Unilateral duplication of parotid duct – a rare cadaveric case report

Abstract

The parotid gland is drained by the parotid duct which normally measures 50 mm in length and 3 mm in width. The parotid duct emerges at the anterior border of the gland and runs horizontally across the masseter muscle to pierce the buccinator and open into the vestibule of the mouth. The occurrence of double parotid duct is 7% and there are only very few literature references. The parotid gland develops as an epithelial bud arising from the oral ectoderm and invaginating into the underlying mesenchyme. The proximal part canalises to form the duct and the distal end differentiates to form the acini. An early division of the parotid duct with acini from both ducts intermingling with each other results in the formation of double parotid duct. The cytodifferentiation and morphogenesis of parotid gland are influenced by cell specific gene expression and cell-matrix interactions that produce collagen responsible for branching and hyaluronidase responsible for acini formation. The awareness of presence of a double parotid duct is significant in ductal endoscopic procedures and in performing surgery in the parotid region.