Abstract: This paper presents 16 cases of calvaria with depression and thinning in parietal bones among 1480 adult skulls. The items investigated are the form and depth of the depression as well as the sex, age and form of skulls. Besides, roentgenologic and histologic methods were also used in this study.
All depressions were found in the skulls of aged, and most of them occurred bilaterally and appeared as the thinning of outer lamina and dipl?e of calvarium without involvement of surrounding tissues.
ln the lateral radiogram, the depression showed as a wide-band and low-density opacity.The bone section in this region demonstrated increment of incompletely, closed osteons and also the occulusion of lacunae which probably led to bone atrophy.

Key words: Parietal bone; Age changes