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21.
PURPOSE: The sternocleidomastoid (SCM) myocutaneous flap remains an important tool in head and neck reconstruction. This article retrospectively reviews 40 consecutive SCM myocutaneous flaps used for the reconstruction after resection of oral squamous cell carcinoma with respect to reliability and complications. PATIENTS: From 1987 to 1997, 40 patients underwent SCM myocutaneous flap reconstruction of the oral cavity. The age and gender of the patients, site of primary tumor TNM stage, type of associated operation, and clinical course were analyzed. RESULTS: In 8 cases, partial epithelial loss over the skin paddle occurred with survival of the muscle and at least some of the dermis. Unilateral supraomohyoid neck dissection (SND) was performed in 11 cases, and unilateral functional neck dissection, which preserves SCM and/or internal jugular vein and/or accessory nerve, in 16 cases. Pathologically positive nodes were recognized in 14 of these 27 neck dissection cases; in 11 of these 14 cases, the neck lesion was controlled. CONCLUSION: The SCM myocutaneous flap appears to be simple to use and useful for reconstruction of the defect after resection of oral carcinoma, and the indications for this flap will be extended in accordance with the recent increases in the number of supraomohyoid and functional neck dissection cases.  相似文献   
22.
Objectives To assess the reproducibility of the mandibular cortical index (MCI) on panoramic radiographs among British and Japanese observers, and to investigate the difference between the British and Japanese observers in the definition of MCI.Methods Three observers, a Japanese oral radiologist, a British oral radiologist, and a British prosthodontist, classified the inferior cortex of the mandible on a set of 100 duplicated films of randomly selected panoramic radiographs twice, 2 weeks apart, using the MCI. The kappa index for intra- and interobserver agreement was calculated for the three observers.Results The kappa index for intraobserver agreement was moderate (0.56) to perfect (0.86) for the three observers. Interobserver agreement between the Japanese and the British oral radiologists was moderate at the first reading (kappa, 0.59) and substantial at the second (0.61). Interobserver agreement between the prosthodontist on the one hand and each of the oral radiologists on the other was fair (0.35, 0.38) at the first reading, but moderate (0.43, 0.60) at the second reading. The prosthodontist tended to overestimate the MCI compared with either of the oral radiologists.Conclusion Our results suggest that the definition of MCI used by Japanese observers is basically similar to that used by British observers, although some improvements in the definition of MCI would be necessary for clinical dental practice.  相似文献   
23.
The objective of this study is to develop a casting investment that prevents the blackening of the cast surface of noble metal alloys. The experimental investments were prepared using a gypsum-bonded investment in which the metallic powders such as boron (B), silicon (Si), aluminum (Al) and titanium (Ti) were added as oxidizing agents. An Ag-Pd-Cu-Au alloy was cast into the mold made of the prepared investment. The effect of the addition of each metal powder was evaluated from the color difference between the as-cast surface and the polished surface of the cast specimen. The color of the as-cast surface approached that of the polished surface with increasing B and Al content. A lower mean value in the color difference was obtained at 0.25-1.00 mass% B content. B and Al are useful as an additive in a gypsum-bonded investment to prevent the blackening of an Ag-Pd-Cu-Au alloy. The effects of Si and Ti powder addition could not be found.  相似文献   
24.
For patients with TMJ dysfunction, operators often change the condylar position by various methods. The aim of this study is to investigate how much the changes with time of condylar positions are related to the changes of clinical signs. The subjects were 584 joints of 127 patients with TMJ dysfunction to whom the serial lateral TMJ tomography was performed more than twice. In the most of cases where the condylar position had moved downward, inter-incisal distance had increased and TMJ noise had ameliorated. Furthermore, in many cases where the condylar position had moved forward, the amelioration of the TMJ pain was observed. It was considered that those ameliorations occurred because the positional relationship between the condylar head and the articular disk or posterior attachment had been improved.  相似文献   
25.
The purpose of this study was to evaluate marginal leakage of composite resin restoration from cavities prepared by Er:YAG laser. The observation of the dentin surface after the application of laser irradiation was performed by LSM, the cutting surface showed a rough surface similar to scales, and exposed dentinal tubules were observed without striations or a smeared layer formation that were observed when using a rotary cutting device. Leakage tests revealed no significant differences in the marginal seal for both enamel and dentin between cavities prepared by Er:YAG laser irradiation and when using an air-turbine. In this study, the usefulness of cavity preparation by Er:YAG laser irradiation in composite resin restoration was suggested.  相似文献   
26.
To investigate the long-term effects of c-src deficiency on skeletal and dental tissues, we examined the lower jaws and long bones of c-src gene knockout (c-src KO) mice by histological and histochemical methods. Numerous multinucleated osteoclasts were distributed throughout the mandible in 5-wk-old c-src KO mice, but by 14 wk they had almost completely disappeared from the alveolar bone, leaving tartrate-resistant acid phosphatase (TRAP)-positive layers along the bone surface. Deposition of osteopontin-positive mineralized tissue, reminiscent of acellular afibrillar cementum (AAC), was confirmed along the TRAP-positive bone surface at 14 wk. The layer progressively thickened up to 21 months. A comparable mineralized layer was noted along the trabeculae of long bones as thickened cement lines. In the periostin-rich areas of jaw bones, but not in the long bones, portions of AAC-like mineralized layers were often replaced with and/or covered by acellular extrinsic fiber cementum (AEFC)-like tissue. These data suggest that the deposition of AAC-like mineralized tissue is a general phenomenon that may occur along inert or slowly remodeling bone surfaces under conditions characterized by reduced bone-resorbing activity, whereas the induction of AEFC-like tissue seems to be associated with the expression of certain molecules that are particularly abundant in the microenvironment of the periodontal ligament.  相似文献   
27.
Addition of medium incubated with normal rat gingival tissue to platelet-rich plasma inhibited ADP-induced platelet aggregation. The ability of rat gingiva to produce activity inhibiting platelet aggregation was enhanced by the addition of arachidonic acid. Diabetic rat gingiva failed to inhibit platelet aggregation but did produce the anti-platelet aggregating activity in the presence of arachidonic acid. Indomethacin blocked the production of anti-platelet aggregating activity. There was no difference in conversion of [1-14C]arachidonic acid to prostaglandins by normal and diabetic rat gingiva. These results suggest that an arachidonic acid metabolite released from gingiva during incubation inhibits platelet aggregation, and the synthesis of the metabolite is impaired in diabetic rat gingiva. A decrease in availability of arachidonic acid may be a causal factor of the defect in diabetic rat gingiva.  相似文献   
28.
29.
Parenchyma-sparing pancreatic resections have been reported increasingly in recent years; however, for multifocal diseases involving the head and the tail of the pancreas, total pancreatectomy is still the preferred procedure. The possible consequence of this procedure is loss of normal pancreatic parenchyma, resulting in insufficiency of pancreatic exocrine and endocrine functions. Various types of limited resection have been introduced for isolated or multiple pancreatic lesions, depending on the location of the tumor. Even for multifocal diseases, if the pancreatic body is spared, a middle-preserving pancreatectomy (MPP) can be performed to assure maximal pancreatic function and uncompromised quality of life. Yet, few papers have introduced the feasibility of MPP for a better outcome. This report describes a new surgical technique for MPP using an alternative approach for the remnant pancreas anastomosis. We used this technique successfully to remove a bifocal neoplasm: adenocarcinoma of the distal bile duct and mucinous cyst adenoma in the tail of the pancreas.  相似文献   
30.

Purpose

We assessed the incidence of coronary artery disease (CAD) during hospitalization after emergency surgery for a type A acute aortic dissection.

Methods

A total of 123 patients underwent multi-slice computed tomography (MSCT) scans during an early stage after surgery. The patients were divided into two groups: group I consisted of 14 patients (11.4 %) who had coronary artery stenosis of more than 75 % on MSCT, and group II consisted of 109 patients (88.6 %) who had no coronary lesions.

Results

The prevalence of diabetes, dyslipidemia and a smoking history was significantly higher in group I. Although the serum low-density lipoprotein cholesterol levels were similar, the high-density lipoprotein cholesterol (HDL) level was significantly lower in group I (36.4 ± 7.9 mg/dl) than in group II (49.6 ± 13.5 mg/dl, P = 0.0005). The maximum carotid intima-media thickness (IMT) was significantly thicker in group I (1.17 ± 0.37 mm) compared to group II (0.96 ± 0.33 mm, P = 0.0297). The logistic regression analysis detected that a carotid IMT over 1.1 mm (odds ratio 4.35, P = 0.0371) and HDL less than 40 mg/dl (odds ratio 3.90, P = 0.0482) were predictors for CAD.

Conclusions

CAD screening should be recommended for patients with aortic dissection who have several atherosclerosis risk factors, even after emergency surgery.  相似文献   
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