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Background Resorbable devices have recently been adopted in the field of orthognathic surgery with controversies about their postoperative skeletal stability. Hence, we determined the long-term skeletal stability of unsintered hydroxyapatite/poly-l-lactic acid (HA/PLLA) mesh for osteofixation of mandibular sagittal split ramus osteotomy (SSRO), and compared it with that of titanium miniplate. Methods Patients were divided into resorbable mesh and titanium miniplate fixation groups. A comparative study of the change in the mandibular position was performed with preoperative, 1-day, 6-month, and 2-year postoperative lateral cephalograms. Results At postoperative 6 months—compared with postoperative 1 day, point B (supra-mentale) was significantly displaced anteriorly in the titanium-fixation group. Moreover, at postoperative 2 years—compared with postoperative 6 months, point B was significantly displaced inferiorly in the titanium-fixation. However, the HA/PLLA mesh-fixation group did not show any significant change with respect to point B postoperatively. Conclusions The HA/PLLA mesh-fixation group demonstrated superior long-term skeletal stability with respect to the position of mandible, when compared with the titanium-fixation group.

Background Laminoplasty is an effective procedure for treating cervical spondylotic myelopathy (CSM). Little information is available regarding the surgical outcomes of expansive open-door laminoplasty (EOLP) when securing with titanium miniplates without bone grafting. This study is aimed to elucidate the efficacy of and problems associated with EOLP secured with titanium miniplates without bone grafting, thereby enhancing future surgical outcomes. Methods This is a retrospective study. The study participants comprised 104 patients who underwent cervical EOLP secured with titanium miniplates without bone graft for CSM treatment between August 2005 and March 2011. The clinical results were evaluated based on the Japanese Orthopedic Association (JOA) and Nurick scores. The radiographic outcomes were determined based on plain film and magnetic resonance imaging findings, which were assessed and compared. Results Lateral cervical spine X-rays exhibited improvement in the Pavlov ratio of the spinal canal at 1 day postoperation, and this ratio did not change at 1 year postoperation. The mean cervical curvature from C2 to C7 decreased 0.21° ± 10.09° and the mean cervical range of motion was deteriorated by 35% at 12 months (P

The present report describes the application of a miniplate in the hard palate of a 36-year-old patient with a large anterior maxillary defect. The combination of orthodontic elastics with a titanium miniplate improved the stability of the prefabricated prosthesis. This structure retained the ointment gauze covering the wounds and maintained the facial contour. In addition, contracture deformity was prevented by insertion of the prefabricated prosthesis intraoperatively or immediately postoperatively. Furthermore, a soft diet could be ingested immediately postoperatively. The miniplate also supported the anterior part and the definitive prosthesis. This prosthesis restored adequate masticatory, deglutitive, and speech functions and maintained the facial contour with minimum overloading of the remaining teeth.Dental rehabilitation; Maxillary defect; Titanium miniplate.

Aim This study investigates the changes occurring in the mechanical characteristics of osteosynthesis titanium miniplates when exposed to repeated sterilization cycles. Methods For this study Medicon © titanium miniplates were used. The characteristics of miniplates were evaluated using the Penetration Resistance test, MSC/Pal2 Software, and the Finite Elements Method (F.E.M.). Surface roughness measurements were also carried out. Statistical analysis was conducted using the One way ANOVA model. The significance level was set at >0.05. Results The one way ANOVA analysis between HV value and increased sterilization cycles showed P > 0.029; between the Ra value and increased sterilization cycles it was P > 0.325; between the Rq value and increased sterilization cycles it was P > 0.703. The Finite Element Model shows an amplified deformed shape of the miniplate at a load of 196 [N]. At this load value the equivalent ‘von Mises stress’ reaches the value of σ P0.2 , shown by the ASTM F 67–95 standard. Stress distribution comparison between the six-holed plate and the equivalent straight miniplate shows more consistent behaviour for the Medicon © miniplate. The rigidity of the Medicon © miniplate is 14.46, lower than that for the equivalent straight miniplate ( R = 23.4). The ANOVA analysis between the break load and increased sterilization cycles showed P > 0.175; between the break position and increased sterilization cycles it showed P > 0.016. Conclusions Experimental static tests have shown that all tested miniplates did not have notable differences and this suggests that sterilization cycles do not affect mechanical characteristics.