Maxillary Sinus Floor — MFDS Part 1 MCQ

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EasyAnatomy (Head & Neck)Maxillary Sinus FloorMFDS Part 1

Which bony structure forms the floor of the maxillary sinus?

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Correct answer: C — Alveolar process of the maxilla

The correct answer is C: the alveolar process of the maxilla forms the floor of the maxillary sinus. This explains the close anatomical relationship between the sinus and the roots of the maxillary premolars and molars; in some individuals, only a very thin layer separates the roots from the sinus lining. The orbital surface of the maxilla forms the roof of the sinus and part of the orbital floor. The palatine bone contributes to the posterior nasal and palatal region rather than forming the sinus floor. The zygomatic bone is related to the superolateral maxilla, while the inferior nasal concha lies on the lateral wall of the nasal cavity.

Reference: Ordinola-Zapata R, Azevedo B, Tataryn RW, Versiani MA. Maxillary Dental Anatomy and Physiology: Endodontic and Periodontal. Otolaryngology Clinics of North America. 2024;57(6):927–939. https://pubmed.ncbi.nlm.nih.gov/39214739/