It is pointed out that minor salivary gland calculi are more common than previously supposed in the English language literature. But in Japan, reports of them are still rare and as far as we know only sixteen cases have been reported.
This report contributes three additional cases of sialolithiasis in the minor salivary gland located in the upper lip of elderly persons. They were solitary, firm, freely movable, small masses. Histopathologically, all the calculi revealed similar findings that contained homogenous non mineralized organic matrix. Chronically inflamated granulation tissue surrounded the calculus in 2 cases and the dilated duct surrounded the calculus in 1 case. Chronic lobular inflamation and diffuse lobular fibrosis were common findings.
The authors suggested that clinicians and pathologists tend to fail to diagnose the calculi of minor salivary gland if the calculus was small and nonmineralized, and soft tissue inflamation was prominent.
