Premium
Effect of thermal placement techniques on some physical properties of gutta‐percha
Author(s) -
COHEN B. D.,
COMBE E. C.,
LILLEY J. D.
Publication year - 1992
Publication title -
international endodontic journal
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.988
H-Index - 119
eISSN - 1365-2591
pISSN - 0143-2885
DOI - 10.1111/j.1365-2591.1992.tb00759.x
Subject(s) - gutta percha , materials science , softening , softening point , thermal expansion , composite material , thermomechanical analysis , root canal , dentistry , medicine
Summary Some clinical techniques for the placement of gutta‐percha root fillings involve the application of heat. This study was undertaken to assess the effects of intracanal heating techniques on the following properties of gutta‐percha: coefficient of thermal expansion, softening temperature, phase transition temperature and organic content. Samples from each of four products were prepared by three different methods. The materials were studied by thermomechanical analysis, simultaneous thermogravmetry and differential thermal analysis, and by measurement of weight loss on ashing. It was shown that the techniques of gutta‐percha placement involving heating in the root canal caused reversible physical changes in the materials without any apparent change in chemical composition. The average coefficient of thermal expansion was 137 × 10 −6 /°C, the softening temperature was 55.5°C, there were two characteristic phase changes, and the organic content was 25%.