Unlike in some other oryzomyines, the buccinator-masticatory foramen and the foramen ovale accessorium, two foramina (openings) in the skull, are not separated by an alisphenoid strut.
In the head and neck, potential spaces are primarily defined by the complex attachment of muscles, especially mylohyoid, buccinator, masseter, medial pterygoid, superior constrictor and orbicularis oris.
The duct pierces the buccinator muscle, then opening up into the oral cavity on the inner surface of the cheek, usually opposite the maxillary second molar.
To the outer lip of the superior border, on either side, the buccinator is attached as far forward as the first molar tooth.
The buccal space is superficial to the buccinator muscle and deep to the platysma muscle and the skin.
The lower lip is supported by the buccinator and chin muscles and rests on the lower teeth, making contact with the reed.
The buccinator acts as a valve that prevents inflation of the duct during blowing.
As time progresses, it spreads to the whole lid, then to the orbicularis oris muscle around the lips, and buccinator muscle in the cheekbone area.
