In vivo microleakage evaluation of two root filling materials in teeth without a coronal seal

Two carrier-based materials were compared to assess their resistance to coronal microleakage in a dog model when no coronal seal was present. Histologic evidence of inflammation and infection were the outcome parameters used. Experimental teeth were filled with carrier-based ResilonRTM (Epiphany RTM, n=25) or with carrier-based gutta-percha (Thermafil RTM, n=25) and were left exposed for four months. One control group received a coronal seal over EpiphanyRTM or Thermafil RTM root fillings. A second control group was instrumented and left empty. There was a higher frequency of inflamed teeth in the Thermafil RTM group (29%) than in the EpiphanyRTM group (9%). 2 of 22 EpiphanyRTM filled teeth (9%) showed evidence of tubular infection, whereas 16 of 23 ThermafilRTM filled teeth (70%) were infected. The difference in infection rates between Epiphany RTM and ThermafilRTM was statistically significant (p<0.001).