Oral Surgery · single question
An infection involves the maxillary premolar #13 (maxillary left second premolar). Which anatomical space is most likely compromised?
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Correct answer: A. Infraorbital (canine) space
Tooth #13 (maxillary left second premolar) has roots that are typically shorter than the attachment of the buccinator muscle, so infection can spread to the BUCCAL SPACE. However, for maxillary canine and premolar infections, if the apex is above the muscle attachment, infection spreads to the INFRAORBITAL (CANINE) space. For the maxillary premolars specifically, buccal space is most commonly involved. Note: maxillary canine (#11) classically spreads to the canine/infraorbital space.
- A. Incorrect. Submandibular space infections arise from mandibular molars (especially #17, #18) — not maxillary premolars.
- B. Incorrect (partially correct). The buccal space can be involved for maxillary premolar infections when the apex is below buccinator attachment — but canine space is the more classic answer for the premolar/canine region.
- C. CORRECT. The canine/infraorbital space is the classic destination for infections from maxillary premolars and canines, particularly when the apex is superior to the buccinator attachment.
- D. CORRECT (same as C). The canine space and infraorbital space refer to the same anatomical region in this context.