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121.
The aim was to systematically review the maxillary incisor exposure and upper lip position changes with Le Fort I type osteotomies for advancement ± impaction with rigid internal fixation, taking into account the use of cinch sutures and VY closures. Electronic databases (Cochrane Library, Medline, Embase, and Web of Science) were searched using medical subject headings (MeSH), key words, truncations, and Boolean operators. Hand searching was also undertaken. Of 979 articles identified, 15 were included (11 retrospective, two prospective, and two unspecified). Relevant study details and outcomes were recorded on a spreadsheet, along with an assessment of their quality. In total, these studies assessed 419 patients (266 female, 118 male) with a mean age of 26.4 years (range 14–57 years). Soft tissue changes were assessed on lateral cephalometric radiographs. The mean maxillary hard tissue advancement and impaction ranged between 0.94 and 8.77 mm and −0.56 and 4.2 mm, respectively. The ranges of ratios demonstrated that from pronasale (0.24–0.35) to labrale superius (0.36–1.43), the soft tissues followed the underlying horizontal hard tissue movement increasingly more closely. Alar base cinch sutures and VY closures tended to increase these ratios. The soft tissue response was more variable vertically. None of the studies reported on maxillary incisor exposure change. More good quality prospective studies are needed.  相似文献   
122.
On the basis of our studies, we postulate that suture formation in Apert syndrome is related to the relative maturity of abutting calvarial bones. The fused coronal suture, a consistent manifestation at birth, develops first because the ossification centers of the frontal and parietal bones are in intimate contact early during intrauterine life. Calvarial immaturity and the megalencephalic brain characteristic of the Apert syndrome appear to work in concert to produce a widely patent midline calvarial defect extending from the glabella to the posterior fontanelle. Because sagittal growth in the coronal sutures cannot take place, the megalencephalic brain grows upward and laterally, and bulges forward through the midline defect. The defect fills in by coalescence of bony islands without proper suture formation because the gap to be bridged is so great that the time window for developing sutural interdigitations may have closed. Other sutures, such as the lambdoid, squamosal, and sphenotemporal, develop with normal interdigitations because abutting bone margins are in close enough proximity to permit suture formation. © 1996 Wiley-Liss, Inc.  相似文献   
123.
目的 总结吻合器在食管癌手术中重建消化道的临床经验,探讨器械吻合在食管癌手术中的应用价值.方法 回顾性分析974例食管癌患者应用吻合器行胃食管胸内吻合的资料.结果 发生吻合口瘘14例,其中10例治愈,4例死亡;吻合口狭窄27例,1例放置食管记忆合金支架、另26例行食管狭窄扩张后恢复正常饮食;吻合口出血2例,术中缝合治愈.结论 熟练的应用吻合器不但能减轻手术创伤,缩短胃食管吻合的时间,并且可明显降低吻合口瘘和狭窄等并发症的发生率.  相似文献   
124.
Shallow lingual vestibule and lack of keratinized attached mucosa are considered risk factors for the long‐term success of dental implants. This article describes a modified surgical approach accompanied by a free gingival graft to correct the shallow lingual/buccal vestibule and to increase the keratinized tissue around dental implants.  相似文献   
125.
目的:研究骨形成蛋白(bone morphogenetic protein,BMP)-2在犬面中份缝牵引成骨过程中的表达,探讨缝牵引成骨的机制.方法:18只12周龄杂种犬随机分为牵引成骨组12只和正常对照组6只,在牵引5、10、15 d,固定10、20 d,去固定1个月分别处死实验犬2只和对照犬1只,免疫组化法观察BMP-2在各骨缝的表达情况.结果:牵引期和固定期,BMP-2在实验犬各骨缝边缘大量增殖的未成熟成骨细胞、间充质细胞以及新生骨基质中呈阳性表达,对照犬也有少量表达.随着机械应力牵引, BMP-2在各骨缝表达量逐渐上升,在牵引15 d阳性表达最强,以后逐渐下降,到去固定1个月时表达水平接近正常.结论:机械牵张力刺激可以导致内源性BMP-2产生,BMP-2可能在缝牵引新骨生成过程中扮演重要的角色.  相似文献   
126.
The success of surgical procedures is strictly related to the biomechanical properties of the suture. Mechanical comparisons are scarcely reported in the literature, so the purpose of the present study was to evaluate and compare the mechanical behavior of different sutures commonly used in oral surgery in terms of traction resistance. Sutures made of eight different materials were analyzed: silk (S), polyglycolide-co-caprolactone (PGCL), polypropylene (PP), rapid polyglycolide (rPGA), standard polyglycolide (PGA), polyamide (PA), polyester (PE), and polyvinylidene fluoride (PVDF). For each material, three different sizes were tested: 3-0, 4-0, and 5-0. The breaking force of each suture was assessed with a uniaxial testing machine after being immersed in artificial saliva at 37 °C. The outcomes analyzed were the breaking force, the needle–thread detachment breaking-point and the node response after forward–reverse–forward (FRF) tying when subjected to a tensile force. The 3-0 rPGA provided the maximum resistance, while the lowest value was recorded for the 5-0 PGCL. In general, 3-0 and 4-0 gauges showed non-statistically significant differences in terms of needle–thread detachment. The highest needle–thread detachment was found for the 3-0 PGA, whereas the lowest value was observed for the 5-0 PGCL. After tying the knot with an FRF configuration, the thread that showed the highest resistance to tension was the 3/0 silk, while the thread with the lowest resistance was the 5/0 silk. These data should be considered so that the operator is aware of as many aspects as possible on the behavior of various materials to ensure successful healing.  相似文献   
127.
PurposeTo assess the clinical outcomes in patients with anterior cruciate ligament (ACL) proximal tears undergoing arthroscopic primary repair with knotless single suture anchor technique.MethodsThe first twenty-two consecutive patients with proximal ACL tears (Sherman types I and II and high-grade partial tears) treated with arthroscopic primary repair with single suture anchor technique were evaluated until 6 months post-operatively. Patients were evaluated with validated functional outcome measures (IKDC and Lysholm scores) and clinical tests for ACL stability.ResultsAt 6-month follow-up, 91% of patients (n = 20) achieved excellent outcome measures for IKDC and Lysholm scores and had complete stability of the ACL to clinical testing. Two patients with poor outcomes at six weeks; one with subjective instability and the other underwent revision surgery represented a failure rate of 9%. The median Lysholm score was 96 (IQ range, 96–100) and median IKDC subjective score was 87.40 (IQ range, 78.20–88.50) at 6-month follow-up. The improvement in Lysholm and IKDC scores over a period of six months post-operatively was statistically significant when compared to preoperative scores (p ≪ 0.0001). Maximum improvement in clinical outcomes is achieved in the first 6 weeks post-surgery with a slower increase thereafter, a time interval which may be considered as a figurative yield point for future work in this field.ConclusionArthroscopic ACL primary repair with knotless single suture anchor technique provides excellent short-term clinical outcomes in a carefully selected subset of patients with proximal ACL tears. More powered and longer duration studies are needed to understand longer term outcomes.Level of EvidenceLevel IV, therapeutic case series.  相似文献   
128.
现代手术越做越细,器械越来越精,但重建组织、修复切口离不开缝线。传统的普通丝线,待做完手术,成为永久异物存留于机体中,至少异物存留是美中不足,还有可能导致伤口感染手术失败。作为医生无不追求手术能没有缝线及异物存留,进口薇乔、国产华利康等可吸收人工合成缝合线因此深受欢迎。现报告我院在选择性手术中完全使用华利康3148例,效果满意。  相似文献   
129.
Suture anchors are extensively used in rotator cuff tear surgery. With the advancement of three-dimensional printing technology, biodegradable metal has been developed for orthopedic applications. This study adopted three-dimensional-printed biodegradable Fe suture anchors with double-helical threads and commercialized non-vented screw-type Ti suture anchors with a tapered tip in the experimental and control groups, respectively. The in vitro study showed that the Fe and Ti suture anchors exhibited a similar ultimate failure load in 20-pound-per-cubic-foot polyurethane foam blocks and rabbit bone. In static immersion tests, the corrosion rate of Fe suture anchors was 0.049 ± 0.002 mm/year. The in vivo study was performed on New Zealand white rabbits and SAs were employed to reattach the ruptured supraspinatus tendon. The in vivo ultimate failure load of the Fe suture anchors was superior to that of the Ti suture anchors at 6 weeks. Micro-computed tomography showed that the bone volume fraction and bone surface density in the Fe suture anchors group 2 and 6 weeks after surgery were superior, and the histology confirmed that the increased bone volume around the anchor was attributable to mineralized osteocytes. The three-dimensional-printed Fe suture anchors outperformed the currently used Ti suture anchors.  相似文献   
130.
目的:建立大鼠大脑中动脉闭塞(MCAO)缺血再灌注模型,探索再灌注后Cx43蛋白的表达模式。方法75只大鼠随机分为MCAO组(60只)和假手术组(15只)。MCAO组均行MCAO手术,术后根据缺血再灌注时间分为0.5、4、12、24 h 4个亚组,每组15只;假手术组不插入线栓。各组进行改良神经损伤严重程度评分(mNSS)、脑组织TTC染色及神经元尼式染色,Western blot及免疫组织化学方法检测各组脑组织Cx43蛋白的表达并进行统计学分析。结果 MCAO组造模成功率75%。MCAO组大鼠mNSS评分明显高于假手术组(P<0.05),脑梗死面积增加,额顶叶皮质区神经元大量损伤。Western blot结果显示:假手术组及MCAO 0.5、4、12、24 h组Cx43表达量分别为0.23±0.12、0.58±0.18、0.78±0.07、0.61±0.05和0.27±0.07, MCAO 0.5、4、12 h组与假手术组差异均有统计学意义(P<0.05),而MCAO 24 h组与假手术组差异无统计学意义(P>0.05)。免疫组化结果显示:MCAO组侧脑室下区Cx43的表达在0.5 h开始升高,4 h达高峰,12 h逐渐下降,直至24 h恢复基线水平;与Western blot结果一致。结论 Cx43蛋白在脑缺血性再灌注损伤发生、发展中起重要作用。  相似文献   
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