Question

A Class II MO restoration placed on a maxillary first premolar presents with a cervical overhang. What is the most likely anatomical reason for this?

• A. Mesial marginal developmental groove
• B. Canine eminence/fossa
• C. Stippling
• D. Mesial concavity

Hint:

Maxillary first premolar has a mesial marginal developmental groove that can predispose to cervical overhangs if matrix adaptation is improper.

Answer 1

The Correct Option is A

Step 1: Understand the tooth anatomy involved.
The maxillary first premolar has a unique anatomical feature on its mesial surface called the mesial marginal developmental grooveThis groove crosses the marginal ridge and extends onto the proximal surface
Step 2: Clinical relevance in Class II MO restoration.
During preparation and restoration of a mesio-occlusal (MO) cavity, this developmental groove creates an irregular contour at the cervical areaIf not properly adapted with a matrix band and wedge, restorative material may extend into this groove resulting in a cervical overhang
Step 3: Evaluation of other options.
(B) Canine eminence/fossa: Related to anterior tooth anatomyNot relevant to premolars
(C) Stippling: Refers to gingival surface textureNot related to cervical overhang formation
(D) Mesial concavity: Although present, the most significant cause of overhang in this specific tooth is the mesial marginal developmental groove
Step 4: Conclusion.
Therefore, the most likely anatomical reason for a cervical overhang in a Class II MO restoration on a maxillary first premolar is the mesial marginal developmental groove