Crystalline structure of salivary calculi. A microradiographic and microdiffractometric study

The crystalline substances localized in different areas of salivary calculi were identified by using microradiographic and X-ray microdiffractometric techniques. All 19 calculi analyzed had a general pattern of apatite which was recognizable both in the center and at varying distances from the core. In addition to apatite patterns, six of the calculi gave a diffraction pattern of whitlockite, which in all but one case was located in the central part of the calculi. The influence of various factors on the distribution of the crystalline substances of apatite and whitlockite within the calculi is discussed.