The buccinator is the primary cheek muscle, keeping food between the teeth during chewing by compressing the cheek inward. Its fibres decussate at the modiolus — upper fibres to the lower lip orbicularis and lower fibres to the upper lip orbicularis. The parotid duct pierces the buccinator to enter the oral cavity opposite the upper second molar. Buccinator flaps are used for intraoral defect reconstruction.
| Origin | Outer surface of the alveolar process of the maxilla and mandible (opposite the molar teeth) and the pterygomandibular raphe |
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| Insertion | Modiolus (the fibromuscular node at the corner of the mouth) — fibres decussate: upper fibres to the lower lip and lower fibres to the upper lip |
| Nerve Supply | Buccal branch of the facial nerve (VII) — motor; sensory from the buccal branch of V3 |
| Blood Supply | Buccal artery (branch of the maxillary artery) |
| Actions | Compresses the cheek against the teeth — prevents food accumulating in the oral vestibule during chewing; Assists in blowing (as in trumpeting — the bugler's muscle); Facial expression — produces the cheek retraction of grinning |
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The buccal fat pad of Bichat lies superficial to the buccinator and is accessible through a small intraoral incision for facial contouring (fat reduction) or for obliterating dead space after jaw surgery. Buccinator myomucosal flaps pivoting on the buccal artery provide vascularised intraoral tissue for palatal fistula closure and tongue reconstruction.
The buccinator is palpable by pinching the cheek between the finger and thumb — its tone is assessed during blowing and chewing.
Buccinator weakness from facial nerve injury producing drooping of the oral commissure and food pocketing in the oral vestibule.
