Infra-red spectroscopic study for decalcification in the dentine

Summary A study was made of spectra of decalcified human dentine being treated with five decalcifying agents to investigate the differences of infrared spectra of decalcified dentine.Solutions of 20% 4-Na-EDTA, 5% HNO₃, 10% sulfosalicylic acid, 10% CCl₃COOH and 10% lithium lactate were used as decalcifying agents. Infrared absorption spectra between 1800 and 650 cm^–1 were obtained for the investigation of the absorption strength at 1033,1095; 1412–1414 to 1450–1455; 875–870; 1649 and 1550 cm^–1 before and after decalcification.The specimens following decalcification with EDTA and HNO₃ showed almost no influences to the absorption strength at 1649 and 1550 cm^–1 of amides. Such absorption spectra were relatively slight in CCl₃COOH and sulfosalicylic acid. The absorption strength at 1033 and 1095 cm^–1 bands of PO₄^–––may indicate a standard of decalcification. Quick and complete decalcification of dentine was performed by HNO₃, CCl₃COOH and sulfosalicylic acid but slower and more incomplete decalcification resulted with EDTA and lithium lactate.