Tooth sensitivity after composite restoration is due to:

Correct answer: C. Excessive drying of the dentin

• A. Excess adhesive may be a concern for pooling and improper curing, but it is not the primary cause of post-op sensitivity.
• B. Inadequate etching reduces bond strength but does not directly cause post-op sensitivity.
• C. Post-operative sensitivity after composite restoration is most commonly caused by OVER-DRYING THE DENTIN. Aggressive drying of dentinal tubules collapses the collagen matrix and removes the moisture needed for the adhesive to bond properly. This creates gaps in the hybrid layer, allowing microleakage and fluid movement in dentinal tubules (hydrodynamic theory) → sensitivity. Correct technique: leave dentin slightly moist ('moist dentin bonding').
• D. While polymerization shrinkage is a contributor to post-op sensitivity, the most commonly TESTED cause on INBDE is excessive dentin desiccation during the bonding procedure.