电磁场对商业纯钛种植体周围骨愈合影响的组织学和力学研究

脉冲电磁场(PEMF)已成功用于治疗骨科中的假关节病和不愈合性骨折。一些研究提示：在口腔种植手术后运用脉冲电磁场治疗有利于种植体周围骨愈合。有关PEMF促进骨愈合的机制还未完全阐明，但认为PEMF能促进组织血管化、胶原生成和骨原细胞的增殖分化。迄今为止，几乎所有     

改良喷砂钛种植体表面加快骨愈合的细胞学研究

目的　体外研究改良喷砂表面对成骨细胞功能、分化的影响 ,从细胞水平揭示该表面促进骨愈合的作用机制。方法　成骨细胞为原代分离、培养的第 5代人胚成骨细胞 ,选择细胞层碱性磷酸酶 (alkalinephosphatase,ALP)活性、蛋白质含量以及培养液中骨钙素含量作为评价成骨细胞功能、分化的 3项指标。采用酶动力法检测ALP活性、采用考马斯亮蓝法测定蛋白质含量、采用放免测定技术检测骨钙素含量 ,所得各值进行标准化处理。实验分 3组 :改良喷砂表面组、光滑表面组和细胞培养板空白对照组 ,细胞培养取 4d和 1 3d两个时间点。结果　细胞培养 4d ,改良喷砂表面组细胞层ALP活性 [(1 7 390± 1 59)nmolPNP·min- 1 ·1 0 - 6 个细胞 ]、蛋白质含量 [(1 52 7± 1 6 3) μg/1 0 6个细胞 ]以及培养液中骨钙素含量 [(43 0± 6 1 )ng/1 0 6 个细胞 ]均明显高于光滑表面组 [分别为(1 0 978± 1 879)nmolPNP·min- 1 ·1 0 - 6 个细胞、(58 0± 5 9) μg/1 0 6 个细胞及 (2 4 9± 6 0 )ng/1 0 6 个细胞 ]。培养至 1 3d ,各项指标两组间差异消失。结论　从细胞学角度证明改良喷砂表面具有加快种植体骨愈合的作用 ,该作用是通过促进成骨细胞分化和功能表达实现的     

增龄变化对钛种植体骨结合影响的实验研究

目的探讨增龄变化对钛种植体骨结合的影响，为临床判断种植预后提供理论依据。方法选择雄性SD大鼠36只，随机分成青年群、成年群和老年群，在双侧胫骨内侧窝距关节0．5cm处分别植入钛种植体2颗。三组大鼠分别在术后14天、28天、56天随机各处死4只，摘取胫骨，制作带种植体的非脱钙硬组织切片，观察组织学变化，计算骨结合率。结果青年群的成骨能力最强，种植体与骨的结合连续、紧密，成年群次之，老年群最差。老年群成骨量及骨接触率均低于青年群和成年群。以上情况对松质骨影响大，对皮质骨影响小。结论增龄变化可影响钛种植体与骨组织的结合，种植体周围新骨形成量及骨结合率随年龄增长而降低。     

低功率He：Ne激光促进种植体骨结合的实验研究

目的：探讨低功率He：Ne激光照射能否增加种植体骨结合率。方法：选取6只Beagle犬,于每只犬每侧胫骨植入3枚种植体,将每只犬的6颗种植体随机编入A、B、C组,A组设为对照组,B、C组术后立即采用低功率He：Ne激光照射,B组持续照射1周,C组持续照射2周。术后4、8、12周每次处死2只动物,取材制作非脱钙骨磨片,进行骨形态计量学分析,比较各组新骨形成状况,计算每颗种植体骨结合率并作统计学处理。结果：每个检测期A、B、C组种植体骨结合率均有显著差异（P〈0.01）,均表现为：C组（B组（A组。结论：低功率He：Ne激光照射能显著增加种植体骨结合率,连续照射2周较1周效果好。     

不同功率He:Ne激光对种植体骨结合面积影响的动物实验研究

目的:探索不同功率He:Ne激光对种植体骨结合面积的影响。方法:选取成年雄性Beagle犬6只,每只犬每侧胫骨植入4枚种植体,种植体随机编入A、B、C、D组,A、B、C组为实验组,D组为对照组,每组12枚,共48枚。实验组术后立即采用不同功率He:Ne激光垂直照射种植体对应体表,A组15.9J/cm2、B组26.5J/cm2、C组37.1J/cm2,20min/次,1次/d,持续2周。术后1、2、3个月分别处死2只犬,取标本制作种植体骨磨片,Goldner’s三色法染色后测量种植体骨接触率,所得数据采用统计学处理。结果:种植体骨接触率:术后1、2个月A、B、C、D组间无显著差异,术后3个月A与B及C与D组间无显著差异,A、B组明显高于C、D组(P<0.05)。结论:术后持续照射低功率He:Ne激光2周,能明显增加种植体骨结合的面积,以15.9J/cm2或26.5J/cm2照射效果最佳。     

羟基磷灰石烧结涂层种植体和纯钛种植体的对比实验研究

将相同大小的ＨＡ１涂层种植体（涂层烧结温度８５０℃）、ＨＡ２涂层种植体（涂层烧结温度１０５０℃）和Ｔｉ种植体植入狗股骨１、３、６个月，行界面形态学，定量组织学及生物力学测试，结果发现：１、Ｔｉ种植体和涂层种植体均具有良好的生物相容性，能和骨组织形成良好的骨性结合，其中涂层种植体能在种植早期加速界面骨性结合的形成，界面强度高于纯钛。涂层种植体一骨组织界面受剪切破坏后，断裂面在涂层材料内，而Ｔｉ种植体     

表面氧化处理钛种植体—骨界面动物实验观察

为了确定氧化钛种植体的愈合过程 ,作者将氧化钛种植体作为研究对象 ,羟基磷灰石涂层种植体作为对照 ,将种植体植入成犬股骨中 ,在术后 1月、2月、3月、4月处死动物 ,通过扫描电镜观察标本 .结果发现 :在种植后 1月 ,HA涂层的种植体与骨组织已有较好的初期愈合 ,氧化钛材料的初期骨组织愈合不如 HA涂层的种植体 ,在4个月的标本中 ,氧化钛涂层的种植体与 HA涂层的种植体无明显差异 ,均达到良好的骨性结合 .     

影响纯钛种植体骨整合界面形成的临床因素分析

目的 通过临床实践探讨影响钝钛种植体骨整合界面形成的因素,寻求防治措施,提高种植义齿的成功率。方法 对230例门诊种植病人采用Branemark纯钛种植体行延期种植术,3～6个月后行Ⅱ期手术。结合X线及术中所见,评价钝钛种植体骨整合界面形成状况。结果 在植入的520颗纯钛种植体中,获得骨整合界面的有503颗,失败17颗,成功率96.7%。结论 影响纯钛种植体骨整合界面形成的因素有术前严格选择适应证及充分的术前准备,防止骨灼烧,预防感染,防止术中种植体被污染。     

钛种植体-骨间隙愈合界面成骨方式的激光共聚焦显微镜观察

目的：观察钛种植体一骨界面的新生骨形成情况,探讨在间隙愈合模型中种植体和骨表面是否存在双向成骨现象。方法：将4枚带有环形凹槽的纯钛种植体经喷砂、酸蚀处理后,植入兔股骨远端髁突内。术后第5d和第19d分别肌肉注射钙黄绿素和茜素红。采用激光共聚焦显微镜观察带种植体的硬组织切片。结果：激光共聚焦显微镜显示,种植体的间隙区域均有新生骨组织生成。在间隙区域,骨创面和相应的种植体表面分别存在绿色荧光带（钙黄绿素）,二者问不连续,而在19d时注射的茜素红所标记的红色荧光将二者连接融合,并可见大量红色荧光分布于绿色荧光周围。结论：种植体一骨界面存在远端成骨和接触成骨2种成骨方式,二者相向成骨。     

钛种植体复合硫酸软骨素A对骨愈合的影响

目的：研究钛种植体表面复合硫酸软骨素A(chondroitin sulfate-A，CS—A)后能否促进骨的愈合。方法：将钛种植体表面经钙处理及CS—A吸附处理后植入狗的股骨，分别在第15、30、60、120天对种植体周围骨愈合区域作X线、HE染色、四环素荧光标记显微法、扫描电镜观察及转移生长因子β1(transforming growth factor—β1，TGF-β1)免疫组化染色等方法检查分析。结果：与对照组相比，吸附了CS—A的钛种植体周围早期即有新骨形成，TGF-β1的早期表达活跃。结论：钛种植体复合CS-A后能促进成骨细胞的分化，加速种植体周骨质的矿化。     

复合牛骨形成蛋白多孔中空种植体成骨效应的研究

目的　利用激光扫描共聚焦显微镜(LSCM)观察牛骨形成蛋白复合种植体成骨效应。方法　将天然提取的牛骨形成蛋白(bBMP)与多孔中空钛种植体相复合形成人工复合种植体,植入狗下颌骨,并设同等规格的实心柱状钛种植体及不复合bBMP的多孔中空柱状钛种植体植入狗下颌骨为对照组。应用三色荧光标记LSCM观察复合种植体周围骨整合情况。结果　实验组复合种植体在各时期成骨能力和成骨量均明显优于对照组。结论　复合种植体可诱导早期、大量、较持久的成骨;LSCM对种植体周围成骨行为进行观察是一种准确、有效的手段。     

Effects of Implant Design and Surface on Bone Regeneration and Implant Stability: An Experimental Study in the Dog Mandible

Background: Previous experimental studies have shown a higher degree of bone‐implant contact for surface‐enlarged implants compared with machined implants. Yet, there is insufficient evidence that such implants show higher stability and an increased survival rate. Purpose: The purpose of this investigation was to study the integration and stability of grit‐blasted implants with retention elements on the implant neck, with and without marginal bone defects, compared with machined implants without retention elements. Materials and Methods: After tooth extraction of the mandibular premolars in six dogs, two grit‐blasted, partly microthreaded Astra Tech implants and one standard Branemark implant were bilaterally placed in each dog. On one side, 3 ± 3 mm large buccal defects were created, to expose three to four implant threads. The contralateral side served as control, and no defects were made. The animals were sacrificed after 4 months of healing. Implant stability was measured using resonance frequency analysis at implant installation and after 4 months of healing. Histologic and histomorpho‐metric evaluation was made after 4 months of healing. Results: Resonance frequency analysis indicated that all implants in the test and control groups were osseointegrated after 4 months, with a tendency toward higher implant stability for the Astra Tech implants. There was a statistically significant higher increase in resonance frequency for the Astra test implants compared with their corresponding controls. Histology and histomorphometry showed well‐integrated implants with varying degrees of bone repair at the defect sites. The greater bone‐implant contact for the Astra implants was statistically significant. No significant difference between the implants in amount of bone filling the threads was recorded. Conclusions: The Astra Tech implants tested showed a higher degree of bone—implant contact and higher level of bone regenerated at defect sites compared with the Brånemark implants. Resonance frequency analysis demonstrated a significantly higher increase in the Astra test implants compared with their control groups than did the Brånemark test implants versus their controls.     

骨收集器收集自体骨充填种植体周围骨缺损的实验研究

目的:研究利用植入钻孔时骨收集器收集的骨碎末修复种植体周围骨缺损的可行性。方法:以5只家犬双侧下颌骨为实验对象,拔除双侧各3颗前磨牙3月后,行种植术,每侧植入4颗种植钉。种植时人为造成种植体颊侧2mm×2mm大小骨缺损,在同体同侧的4个骨缺损中的3个,分别植入自体骨屑、Bio-Oss骨粉、二者1∶1混合骨末,剩余1处不植入任何材料作为对照。9周后进行各组间比较。结果:植入的自体骨碎屑修复了一定的骨缺损,自体骨混合Bio-Oss组骨缺损恢复最佳。各组与对照组比较均存在统计学差异。结论:植入钻孔时收集的自体骨碎屑对于修复种植体周围少量的骨缺损,是完全可行的。当供骨量不足时,自体骨碎末可以混合适当的Bio-Oss颗粒植入,效果更为理想。     

种植体与骨组织界面活体生物力学实验研究

为了对种植体与骨组织界面进行有关的生物力学研究，本实验采用树脂-羟磷灰石复合材料制成牙根状种植体，手术植入狗下颌牙槽窝内。植入木后1、2、4、8周，采用应变电测法活体测量种植体处颌骨表面的应变值。结果是随着植入时间增加，所测得的种植体处颌骨表面的应变值也相应增加。这提示了种植体与骨组织界面对压力的传导性在不断增强。结论：在种植早期，具有良好生物相容性的种植体与骨界面的骨结合强度随时间性(time-mather)在不断地增加。     

种植术后放疗对兔胫骨种植体骨结合影响的实验研究

目的:探讨种植术后放疗对种植体周围骨密度、种植体骨结合的影响。方法:在16只日本大白兔双侧后肢胫骨同一位置各植入纯钛种植体1枚,2周后随机选取8只作为放疗组,一次性给予60Co15Gy剂量的放疗,余下8只作为对照组不接受放射治疗。通过大体观察、双能X线分析、组织形态学、骨计量学分析及骨-种植体磨片观察等手段,研究术后4、8、16、24周时种植体骨结合情况,应用F检验对实验结果进行统计学分析。结果:术后4周时放疗组种植体周围骨密度比未放疗组降低(P<0.05),种植体骨结合率也较未放疗组降低;术后8周时放疗组种植体周围出现明显的骨结合现象,相当于未放疗组术后4周时的水平;术后16周以后放疗组与未放疗组种植体周围骨密度及种植体骨结合率的差异无显著性。结论:放疗可在一段时间内延缓种植体周围骨的生长,降低骨种植体结合率。     

Relationship between Systemic Bone Mineral Density and Local Bone Quality as Effectors of Dental Implant Survival

Purpose: This study aimed to assess (1) the relationship of systemic bone mineral density (BMD) and osteoporotic status with the surgeon's subjective assessment of local jawbone quality, and (2) whether the surgeon's subjective assessment of local jawbone quality is a predictor of implant failure. Materials and Methods: A retrospective analysis of 2,867 dental implants placed in 645 patients was accomplished. The surgeon's assessment of bone quality at the time of dental implant placement was recorded. Of those, 208 patients with 701 implants had BMD data available within 3 years. Statistical analyses were conducted to determine relationships between BMD, osteoporotic status, and local jawbone quality and to determine the relationship between local jawbone quality and implant survival. Results: There was no association between systemic BMD and the surgeon's assessment of bone quality (p = .52) nor between osteoporotic status and the surgeon's assessment of local jawbone quality (Spearman rank correlation coefficient = 0.08). Additional retrospective analysis revealed implants placed in moderate‐ (hazard ratio = 1.67; p = .043) or poor‐quality (HR = 3.45, p < .001) bone (surgeon's assessment) were significantly more likely to fail than implants placed in good‐quality bone. Conclusion: Systemic BMD and osteoporotic status are not associated with local jawbone quality. Implants placed in good‐quality bone, as assessed subjectively by the surgeon at the time of implant placement, have significantly better survival characteristics than implants placed in moderate‐/poor‐quality bone.     

纯钛膜结合自体骨修复种植牙美观区骨缺损的临床研究

目的：评价无孔纯钛膜结合自体碎骨整复种植牙美观区骨缺损的临床效果,并探讨其临床应用技巧.方法：8例前牙美观区缺失伴唇颊侧牙槽骨凹陷畸形要求种植修复患者,采用自体碎骨屑移植充填骨缺损区,无孔纯钛膜覆盖治疗,共计植入种植体19枚.术后6个月行种植Ⅱ期手术,同时取出钛膜.结果：除一例术后1月局部钛膜暴露外,余软组织瓣均愈合良好,术后6个月骨缺损区呈完全骨性修复.结论：纯钛膜具有良好的生物相容性,能有效地防止自体移植碎骨移位、纤维结缔组织长入,其塑形性好,能维持较大的骨再生修复空间.