Scanning electron microscopic and X-ray microdiffractometeric studies on sialolith-crystals in human submandibular glands.

The crystalline structures of 18 submandibular gland calculi were studied by radiomicrography , scanning electron microscope, and X-ray microdiffractometeric techniques. The following observations were made by SEM: Granular or globular structure was seen on the surface of all cases and pyramidal crystal in one case. In the inside, all showed lamellar pattern with amorphous nucleus in the center, and granular, plate-like and rhombohedral structures were also observed. X-ray microdiffractometeric analyses: Apatite was frequently observed in both outside and inside of the calculi. Whitlockite was next frequently detected and was seen more often in the inside. Brushite and weddellite were noted in the outside of calculi in one case each. Thus, it is suggested that brushite and weddellite were present in the front portion of calculus formation and then transformed into the more stable form e.g. apatite.