Expression of inducible nitric oxide synthase in cartilage in progression of temporomandibular joint osteoarthritis / 华西口腔医学杂志

<p><b>OBJECTIVE</b>To study the expression of inducible nitric oxide synthase (iNOS) in cartilage of temporomandibular joint osteoarthriti (TMJOA), and to evaluate the role of iNOS in the progression of TMJOA.</p><p><b>METHODS</b>The goats were used and TMJOA was induced by injection of collagenase in upper joint space. The joints were obtained and were investigated by using immunohistochemistry at 2, 4, 12, 24 weeks after injection.</p><p><b>RESULTS</b>Almost no expression of iNOS in normal cartilage of TMJ. In the diseased joints, strong or definite iNOS reactivity was expressed.</p><p><b>CONCLUSION</b>iNOS plays an important role in the progression of TMJOA.</p>

Recombinant human BMP-2 accelerates bone formation of mandibular distraction osteogenesis in rabbits / 华西口腔医学杂志

<p><b>OBJECTIVE</b>To study the effects of rhBMP-2 on bone formation of mandibular distraction osteogenesis in rabbits.</p><p><b>METHODS</b>Bilateral mandibular osteotomies were performed in 12 mature rabbits. 5 mg rhBMP-2 with the collagen carrier was implanted in the osteotomy site of one side of the mandibles. Only the collagen sponge was placed in the contra-lateral side as control. The mandibles of 8 rabbits were lengthened by 6mm using a custom-made distractor. At 4 weeks after the end of distraction, all animals were killed and the distracted calluses were harvested and processed for histological, scanning electron microscopic, as well as Ca/P ratio analysis.</p><p><b>RESULTS</b>The regenerated bone was found in the distraction gap after mandibular lengthening. The mandibular side treated with rhBMP-2 had greater amounts of new bone formation and earlier mineralization than contra-lateral side (non-rhBMP-2 treated).</p><p><b>CONCLUSION</b>Recombinant human BMP-2 appears to be able to accelerate bone formation of mandibular distraction osteogenesis in rabbits.</p>

The effects of L-NMMA on experimental temporomandibular joint osteoarthrosis in goats / 中华口腔医学杂志

<p><b>OBJECTIVE</b>To investigate the effects of repeated injections of L-NMMA on a goat model with osteoarthrotic temporomandibular joint (TMJ) disease.</p><p><b>METHODS</b>Eight goats were selected in this study. Bilateral TMJ osteoarthrosis (OA) was induced by injecting 0.5% collagenase. L-NMMA was injected into one side of TMJs at 4 weeks after collagenase injection (one time every three days). Another joint as control was simultaneously injected using 0.9% saline solution. All goats were killed at 12 weeks after collagenase injection. The TMJ specimens were harvested and processed for histological examination. Modified Mankin's grading score system was used for evaluating changes in the TMJ.</p><p><b>RESULTS</b>The control side of TMJs showed severe osteoarhrotic changes in the condyle whereas the L-NMMA-treated TMJs showed less degenerative alterations. The histologic score was 3.83 in the L-NMMA treated side, and 6.33 in the control. There was a significant difference in osteoarthrotic changes between the L-NMMA-treated and control TMJs (P < 0.01).</p><p><b>CONCLUSIONS</b>Repeated intra-articular injection of L-NMMA into TMJ may play a role in inhibiting TMJOA progression.</p>