Evaluation of a high-density polytetrafluoroethylene (n-PTFE) membrane as a barrier material to facilitate guided bone regeneration in the rat mandible.

The purpose of this investigation was to evaluate the use of high-density polytetrafluorethylene (n-PTFE) membranes to facilitate guided tissue regeneration (GTR) in the rat. The concept of guided tissue regeneration is based on the hypothesis that if the non-osteogenic connective tissue cells are mechanically blocked from entering a bone defect, selective re-population of the defect by osteoblasts will occur. Bilateral through-and-through defects of critical size were created in the mandibular angle of 12 rats. The experimental side was covered on both the medial and lateral aspects of the mandible with high-density n-PTFE membrane, with the opposite side serving as a control. Histological analysis revealed osteogenic tissue completely bridging the defect by two weeks. After six weeks of healing, osteogenic repair was observed at the margins of the defects, with islands of woven bone seen in the central areas. After 10 weeks of healing, complete ossification was observed on the n-PTFE-treated side. The control defects exhibited very little osseous regeneration, and rounding of the defect margins was observed after 10 weeks of healing. These results indicate that high-density n-PTFE can serve effectively as a guided tissue regeneration barrier in certain bone defects.