In this study, we evaluated the usefulness of bioabsorbable poly-L-lactide (PLLA) mini-plates for bone fixation after Le Fort I osteotomy and bilateral sagittal split osteotomy (SSRO). The subjects were 19 patients, who received two-jaw surgery using titanium and PLLA mini-plates. Lateral cephalograms were taken before surgery (T1), immediately after surgery (T2), and more than six months after surgery (T3). Changes in the measurement points were statistically analyzed. There was no statistical difference in the postoperative skeletal difference between the two groups. The post-operative stability of PLLA mini-plates is comparable to that of titanium mini-plates. PLLA mini-plates are considered to be clinically useful.

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The clinical efficacy of new resorbable plate and screw fixation devices (PLDG osteosynthesis system) for jaw stabilization in bimaxillary orthognathic surgery was evaluated in this study.
PLDG plates and screws were fabricated from a unique tripolymer which was a composite of poly L-Lactide/D-Lactide/Glycolide (PLDG) with a molecular ratio of 85/5/10. It was heated by immersion in hot sterilized water until it became plastic and was then fitted to the surface of the bone.
The skeletal stability after Le Fort I osteotomy and the bilateral sagittal split ramus osteotomy was evaluated on lateral cephalograms in 46 patients with mandibular prognathism.
The subjects were divided into three groups based on the types of osteosynthesis systems used. Group TI consisted of 22 patients in whom a titanium osteosynthesis system was used for bone fixation. Group LA consisted of 14 patients in whom the PLLA osteosynthesis system was used, and group DG comprised 10 patients in whom the PLDG osteosynthesis system was used for bone fixation at the bilateral border of the piriform aperture.
Lateral cephalograms were taken before surgery, immediately after surgery, and at least six months after surgery to examine the usefulness of bioresorbable osteosynthesis system for bone fixation in orthognathic surgery.
Changes in the positions of point A, ANS, point B and menton were examined in this study.
The postoperative changes of the maxilla and mandible were less than 1 mm on cephalograms except the horizontal changes at point B in group LA and group DG.
There was no statistical difference in the postoperative skeletal stability among the three groups.
The results of this study suggest that the PLDG osteosynthesis system is clinically useful since the system fits the bone surface tightly and maintains the postoperative skeletal stability.

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We performed surgical simulation using plaster models prior to actual orthognathic surgery in patients with jaw deformity. In this study, to achieve more accurate positioning of bone segments during surgical simulation, maxillofacial computed tomography (CT) images and three-dimensional (3D) dentition model images were integrated in order to produce maxillofacial models with detailed dentition. Two adult patients with jaw deformity were selected for this study. The methods were as follows: 1) production of ceramic ball-attached reference splints, 2) acquisition of facial skeletal information from X-ray CT, 3) acquisition of dentition model information from X-ray micro-CT, 4) 3D image integration of facial skeletal information and dentition model information using reference splints for positioning, 5) production of a facial skeletal model using rapid prototyping, and 6) surgical simulation using the model produced. 3D imaging of jaw morphology and model production in each case was performed for more accurate surgical simulation. A comparison between the models after simulation and postoperative CT images was useful for feedback from oral surgeons. Furthermore, it became possible to give a more precise explanation to patients, and consistency between expected postoperative morphology and patients' esthetic requests was achieved. The results suggest that the production of models reflecting detailed dentition information can be a useful tool in orthognathic surgery.

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It is well known that anti-retroviral therapy (ART) has improved the prognosis of Acquired Immuno-Deficiency Syndrome (AIDS) patients. Therefore, the number of surgeries for patients with AIDS is tending to increase recently. In this paper, we present an outline of surgical orthodontic treatment for a patient with AIDS.
A 39-year-old man presented with the chief complaint of mandibular protrusion. He had been treated with ART since he had developed AIDS at the age of 38 years. His preoperative CD4 and HIV RNA were 146/μand 8.8 copies/ml respectively. The diagnosis of skeletal mandibular protrusion was made. Sagittal split ramus osteotomy (SSRO) was performed under general anesthesia. On the following day, ART was resumed. The postoperative course was uneventful and he was discharged from our hospital 11 days after the surgery. One year after the operation, well-harmonized occlusion and facial appearance were obtained, and he remains in good general condition.

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Introduction: An absorbable plate with good tissue affinity and without necessity of removal is a reliable osteosynthetic material used to treat jaw deformity. However, bending the plate with two kinds of conventional benders is operationally complicated, particularly when forming appropriate steps. This paper reports a case of jaw deformity treatment in which a new custom-made bender (Step Bender^TM) and tap screws for tentative fixation were used to adjust and fix the absorbable plate.
Case report: An 18-year-old male patient with a clinical history of untreated occlusal dysfunction noticed at approximately 13 years old. Following a visit to an orthodontist, the patient was referred to our hospital in November 2007 with the chief complaint of occlusion deficiency. Mandibular prognathism was diagnosed by cephalometric analysis. In accordance with the patient's wishes and judging from the displacement distances, the treatment procedures were decided to be: anterior displacement of the maxilla; posterior displacement followed by counterclockwise rotation of the mandible; and anterosuperior displacement of the mentum. An absorbable plate was used in view of the patient's condition.
Under general anesthesia, conventional two-jaw osteotomy was performed in August 2009. Osteosynthesis was applied after maxillary osteotomy in Le Fort I. The plate bender “Step-Bender^TM” developed by Takiron Company for maxillary osteotomy was used for plate bending. The plate was held in an appropriate position with the Step-Bender^TM and heated once. Then, the plain plate could be bent manually in both upward and downward directions simultaneously to simplify the configuration and shorten the operation time. Newly developed “tap screws for tentative fixation” were also used in the procedure. The “tap screws for tentative fixation” were used for cutting the tap, and then for fixing the plate temporally, thus improving the efficiency of the screw fixing procedure. The postoperative position of the absorbable plate was confirmed in 3DCT images and smooth osteosynthesis was confirmed with occlusion control.
The patient remained under postoperative observation for two years with no problem.Conclusion: The case in this report demonstrated the successful clinical application of an absorbable plate with a new tool, Step-Bender^TM, and temporary fixing tap screws for tentative fixation. Both apparatuses were considered to be suitable for this case.

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