Shock wave lithotripsy of salivary gland stones has become more and more efficient in the treatment of sialolithiasis during the last years. We use two different methods in our hospital: Extracorporeal shock wave lithotripsy (ESWL) and endoscopically intracorporeal lithotripsy (EISL). The results of both therapies are compatible; 60-70% could be successfully treated. The indication is different due to the localisation of the salivary gland stone. Stones that are located in the glandula or very proximal in the duct should be fragmented by extracorporeal lithotripsy. Stones located in the duct and multiple intraductal stones should be treated by the intracorporeal method. Clinical experiments showed that some salivary stones do not fragment easily. The reason is still unknown. We examined the ability of fragmentation in relation to the physicochemical analysis of the stone. The stones were examined by infrared spectroscopy. This study revealed that pure carbonate apatite stones are more difficult to destroy than stones containing some protein.