下顎枝矢状分割術後におけるオトガイ領域知覚神経麻痺の発生要因に関する臨床的研究

取得学位 : 博士（医学）, 学位授与番号 : 医博甲第1490号 , 学位授与年月日 : 平成13年6月30日, 学位授与大学 : 金沢大

Resolution of pulmonary multiplanar reconstruction images from 0.5-mm theoretical isotropic data: a fundamental study using an inflated and fixed lung specimen.

The aim of the present study was to define the resolution of multiplanar reconstruction (MPR) of the lung from &#34;theoretical isotropic data.&#34; Using inflated and fixed lung specimens of the pig placed in the chest wall phantom, 0.5-mm isotropic data were obtained with 2 different helical pitches: 1:7 (high-quality mode) or 1:13, (high-speed mode), and 2 different tube currents: 250 mAs (high-tube-current mode) or 100 mAs (low-tube-current mode), with or without overlapping reconstruction. MPRs were created from these axial data. The diameter of the smallest visible pulmonary artery and bronchi of these CT images were measured on the corresponding slices of the specimen. The high-speed and low-tube-current mode significantly degraded the image quality due to increased noise. The smallest visible pulmonary artery and bronchus resolved on MPRs from axial-spiral data with 0.5-mm collimation were approximately 100 micrometer and 1,000 micrometer in diameter, respectively. In conclusion, helical pitch and tube current influence the resolution of MPR of the lung.</p

Relationship Between the Morphologies of the Masseter Muscle and the Ramus and Occlusal Force in Patients With Mandibular Prognathism

金沢大学医学部附属病院歯科口腔外科Purpose: The purpose of this study was to examine the relationship between the morphologies of the masseter muscle and the ramus and occlusal force in patients with mandibular prognathism. Patients and Methods: The study group consisted of 71 patients with mandibular prognathism. They were divided into 2 groups, consisting of prognathism with or without symmetry, determined by frontal cephalogram analysis. All patients underwent 3-dimensional (3D) computed tomography (CT) and occlusal force was recorded with pressure-sensitive sheets. Results: In the cross-sectional area of masseter muscle, there were no significant differences between the right and left sides in the symmetry and asymmetry groups. In occlusal force, there was no significant difference between the symmetry and asymmetry groups. Occlusal force was not significantly correlated to the cross-sectional area of the ramus, but it was significantly positively correlated to the cross-sectional area of the masseter muscle (P < .05). Conclusion: Occlusal force was associated with the ipsilateral cross-sectional area of masseter muscle in patients with prognathism; however, it was not associated significantly with the degree of mandibular deviation. © 2006 American Association of Oral and Maxillofacial Surgeons

A comparison of postoperative hypoesthesia between two types of sagittal split ramus osteotomy and intraoral vertical ramus osteotomy, using the trigeminal somatosensory-evoked potential method

金沢大学医学部附属病院歯科口腔外科The purpose of this study was to evaluate hypoesthesia of the lower lip using trigeminal somatosensory-evoked potential following 2 types of sagittal split ramus osteotomy (SSRO) and intraoral vertical ramus osteotomy (IVRO). There were 30 patients with mandibular prognathism, with and without asymmetry, who were divided into three groups: the Obwegeser method (Ob) group, the Obwegeser-Dal Pont method (ODP) group and the intraoral vertical ramus osteotomy (IVRO) group. The trigeminal somatosensory-evoked potential was recorded in the region of the lower lip and evaluated preoperatively and postoperatively. The average recovery periods from lower lip hypoesthesia in the IVRO and the Ob group were significantly shorter than in the ODP group (P < 0.05). In conclusion, IVRO showed the earliest recovery from hypoesthesia or an absence of hypoesthesia, and lower lip hypoesthesia was less with the Ob method than the ODP method.© 2006 International Association of Oral and Maxillofacial Surgeons

Expression of bone morphogenetic protein 2 and fibroblast growth factor 2 during bone regeneration using different implant materials as an onlay bone graft in rabbit mandibles

金沢大学医学部附属病院歯科口腔外科Objectives: The purpose of this study was to histologically and immunohistochemically evaluate bone regeneration using 3 different implant materials in rabbit mandibles and to compare the bone regenerative capability of these materials in an animal model. Study design: Adult male Japanese white rabbits (n = 48; 12-16 wks old; 2.5-3.0 kg) were divided into 4 groups, consisting of 12 animals each. The implant materials were β-tricalcium phosphate (β-TCP), autologous bone derived from the radius, and recombinant human bone morphogenetic protein 2 (rhBMP-2) with polylactic acid/polyglycolic acid copolymer and gelatin sponge (PGS) complex. After incising along the inferior border of the mandible, the materials were implanted as only grafts and covered by titanium mesh with screws. No material was implanted into the control group. The rabbits were killed at 2, 4, 8, 12, and 24 wks postoperatively, and formalin-fixed specimens containing titanium mesh were embedded in acrylic resin. The specimens were stained with hematoxylin and eosin. For immunohistochemical analysis, the specimens were treated with BMP-2 and fibroblast growth factor 2 (FGF-2) antibodies. Finally, they were examined microscopically. Results: The autologous bone induced substantially more new bone formation compared with β-TCP at 4 wks postoperatively. However, rhBMP-2/PGS induced new bone formation at 8 wks postoperatively. No growth of bony tissue was observed in the control group at any period. In the autologous bone and rhBMP-2/PGS groups, both BMP-2 and FGF-2 were observed later in the β-TCP group than in other groups. Conclusion: This study suggests that autologous bone as well as rhBMP-2/PGS implants induce expression of both BMP-2 and FGF-2 specifically at the operated sites, even at early stages. © 2007 Mosby, Inc. All rights reserved