Titanium-reinforced Expanded Polytetrafluoroethylene Membrane Research Articles

The effect of micro-macroporous biphasic calcium phosphate incorporated with polyphosphate on exophytic bone regeneration

Purpose: In this study, the effect of micro-macroporous biphasic calcium phosphate(MBCP) incorporated with inorganic poly- phosphate for bone regeneration in the calvaria of rabbit was evaluated. Materials and Methods: The procedure of guided bone regeneration was performed with titanium reinforced expanded poly- tetrafluoroethylene(TR-ePTFE) membrane. Four animal groups were compared : 1) TR-ePTFE membrane for negative control group, 2) TR-ePTFE membrane filled with MBCP for positive control group, 3) TR-ePTFE membrane filled with MBCP soaked in 4% inorganic polyphosphate for experimental group I, and 4) TR-ePTFE membrane filled with MBCP soaked in 8% inorganic polyphosphate for experimental group II. Results: 1. Negative control group showed the highest new bone formation at 16 weeks. 2. Positive control group showed the smallest new bone formation compared to other groups. 3. 8% inorganic polyphosphate induced more volume of bone formation, otherwise experimental group II did not show significant difference compared to negative control group. Conclusion: These results suggest that inorganic polyphosphate has a promoting effect on bone regeneration, possibly by en- hancing osteoconductivity of the carrier and by increasing osteoinductivity of the defected alveolar bone tissue. (J Korean Acad Periodontol 2008;38:179-190)

Titanium-Reinforced Polytetrafluoroethylene Membrane Combined with Inorganic Polyphosphate Induces Exophytic Bone Formation in Rabbit Calvaria

The purpose of this study was to examine if the application of titanium-reinforced expanded polytetrafluoroethylene(TR-ePTFE) membrane combined with bovine bone mineral(BBM) soaked in inorganic polyphosphate promotes exophytic bone formation in rabbit calvaria. For this purpose, a total of 8 rabbits were used, and rectangular decorticated calvaria sites were created using a round carbide bur. In the control group, rectangular parallelepiped-shaped TR-ePTFE membranes (RPTPMs) were filled with BBM soaked in saline and placed on the decorticated sites and fixed with metal pins. In the experimental groups, RPTPMs were filled with BBM soaked in 4%, 8% and 16% inorganic polyphosphate prior to fixing with metal pins. Animals were sacrificed at 4 and 8 weeks after surgery, and new bone formation was assessed by histomorphometric as well as statistical analysis. The results indicated that at 8 weeks, all the experimental groups demonstrated exophytic bone formation. At 8 weeks, the 8% polyphosphate group revealed the most new bone formation (p<0.05). On the basis of these findings, we conclude that inorganic polyphosphate has a promoting effect on bone regeneration, possibly by enhancing osteoinductivity of the decorticated wound area and osteoconductivity of the carrier material, but not much as we expected.

Osseous reconstruction using a membrane barrier following marginal mandibulectomy: an animal pilot study.

Invasive and malignant tumors of the oral soft tissues adjacent to the mandible are often treated with partial resection of the osseous structure adjacent to the lesion (marginal mandibulectomy). Autogenous bone graft and composite bone grafts are being used to fill the osseous defects with various degrees of success. The aim of the present study was to explore the utilization of membrane barriers and the principle of guided bone regeneration to negotiate these defects. Following the removal of P1, P2, and P3, experimental bilateral marginal mandibulectomy defects were created in 4 adult dogs. The bone segments (measuring 25 mm x 15 mm) were then removed. Each side was then randomly selected for either experimental (titanium-reinforced expanded polytetrafluoroethylene membrane, [ePTFE-TR]) or control (repositioning flaps) treatment. Postoperatively, the animals were put on soft diet, antibiotics, and analgesics. Sutures were removed under light sedation after 4 weeks, and the area was left to heal and mature for 4 to 6 months (mean 5.3 months). The animals were then sacrificed, and block sections of the mandible were obtained for macroscopic and histological evaluation. The size of the residual defect (the vertical distance between the most apical depression in the ridge and the horizontal line connecting the free gingival margins of the proximal teeth) in the experimental sites (6.10 +/- 1.00 mm) was much smaller compared to the controls (10.65 +/- 0.82 mm), which was statistically significant (P = 0.0127). Histomorphometric measurements of new bone formation (NBF) revealed a similar pattern: for the experimental sites, NBF was 8.08 +/- 0.85 mm compared to 4.99 +/- 0.61 mm in the controls. These differences were also statistically significant (P = 0.0257). A regenerative approach to large mandibular osseous defects has been described. If this new treatment modality is further substantiated in other independent studies, it might prove a useful tool in restoring the lost osseous structure associated with marginal mandibulectomy procedures.

Bone augmentation and biopsy: clinical report

A mixture of demineralized freeze-dried cortical bone and β-tricalcium phosphate covered by titanium-reinforced expanded polytetrafluoroethylene membranes was used for bone augmentation in an accident case in which a young female patient suffered anterior maxillary damage. Hydroxyapatite-coated implants were placed in the newly formed bone-like material before prosthodontic reconstruction. A biopsy suggests the bone-like material was essentially normal lamellar and woven bone. (Implant Dent 1996;5:251–254)