1998 Volume 52 Issue 2 Pages 211-223
The purpose of this study was to investigate the effects of the polyvinylidene fluoride (PVDF) piezoelectric porous membrane on bone regeneration. The PVDF piezoelectric porous sheet was prepared as a membrane for guided bone regeneration technique, which involved 70% pores 0.45μm in average diameter and was 125μm in thickness and 2.6pC/N in piezoelectric constant. Non piezoelectric PVDF porous membrane was also used for a comparison. For three adult beagles bone cavities 4 mm in diameter reaching the marrow space in bilateral mandibles were prepared three months after the bilateral 2nd, 3rd and 4th premolars and 1st molars had been extracted. Of the four bone cavities, two were covered with the PVDF piezoelectric porous membrane (experimental group), one was covered with the nonpiezoelectric PVDF porous membrane (comparison group), and the remaining one was left as it was without covering (control group). After six weeks from the surgery, the specimen blocks were removed from the defect areas for histopathological evaluation. The four specimens corresponding to the central portion were histopathologically studied by microradiograms, fluorescent labeling observation, and conventional staining observation. The following results were obtained : 1. In the control groups, the new bone tissue grew in a hollow shape. 2. In the comparison groups, the original bone appearance was maintained by the membrane. In 50% of specimens, the superior region of the marrow space was not closed with newly formed bone. No new bone tissue was formed at the crest of the existing alveolar bone in all the specimens. 3. In the experimental groups covered with PVDF piezoelectric porous membrane, most of the bone defects were restored by bone regenerations with the bone contour being kept in original appearance. In 79% of specimens, the bone defects between the bone cavity and the marrow space was covered newly formed bone. At the crest of the existing alveolar bone, the new bone tissue was found in all the specimens. 4. With the PVDF piezoelectric porous membrane, new bone tissue was formed and mineralized faster than with other GBR membranes. The foregoing results suggest that the PVDF piezoelectric porous membrane may be a superior material in bone regeneration and multiplication for GBR technique.
