The coronoid process as a cause of mandibular hypomobility--case reports.

In an attempt to draw the clinician's attention to the coronoid process site while evaluating the aetiology of the restriction of mandibular opening, four cases are illustrated. These cases represent a diversity of causes hampering the free rotational movement of the coronoid process in space during jaw function. Case 1 is an example of unilateral hyperplastic coronoid process and osteochondroma; case 2 shows unusually shaped short and divergent coronoid processes combined with a bucally displaced maxillary third molar on one side; cases 3 and 4 represent an anatomical variation of an extremely narrow vestibular space due to the close proximity of the medial aspect of the coronoid process to the distal molar. It is suggested that each clinical examination include the width of the buccal vestibular space while performing mandibular movements.