognized among clinicians?

Weaker bond in acidic environments Signup and view all the answers

What is the main purpose of primers containing 10-MDP when used with zirconia ceramics?

To facilitate chemical bonding. Signup and view all the answers

What type of primer can promote adhesion of alumina and zirconia to restorations?

Metal/Zirconia Primer Signup and view all the answers

What process is used to confirm that a patient is in their Retruded Condylar Position (RCP)?

Taking articulated study casts Signup and view all the answers

What is a common basis for the recommended height of tooth preparations when cementing zirconia restorations?

At least 4 mm in height from the gingival margin Signup and view all the answers

What is a common material used to create a silicone index?

Optosil P Signup and view all the answers

What structure is reinforced by the use of a dowel in a tooth?

Radicular portion Signup and view all the answers

In which scenario would a splint NOT be recommended?

To permanently anchor a bridge in place Signup and view all the answers

Which procedure involves creating diagnostic wax-ups to conform to aesthetic prescriptions?

Restoring anterior teeth with composite Signup and view all the answers

Study Notes

Course Information

Course Title: Fixed & Removable Prosthodontics
Course Code: DES410
Faculty: Dr. Christos Theocharides and Dr. Alexandros Panayiotou
Institution: European University Cyprus, School of Dentistry

Exam Format

20 multiple choice questions (MCQs): 10 fixed, 10 removable; each worth 1 mark. Each MCQ has 5 options, only one is correct.
10 short answer questions (SAQs): 5 fixed, 5 removable; each worth 4 marks.
Questions are primarily clinical-based. Review year 3 notes and clinical guidelines for preparation.
Carefully read each question before answering.

Dental Crowns

Indications: Protect remaining tooth structure, alter aesthetics, facilitate removable partial denture construction, alter occlusal plane.
Types (from least to most destructive): Zirconia (monolithic), all-metal crown, all-ceramic crown, ceramo-metal crown, porcelain fused to zirconia.

Tooth Reductions

A table details reductions for different materials based on occlusal (posterior) and incisal (anterior) areas of the tooth.

Crown Preparation (Steps)

Take shade of crown (if porcelain or zirconia).
Take two or three putty indices.
Apply local anesthetic if required.
Prepare tooth (use guide indices).
Fabricate temporary crown.
Place retraction cord with a hemostatic agent.
Take an impression.
Place temporary crown.
Check occlusion and adjust if needed.
Complete records and laboratory card.

One Stage Impression Technique

Select appropriate tray, apply adhesive to tray (following manufacturer's instructions).
Ensure any undercuts in the mouth are blocked appropriately (using wax if needed).
Have assistant load heavy-bodied material into the tray (using green/blue mixing tip).
Simultaneously, use a syringe with light-bodied material (yellow mixing tip) to irrigate around the prepared teeth.
Firmly hold the tray in the mouth until the impression sets. Do not leave it in too long to avoid trapping undercuts.
Remove, rinse and disinfect following manufacturer's recommendations.

Inspection of Impression Quality

Rinse and clean impression to remove saliva and blood.
Dry and check using 3-in-1 tool and light/magnification.
Disinfection according to manufacturer's instructions.
Check preparation margins, tooth morphology, air bubbles.
Ensure impression material is still attached to impression tray.
Complete and submit lab form, signed by supervisor.

Crown Cementation (Steps)

Verify lab work, including fit and shade.
Remove temporary restoration.
Clean the underlying prepared tooth.
Try in the restoration.
Check marginal fit, contact points, and occlusion.
Verify patient's satisfaction with fit and appearance.
Remove crown and clean both crown and tooth surfaces.
Sandblast with aluminum oxide (50µm) if indicated.
Cement with proper cement, remove excess.
Recheck occlusion.

Cements or Luting Agents

Summarizes cements based on soft (temporary) versus permanent (hard) categories. Includes different types within each category, e.g., provisional restorations, acid-base reaction.

Choosing the Right Cement (Luting or Bonding)

The weaker restoration material, the stronger the cement.
Bonded cements disperse forces away from the interface.
Correct amount of retention needed (preparation form, tapers, crown/wall length) is crucial.

Non-Silicate Ceramics (Zirconia)

Zirconia-based components are difficult to bond to synthetic or natural tissues.
Traditional adhesive techniques for silica-based ceramics do not work effectively with zirconia.
Modifications to the surface of zirconia might improve adhesive bonding.

Physical Properties of Zirconia

Zirconia's composition and physical properties differ from conventional silica-based materials (e.g., porcelain).
Zirconia is not easily etched, requiring aggressive mechanical abrasion methods to improve surface roughness, possibly creating strength reduction flaws.

Recommended Cements for Zirconia Ceramics

Resin cements containing 10-MDP (methacryloyloxydecyl dihydrogen phosphate) can chemically bond with zirconia.
Examples include Panavia V5, SE Bond, or SA Luting.

Some Tips

Avoid phosphoric acid contact with zirconia during cementation.
Do not use prophy paste for cleaning tooth preparations. Use pumice and water.
Use resin-modified glass ionomer (RMGI) cement for zirconia restorations when preparations have near-ideal characteristics.
Ensure tooth preparation height (at least 4mm) from the gingival margin to the occlusal table.

Permanent Cements

Provides a table categorizing permanent cements in terms of type and their applications/strengths/weaknesses.

Articulating Papers

Used to check occlusal contacts in crowns, dentures, provisional, and definitive restorations.
Explains different types of articulating papers regarding thickness and common uses.

Treatment Planning Process

Describes a three-phase model: Emergency, Investigation/Stabilization, Rehabilitation, and Maintenance.

Clinical Case Scenario

A patient with severe decay and irreversible pulpitis on tooth #46 is described. The student needs to determine the management approach.

Emergency Phase

Emergency cases (acute pain) entail either RCT or extraction (if unrestorable), especially if multiple carious cavities and active periodontal disease exist.

Stabilization Phase

Treat carious cavities and stabilize periodontal disease.
Complete RCT on tooth #46 in some cases.

Rehabilitation Phase

Restoration focus on prosthetic stage and restoring all affected teeth.

Maintenance Phase

Set patient recall intervals for checkups and hygiene.

Common Errors Affecting Marginal Fit

Tight proximal contacts.
Casting blebs.
Over/under-extended crown margins.
No die spacer.
Impression distortion.

Checking the Fit of the Crown

Visual: Check margins (directly or with mirror), use magnification.
Instrumental: Use explorer probes with different sizes and angles of approach for subgingival margins.

Types of Defective Margins

Describes different types of poor marginal fits, including over-extended, under-extended, over-contoured, and open margins.

Evaluating the Crown Prior to Cementation

Check proximal contacts (use floss).
Check marginal fit (use explorer).
Check both shape and shade.
Check occlusion (use articulating paper).

Semi-Precision Attachments

A section on semi-precision attachments.

Objectives of Modifying Abutment Tooth Contours

Develop a suitable path of insertion.
Promote favorable biomechanical properties.
Improve aesthetics.
Improve structural durability.

Options for Replacing Teeth

Describes several common options (fixed, removable).
Includes examples of different materials/designs used in these approaches.

Factors Affecting Prognosis of Teeth

Patient Factors: Restorative (endodontic, periodontal, and structural), medical, dental and social factors, expectations, financial status, behavior.
Dentist Factors: Experience, skills, training, available materials & equipment.

Prognosis

Structural Integrity: Requires at least 1.5mm ferrule, and dentin needs more than 1mm thickness, especially for root-treated teeth.
Endodontic Integrity: Predictable outcomes require healthy pulps/clean/obturated root canals.
Periodontal Integrity: Bone loss and tooth mobility influence prognosis.

Strategic Value of a Tooth

Aesthetics, medical, occlusal, prosthodontic, functional, and financial impacts.

RCP and ICP

RCP: Bilateral, unstrained mandible position where tooth-to-tooth contact occurs/reproductive position for the occlusion when restoring multiple units.
ICP: Position of most tooth-to-tooth contact for individual's occlusion.

Management of Teeth with Extensive Tooth Loss

An overview of management strategies.

Toothwear

What to check in a clinical exam (Presenting complaint, medical history, social history, diet history, extra-oral and intra-oral exam, wear identification, sensitivity tests, radiographs, prosthodontic assessment.

Types of Tooth Surface Loss

Attrition, abrasion, erosion, abfraction, caries, iatrogenic, and trauma.

How to Manage Wear Cases

Questions addressed: What type of wear? Treatment approach? If restoring shape, plans, materials used, and need for splints. Types and function of splints.

Clinical Features of Attrition and Erosion

Attrition: Flattening of cusps, wear facets, fractures, hypersensitivity, surface loss not related to articulation, possible masseteric hypertrophy/tenderness.
Erosion: Smooth/shiny enamel loss, deep cupping.

Management of TSL

A summary of management options ordered from most to least conservative.

How to Manage a Patient with TSL from Erosion - most conservative to most destructive

Diet analysis and change recommendations.
Fluoride toothpaste and teeth protection recommendations.
Composite resin restorations are a key repair option for function and aesthetics.
Indirect lab-made restorations can restore worn-down teeth.
Splints are not recommended for active erosion cases.

How a Wear Case is Managed

Take articulated study casts in centric relation (CR).
Fabricate wax-ups.
Demonstrate the wax-up/restoration to patient.
Make a putty index or plastic retainer.
Use composite resin to restore the upper anterior teeth.

Role of Splints

To test an increase in occlusal vertical dimension, in case of TMD, before and after restorative therapy.
To evaluate patient positioning in RCP (Centric Relation Position).
To treat TMD patients with muscle origin pain.
To assess patients who may use partial dentures/overdentures/onlays.

Posts and Cores

Post: A metal or rigid material placed in the root canal of a non-vital tooth to support a dental restoration.
Core: A substructure replacing missing coronal tooth structure that supports the final restoration.
The presence of sufficient natural tooth structure helps anchor a dental. If suitable, no post needed.

How to Decide on Post Type: Direct/Indirect

Guide for determining the best option (direct or indirect) based on ferrule height.

Differentiating Indirect and Direct Methods

Indirect: Post/core fabrication in the lab, often using a cast post.
Direct: Post/core fabrication at the chairside, often involving fiber composite material.
Indirect Method: Wax or duralay representation is sent to lab for fabrication

Questions: What is ideal length of a post?

A guide about how to select the ideal post length related to ferrule and the amount of dentin remaining.

Tooth Restorability Index (TRI)

Structure: Tooth divided into 6 sextants (two proximal, two buccal, two lingual).
Scoring: Scores 0-3 in each sextant (0 being the least restorable, 3 the most restorable). Maximum is 18 per tooth.
Clinical Decision: A tool for evaluating tooth restorability based on the remaining tooth structure (remaining coronal tissue).
Levels of adequacy: None, inadequate, questionable, and adequate.
TRI Score: Guide for the clinician in determining if the tooth is suitable for a certain treatment.

Clinical Decision based on TRI Score

A table based on TRI Score that helps determine the suitability for treatment options.

Revision Advice

Read lectures, lab sessions and clinical guidelines.
Use the revision lecture as a guide and pay attention to details.

Studying That Suits You

Use AI to generate personalized quizzes and flashcards to suit your learning preferences.

Description

Prepare for the Fixed & Removable Prosthodontics exam with a comprehensive quiz covering clinical indications, types of dental crowns, and tooth reductions. This quiz includes multiple choice and short answer questions to test your knowledge and understanding. Make sure to review your year 3 notes and clinical guidelines thoroughly for a successful exam experience.