AGD Fixed and Removable Prosthodontics 2 — Questions and Answers
Question 1: Which impression material is most appropriate for capturing fine detail in a full-arch fixed prosthesis preparation?
- Zinc oxide eugenol paste
- Polyvinyl siloxane (PVS) (Correct answer)
- Irreversible hydrocolloid (alginate)
- Zinc phosphate cement
Correct answer: Polyvinyl siloxane (PVS)
Polyvinyl siloxane offers excellent dimensional stability, detail reproduction, and tear resistance, making it the gold standard for final impressions in fixed prosthodontics.
Question 2: A patient presents with a Kennedy Class II partial edentulous arch. How many modification spaces are allowed before the classification changes?
- One modification space (Correct answer)
- Two modification spaces
- Three modification spaces
- No modification spaces are allowed
Correct answer: One modification space
Kennedy Class II (unilateral distal extension) allows only one modification space; a second modification would change the classification.
Question 3: What is the primary purpose of a surveyor in removable partial denture (RPD) design?
- To measure interocclusal distance
- To determine the path of insertion and identify undercuts (Correct answer)
- To fabricate the metal framework
- To evaluate periodontal bone loss
Correct answer: To determine the path of insertion and identify undercuts
A dental surveyor identifies the path of insertion, measures undercut depth, and helps design retentive and reciprocal components of an RPD.
Question 4: Which type of connector in an RPD framework crosses the midline and joins the bilateral components?
- Minor connector
- Major connector (Correct answer)
- Rest seat
- Retentive arm
Correct answer: Major connector
The major connector (e.g., palatal bar or lingual bar) crosses the midline and rigidly joins all components of the RPD framework.
Question 5: During crown preparation for a posterior full-coverage restoration, which axial reduction guideline is most appropriate for a metal-ceramic crown?
- 0.3–0.5 mm facial reduction
- 1.5–2.0 mm facial reduction (Correct answer)
- 3.0–3.5 mm facial reduction
- No facial reduction is required
Correct answer: 1.5–2.0 mm facial reduction
Metal-ceramic crowns require approximately 1.5–2.0 mm of facial (buccal) reduction to accommodate both the metal coping and the porcelain layer.
Question 6: Which occlusal scheme is typically recommended for complete denture patients?
- Mutually protected occlusion
- Group function occlusion
- Lingualized occlusion or bilateral balanced occlusion (Correct answer)
- Canine-guided occlusion
Correct answer: Lingualized occlusion or bilateral balanced occlusion
Bilateral balanced occlusion or lingualized occlusion distributes occlusal forces evenly during all excursive movements, reducing denture instability.
Question 7: A patient's complete maxillary denture exhibits a 'clicking' sound during speech. Which denture fault is most likely responsible?
- Insufficient freeway space (vertical dimension of rest not maintained)
- Excessive vertical dimension of occlusion (Correct answer)
- Over-extended posterior border
- Inadequate post-dam seal
Correct answer: Excessive vertical dimension of occlusion
Excessive vertical dimension of occlusion reduces freeway space, causing the teeth to contact during speech and producing a clicking sound.
AGD Fixed and Removable Prosthodontics 2
Which impression material is most appropriate for capturing fine detail in a full-arch fixed prosthesis preparation?