EFDA Anatomy and Occlusion 2 — Questions and Answers
Question 1: Which cusp of the maxillary first molar is considered the primary centric holding cusp?
- Mesiobuccal cusp
- Distobuccal cusp
- Mesiolingual cusp (Correct answer)
- Distolingual cusp
Correct answer: Mesiolingual cusp
The mesiolingual cusp (cusp of Carabelli's side) is the largest and primary centric holding cusp of the maxillary first molar.
Question 2: The oblique ridge on the maxillary first molar connects which two cusps?
- Mesiobuccal and distolingual
- Distobuccal and mesiolingual (Correct answer)
- Mesiobuccal and mesiolingual
- Distobuccal and distolingual
Correct answer: Distobuccal and mesiolingual
The oblique ridge connects the distobuccal cusp to the mesiolingual cusp, crossing the occlusal surface diagonally.
Question 3: In Angle's Class II malocclusion, how is the mandibular first molar positioned relative to the maxillary first molar?
- Mesial to its normal position
- Distal to its normal position (Correct answer)
- In normal occlusion
- Crossbite relationship
Correct answer: Distal to its normal position
In Class II malocclusion, the mesiobuccal cusp of the maxillary first molar occludes anterior to the buccal groove of the mandibular first molar, placing the mandible distally.
Question 4: Which nerve supplies sensory innervation to the mandibular anterior teeth?
- Inferior alveolar nerve
- Lingual nerve
- Mental nerve
- Incisive nerve (Correct answer)
Correct answer: Incisive nerve
The incisive nerve, a terminal branch of the inferior alveolar nerve, provides sensory innervation to the mandibular anterior teeth and their supporting structures.
Question 5: The cementoenamel junction (CEJ) is significant in periodontics because it marks:
- The boundary of the pulp chamber
- The division between enamel and cementum (Correct answer)
- The location of the alveolar crest
- The attachment of the periodontal ligament to enamel
Correct answer: The division between enamel and cementum
The CEJ marks the anatomical boundary between enamel (crown) and cementum (root), serving as a reference point for measuring attachment levels.
Question 6: Which movement describes the mandible sliding laterally while remaining in contact with the maxillary teeth?
- Protrusion
- Retrusion
- Lateral excursion (Correct answer)
- Centric relation
Correct answer: Lateral excursion
Lateral excursion describes side-to-side movement of the mandible, producing working and balancing side contacts.
Question 7: The anterior teeth are best suited for cutting food primarily due to their:
- Multiple roots and broad crown
- Single root and incisal edge design (Correct answer)
- Large pulp chamber
- Prominent cingulum
Correct answer: Single root and incisal edge design
Anterior teeth have a single root for stability and a thin incisal edge that functions as a cutting blade for incising food.
EFDA Anatomy and Occlusion 2
Which cusp of the maxillary first molar is considered the primary centric holding cusp?