ABSTRACT
BACKGROUND: Biomechanical stability in patients in whom mandibular prognathism was corrected with different fixation methods during bilateral sagittal split osteotomy (BSSO) surgery remains controversial and needs to be clarified. METHODS: A three-dimensional (3D) finite element (FE) model of the mandible was developed to simulate the biomechanical responses of osteo-synthesis screws and the stability of different screw-placement arrangements in BSSO. Six types of fixation methods for the osseous segments were simulated with two or three screws in different placement arrangements to avoid injury to the inferior alveolar nerve. RESULTS: A triangular configuration of the screw position across the nerve presented less stress loading than the linear configuration, and hence provided better stability as the preferred fixation method for BSSO of the mandible. When the screws were aligned in a linear setting, the stress values were 4 times higher, implying a less stable fixation. Neither two nor three screws applied at the superior border appeared to be better at exploiting the increased thickness of the cortical bone encountered in this region. CONCLUSIONS: According to the 3D-FE analysis, the configuration with three screws inserted in a triangular shape across the inferior alveolar nerve (Type 4) demonstrates the best rigidity among six screw-placement configurations. Three 2.3-mm diameter bi-cortical screws were considered a sufficient fixation tool after BSSO of the mandible.
Subject(s)
Fracture Fixation, Internal/instrumentation , Prognathism/surgery , Biomechanical Phenomena , Bone Screws , Equipment Design , Finite Element Analysis , Humans , Male , Materials Testing , OsteotomyABSTRACT
<p><b>OBJECTIVE</b>To explore the enhancing effect of compound Kusheg injection in chemotherapy for patients with stage III and IV non-small cell lung cancer (NSCLC).</p><p><b>METHODS</b>A total of 286 patients with advanced NSCLC were enrolled in this study. The patients were treated with either compound Kusheng injection in combination with NP (NVB + CBP) chemotherapy (vinorelbine and carboplatin, n = 144), or with NP (NVB + CBP) chemotherapy alone (n = 142). The chemotherapy was performed for 4 cycles of 3 weeks, and the therapeutic efficacy was evaluated every 2 weeks. The following indicators were observed: levels of Hb, WBC, PLT and T cell subpopulations in blood, serum IgG level, short-term efficacy, adverse effects and quality of life.</p><p><b>RESULTS</b>The gastrointestinal reactions and the myelosuppression in the combination chemotherapy group were alleviated as compared with the chemotherapy alone group, showing a significant difference (P < 0.05). CD(8)(+) cells were markedly declined in the combination chemotherapy group, and the CD(4)(+)/CD(8)(+) ratio showed an elevation trend in the chemotherapy alone group. The KPS scores and serum IgM and IgG levels were higher in the combination chemotherapy group than those in the chemotherapy alone group (P < 0.01 and P < 0.05). The serum lgA levels were not significantly different in the two groups.</p><p><b>CONCLUSION</b>The compound Kusheng injection plus NP chemotherapy regimen shows better therapeutic effect, reduces adverse effects of chemotherapy and improves the quality of life in patients with stage III and IV NSCLC.</p>
