Excluding the maxillary first molar, which tooth carries the greatest risk of sealer extrusion into the maxillary sinus?

Correct answer: D. Maxillary second premolar

• A. The lateral incisor apex relates to the nasal floor and the lateral fossa, not the maxillary sinus.
• B. The canine apex is the furthest from the sinus of the maxillary teeth and relates instead to the canine fossa.
• C. The first premolar apex is usually further from the sinus and its palatal root, when present, angles away.
• D. CORRECT. The floor of the maxillary sinus typically extends anteriorly to about the second premolar region and is at its lowest over the molars. Of the teeth listed, the second premolar apex sits closest to and most often in direct contact with the sinus floor, sometimes with no intervening bone at all.

Note: Ranked proximity to the sinus floor: second molar > first molar > third molar > second premolar > first premolar. The question excludes the first molar to force the premolar answer.