Relations

• Its medial surface is covered by the mucous membrane of the mouth.^[3][2]
• Its lateral surface is separated from the ramus of the mandible by adipose tissue.^[2]
• Its posterior border gives attachment to the superior pharyngeal constrictor muscle.^[3]
• Its anterior border attaches to the posterior edge of the buccinator muscle.^[3]

The pterygomandibular raphe is the common meeting point of the superior pharyngeal constrictor muscle and the buccinator muscle. This common attachment makes the raphe a junction of the oral cavity, oropharynx, and nasopharynx.^[3]

The inferior alveolar nerve passes lateral to the raphe; the raphe is therefore a landmark for a nerve block of this nerve.^[2]

The general location of the raphe is indicated by the pterygomandibular fold.^[3]

Attachments

The pterygomandibular raphe gives attachment to the central portion of the buccinator muscle anteriorly, and to the superior pharyngeal constrictor muscle posteriorly.^[2]

Variation

In foetuses, the pterygomandibular raphe is always very prominent. However, in adults, it may become less distinctive. It is very large and distinctive, in around 36% adults. It is fairly small, and only an upper triangular portion visible, in around 36% of adults. It is not visible in around 28%, making the superior pharyngeal constrictor muscle and the buccinator muscle continuous. This may vary by ethnic group.^[4]