Tissue reactions to endodontic materials implanted in the mandibles of guinea pigs

Teflon, Intermediate Restorative Material, and Prisma VLC Dycal were implanted in the mandibles of 16 guinea pigs. After experimental periods of 4 and 12 weeks, the animals were killed and tissue sections were prepared. No severe inflammatory response was noted in any of the groups except for a persistence of moderate inflammation in the poorly condensed Teflon group. Bone apposition occurred in the Prisma VLC Dycal group; none-to-mild inflammation and a thin fibrous capsule characterized the IRM group; and the Teflon group had a thick fibrous encapsulation except for samples where the Teflon material appeared to be poorly condensed and dispersed into the bony tissue. In areas where the teflon was loosely condensed, chronic inflammation and active phagocytosis were seen along the surface of the material.