[Radiocrystallographic study of 46 salivary calculi. Physiopathogenic hypotheses (author's transl)]

The radiocrystallographic study of 46 salivary calculi using the Debye and Scherrer powder methods showed that such stones, whether submaxillary, parotid or "accessory" consist essentially of hydroxyapatite with the frequent presence of tricalcium and octocalcium phosphates, Whitlockite and rarely Brushite and Calcite. In order for a stone to form, the following conditions would seem to be necessary; transient supersaturation of the saliva in Ca++ and PO4--, a pH greater than normal, intracellular precepitation of amorphous tricalcium phosphate which is transformed into crystalline hydroxyapatite and, then, the fixation of crystals on a "matrix" such as desquamated cells, fibrils and collagens.