In vivo resistance of coronally induced bacterial ingress by an experimental glass ionomer cement root canal sealer

The resistance of an experimental sealer (KT-308) to bacterial ingress was assessed in six beagle dogs. In four mandibular premolars per dog, canals w ere prepared, filled with condensed gutta-percha and either KT-308 or Roth 801 cement (n = 24 roots), and the pulp chambers inoculated with plaque. Tw o additional premolars per dog were similarly root-filled, but not inoculat ed (n = 12 and 11, respectively). One incisor per dog was inoculated, but n ot root-filled (n = 6), Dogs were terminated after 6 months, and jaw blocks were retrieved and processed for light microscopic examination of the peri apical tissues. Inflammation about the inoculated roots was significantly l ower (p < 0.03) for KT-308 (17%) than Roth 801 cement (46%), Inflammation a bout the noninoculated roots did not differ significantly between KT-308 (8 %) and Roth 801 cement (36%). This study demonstrated a better functional e fficacy of KT-308 than of Roth 801 cement, and validated this in vivo model for assessment of root filling materials.