Prosthodontics: Fixed and Removable Assist Practice Questions
22 free Prosthodontics: Fixed and Removable Assist practice questions for the CDA. Tap an option to answer — you get instant feedback, the correct answer, and a detailed explanation for every question.
What is the main distinction between fixed prosthodontics and removable prosthodontics?
- A Fixed prosthodontics uses only acrylic, while removable uses a rigid cast metal framework throughout
- B Fixed prostheses cannot be removed by the patient, while removable ones come out daily
- C Fixed prosthodontics only replaces single teeth, whereas removable replaces multiple teeth
- D Fixed prostheses are always implant-supported, removable are tooth-supported
Correct answer: Fixed prostheses cannot be removed by the patient, while removable ones come out daily
Fixed prostheses (like crowns and bridges) are permanently cemented and cannot be removed by the patient, whereas removable prostheses (like dentures and partials) are designed to be taken out daily. This is the fundamental difference between the two branches.
Which of the following is a common indication for removable partial denture treatment?
- A A single anterior tooth missing with fully healthy adjacent teeth present
- B An edentulous mandible with no dental implants being planned
- C Multiple missing teeth in one quadrant with suitable abutments
- D Need for a permanent replacement of a single fractured tooth
Correct answer: Multiple missing teeth in one quadrant with suitable abutments
When multiple teeth in the same quadrant are missing and there are suitable abutment teeth, a removable partial denture is often indicated to replace those teeth.
During a crown preparation appointment for fixed prosthodontics, what role might a dental assistant perform?
- A Decide on the final shade of the crown restoration for the patient
- B Place gingival retraction cord before the final impression
- C Cement the definitive crown permanently
- D Take radiographs to determine root length
Correct answer: Place gingival retraction cord before the final impression
A dental assistant commonly assists in placing gingival retraction cord to expose margin for a detailed final impression before sending the case to the lab. Shade selection and cementation are typically dentist responsibilities.
What is the purpose of a face-bow in fixed prosthodontics?
- A To measure tooth color for accurate shade matching before crown work
- B To mount casts on an articulator with maxilla-mandible relation
- C To take the final working impressions of the prepared teeth
- D To assess bone density before crown placement
Correct answer: To mount casts on an articulator with maxilla-mandible relation
A face-bow records the spatial relationship of the maxillary arch to the temporomandibular joints so casts can be mounted correctly on an articulator, aiding in accurate occlusion and prosthesis fabrication.
Which material is traditionally used as a luting agent for cementing fixed crowns and bridges?
- A Alginate
- B Zinc phosphate cement
- C Wax rim material
- D Polyether impression material
Correct answer: Zinc phosphate cement
Zinc-phosphate cement has been one of the oldest and most widely used conventional luting agents for cementing casts such as crowns and bridges.
Which instrument would be most appropriate for smoothing and polishing a newly fabricated denture base before delivery?
- A Endodontic file
- B Low-speed handpiece with polishing bur/disc
- C High-speed bur used for crown preparation
- D Scaler
Correct answer: Low-speed handpiece with polishing bur/disc
A low-speed handpiece with polishing burs or discs is used to finish and polish prosthetic appliances such as denture bases before delivery to the patient, preventing rough surfaces that irritate tissues.
When delivering a removable partial denture, which of the following tasks should the assistant assist with?
- A Polish the denture and instruct on insertion, removal, and care
- B Select the colour of the artificial teeth for the framework
- C Perform the final try-in occlusion verification fully independently
- D Choose the metal alloy used for the denture framework
Correct answer: Polish the denture and instruct on insertion, removal, and care
As part of delivery, the assistant helps polish the denture and gives the patient instructions on how to insert, remove and care for their new prosthesis — ensuring comfort and hygiene.
What is a major contraindication for fixed bridge prosthesis according to prosthodontic treatment planning principles?
- A Presence of suitable abutment teeth
- B Good oral hygiene and healthy supporting tissues
- C Poor periodontal health of abutment teeth
- D Patient motivation for permanent restoration
Correct answer: Poor periodontal health of abutment teeth
Poor periodontal health of abutment teeth undermines the support and longevity of a fixed bridge, making it a contraindication for fixed prosthesis.
Which prosthetic restoration replaces all the teeth in an arch and can be removed by the patient at will?
- A Fixed partial denture
- B Implant-supported crown
- C Complete denture
- D Inlay restoration
Correct answer: Complete denture
A complete denture is a full-arch removable prosthesis used when all teeth in an arch are missing; the patient can remove it anytime for cleaning.
What is the role of a diagnostic wax-up or trial prosthesis in removable prosthodontics planning?
- A To permanently replace all the missing teeth right away immediately
- B To evaluate aesthetics, occlusion, and speech before fabrication
- C To cement onto the remaining teeth for temporary added support
- D To cure the acrylic resin for the final denture
Correct answer: To evaluate aesthetics, occlusion, and speech before fabrication
A diagnostic wax-up or trial prosthesis allows evaluation of aesthetics, occlusion, and phonetics, giving both dentist and patient a preview before final denture fabrication.
In fixed prosthodontics, what is a core build-up used for?
- A To fabricate a full removable denture
- B To strengthen and recreate tooth structure before crown placement
- C To record jaw relations for articulator mounting
- D To take preliminary impressions
Correct answer: To strengthen and recreate tooth structure before crown placement
A core build-up is used when a tooth has lost significant structure (e.g., large cavity or after endodontic treatment) — it rebuilds tooth form to support a crown.
Which component of a removable partial denture provides retention and prevents displacement during function?
- A Artificial teeth
- B Major connector
- C Clasp (retainer)
- D Denture base resin
Correct answer: Clasp (retainer)
The clasp or retainer partially encircles an abutment tooth and provides retention by resisting dislodging forces during chewing or movement.
When is gingival retraction cord typically placed during a fixed crown procedure?
- A Before tooth preparation
- B Immediately after cementing the crown
- C Just before taking the final impression
- D After polishing the crown
Correct answer: Just before taking the final impression
Retracting gingival tissues just before the final impression ensures that the margin of the preparation is exposed, allowing the impression material to capture accurate detail for a well-fitting restoration.
Why might a removable denture be more suitable than a fixed bridge for some patients?
- A Because removable dentures are always more stable
- B If the patient has few or no suitable abutment teeth
- C Because removable dentures never require adjustments
- D If the patient prefers a permanent, non-removable solution
Correct answer: If the patient has few or no suitable abutment teeth
When a patient lacks adequate abutment teeth to support a fixed bridge, a removable denture becomes a more appropriate choice for replacing missing teeth.
Which statement is correct regarding the use of articulators in prosthodontics?
- A They are used during the patient's chairside impression taking appointment
- B They are devices replicating jaw movements for accurate prosthesis work
- C They are only used for removable dentures, not fixed prosthetics
- D They permanently hold the final prosthesis in place
Correct answer: They are devices replicating jaw movements for accurate prosthesis work
Articulators simulate the mandibular movements relative to the maxilla, helping in designing restorations (fixed or removable) with proper occlusion and function.
Which of the following is NOT considered part of the laboratory-related tasks for fixed prosthodontics workflow?
- A Pouring and trimming the diagnostic study casts in the lab
- B Fabrication of the wax-up and final crown or bridge casting
- C Cementation of the definitive prosthesis in the mouth
- D Articulation of the casts to check occlusal contacts
Correct answer: Cementation of the definitive prosthesis in the mouth
Cementation of the final prosthesis is done clinically, not in the lab. The other tasks — casting, waxing, pouring casts, and articulation — are lab-related procedures.
During delivery of a full denture, what should a dental assistant advise the patient regarding overnight care?
- A Leave the denture in mouth overnight to help adaptation
- B Store the denture in water or a moist container when not wearing it
- C Clean it with bleach daily
- D Heat the denture before wearing each morning
Correct answer: Store the denture in water or a moist container when not wearing it
When not wearing, dentures should be stored in water or a moist container to prevent warping and maintain their shape and fit.
Which of the following could be a reason to choose a fixed crown over a removable partial denture?
- A Patient has many missing teeth across the arch
- B Need for easy daily removal and cleaning
- C Replacement of a single badly damaged tooth
- D Desire to reduce overall treatment cost
Correct answer: Replacement of a single badly damaged tooth
For a single, badly damaged tooth with healthy surrounding teeth, a fixed crown is often preferred as it provides permanent coverage and strength. Removable partial dentures suit multiple missing teeth.
What is the purpose of a wax rim in removable denture fabrication?
- A To permanently secure the denture base
- B To record vertical dimension of occlusion and jaw relations
- C To polish the final denture before delivery
- D To cement the final teeth into the base
Correct answer: To record vertical dimension of occlusion and jaw relations
A wax rim is used during jaw relation records to help establish correct vertical dimension of occlusion (VDO) and the proper maxilla-mandible relationship before denture processing.
Which factor must be evaluated carefully before recommending any prosthesis (fixed or removable) to a patient?
- A The patient's chronological age at the time of treatment only
- B The total number of missing teeth in the arch only
- C Health of tissues, oral hygiene, and patient motivation
- D The colour and shade of the existing natural teeth only
Correct answer: Health of tissues, oral hygiene, and patient motivation
Successful prosthodontic treatment depends on healthy supporting tissues, the patient’s oral hygiene habits, and motivation to maintain the prosthesis; neglecting these can lead to failure.
Why might a provisional (temporary) crown be placed before the final crown is cemented?
- A To improve chewing efficiency permanently
- B To maintain tooth position and protect prepared tooth until final restoration is ready
- C To whiten the tooth before final crown
- D To test the patient’s allergy to crown materials
Correct answer: To maintain tooth position and protect prepared tooth until final restoration is ready
A provisional crown protects the prepared tooth structure, maintains occlusion and tooth position until the final restoration is fabricated and cemented. It is a temporary safeguard.
Which statement is true regarding patient instructions for care of a new removable denture?
- A You should never remove the denture from the mouth, even for cleaning
- B Clean the denture daily and brush the natural teeth separately
- C Soak the denture in hot boiling water to sterilize it daily
- D Use abrasive toothpaste to polish the denture surface
Correct answer: Clean the denture daily and brush the natural teeth separately
Proper denture hygiene involves daily cleaning of the denture and separate brushing of natural teeth and abutment teeth to prevent decay and periodontal issues. Hot water or abrasive toothpaste can damage the prosthesis.