title: A comparative sealability study of different retrofilling materials.
abstract: The purpose of the study was to compare the sealing properties of Cavit and zinc polycarboxylate cement with silver amalgam when used as retrofilling materials of root canals. The retrofilling materials were placed at the apices of dogs' teeth and were left there for a 6-month period, after which time the teeth were extracted and the marginal leakage was evaluated by C14-labeled urea. A second part of the study included an in vitro placement of the retrofillings. Previously extracted teeth were used and the same retrofilling materials were placed. They were left to set for 2 days in physiologic saline solution. Then the same evaluation for leakage was used. The purpose of the second part was to compare and evaluate the effect of aging on sealability. Under the conditions of this study, amalgam afforded a better seal in the 6-month group than polycarboxylate cement or Cavit. Both Cavit and polycarboxylate cement showed more leakage in the 6-month group. The deterioration of the seal afforded by Cavit in the 6-month group was statistically significant. The seal of amalgam was the only one which was improved by time.
mesh_terms: D000180:Acrylic Resins; D000268:Adhesiveness; D000818:Animals; D003723:Dental Amalgam; D004285:Dogs; D005069:Evaluation Studies as Topic; D011076:Polycarboxylate Cement; D012184:Retrograde Obturation; D012387:Root Canal Filling Materials; D013499:Surface Properties; D015032:Zinc
chemical_list: D000180:Acrylic Resins; D011076:Polycarboxylate Cement; D012387:Root Canal Filling Materials; D003723:Dental Amalgam; D015032:Zinc