title: Reconstruction plates to bridge mandibular defects: a clinical and experimental investigation in biomechanical aspects.
abstract: A retrospective study of 68 patients was carried out to assess the complications arising from the use of reconstruction plates in the maintainance of space and contour following mandibular segmental resection. Skin or mucosal perforation, plate fracture and loss of screw retention were the main complications. The most susceptible sites to screw loosening in the plates were situated nearest to and farthest from the resection margin on the proximal residual segments. Some of the possible causative biomechanical mechanisms of plate failure were studied using photoelastic models simulating the types of mandibular defect and plate fixation. Isochromatic fringe analysis was used to analyse stress lines in the bone surrounding screws. It was found that, during functional loading, moment and shear forces produced high concentrations of squeeze and press stress in this bone, causing bone resorption with consequent loss of screw retention.
authors.affiliation: Department of Oral and Maxillofacial Surgery, School of Stomatology, Beijing Medical University, P.R. China.
authors.forename: Z
authors.initials: Z
authors.lastname: Yi
authors.forename: Z
authors.initials: Z
authors.lastname: Jian-Guo
authors.forename: Y
authors.initials: Y
authors.lastname: Guang-Yan
authors.forename: L
authors.initials: L
authors.lastname: Ling
authors.forename: Z
authors.initials: Z
authors.lastname: Fu-Yun
authors.forename: Z
authors.initials: Z
authors.lastname: Guo-Cheng
mesh_terms: D001718:Birefringence; D001860:Bone Plates / Q000009:adverse effects*; D001862:Bone Resorption / Q000209:etiology; D001863:Bone Screws / Q000009:adverse effects; D016009:Chi-Square Distribution; D019245:Compressive Strength; D003799:Dental Stress Analysis; D004548:Elasticity; D019544:Equipment Failure Analysis; D006801:Humans; D019248:Jaw Fixation Techniques / Q000009:adverse effects / Q000295:instrumentation*; D008334:Mandible / Q000601:surgery*; D008339:Mandibular Neoplasms / Q000534:rehabilitation / Q000601:surgery; D008341:Mandibular Prosthesis / Q000009:adverse effects; D008954:Models, Biological; D011475:Prosthesis Failure; D019651:Plastic Surgery Procedures; D012189:Retrospective Studies; D013718:Tensile Strength