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41.
In the study the influence of different dental technical tools on the surface temperature and phase composition of fixed dental prostheses (FDPs) made of yttria-partially stabilized zirconia polycrystals (3Y-/4Y-/5Y-PSZ) was investigated. FDPs were fabricated by using computer-aided manufacturing (CAM). The FDPs were treated with a contra-angle handpiece equipped with different burs and polishers. The resulting surface temperatures were measured with a thermographic camera, and the resulting phase transformations were investigated by X-ray diffraction and quantified by Rietveld refinement. Processing with burs resulted in no phase transformation, but a preferred orientation shift. Using coarse polisher induced a phase transformation to the rhombohedral phase, while fine polishers produced no relevant phase transformations and no preferred orientation shift. Compared to the monoclinic phase (ca. 9% theoretical volume increase), which is associated with low-temperature degradation (LTD), the rhombohedral phase is much more voluminous (ca. 15% theoretical volume increase) and distorted and, therefore, has a greater degradation potential.  相似文献   
42.
目的通过Meta分析对使用人工补片进行食管裂孔重建的效果和安全性进行评价。方法检索Pubmed和Cochrane数据库2007年4月10日以前有关使用人工补片进行食管裂孔重建的随机对照实验,使用Cochrane图书馆提供的Review Manager4.2软件对入选实验的数据进行合并分析。主要评价指标包括术后裂孔疝发生率和由补片引起的脏器磨损。结果有7项随机对照实验,其中3项实验满足纳入标准和排除标准而入选Meta分析。共有280名研究对象纳入分析,其中使用人工补片进行裂孔重建的患者(n=137)在随访期内有8例(5.83%)发生裂孔疝,对照组(n=143)有33例(23.08%)发生裂孔疝,相对危险度RR=0.30(95%CI,0.15-0.62,P=0.001),随访期内没有观察到因补片磨损引起的脏器损伤。结论使用人工补片进行裂孔重建明显降低术后近期裂孔疝的发生危险,具有良好的应用前景,但远期效果和安全性有待长期观察的结果进一步明确。  相似文献   
43.
Purpose of ReviewThe role of the meniscus in preserving the biomechanical function of the knee joint has been clearly defined. The hypothesis that meniscus root integrity is a prerequisite for meniscus function is supported by the development of progressive knee osteoarthritis (OA) following meniscus root tears (MRTs) treated either non-operatively or with meniscectomy. Consequently, there has been a resurgence of interest in the diagnosis and treatment of MRTs. This review examines the contemporary literature surrounding the natural history, clinical presentation, evaluation, preferred surgical repair technique and outcomes.Recent FindingsSurgeons must have a high index of suspicion in order to diagnose a MRT because of the nonspecific clinical presentation and difficult visualization on imaging. Compared with medial MRTs that commonly occur in middle age/older patients, lateral meniscus root injuries tend to occur in younger males with lower BMIs, less cartilage degeneration, and with concomitant ligament injury. Subchondral insufficiency fractures of the knee have been found to be associated with both MRTs and following arthroscopic procedures. Meniscus root repair has demonstrated good outcomes, and acute injuries with intact cartilage should be repaired. Cartilage degeneration, BMI, and malalignment are important considerations when choosing surgical candidates. Meniscus centralization has emerged as a viable adjunct strategy aimed at correcting meniscus extrusion.SummaryMeniscus root repair results in a decreased rate of OA and arthroplasty and is economically advantageous when compared with nonoperative treatment and partial meniscectomy. The transtibial pull-through technique with the addition of centralization for the medial meniscus is associated with encouraging early results.  相似文献   
44.
目的:比较关节镜辅助复位内固定(ARIF)和切开复位内固定(ORIF)治疗胫骨平台骨折的疗效。方法:回顾性分析2016年1月至2018年8月华中科技大学附属协和医院骨科收治的75例胫骨平台骨折患者的资料。男58例,女17例;年龄20~54岁,平均47岁。左侧42例,右侧33例。骨折根据Schatzker分型:Ⅰ型23例...  相似文献   
45.
目的通过对胫骨干骨折髓内钉内固定治疗后膝关节痛的临床观察,探讨膝关节痛的发生和病因。方法回顾研究1996年5月~2006年4月应用交锁髓内钉内固定治疗胫骨干骨折685例,所有病例在骨折愈合后均有1次以上的随访,平均随访时间为24.2个月。结果共有165例术后发生膝关节痛,经髌韧带入路组膝关节痛发生率为34.5%,髌韧带内侧入路组为14.6%,两组有显著性差异。结论髌韧带旁入路能减少胫骨干骨折髓内钉治疗术后膝关节痛的发生,建议使用髌韧带周围入路,髓内钉固定后膝关节痛的原因尚需进一步研究。  相似文献   
46.
目的:观察在复杂胫骨平台骨折手术治疗中使用三维重建结合3D打印技术的治疗效果。方法:选取2017年3月—2019年10月在廉江市人民医院接受复杂胫骨平台骨折手术的72例患者,按照随机分组法分为对照组与观察组,各36例。对照组应用常规手术治疗法,观察组应用三维重建结合3D打印技术。观察两组临床指标、膝关节功能及运动功能、并发症发生率。结果:治疗前,两组膝关节功能及运动功能评分对比无显著差异(P> 0.05);治疗后,观察组术中出血量、术中透视次数少于对照组,手术时间、住院时间及骨折愈合时间短于对照组,差异有统计学意义(P <0.05)。治疗后,观察组膝关节功能及运动功能评分均显著高于对照组(P <0.05)。观察组并发症发生率低于对照组,差异有统计学意义(P <0.05)。结论:在复杂胫骨平面骨折手术治疗中使用三维重建结合3D打印技术,有助于优化患者的手术指标,提升膝关节功能及运动功能,降低并发症发生率,手术效果显著。  相似文献   
47.
目的 总结赝复体联合组织间^125I放射性粒子植入术治疗腭部腺源性恶性肿瘤的护理经验.方法 对10例行赝复体联合组织间放射性粒子植入治疗的腭部腺源性恶性肿瘤患者的治疗及护理情况进行回顾性分析;术后随访观察患者的治疗效果及不良反应.结果 所有10例患者均顺利接受治疗,成功率100%;术后随访2~15个月,均未发现靶区覆盖范围肿瘤复发或转移;无并发症发生.结论 对腭部腺源性恶性肿瘤患者,手术切除后采用赝复体联合组织间放射性粒子植入进行放射治疗,近期效果较好,不良反应小.术前做好充分准备,术后加强生命体征监测及做好并发症的观察和护理,均有效地保证了此项技术的顺利开展.  相似文献   
48.
目的比较宁夏地区回族礼拜、不礼拜人群膝关节骨性关节炎(KOA)患者的病变程度在X线片上表现的差异,探讨回族KOA与礼拜的相关性。方法收集宁夏地区回族中老年人KOA患者290人456例膝,按是否礼拜分为礼拜组与非礼拜组。临床诊断采用美国风湿病学院推荐的临床标准,X线分级采用Kellgren和Lawrence提出的骨性关节炎X线分级修订标准。患者拍摄正位片及髌骨轴位片,测量股胫关节内、外侧间隙值、FTA角等指标,比较礼拜组与非礼拜组在X线片上的差异。结果礼拜组在膝关节间隙狭窄、内翻畸形的阳性率高于非礼拜组,X线分级程度大于非礼拜组,两组差异有统计学意义(P〈0.01)。髌股不稳指标测量,礼拜组的阳性率高于非礼拜组,两组差异有统计学意义(P〈0.01)。结论(1)宁夏地区回族礼拜人群KOA患者膝关节间隙狭窄、内翻畸形、髌骨不稳的程度都严重于非礼拜人群。(2)礼拜导致膝关节反复的应力负荷,加速KOA退行性变的程度。  相似文献   
49.
目的:探讨金-瓷修复体瓷裂或瓷崩的原因。方法:随机选择38例前牙和磨牙区因瓷裂或瓷崩而导致失败的病例,记录修复体损坏的部位。分析产生失败的原因。结果:瓷裂或瓷崩发生在前牙切缘或切角的病例数为8例(占21.05%),前牙舌(腭)侧为4例(占10.53%),前后牙颈缘为6例(占15.79%),后牙颊、舌(腭)面或功能尖11为例(占28.95%)后牙颊合面边缘为5例(占13.16%)后牙颊面为4例(占10.52%)。结论:金-瓷修复体损坏与临床设计、牙体制备及技术室制作有密切的关系。  相似文献   
50.
We performed a novel hydroxyapatite (HA) prosthesis implantation method in which an HA implant was implanted into the scleral shell with an autogenous scleral cap.Twenty-six patients who had undergone the novel HA prosthesis implantation method and 32 patients who had undergone traditional HA prosthesis implantation were retrospectively reviewed. The postoperative activity of the artificial eye was measured by the Hirschberg test combined with arc perimetry. The visual analog score (VAS) was used to evaluate 2-month postoperative pain and 2-month postoperative discomfort. HA implant vascularization was measured with enhanced magnetic resonance imaging (MRI) 2 and 6 months after the operation. The enhancement volume (VE) and the volume of the HA implant (VHA) were measured. All cases were followed up for 2 years. Measurement data were processed using SAS 6.12.There was a statistically significant difference (P = .016) between the percentages of excellent grade in the two groups. Two months after implantation, the median pain scores of the study and control groups were 2 and 2.5, respectively, and there was a statistically significant difference (W = 585.0, P = .004); there was a statistically significant difference (W = 535.5, P = .000) between the median discomfort scores of the study group (score = 1) and control group (score = 2); the mean VE/VHA values of the study and control groups were 0.3075 and 0.1535, respectively, and there was a statistically significant difference (t = −8.196, P = .000). Six months after implantation, the VE/VHA values of the study and control groups were 0.9686 and 0.5934, respectively, and there was a statistically significant difference (W = 549.0, P = .000). Within 2 years of postoperative follow-up, there were no serious complications in the study group.In the study group, in which the hydroxyapatite implant was implanted into a preserved scleral shell with unaltered muscles and covered with an autogenous scleral cap, postoperative activity and the fibrovascularization of the HA implant were significantly increased, and postoperative pain and discomfort were significantly reduced.  相似文献   
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