Abstract

From the Department of Operative Dentistry (Head: Professor G. WESTIN) and the Department of Dental Histopathology (Head: Associate Professor G. BERGMAN), the Royal School of Dentistry, Stockholm. Sweden. I)ecnlcificntion of tlic Teeth: / A New Method Using Supersonic Radiation. (Preliminary Beport.) BY TORE ARWILL. Review. For the decalcification of the teeth a number of organic and inorganic acids of various concentrations have been used. In many of the methods the action has been too slow, however, with consequent poor response to stains. By accelerating the decal- cification this disadvantage could be overcome, while at the same time the duration of the experiment would be shorter. Among those who have been occupied with the problems of decalcification mention may be made of LINDAHL, who in 1937 used carbon dioxide in an attempt to decalcify smaller specimens containing calcium carbonate, the gas being conducted through an aqueous suspension under a pressure of an atmosphere or more. In 1944 PORSHUFVUD used acids at pressures of 3-4 atm. which, he claimed, would prevent the destruction of the organic stroma of the enamel. AASGAARD (1943) stated that calcium and phos- phorus were liberated by electrolysis, especially when the tooth served as the positive electrode,