Supraarticular, supramastoid and suprameatal crests on the outer surface of the temporal bone and the relation between them.

Supraarticular, supramastoid and suprameatal crests on the outer surface of the squamous part of the temporal bone are of clinical importance as they are accepted as landmarks for some surgical approaches relating to the temporomandibular joint, the middle cranial fossa and mastoid air cells, respectively. Because of the surgical importance of the crests, their incidence and the relations between them were studied on a total of 442 (250 male, 192 female) dry skulls. In addition, three-dimensional (3D) surface renderings of the squamous part of the temporal bone were created from routine axial computed tomographic (CT) images in four cadaver specimens to demonstrate the surface anatomy. Suprameatal crests were observed commonly as a trace type on the male dry skulls (51.2%), though no such crest was seen on most of the female skulls (54.4%). Supramastoid crests were commonly observed as a small crest on male dry skulls (46.6%), but as a trace type on female dry skulls (52.05%). Supraarticular crests were commonly seen as a trace type on both male (58.6%) and female (70.6%) dry skulls. In the light of the above data, it can be concluded that the crests on the male dry skulls were stronger than those on the female skulls. The angles between the crests were also examined. It was observed that the angle between the supraarticular and supramastoid crests was larger in male dry skulls compared with the female dry skulls. On the other hand, no gender difference was observed when the angle between the suprameatal and supraarticular crests was examined.