Design and validation of a surgical guide for the retrieval of foreign body instruments in jaw / 解剖学报

Objective To design and validate a novel surgical guide for retrieval of foreign body in jaw. Methods Firstly, a surgical guide based on cone beam computed tomography and trephine technique was designed to remove broken dental instrument fragments. Its feasibility and accuracy were assessed by removing broken dental instrument in goat mandible, and then it was successfully applied in clinical cases. The linear and angular discrepancies between actual and planned columnar bone with imaginary fragment was analyzed. The euclidean distance was measured at the hex and apex of the columnar bone and the angle of axis deviation was also calculated. We obtained seven parameters (cdh, cda, hdh, hda, vdh, vda, and ad) to describe deviations. Results Mean central deviation at the hex and apex was (0.51 ± 0.14) mm and (0.62 ± 0.19) mm, respectively. Accompanying mean values were as follow: horizontal deviation at the hex was (0.48 ± 0.16) mm, horizontal deviation at the apex was (0.52 ± 0.22) mm, vertical deviation at the hex was (0.17 ± 0.09) mm, vertical deviation at the apex was (0.29 ± 0.13) mm, and angular deviation of (5.38 ± 3.43) degrees. In a clinical case, the guide successfully located and removed the fracture file. Conclusion This study reveals that this kind novel surgical guide could aid to locate and remove the foreign body in jaw.

Finite element modeling of individual maxillofacial hexahedron based on mapping method / 医用生物力学

Objective To establish patient-specific hexahedral finite element mesh model for the maxillofacial surgery. Methods A standard and common hexahedral finite element mesh model for the face soft tissue was first built by semi-automatic procedure, and the an individual facial hexahedral mesh was then generated by an example learning method based on volumetric mapping. Results It was convenient to generate a high quality patient-specific hexahedral mesh with geometric shape feature and mesh element quality preserved as much as possible with this method. Conclusions The new hexahedral mesh modeling method can provide high quality hexahedral mesh input for biomechanics analysis with good application prospect in many fields such as oral and maxillofacial surgery.

Nitric oxide regulates c-fos expression in osteoblastic cells induced by wall-shear / 浙江大学学报·医学版

<p><b>OBJECTIVE</b>To observe regulation of nitric oxide on c-fos expression in osteoblastic cells in response to changes in wall-shear stress in vitro.</p><p><b>METHODS</b>Isolated and purified osteoblastic cells from the calvaria of newborn SD rats were cultured and passaged. The third generation cells, pre-treated with 10% FBS DMEM, 0.3 mmol/L L-NMMA DMEM and 0.1 mmol/L SNP DMEM separately, were subjected to wall-shear stress of 1.2 Pa. Gene expression of the c-fos and NOS activity were studied before (0 min) and 10 min, 15 min, 30 min, 60 min after treated with wall-shear stress.</p><p><b>RESULT</b>The expression of c-fos mRNA was increased transiently after application of 1.2 Pa wall-shear stress in osteoblastic cells and peaked at 15 min. The expression of c-fos mRNA was decreased after pre-application with L-NMMA and increased after use of SNP.</p><p><b>CONCLUSION</b>Changes in the osteoblastic cells mechanical environment may cause a dramatic induction of NO and c-fos expression.</p>

Apoptosis induces by exogenous nitric oxide in Tca8113 cells / 浙江大学学报·医学版

<p><b>OBJECTIVE</b>To observe the apoptosis induced by exogenous NO in Tca8113 cells and to investigate the possible mechanism.</p><p><b>METHODS</b>SNP as NO donor was used to treat the tongue squamous cell carcinoma Tca8113 cells. Cytotoxic and apoptotic effects of NO on Tca8113 cells were examined by using MTT assay, acridine orange (AO) staining, Wright-Giemsa staining, agarose gel electrophoresis and flow cytometry. Western blot was performed for investigating the apoptotic mechanism.</p><p><b>RESULTS</b>NO had a remarkable proliferation inhibiting effect on Tca8113 cells. After being exposed to exogenous NO, Tca8113 cells showed series of apoptotic morphological changes such as cell shrinkage, nuclear condensation; and also showed DNA fragmentation, G2/M phase arrest as well as upregulation of the tumor suppressor P53 protein.</p><p><b>CONCLUSION</b>Exogenous NO has a proliferation inhibition and apoptosis induction effect on Tca8113 cells in a concentration and time-dependent manner, P53 protein may be involved in the apoptosis induced by NO.</p>

Activating protein-1 members in response to changes of wall-shear stress in osteoblastic cells / 华西口腔医学杂志

<p><b>OBJECTIVE</b>To observe activating protein-1 (AP- 1) members in response to changes of wall-shear stress in osteoblastic cells in vitro.</p><p><b>METHODS</b>Isolated and purified osteoblastic cells from the calvaria of newborn SD rats were cultured and subcultured. The third generation cells were subjected to wall-shear stress of 0.8 Pa, 1.2 Pa, 1.4 Pa and 1.6 Pa separately. Gene expression of the seven AP-1 members were studied before (0 h) and 10 min, 15 min, 30 min, 60 min after treated with wall-shear stress.</p><p><b>RESULTS</b>The expression of FosB, c-Fos, c-Jun, JunD and JunB mRNA increased transiently after application of 1.2 Pa wall-shear stress in osteoblastic cells compared to 0.8 Pa , 1.4 Pa and 1.6 Pa stress, and peaked at 15 min.</p><p><b>CONCLUSION</b>Mechanical environment changes in osteoblastic cells induced a dramatic induction of most of the AP-1 members.</p>