INTRODUCTION The importance of the mouth to the otolaryngologist is self-evident. It is the portal of entry for visual examination of the oropharynx, larynx and the opening of the Eustachian tube in the nasopharynx. It is also the portal of entry for many of the surgical procedures undertaken in these regions. Malformations in the mouth, such as cleft palate, may have important consequences for the healthy functioning of the system. Infection or tumours from the mouth may spread to involve the ear, nose and throat. As an example, infection from maxillary teeth may give referred pain to the nasal region, while infection from mandibular teeth may spread to the neck and result in severe (and sometimes fatal) respiratory embarrassment. Due to its close physical (and also evolutionary) relationship to the ear, clinical conditions affecting the jaw joint (temporomandibular joint) may need to be differentiated from those directly involving the ear.