<prompt> Parotid duct opens into:First mandibular molarFirst maxillary pre-molarSecond mandibular molarSecond maxillary molar  <response>: Ans. D Second maxillary molarRef: Grays Anatomy 41st ed. P 411, 505Parotid DuctStensen Duct It is a 5 cm long duct of parotid gland that originates from anterior border of upper part of parotid gland by the confluence of two main tributaries. Course: It then passes horizontally across masseter, midway between angle of mouth and zygomatic arch. Down the course it also crosses through buccal fat and buccinators muscle opposite the crown of upper third molar tooth. It then opens on a small papilla opposite the second upper molar crown. 