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1.
目的 探讨CAD/CAM技术联合个性化预成型钛网及游离髂骨移植修复单侧下颌骨大型轮廓缺损的可行性及有效性。方法 选取四川大学华西口腔医院正颌及关节外科2015年11月—2019年12月的15例单侧下颌骨大型轮廓缺损的患者。采用基于逆向工程的计算机辅助设计/计算机辅助制作(CAD/CAM)技术,镜像重建患侧下颌骨轮廓并制作个性化预成型钛网,术中切取游离髂骨联合预制钛网经颌下植入于下颌骨缺损部位,其中2例患者同期行颏成形术矫正颏部偏斜。术后通过测量比较双侧下颌支及下颌体的长度及其三维角度评价下颌骨轮廓的对称性。结果 所有患者预后良好,对手术效果满意且无不良并发症,术后三维测量结果显示下颌骨轮廓对称性良好(P>0.05)。结论 利用CAD/CAM技术制作个性化预成型钛网联合髂骨移植修复单侧下颌骨大型轮廓缺损可行,效果良好。  相似文献   
2.
【摘要】目的:评估3D打印人工椎体与传统钛笼在颈椎前路椎体次全切除减压植骨融合术(anterior cervical corpectomy and fusion,ACCF)中应用的临床效果。方法:回顾性分析2017年6月~2020年6月于承德医学院附属医院脊柱外科行单椎体ACCF的50例脊髓型颈椎病患者,其中25例术中应用3D打印人工椎体(观察组),25例术中应用传统钛笼植骨(对照组)。记录两组患者手术时间、术中出血量、C型臂X线机透视次数及随访时间。术前、术后3天、术后3个月及末次随访时在颈椎侧位X线片上测量椎体次全切除节段椎间高度(H1、H2)、C2-7 Cobb角、C2-7矢状面轴向距离(C2-7 sagittal vertical axis,C2-7 SVA)及T1倾斜角,比较两组患者各时间点的影像学参数;应用日本骨科协会(Japanese Orthopaedic Association,JOA)评分评价神经功能,应用疼痛视觉模拟(visual analogue scale,VAS)评分评价颈部疼痛。根据Kandziora标准判断植骨融合情况。结果:所有患者均获得随访,观察组随访时间12~33个月(24.16±4.95个月);对照组随访时间12~33个月(22.60±5.91个月),两组患者随访时间比较无统计学差异(P>0.05)。两组患者手术时间、术中出血量和C型臂X线机透视次数均无显著性差异(P>0.05);两组患者术后各时间点的JOA评分和VAS评分较术前均有明显改善,差异均有统计学意义(P<0.05),两组间同时间点比较无统计学差异(P>0.05);术后两组患者各时间点的椎体间高度、C2-7 Cobb角、C2-7 SVA及T1倾斜角与术前相比均有明显改善(P<0.05),两组间术前及术后3天比较无显著性差异(P>0.05),术后3个月及末次随访时两组间比较有统计学差异(P<0.05)。末次随访时观察组19例人工椎体存在下沉,下沉距离为0.1~0.9mm,无严重下沉患者;对照组20例钛笼下沉,下沉距离为1.3~3.5mm,有4例严重下沉患者;观察组人工椎体下沉距离小于对照组钛笼下沉距离,差异有统计学意义(P<0.05)。末次随访所有患者均实现骨性融合。结论:脊髓型颈椎病患者行ACCF时应用3D打印人工椎体和传统钛笼植骨均可恢复椎体间高度,重建颈椎稳定性及颈椎生理曲度;3D打印人工椎体能够减缓术后支撑假体的沉降,进而维持减压椎体间高度。  相似文献   
3.
目的 探讨微弧氧化(MAO)表面改性3D打印多孔钛合金支撑棒对羊距骨坏死的治疗作用,为其进一步临床应用提供基础。方法 观察3D打印多孔钛合金支撑棒通过MAO表面改性后,其表面形态、元素变化及晶像情况。通过体外细胞实验,研究大鼠成骨细胞在材料表面的黏附、增殖及分化情况。建立羊距骨坏死模型基础,并置入3D打印多孔钛合金支撑棒,探究其在距骨内的稳定性及其成骨修复情况。结果 通过MAO改性,材料表面形成大小均一的多孔微米结构,Ca、P、O元素分布在材料表面,同时表面形成TiO2晶像。在体外细胞实验中,MAO改性组和对照组均表现出良好的生物相容性,但是MAO改性组在细胞接种后8 h黏附能力优于对照组、接种1、4、7 d后细胞增殖能力均优于对照组,同时接种7 d时细胞分化能力也优于对照组,差异具有统计学意义(P<0.05)。羊距骨植入实验表明,术后12周两组支撑棒都有骨长入,但是MAO改性组与对照组相比其周围有更多的新生骨长入。定量结果显示MAO组的骨体积分数、骨小梁厚度也优于对照组,差异具有统计学意义(P<0.05)。结论 仿生的3D打印多孔结构为支撑棒提供了优良的力学性能,MAO表面改性进一步提高了其生物活性,使其在治疗羊距骨早期骨坏死过程中充分发挥了力学和生物学的优势。本临床前研究效果满意,并为其未来临床应用提供了理论和研究基础。  相似文献   
4.
The endodontic literature contains a plethora of studies on static and dynamic cyclic fatigue resistance tests performed on a large array of rotary or reciprocating nickel–titanium endodontic instruments. It was the aim of this review to summarize the currently available evidence to point out the different outcomes from static versus dynamic tests and to assess whether cyclic fatigue tests provide useful data and information for clinical practice. An electronic literature research in the database PubMed was performed using appropriate search terms, and the titles and abstract were screened for relevance. Language was restricted to English. The review reveals marked differences between the results obtained in static and dynamic tests, and also, the results for the same instruments assessed either under static or dynamic experimental conditions are widely inconsistent. Between the lowest and the highest value for one and the same pathfinding instrument was a factor of about 123 when cyclic fatigue was assessed either under static or dynamic experimental conditions. Moreover, standard deviations of up to 30% have been reported. Environmental temperature has a 500% impact on the lifetime of instruments. In conclusion, fatigue resistance tests conducted under room temperature should be regarded as having little meaning and the scientific and clinical benefits of fatigue resistance tests are very limited. These data should be provided by the manufacturer of the instruments.  相似文献   
5.
6.
Although stapler dissection and closure is commonly used for laparoscopic distal pancreatectomy (LDP), it is risky in patients with thick pancreatic parenchyma or titanium allergy. We performed laparoscopic pancreatic parenchymal dissection with cavitron ultrasonic surgical aspirator (CUSA) successfully in a patient with titanium allergy. Slinging the pancreas with nylon tape delineates the surgical plane. Pancreatic parenchyma was transected by CUSA in an almost bloodless field. Pancreatic duct branches and vessels were adequately exposed and dissected with a vessel sealing system. The main pancreatic duct was closed with Hem-O-lock. CUSA is an alternative to stapler dissection during LDP in select patients.  相似文献   
7.
【摘要】目的:分析保乳术后放疗患者钛夹动度,并探讨其与乳腺大小、钛夹位置的相关性。方法:随机选取保乳术后放疗患者15例,每周两次锥形束CT。测量乳腺基底面直径(D)和乳高轴(H),以瘤床质心为原点将临床靶区分4个象限。记录各象限内钛夹在左右、腹背、头脚方向动度(MLR、MAP、MSI)以及其与临床靶区最内、最前、最上的距离(DSLR、DSAP、DSSI)。结果:MLR、MAP、MSI分别为(2.2±3.0)、(-1.1±3.6)、(0.8±4.7) mm;系统误差Σ在左、右、腹、背、头、脚分别为1.7、2.2、2.0、2.4、2.9、3.0 mm,随机误差σ分别为2.4、4.0、3.2、4.0、4.7、4.7 mm;靶区对应外放5.9、8.3、7.2、8.8、10.5、10.9 mm。一象限内,当D×H<99.89 cm2,MAP和D×H强相关(r=0.805),MLR、MAP均和DSLR、DSAP、DSSI强正相关(r=0.94, 0.94, 0.91;0.87, 0.91, 0.92),MSI和DSLR、DSAP强正相关(r=0.91, 0.94);四象限内,当D×H<90.71 cm2,MAP和DSLR,MSI和DSAP均强负相关(r=-0.96;-0.95),MLR和DSLR强正相关(r=0.91)。结论:钛夹动度有各向异性,以SI方向外扩最大,并易受乳腺大小、钛夹位置影响。  相似文献   
8.
(1) It is estimated that 10% of the world’s population will need a dental implant in their lifetime. Despite all the advances in the comprehension of dental implant designs, materials and techniques, traditional implants still have many limitations. Customized root-analogue implants are, therefore, gaining increased interest in dental rehabilitation and are expected to not only preserve more hard and soft tissues but also avoid a second surgery and improve patient overall satisfaction. In this sense, the aim of this review was to collect and analyse the clinical trials and case reports on customized root-analogue implants available in the literature; (2) This review was carried out according to the PRISMA Statement. An electronic database search was performed using five databases: PubMed, Google Scholar, Medline, Science Direct, and Scopus. The following keywords were used for gathering data: custom-made, dental implants, root-analogue, anatomical, customized and tooth-like; (3) 15 articles meeting the inclusion criteria—articles reporting clinical trials, case reports or animal studies and articles with root-analogue implants and articles with totally customized implant geometries—were selected for the qualitative synthesis. The design and manufacturing techniques, implant material and surface treatments were assessed and discussed; (4) The performance of some root-analogue implants with specific features (i.e., macro-retentions) was successful, with no signs of infection, periodontitis nor bleeding during the follow-up periods.  相似文献   
9.
Reconstruction of the facial skeleton is challenging for surgeons because of difficulties in proper shape restoration and maintenance of the proper long-term effect. ZrO2 implant application can be a solution with many advantages (e.g., osseointegration, stability, and radio-opaqueness) and lacks the disadvantages of other biomaterials (e.g., metalosis, radiotransparency, and no osseointegration) or autologous bone (e.g., morbidity, resorption, and low accuracy). We aimed to evaluate the possibility of using ZrO2 implants as a new application of this material for craniofacial bone defect reconstruction. First, osteoblast (skeleton-related cell) cytotoxicity and genotoxicity were determined in vitro by comparing ZrO2 implants and alumina particle air-abraded ZrO2 implants to the following: 1. a titanium alloy (standard material); 2. ultrahigh-molecular-weight polyethylene (a modern material used in orbital surgery); 3. a negative control (minimally cytotoxic or genotoxic agent action); 4. a positive control (maximally cytotoxic or genotoxic agent action). Next, 14 custom in vivo clinical ZrO2 implants were manufactured for post-traumatologic periorbital region reconstruction. The soft tissue position improvement in photogrammetry was recorded, and clinical follow-up was conducted at least 6 years postoperatively. All the investigated materials revealed no cytotoxicity. Alumina particle air-abraded ZrO2 implants showed genotoxicity compared to those without subjection to air abrasion ZrO2, which were not genotoxic. The 6-month and 6- to 8-year clinical results were aesthetic and stable. Skeleton reconstructions using osseointegrated, radio-opaque, personalized implants comprising ZrO2 material are the next option for craniofacial surgery.  相似文献   
10.
目的探讨内镜下金属钛夹止血联合黏膜下注射肾上腺素治疗溃疡性上消化道出血(UGIB)的效果及对氧化应激指标的影响。方法将2016年5月至2020年5月住院治疗的86例溃疡性UGIB患者按随机抽签法分为对照组与观察组,每组43例。对照组于内镜下黏膜下注射肾上腺素,观察组在对照组基础上联合内镜下金属钛夹止血,比较两组的治疗效果。结果观察组的治疗总有效率高于对照组(P<0.05)。观察组的止血时间、大便潜血转阴时间、住院时间短于对照组(P<0.05)。治疗后,观察组的AOPP、MDA、血管升压素水平低于对照组(P<0.05)。观察组的不良反应总发生率低于对照组(P<0.05)。结论内镜下金属钛夹止血联合黏膜下注射肾上腺素治疗溃疡性UGIB可获得理想的止血效果,缩短止血时间,改善患者氧化应激指标,安全可靠。  相似文献   
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