Objectives: To define (1) at-risk structures during the orthodromic temporalis tendon transfer and (2) achievable tendon length without temporal releasing incisions or perioral lengthening materials.
Methods: Ten fresh cadavers provided 20 hemifaces for dissection. Measurements and photographic documentation were used to examine the parotid duct, masseteric artery, inferior alveolar nerve, internal maxillary artery, and mobilized tendon relative to adjacent landmarks.
Results: The parotid duct was found in a reproducible region posterior to the melolabial crease and inferior to a parotid duct reference line. The masseteric artery was found posterior to the posterior-most attachment of the tendon at its exit from the sigmoid notch (mean, 14.5 mm). The inferior alveolar nerve was found posterior to the anterior edge of the ascending ramus (mean, 18.3 mm). The internal maxillary artery coursed superiorly from posterior to anterior along the medial mandible near the coronoidectomy site. The tendon reached beyond the melolabial crease in 17 of 20 hemifaces (85%).
Conclusions: The parotid duct reference line and the melolabial crease allow estimation of the parotid duct location. Anatomical relationships between the tendon, parotid duct, neurovasculature, and anatomical landmarks underscore the importance of deliberate soft-tissue retraction and subperiostial elevation to minimize injury. The tendon alone usually provides adequate length for orthodromic suspension.