MICROLEAKAGE ALONG APICAL ROOT FILLINGS AND CEMENTED POSTS

Statement of problem. Coronal leakage of endodontically treated teeth has been found to result in a high failure rate. Purpose. This study t ested leakage along apical root fillings remaining after post space pr eparation and cemented posts in root canals. Material and methods. A t otal of 120 human roots were used in the study and divided into six gr oups, 20 roots for each group. By using a modified fluid transport mod el, leakage (in mu L/hr) along ParaPost dowels that were cemented in t he coronal 7 mm of root canals with Fuji Duet, Ketac Gem, Panavia EX, or zinc phosphate cements was compared with that along the coronal 7 m m of conventional root canal fillings. Leakage along the apical 4 mm o f root filling remaining after post space preparation was compared wit h that along the 11 mm root filing before post space preparation. Resu lts, More leakage was recorded along the apical 4 mm of root filling t han along the 11 mm of original root filling (p = 0.0325). ParaPost do wels cemented with any test cement did not produce more leakage than t he 7 mm coronal root filling (p = 0.2145). Conclusions. The apical 4 m m of root canal filling remaining after post space preparation leaks s tatistically significantly more than the original full-length root can al filling. The leakage created by removal of the coronal part of root canal filling during post space preparation may be compensated by the cemented posts.