Maxillary sinus relationship to posterior teeth — ORE Part 1 MCQ

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ModerateApplied Dental SciencesMaxillary sinus relationship to posterior teethORE Part 1

A patient develops sinus symptoms after extraction of an upper first molar. A pre-operative periapical radiograph showed the root apices close to the sinus floor, and the palatal root was long and divergent. Which anatomical relationship best explains this complication?

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Correct answer: C — Maxillary molar roots may closely relate to the sinus floor

Explanation lettering: D = shown as C · E = shown as D · C = shown as E

D is correct. The roots of maxillary posterior teeth, including first molars, can lie immediately beneath, abut, or project towards the floor of the maxillary sinus. Therefore, extraction of a molar with a long divergent palatal root close to the sinus may disrupt the sinus lining and produce an oro-antral communication, causing sinonasal symptoms. Imaging studies show that maxillary molar apices are commonly intimately related to the sinus floor, and the palatal root of an upper first molar may protrude into the sinus. A, B and C incorrectly associate mandibular or anterior anatomical structures with the maxillary antrum. E is incorrect because Wharton's duct is the submandibular duct and has no relationship to upper molars or sinus drainage.

Reference: Whyte A, Boeddinghaus R. The maxillary sinus: physiology, development and imaging anatomy. Dentomaxillofacial Radiology, 2019. https://pubmed.ncbi.nlm.nih.gov/31386556/