Expression and distribution of TNF-α and PGE2 of periodontal tissues in rat periodontitis model

OBJECTIVE@#To simulate the expression of TNF-α and PGE2 of periodontal tissues in rat periodontitis model.@*METHODS@#40 Wistar rats were randomly divided into the periodontitis group and the control group (n=20). After the successful establishment of periodontitis rat model, raising for six weeks before the animals were sacrificed. The periodontal tissues were obtained and made into slices. Observed the histopathological changes of the periodontal tissues and measured TNF-α, PGE2 levels change by immunohistochemistry, Western blot analysis and ELISA.@*RESULTS@#TNF-α, PGE2 expression of the periodontitis group was significantly higher than that in the control group, the difference was significant (P<0.05).@*CONCLUSIONS@#The TNF-α, PGE2 expression of the rat periodontal tissue in the periodontitis group was significantly higher than the control group.

Experimental study of the bioresorbable collagen membrane used for guided bone regeneration around dental implants / 华西口腔医学杂志

<p><b>OBJECTIVE</b>To investigate the effects of using guided bone regeneration (GBR) technique with an bioresorbable collagen membrane for repairing bone defects around dental implants.</p><p><b>METHODS</b>In 12 mongrel dogs, pure titanium implants were immediately implanted in mandibles after extraction of the mandibular third and fourth premolars of both sides, in which standard bone defects of 3 mm x 3 mm x 5 mm were created at mesial side of the implants. The defects on right side were covered with Co membrane, the left side was uncovered as control. The dogs were sacrificed 1, 2, 4, 6 months postoperatively. The specimens were removed and studied by gross observation, X-ray radiograph, histological examination, scanning electron microscope (SEM) and pull-out test.</p><p><b>RESULTS</b>The quantity and quality of new bone formation in experimental side which bone defects covered with Co membrane were much better than that in the control side.</p><p><b>CONCLUSION</b>With the biodegradable property and excellent biocompatibility, Co membrane can be used for guided bone regeneration to promote the bone repair progress, and the promotion acts mainly at early stage of bone healing.</p>