Dimensional accuracy of castable apatite ceramic crowns: the influence of heat treatment on dimensional changes and distortion of crowns.
Castable apatite ceramic crowns are subjected to heat treatment during crystallizing and during coloring after casting. The dimensional accuracy of the heat-treated crowns was investigated with respect to its influence on dimensional changes in castable apatite ceramic crowns and on distortion of the interior of the crowns, using two investment techniques and a three-coordinate measuring machine. Dimensional changes were not influenced by the number of coloring firings. Distortion of the interior of crowns was slightly outward at the gingival plane. Shrinkage because of crystallizing was approximately 20 microns and the shrinkage of the gingival plane was equal to that of the occlusal plane.
Ishida
H
H
Department of Prosthetic Dentistry, Hiroshima University School of Dentistry, Japan.
Nahara
Y
Y
Hamada
T
T
D001031:Apatites / Q000737:chemistry*; D002516:Ceramics / Q000737:chemistry*; D003116:Color; D003442:Crowns; D003460:Crystallization; D003734:Dental Casting Investment / Q000737:chemistry*; D003735:Dental Casting Technique / Q000295:instrumentation; D003779:Denture Design / Q000295:instrumentation; D006358:Hot Temperature; D008422:Materials Testing; D013499:Surface Properties
D001031:Apatites; D003734:Dental Casting Investment