Influence of filling procedures and the partial removal of filling on the seal of root canals filled with gutta-percha and glass ionomer cement.

The purpose of the present study was to investigate the apical seal of root canals filled with Ketac Endo glass ionomer cement with a single point or multiple points and partial removal of fillings using drills with or without water cooling. Ninety-six single-root teeth were instrumented and filled with Ketac Endo and gutta-percha. The single point procedure was used in 48 teeth and the multiple point procedure was used in the other 48 teeth, without lateral condensation. After 72 hours, 16 teeth were randomly selected from each of the two groups and the fillings were partially removed with drills without cooling. The fillings from an additional 16 teeth were partially removed with water spray cooled drills. The fillings in the remaining teeth were not removed. All the teeth were partially protected with nail varnish and then dipped in Indian ink and finally cleared. The maximum linear leakage was measured under a binocular microscope with a micrometric eyepiece. There were no significant differences in leakage between any of the study groups, the root canals filled with the multiple point procedure had a seal similar to those filled with a single point. There was no diference between canals with fillings removed with or without water cooling and they did not have any more leakage than the root canals whose fillings had not been removed. Using Ketak Endo as a sealant, the multiple point procedure without condensation achieves sealing similar to the single point procedure. Partial removal of the fillings from these teeth, with or without water-cooling does not affect the seal.