A patient had a composite restoration placed yesterday and reports sensitivity today. What is the MOST likely cause?

Correct answer: A. A high occlusal contact (premature contact) on the new restoration

• A. CORRECT. Sensitivity beginning IMMEDIATELY after placement, especially on biting, is most often a HIGH SPOT. The premature contact concentrates occlusal force on one point, producing PDL inflammation (hence pain on biting and percussion) and pulpal hyperemia. It is checked with articulating paper in centric AND excursive movements and corrected in seconds — always the first thing to rule out because it is quick, free, and common.
• B. Recurrent caries under a one-day-old restoration is not plausible.
• C. Necrosis takes time to develop and produces spontaneous, lingering, often nocturnal pain rather than immediate post-op sensitivity.
• D. Debonding usually presents later with marginal staining, marginal leakage, or the restoration coming loose — not next-day sensitivity.

Note: Post-op composite sensitivity checklist: high spot first, then check for polymerization shrinkage/gap, inadequate cure, over-etched dentin, or missing liner in a deep prep.