Sicca syndrome and silicoproteinosis in a dental technician

Secondary sicca syndrome has been described in silicotic and exposed nonpneumoconiotic individuals. Systemic autoimmune pathogenic mechanisms have been thought to be responsible. Salivary gland mineral deposition has not so far been implicated. We describe the case of a dental technician who sand-blasted dental prostheses and developed silicoproteinosis and sicca syndrome. Immunological studies were negative. Scanning electron microscopy study and energy-dispersive X-ray analysis were carried out in the patient's lung and salivary gland and in two salivary glands from nonexposed individuals diagnosed with sicca syndrome. High peaks of silicon and aluminium were detected in the patient's lung and salivary gland. Silicon/sulphur and aluminium/sulphur ratios were higher in the patient's glands (0.612 and 0.402, respectively) than in the two control salivary glands (0.193 and 0 and 0.127 and 0, respectively). We suggest that, in this case, sicca syndrome could have been caused by inorganic deposition.