Each of the following dental anomalies typically affects the ANTERIOR teeth EXCEPT:

Correct answer: D. Concrescence

• A. The peg lateral is the archetypal localised microdontia and affects the MAXILLARY LATERAL INCISOR, along with the third molar.
• B. Dens invaginatus is overwhelmingly a lesion of the MAXILLARY LATERAL INCISOR — the single most affected tooth in the mouth.
• C. Gemination (an attempted split of a single tooth germ) is most common in the ANTERIOR maxilla, particularly the incisor region, in both dentitions.
• D. CORRECT — this is the exception. CONCRESCENCE is the union of two adjacent teeth by CEMENTUM ONLY, without dentin confluence. It is a POSTERIOR phenomenon, classically involving the MAXILLARY SECOND AND THIRD MOLARS, and is usually attributed to crowding or trauma causing the roots to be joined by excess cementum after root formation. It is often discovered only when an extraction unexpectedly removes two teeth.

Note: Fusion vs gemination vs concrescence: FUSION joins two separate germs through DENTIN, so the tooth count is one fewer. GEMINATION splits one germ, so counting the anomalous tooth as one gives a normal count. CONCRESCENCE joins only by CEMENTUM, occurs after roots form, and is a maxillary molar finding.