A COMPARISON OF TISSUE-REACTIONS TO KETAC-FIL AND AMALGAM

The objective of this study was to compare the bone tissue reactions o f Ketac-Fil to the most commonly used retrograde filling material, ama lgam, in a rat model. Forty-eight Harlan rats were divided into three groups: amalgam, Ketac-Fil, and controls. Following anesthesia, the ri ght lower incisor was extracted from each animal. A 3-mm long x 1-mm d iameter polyethylene tube filled with amalgam or Ketac-Fil was implant ed in the extraction site. The animals were killed at 14, 42, and 90 d ays; and the mandibles were dissected en block and processed histologi cally. The inflammatory reaction was assessed by the number of plasma cells, lymphocytes, polymorphonuclear neutrophils, giant cells, and os teoclasts within 100 mu m of the implant. Bone formation was determine d as either present or absent in the same area. There was no statistic ally significant bone apposition within 100 mu m of the Ketac material , and there was a statistically significant increase in inflammation i n the amalgam group. This study indicates that both Ketac-Fil and amal gam are relatively biocompatible, and provides support for clinical us age tests of Ketac-Fil as a retrograde filling material.