Histomorphometric Analysis of Periodontal Tissue Regeneration by the Use of High Density Polytetrafluoroethylen Membrane in Grade II Furcation Defects of Dogs

Statement of Problem: There are limited histomorphometric studies on biologic efficacy of high density tetrafluoroethylen (d-PTFE) membrane. To investigate the healing of surgically induced grade II furcation defects in dogs following the use of dense polytetrafluoroethylene as the barrier membrane and to compare the results with the contra lateral control teeth without the application of any membrane. Mandibular and maxillary 3rd premolar teeth of 18 young adult male mongrel dogs were used for the experiment. The furcation defects were created during the surgery. 5 weeks later, regenerative surgery was performed. The third premolar teeth were assigned randomly to control and test groups. In the test group, after a full thickness flap reflection, the d-PTFE membrane was placed over furcation defects. In the control group, no membrane was placed over the defect. 37 tissue blocks containing the teeth and surrounding hard and soft tissues were obtained three months post-regenerative surgery. The specimens were demineralized, serially sectioned, mounted and stained with Hematoxylin and Eosin staining technique. From each tissue block, 35-45 sections of 10 µm thickness within 60µm interval captured the entire surgically created defect. The histological images were transferred to computer and then the linear measurement ranges of the defects area, interadicular alveolar bone, epithelial attachment and coronal extension of the new cementum were done. Then, the volume and area of afore-mentioned parameters were calculated considering the thickness and interval of the sections. To compare the parameters between the control and test teeth, we calculated the amount of each one proportionally to the original amount of defects. The mean interradicular root surface areas of original defects covered with new cementum was 74.46% and 29.59% for the membrane and control defects, respectively (p < 0.0001). Corresponding values for epithelial attachment were 16.03% and 48.93% for the membrane and control defects, respectively (p < 0.005). The mean volume of the new bone formed in the inter-radicular defects was 61.80% and 35.93% for the membrane and control defects, respectively (p < 0.02). The present study provided a biological rationale for high density polytetrafluoroethylen (d-PTFE, n-PTFE) as a barrier membrane for enhancement of the bone and cementum regeneration in grade II furcation defects subjected to regeneration therapy.