The present study was to evaluate the healing patterns of guided tissue regeneration(GTR) using resorbable Vicry??(polyglactin 910) mesh and nonresorbable expanded polytetrafluoroethylene(ePTFE) membrane with or without bone grafting using autogeneous bone and demineralized freeze-dried bone allograft(DFDBA) in the grade Ⅱ furcation defects.
Mucoperiosteal flaps were reflected buccally in the mandibular 2nd, 3rd and 4th premolar areas and furcation defects were created surgically by removing 5 × 6mm alveolar bone in 4 dogs. Root surfaces were thoroughly debrided of periodontal ligament and cementum, and notches were placed on root sruface at the most apical bone level.
In the right and left mandibular quadrant, each tooth was received Vicryl?? mesh(ACE Surgical Supply Co., USA) only, Vicryl?? mesh with DFDBA, Vicryl?? mesh with autogeneous bone grafts, ePTFE membrane(Gore-tex?? membrane, W.L. Gore & Associates Inc., USA) only, ePTFE membrane with DFDBA or ePTFE membrane with autogeneous bone grafts.
For the fluorescent microscopic examination, fluorescent agents were injected at 2, 4 and 8 weeks after surgery. Four weeks after surgery, 2 dogs were sacrificed and ePTFE membranes were removed from remaining 2 dogs, which were sacrificed at 12 weeks after surgery. Undecalcified tissues were embedded in cethylmethacrylate and 10㎛ thick sections were cut in a buccolingual direction. These sections were stained with hematoxylin-eosin stain and Masson’s trichrome stain, and evaluated by descriptive histology and linear measurements.
The results were as follows :
1) Vicryl?? mesh group showed less connective tissue attachment than ePTFE membrane group.
2) The combination of GTR using Vicryl?? mesh and osseous grafts resulted in new attachment and new bone formation more than GTR using Vicryl?? mesh only.
3) GTR using ePTFE membrane, with or without osseous grafts, enhanced periodontal regeneration.
4) Root resorption and dentoalveolar ankylosis were observed in the areas treated with the combination of GTR and DFDBA.
It was suggested that the effect of adjunctive bone grafting in GTR procedure depends on the materials and the physical properties of barrier membranes. Vicryl?? mesh performed a barrier function and the use of adjunctive bone grafting may enhance the periodontal regeneration.
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