Dimensions of incisive fossae on dry skulls and radiographs.
The dimensions of the incisive fossae of 960 Negroid skulls were measured and the frequency of nasopalatine duct cysts in this material was determined. A random sample of 200 of the above skulls was radiographed under standardized conditions and the radiographic dimensions of the incisive fossae were compared statistically with their actual dimensions. Incisive fossa widths of greater than 6 mm were found in 148 specimens (15.3%), and anteroposterior dimensions of greater than 7 mm were found in 799 specimens (82.4%). Thirteen cysts were found. Radiographic measurements of incisive fossae were significantly different from those made on the skulls. Mean dimensions of the fossae in this sample were greater than those previously reported and there was a higher frequency of nasopalatine duct cysts.