Narrowing and sliding genioplasty procedure combined with mandibular outer cortex ostectomy technique to correct square jaw in short face / 中华整形外科杂志

<p><b>OBJECTIVE</b>To evaluate the the feasibility and effectiveness of narrowing and sliding genioplasty combined with mandibular outer cortex ostectomy technique to reshape a square jaw in short face.</p><p><b>METHODS</b>From July 2005 to October 2009, a total of 57 patients received narrowing and sliding genioplasty combined with mandibular outer cortex ostectomy procedure to correct square jaw in short face. All the patients had standard frontal and lateral cephalometric radiographs, panoramic radiographs, and were photographed preoperatively and postoperatively to assess their face contour. The alteration of mandibular angle, mental contour and width of lower face was observed for 6 to 24 months postoperatively. Questionnaires were used to assess the patients' satisfactory.</p><p><b>RESULTS</b>It showed that the postoperative lower face had narrowed and become softer, slender and oval, with a slick mental region. The final aesthetic outcomes were quite satisfactory in all cases from both the view of surgeons and patients.</p><p><b>CONCLUSIONS</b>Narrowing and sliding genioplasty combined with mandibular outer cortex ostectomy procedure could efficiently adjust the shape and position of chin to obtain a good proportion of the lower face, and to change square and short face to slender oval one by single operation in accordance with the fashionable aesthetics in orientals.</p>

Correction of low angel-square jaw with mandibular "V-Line" ostectomy combined with mandibular outer cortex ostectomy / 中华整形外科杂志

<p><b>OBJECTIVE</b>To evaluate the feasibility of mandibular "V-Line" osteotomy combined with mandibular outer cortex osteotomy for correction of low angle-square jaw.</p><p><b>METHODS</b>From Jul. 2005 to Nov. 2007, 31 patients with low angle-square jaw were corrected with mandibular "V-Line" osteotomy combined with mandibular outer cortex osteotomy. The patients were followed up for 6-24 months. Pre- and Post-operative standard images and X-ray cephalometric examination were used to assess the therapeutic effect.</p><p><b>RESULTS</b>The wounds were healed primarily in all the 31 cases with no severe complication. The lower labial numbness was happened in 13 cases, which was recovered within 4 months. All the patients achieved esthetic improvement at the frontal and lateral view. The mandibular angle and the mandibular plane angle reached 110 degrees - 120 degrees and 25 degrees - 30 degrees after operation. The distance between the angles was decreased.</p><p><b>CONCLUSIONS</b>The low angle-square jaw can be corrected satisfactorily with mandibular "V-Line" osteotomy combined with mandibular outer cortex osteotomy.</p>

Osteoblastic differentiation and gene expression profile change in rat bone marrow mesenchymal stem cells after a single period of mechanical strain / 华西口腔医学杂志

<p><b>OBJECTIVE</b>To evaluate the osteoblastic differentiation and compare the difference in the gene expression of rat bone marrow mesenchymal stem cells (MSCs) affected by a single period of mechanical strain.</p><p><b>METHODS</b>Bone marrow MSCs were harvested from the femurs and tibiae of SD rats and cultured in vitro. A four-point bending apparatus were used to perform a single 40-minute period of 2,000 microepsilon mechanical strain on these MSCs. The proliferation of the MSCs was tested by MTT on scheduled date, and the osteoblastic differentiation of the MSCs was measured by testing the expression of osteocalcin and alkaline phosphate (ALP) activity of these cells. In addition, we have investigated the possible mechanisms underlying the action of the single 40-minute period of 2,000 microepsilon mechanical strain on these MSCs, after profile blotted and handled by bioinformation, the gene expressions of these two periods of MSCs were examined.</p><p><b>RESULTS</b>The MSCs have grown well in vitro. Our experiment showed that mechanical environment did not weaken the proliferation of the MSCs. However, the ALP activity and the expression of osteocalcin were significantly up-regulated by the 2,000 microepsilon mechanical strain. Using the 27 K Rat Genome Array, 416 different expressions were found. The rate of different genes was 2.8%, of which the expressions of 247 genes increased (61 genes remarkably increased) and 169 genes decreased (74 genes remarkably decreased) in these two periods of MSCs.</p><p><b>CONCLUSION</b>Mechanical strain induced the osteoblastic differentiation of the MSCs, which may be attributed to the different gene levels.</p>