AN IN-VITRO STUDY OF APICAL AND CORONAL MICROLEAKAGE OF LATERALLY CONDENSED GUTTA-PERCHA WITH KETAC-ENDO AND AH-26

The purpose of this in vitro study was to compare both apical and coro nal dye penetration when Ketac-Endo and AH-26 sealers were used with l aterally condensed gutta percha. Crowns were removed from 28 teeth and the root canals were biomechanically prepared. The teeth were divided into two groups of 12 teeth each and a control group of 4 teeth. Root canals in the two experimental groups were filled with laterally cond ensed gutta percha and either Ketac-Endo or AH-26 sealer. The Ketac-En do group had the coronal 3 mm of gutta percha and sealer removed and t he resultant cavity was filled with Ketac-Endo alone. After the sealer s had set, the root surfaces were coated with nail varnish except at t he apex and at the coronal end. Positive controls had no root fillings and were coated with nail varnish in the same manner while the negati ve controls were sealed apically and coronally with Cavit prior to sea ling the entire external root surface with nail varnish. Specimens wer e placed in 2% methylene blue dye in a vacuum of 660 mm of mercury for five minutes and then left immersed for a further two days. The roots were vertically sectioned to determine the following mean levels of d ye penetration: Ketac-Endo, 1.08 mm apically and 6.29 mm coronally; AH -26, 0.75 mm apically and 6.67 mm coronally. Positive controls had tot al leakage and negative controls had no leakage. This study demonstrat ed that the apical and coronal seals obtained with Ketac-Endo and AH-2 6 were not significantly different although the epical seal obtained w ith each material was significantly better than the corresponding coro nal seal.