MFDS Clinical Dental Sciences 1 — Questions and Answers
Question 1: The periodontal probe reading indicating moderate periodontitis is a pocket depth of:
- 1–3 mm
- 4–6 mm (Correct answer)
- 7–9 mm
- >10 mm
Correct answer: 4–6 mm
Pocket depths of 4–6 mm typically indicate moderate periodontitis; readings >7 mm are associated with severe periodontitis according to the 2017 AAP/EFP classification.
Question 2: The BEWE (Basic Erosive Wear Examination) score of 3 indicates:
- No erosion
- Initial loss of surface texture
- Hard tissue loss <50% of surface area
- Hard tissue loss ≥50% of surface area (Correct answer)
Correct answer: Hard tissue loss ≥50% of surface area
BEWE score 3 indicates severe erosive wear with hard tissue loss of 50% or more of the surface area, often exposing dentine extensively.
Question 3: When carrying out a direct pulp cap, which material is currently considered the gold standard?
- Zinc oxide eugenol
- Calcium hydroxide
- Mineral trioxide aggregate (MTA) (Correct answer)
- Glass ionomer cement
Correct answer: Mineral trioxide aggregate (MTA)
MTA has become the gold-standard pulp-capping material due to its superior biocompatibility, sealing ability and consistent promotion of tertiary dentine bridge formation compared to calcium hydroxide.
Question 4: The 'rule of twos' in endodontics refers to:
- Canals should be cleaned in two stages
- Working length to be confirmed with two radiographs (Correct answer)
- Use two rotary files minimum
- Two-appointment protocol for necrotic teeth
Correct answer: Working length to be confirmed with two radiographs
The 'rule of twos' recommends confirming working length radiographically at two stages (initial and master cone) to ensure accuracy in root canal treatment.
Question 5: The functional unit of the periodontium that suspends the tooth in the socket is the:
- Alveolar bone proper
- Cementum
- Periodontal ligament (Correct answer)
- Epithelial attachment
Correct answer: Periodontal ligament
The periodontal ligament is the fibrous connective tissue structure running between cementum and alveolar bone that suspends and supports the tooth during function.
Question 6: In Angle's classification, a Class II division 2 malocclusion is characterised by:
- Proclined upper central incisors
- Retroclined upper central incisors and a deep overbite (Correct answer)
- Upper arch narrow with crowding
- Anterior crossbite
Correct answer: Retroclined upper central incisors and a deep overbite
Class II division 2 features a Class II skeletal relationship with retroclined upper central incisors (and sometimes proclined laterals), typically producing a deep overbite.
MFDS Clinical Dental Sciences 1
The periodontal probe reading indicating moderate periodontitis is a pocket depth of: