Anatomy and Variations of the Retromolar Fossa

  • Puhan HeEmail author
  • Mindy K. Truong
  • Shogo Kikuta


The retromolar region is a triangular area bounded by temporal crest on the medial side, anterior border of ramus on the lateral side, and the posterior portion of the third molar area. The deeper fibers of the temporalis muscle attach to the upper two-thirds of the medial boundary of the retromolar fossa. The superficial fibers of the temporalis muscle attach to the upper one-third of the lateral boundary of the retromolar triangle. The buccal nerve and artery cross the middle portion of the medial border, while the lingual nerve crosses the inferior portion. The retromolar foramen also consists of clinically relevant vessels and nerves. The posterior portion of the third molar attaches to the pterygomandibular raphe, where the buccinator and superior pharyngeal constrictor muscle attach anteriorly and posteriorly. It is implicated clinically in procedures such as third molar extractions, periodontal distal wedge procedures, and sagittal split osteotomy. Furthermore, the retromolar trigone marks an aggressive type of oral cancer.


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© Springer Nature Switzerland AG 2019

Authors and Affiliations

  1. 1.Harvard School of Dental MedicineBostonUSA
  2. 2.Kurume University School of MedicineKurumeJapan

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