Sialolithiasis is a process of unknown aetiology in which calculus concretions form in the salivary gland ducts and tissue. It may occur at any age but it is most common in middle-aged adults. A case is presented of the occurrence of double giant sialoliths in the left Wharton's duct in a 16-year-old boy. The clinical symptoms and signs were somewhat atypical and included acute suppurative cellulitis in the floor of the mouth plus localized periodontitis involving 36. Under a local anaesthetic the stones were surgically extracted and healing was uneventful. Proper interpretation of symptoms and thoughtful investigation for localization of salivary stones is emphasized.