The Normative Topographic Position of the Wharton's Duct Orifice in Adults

Purpose: We aimed to establish a normative database for the topography of Wharton's duct orifices and to indicate the localization and distances of the orifices against other oral structures. Methods: The prospective study involved 3,000 healthy adults. We measured the cranial index, the distances between the mandible gonions and the orifices and between each orifice and the lingual frenulum, the position of the orifices against each other, and against the base of the tongue and the mandibular alveolar ridge. The segments of the cohort were classified by sex and the headform (dolichocephalic, brachycephalic, and mesocephalic). Results: The distance between the orifices varied from 0 mm in the frenulum-attached cases to11.0 ± 2.3 mm in cases of the male brachycephalic skull. The correlation with sex was found for the localization of the frenulum-related orifices (r = 0.64 for females). The orifices were attached to the frenulum (5.9%), were frenulum-related (16.2%), and frenulum-independent (77.9%). The sagittal asymmetry of the orifices was noted in 11.8%, and in 2.1%, the lateral asymmetry was detected. Conclusion: In most of the cases, the Wharton's duct orifices are symmetrical frenulum-independent openings that are usually located in the middle part of the floor of the mouth or close to the mandibular alveolar ridge. The distance between the orifices varies according to sex and the type of the skull. The precise position of the duct orifices must be established prior to sialoendoscopy of the submandibular glands, a botulinum toxin injection around the mandible, tongue traction maneuvers, frenotomy, and other oral surgeries.