Piezoelectric shock wave lithotripsy of salivary gland stones: an in vitro feasibility study

The feasibility of fragmentation of salivary stones by a new extracorporeal piezoelectric lithotripter was investigated. A total of 40 salivary stones were submitted to piezoelectric shock wave treatment. The diameter, weight, and volume of all the stones were determined prior to shock wave administration. After shock wave administration the chemical composition of the stones was investigated by X-ray diffractometry. Fragmentation was achieved in 35 out of the 40 (87.5%) stones. Twenty-five of the 40 (62.5%) stones were disintegrated "therapeutically adequate" (residual fragments less than 1.5 mm). A statistically significant correlation was not observed between the number of discharges required for disintegration and the diameter, weight, volume, or the chemical composition of the stones.