VEGF和TGF-β1促进非血管化骨移植同期种植骨结合的实验研究

目的:探讨外源性VEGF和TGF-β1对非血管化骨移植同期种植的影响。方法:选用实验犬24只(术前1个月拔除双侧下颌前磨牙),随机分为A、B 2组。选取左侧下颌骨造成2.5 cm全层骨缺损,植入同样大小的全层自体髂骨,钛板固定(髂骨块离体时间控制在20 min以内)。A组(12只)移植髂骨块内植入1枚钛种植体。B组(12只)将钛种植体与rhVEGF165和rhTGF-β1复合后再同法植入移植髂骨内。在所有实验犬的右侧下颌无牙区植入1枚种植体作为对照。术后1、2、4个月取材,行X线、组织学、显微CT观察和种植体骨结合力测试。结果:术后1、2个月B组种植体骨接触率较A组显著增高;对种植体周围骨小梁的显微CT分析表明,B组的成骨的作用较A组明显增强。术后4个月,A、B 2组BIC达到60%以上,种植体骨界面结合力接近220 N,已形成较好的骨结合。结论:VEGF和TGF-β1对NVBG同期种植体骨结合早期(术后1～2个月)有明显的促进作用。NVBG同期种植体在术后4个月可以进行上部义齿修复。     

离体时间对非血管化游离骨移植同期种植体骨内固位影响的实验观察

目的：研究非血管化游离骨移植同期种植的种植体固位力与游离骨块离体时间的关系,判断游离骨块离体时间对其存活和成骨的影响。方法：16只实验犬分为A、B两组,A组为非血管化游离骨块离体30min组;B组为非血管化游离骨块离体90min组。制作下颌骨节段性缺损的动物模型,取与缺损大小相当的自体非血管化全层游离髂骨,分别在30 min和90 min内植入纯钛金属种植体,用于修复下颌骨缺损处,牢固内固定。手术当时和术后3d、1周、2周、4周测量从骨内拉出种植体所用力的大小。HE和三色染色观察植骨块内骨成活和骨质变化状况。结果：A组,在种植体植入当时和骨移植后3d、1周、2周、4周各时间点,拔出种植体的力分别为144±13 N、140±15 N、134±9 N、137±13 N、146±7 N;骨块未见明显吸收,组织切片HE染色,骨块中央部位的骨陷窝内可见骨细胞,骨块中央部位可见成形骨小梁,部分骨陷窝空虚,但破骨现象不明显。改良Mallory染色,部分区域的骨密度有降低。B组在骨移植后3 d、1周、2周、4周,拔出种植体的力分别为143±14 N、140±7 N、133±11 N、130±7 N、136±2 N;骨块部分区域可见明显吸收,见到破骨细胞及明确的破骨现象;较多的骨陷窝空虚,成活的骨细胞较少,部分骨小梁有密度减低现象。结论：非血管化游离骨块的离体时间与移植后的骨成活密切相关,也就影响到了种植体的骨结合,因此,在临床应用时应尽量缩短非血管化游离骨的离体时间,以减少移植后的骨吸收。     

血管化与非血管化移植骨同期种植的比较研究

采用Branemark种植技术，对双侧下颌骨体部大部切除患者同时行血管化和非血管化骨移植，同期植入种植体。本文就VBC和NVBG与种植体之间的骨结合及两种不同移植骨之间骨结构进行了比较研究。     

骨移植牙种植体同期植入的扫描电镜观察

目的：探讨骨移植牙种植体同期植入后骨整合的效果。方法：恒河猴6只随机分三组分别行血管吻合骨移植（Vascularized Bone Graft,VBG)牙种植体同期植入；游离骨移植（Non-Vascularized Bone Graft,NVBG)牙种植体同期植入，拔牙后三个月植入牙种植体，切取标本后扫描电镜观察，结果：VBG组：术后12周移植骨与种植体之间部分为骨性结合界面，16周呈完整的骨性结合，NVBG组：术后12周其界面为纤维结缔组织，少量骨少梁，24周大部分为骨性结合界面，呈完整的骨性结合。结论：VBG或NVBG牙种植体同期植入均能形成骨性整合，但NVBG组形成较晚，临床应用中应予注意。     

非血管化骨-人重组骨形成蛋白-2复合种植体同期移植的超微结构观察

目的对于非血管化自体骨移植同期植入种植体,目前仍有争议.近年的研究表明非血管化自体骨植入后,早期即可有新骨形成.本研究旨在探讨非血管化自体骨-种植体同期植入后种植体的愈合过程,并观察骨形成蛋白对与非血管化骨同期植入的种植体愈合过程的促进作用.方法健康犬12只,随机分为2组.在犬双侧下颌角区各截取3cm×4cm骨段,实验组骨段内植入含有重组人骨形成蛋白-2的种植体,对照组植入普通纯钛种植体.植入种植体后,将骨块及种植体植回对侧下颌角,并以不锈钢丝固定.术后2、4、6、8及12周各处死2只动物,标本行扫描电子显微镜观察.结果实验组种植体-骨界面在术后2周即可见明显的新骨形成,术后6～8周,已基本形成骨性结合;术后12周时,可见较为成熟的骨融合.而对照组骨融合在术后6～8周方开始形成,术后12周时仍未完成.实验结果显示,实验组骨融合的时间较对照组至少可提前4周.结论骨形成蛋白的骨诱导活性可以促使种植体在植入后早期与非血管化骨形成骨融合,从而为提高同期植入种植体的成功率提供了新的途径.     

非血管化游离骨移植同期种植骨活力的实验研究

目的观察非血管化骨移植同期种植的骨块在不同离体时间点植入体内后细胞活力及成骨情况.方法拔除狗前磨牙,口腔粘膜完全愈合后,截除长度3 cm的无牙下颌骨段,取不带血管和软组织的髂骨全层,植入直径2 mm带自攻螺纹的纯钛种植体2～3枚,分别在离体60、120分钟内植入下颌缺损区.术后4、8周取出植骨块,观察游离移植的非血管化骨块内细胞活力和新骨形成情况.结果非血管化游离骨移植同期种植恢复了下颌骨节段性缺损的连续性.游离骨块在离体60分钟植入体内4～8周为活骨块,可见到大量成活的骨细胞,并有数量不等的新骨形成.离体120分钟的游离骨块植入体内后4～8周为死骨块,其中未见成活骨细胞,部分骨块中见到破骨细胞.结论在以狗为对象的实验中,非血管化游离髂骨块移植同期种植可以修复长度3cm的下颌骨节段性缺损,植入体内骨块能否成活与其离体时间有关.     

纯钛种植体与非血管化髂骨骨结合的组织学观察

目的：研究纯钛种植体和非血管化髂骨块的骨结合情况。方法：10只杂种犬被随机分成5组，分别切取两侧游离髂骨移植于对侧，移植骨内同时植入钛种植体，术后不同时间点取材，组织学观察。结果：3周时，移植骨以吸收和坏死为主，6周时有新骨形成，9周时新骨形成的数量增加，12周时移植的骨块成活，骨组织改建完成，植入的钛种植体和移植的髂骨块之间无软组织介入，标志种植体与移植骨之间骨结合完成。结论：在本实验条件下，钛种植体和非血管化髂骨块可以形成完全骨结合。     

与非血管化骨同期移植的BMP-钛复合种植体的愈合过程观察

目的：探讨BMP-钛复合种植体与非血管化自体骨同期移植后种植体界面的愈合过程及BMP对界面骨融合过程的促进作用。方法：在犬前磨牙区截骨并原位回植，造成非血管化骨移植的动物模型，分别同期植入BMP-钛复合种植体及普通种植体。对术后不同时段的种植体界面进行硬组织切片甲苯胺蓝染色观察。结果：BMP-钛复合种植体植入后2周．界面即可见新骨生成．12周时骨融合基本完成。对照组骨融合过程较实验组延迟4周以上。结论：BMP-钛复合种植体的应用，可使种植体一移植骨界面的骨融合时间明显提前，从而缩短程，提高治疗的成功率。     

非血管化髂骨和下颌骨与钛种植体结合的比较研究

目的 :研究非血管化髂骨和下颌骨与钛种植体结合的组织学特点。方法 :12只杂种犬随机分为 6组。切取 15mm× 5mm的下颌骨骨质 ,将骨块移植于对侧下颌骨人工骨缺损区 ,然后切取同样大小的髂骨骨块 ,移植于下颌骨骨缺损区 ,同时植入 2枚钛种植体 ,用种植体固定骨块。术后不同时间点取材 ,组织学观察。结果 :髂骨移植后早期以溶解坏死为主 ,6周时开始重建 ,种植体为混合界面 ;12周时改建基本完成 ,种植体形成骨结合。而下颌骨移植后早期移植骨吸收不明显 ,只是哈佛氏管扩大 ,与种植体界面间未见新骨形成 ;12周时移植骨内出现新生骨 ,骨吸收停止 ,种植体为混合界面 ,界面有不成熟的新生骨沉积 ,新骨与原骨结合不紧。 18周 ,种植体形成骨结合。 2 4周 ,移植的髂骨和下颌骨与骨床均融为一体 ,下颌骨与髂骨相比整体致密。结论 :髂骨与下颌骨移植后的修复过程及它们与钛种植体的骨结合过程不同 ,但均能形成骨性结合。下颌骨与种植体形成骨结合的时间比髂骨长     

高压氧影响游离植骨种植体骨整合的组织学研究

目的：探讨高压氧能否促进种植体在非血管化新鲜自体游离移植骨上形成骨整合。方法：选用４只杂种成年狗,随机分成２组,每组２只,在狗下颌骨下缘各截取４ｃｍ×１．５ｃｍ大小的方形骨块,完全游离后原位植入,在植骨块上种入２个ＨＡ种植体。实验组动物在术后第 ３天开始进行高压氧（ＨＢＯ）治疗（２４．２ ｋＰａ、１．５ｈ／ｄ、５ｄ／周,共 ４周）,术后１０周处死 ４只动物,取含种植体的骨块,脱钙后腊包埋、切片、ＨＥ染色、组织学观察。结果：ＨＢＯ组种植体在移植骨上形成骨整合,种植体周围的新骨呈连续的骨界面。非ＨＢＯ组种植体界面呈不连续的新骨界面。结论：羟基磷灰石涂层种植体可在非血管化自体游离移植骨上形成骨整合,ＨＢＯ可以促进骨结合的形成。     

The Effect of a Constant Electrical Field on Osseointegration after Immediate Implantation in Dog Mandibles: A Preliminary Study

PURPOSE: The long time span between insertion of implants and functional rehabilitation often inconveniences patients. Accelerating bone growth around dental implants can shorten this time span. This in vivo study evaluated the effect of a constant electrical field on bone growth around dental implants. MATERIALS AND METHODS: Four mongrel dogs were used in this study. Sixteen dental implants were placed immediately after extraction of the first premolar and molar teeth. A constant electrical field (CEF) generator was placed in the mucoperiostal pouch created from the subperiostral dissection under the inferior border of the dog's mandible and connected to the experiment side fixtures. CEF provided 3 V of electrical potential during osseointegration. Histologic sections were stained with hematoxylin-eosin and observed under light microscopy. The sections were analyzed histomorphometrically to calculate the amount of newly formed bone. Statistical analysis was performed with SPSS 11.0 computer software (alpha= 0.05). RESULTS: At the end of the first stage of the osseointegration (90 days) CEF group sections showed enhanced growth of the trabeculae compared with the control group. Statistical analysis revealed significant differences between experimental and control groups. Bone contact ratio was statistically significant in the experimental group (p= 0.001). An increase in the local bone formation and bone contact ratio was observed with direct electrical stimulation of the implant and the bone area around the implant. CONCLUSION: Minimal direct electrical current, which can produce an electrical field around the implant, can increase the amount of bone formation and decrease the time of osseointegration.     

补骨合剂促进口腔种植体骨性结合的组织形态学研究

目的 :通过观察补骨合剂对口腔骨内种植体骨性结合的组织形态学指标的影响 ,探讨补骨合剂促进骨性结合的作用机理。方法 :成年杂种犬20只 ,拔除左侧下颌第二、三、四前磨牙 ,3个月后植入CDIC种植体3枚,随机分为实验组与对照组。实验组每日予补骨合剂1ml/kg灌胃 ,分别于术后1、2、4、8、12周取出标本行组织形态计量学分析 ,观察种植体 -骨界面骨性结合情况。结果:实验组第1周成骨细胞指数和骨矿化沉积速率显著高于对照组(P<0.01) ;第2、12周实验组骨融合指数比对照组显著提高(P<0.05) ;第2周实验组骨缺损面积显著减少(P<0.05)。结论 :补骨合剂可以促进口腔骨内种植体骨性结合,①可增加早期成骨细胞的数量与活性 ,促进骨基质的合成 ;②提高早期骨矿化沉积速率 ,促进钙磷酸盐的沉积     

富含血小板血浆诱导口腔种植体周围骨再生的实验研究

目的:通过犬下颌骨种植周围缺损模型,探讨与评估富含血小板血浆与磷酸三钙联合应用后,对种植体骨结合的效应。方法:采用自身对照,在6只成年杂种犬双侧下颌骨下缘各植入2颗纯钛种植体(共24颗)并在种植体周围造成缺损。右下颌2颗为对照组,在缺损处填入磷酸三钙和生理盐水的混合物,左下颌2颗为实验组,在缺损处填入磷酸三钙和富血小板血浆的混合物;术后4、8、12周分别处死2只犬,先后行大体观察、电镜观测和组织学观察。结果:大体观察实验组比对照组缺损处愈合更平整且种植体更稳定;4、8、12周电镜观测时均示实验组和对照组有显著性差异,实验组种植体骨结合率高;组织学观察在实验组可见大量成骨细胞、骨细胞及新生骨小梁,新生骨组织较成熟,而对照组成骨细胞少、骨小梁细而少、纤维组织多见。结论:富含血小板血浆可能具有促进新骨形成及种植体骨结合的效应。     

补骨合剂促进口腔种植体骨整合的免疫组织化学研究

目的：通过观察补骨合剂对口腔骨内种植体骨整合免疫组织化学指标的影响,探讨补骨合剂促进骨整合的作用机理。方法：成年杂种犬20只,拔除左侧下颌第二、三、四前磨牙,3个月后各植入CDIC种植体3枚,随机分为实验组和对照组,实验组每日予补骨合剂1ml/kg灌胃,分别于术后1、2、4、8、12周取出标本进行免疫组织化学分析,观察种植体一骨界面骨整合情况。结果：实验组第1周种植体－－骨形成蛋白（BMP）平均灰度显著增高（P＜0.01）,较对照组提前约1周。结论：补骨合剂可以促进口腔骨内种植体骨整合。该药物可促进BMP的早期释放和聚集,提高种植体－－骨界面的BMP浓度,促进其成骨。     

Implant osseointegration in the irradiated mandible. A comparative study in dogs with a microradiographic and histologic assessment

This research focuses on the effects of radiotherapy on the osseointegration of dental implants placed before or after radiotherapy in 11 male beagles. After the extraction of all mandibular premolars 1st and 2nd molars, three dogs were implanted without radiotherapy (Control group), four dogs were irradiated 4 weeks after implantation (IrA group) and four dogs were irradiated 8 weeks before implantation (IrB group). Eight implants were placed in each dog, in an alternating pattern: four nonsubmerged ITI Bonefit titanium plasma spray-coated and four submerged Steri-Oss hydroxyapatite-coated. The irradiated dogs received 4.3 Gy daily for 10 days. Two different fluorescent markers were administered at the time of implantation and of irradiation. The dogs were sacrificed 6 months after implantation, i.e. 5 months after radiotherapy for the IrA group and 8 months for the IrB group. Each mandible was submitted to histological and microradiographic analysis. Bone formation occurred around 85 of the 88 implants and consisted mostly of the successive deposit of woven and lamellar bone. Both irradiated groups showed obvious bone remodeling in alveolar bone as well as in the basilar part of the mandible. Nevertheless, in the IrA group, the resorption phenomena predominated over osteogenesis. The balance between these two opposite processes seemed to be restored 8 months after the end of radiotherapy (IrB group). In spite of focal lesions of radiation-specific bone destruction emphasized in some irradiated dogs, we conclude from our results that osseointegration of dental implants is possible in irradiated bone tissue.     

Implant Osseointegration in Circumferential Bone Defects Treated with Latex‐Derived Proteins or Autogenous Bone in Dog's Mandible

Background: In sites with diminished bone volume, the osseointegration of dental implants can be compromised. Innovative biomaterials have been developed to aid successful osseointegration outcomes. Purpose: The aim of this study was to evaluate the osteogenic potential of angiogenic latex proteins for improved bone formation and osseointegration of dental implants. Materials and Methods: Ten dogs were submitted to bilateral circumferential defects (5.0 × 6.3 mm) in the mandible. Dental implant (3.3 × 10.0 mm, TiUnite MK3?, Nobel Biocare AB, Göteborg, Sweden) was installed in the center of the defects. The gap was filled either with coagulum (Cg), autogenous bone graft (BG), or latex angiogenic proteins pool (LPP). Five animals were sacrificed after 4 weeks and 12 weeks, respectively. Implant stability was evaluated using resonance frequency analysis (Osstell Mentor?, Osstell AB, Göteborg, Sweden), and bone formation was analyzed by histological and histometric analysis. Results: LPP showed bone regeneration similar to BG and Cg at 4 weeks and 12 weeks, respectively (p ≥ .05). Bone formation, osseointegration, and implant stability improved significantly from 4 to 12 weeks (p ≤ .05). Conclusion: Based on methodological limitations of this study, Cg alone delivers higher bone formation in the defect as compared with BG at 12 weeks; compared with Cg and BG, the treatment with LPP exhibits no advantage in terms of osteogenic potential in this experimental model, although overall osseointegration was not affected by the treatments employed in this study.     

Effect of surface contamination on osseointegration of dental implants surrounded by circumferential bone defects

Objective: This study was designed to evaluate the effect of surface contamination on osseointegration of dental implants surrounded by a circumferential bone defect and to compare osseointegration around Osseotite® with that around Nanotite^? implants. Materials and methods: The premolars on both sides of the mandible in four beagle dogs were extracted. Following 4 months healing, two Nanotite^? implants and two Osseotite® implants were partially inserted in the left side of each mandible. Some threads protruded from the tissues into the oral cavity. Following a 5 week healing period, the implants were removed and the contaminated part of each implant was cleaned. They were then installed to the full implant length on the contra lateral side of the mandibles. The coronal 5 mm of each implant was surrounded by 1 mm circumferential bone defect. Following 12 weeks of healing period, the dogs were sacrificed and biopsies were obtained. Ground sections were prepared for histomorphometric analysis. Results: All implants were associated with direct bone‐to‐implant contact on the portion of the implant surface contaminated previously and surrounded by bone defect. Nanotite^? implants performed better than Osseotite® implants. Conclusions: The results demonstrated that implant surfaces, which were contaminated previously and were surrounded by bone defects, can osseointegrate. To cite this article:
Mohamed S, Polyzois I, Renvert S, Claffey N. Effect of surface contamination on osseointegration of dental implants surrounded by circumferential bone defects. Clin. Oral Impl. Res. 21 , 2010; 513–519.
doi: 10.1111/j.1600‐0501.2010.01913.x     

钛网成形自体颗粒骨修复下颌骨缺损并同期种植的实验研究

目的 观察犬钛网成形自体颗粒骨移植修复下颌骨节段性缺损并同期植入钛种植体后的骨愈合和骨结合情况.方法 5只Beagle犬,一侧下颌骨制备长40 mm的节段性缺损;钛网成形修复下颌骨缺损.将切除后的下颌骨和自体髂骨剪成直径约2mm颗粒,骨皮质、骨松质体积比3∶1混合,紧密充填在钛网内,将2枚纯钛种植体埋置于颗粒骨内,术后6个月处死动物.用下颌骨X线片、组织学切片、扫描电镜以及能谱分析观察钛网内颗粒骨愈合以及种植体骨结合的情况.结果 钛网成形自体颗粒骨移植重建后的下颌骨外形满意,功能正常、颗粒骨成骨良好、结构优良,未见明显骨吸收.同期植入的种植体能够与周围骨组织形成良好的骨结合,并有促进邻近骨组织结构优化的趋势.结论 钛网成形自体颗粒骨移植是一种修复下颌骨节段性缺损的好方法,当修复后下颌骨形态良好、骨质优良、骨量充足时可以同期植入种植体.     

Resolution of surgically created three‐wall intrabony defects in implants using three different biomaterials: an in vivo study

Objectives: To histomorphometrically analyze bone formation on amorphous calcium phosphate (ACP), micro‐macroporous biphasic calcium phosphate (MBCP), and freeze‐dried bone allograft (FDBA) in three‐wall defects adjacent to structured surface with calcium phosphate nanocoating implants in dogs. Materials and methods: Five male mixed‐breed dogs were used in this study. The premolars and molars were extracted on both sides of the mandible. Eight weeks after extraction, four implants were submerged on each side of the mandible. Three‐wall intrabony defects (5 × 3 × 3 mm) were surgically created adjacent to the implants before installation. No grafts were placed in the control group. At the experimental sites, each intrabony defect was grafted with either ACP, MBCP, or FDBA. The dogs were sacrificed after 12 weeks, and histological and histomorphometrical analyses of the implant sites were performed. Results: All of the three experimental groups exhibited defect resolution and osseointegration that showed a statistically significant difference compared with the control group in terms of remaining defect depth and bone‐to‐implant contact (BIC). However, there were no statistical significances among the three experimental groups. MBCP had the highest BIC (63.57 ± 21.57%), followed by ACP and FDBA. The control group showed the least bone area and the greatest remaining defect depth. Conclusion: Grafts with the synthetic biomaterials ACP and MBCP showed bone regeneration that was similar to FDBA in surgically created three‐wall intrabony defects adjacent to implants. Within the limitations of this study, it can be concluded that ACP and MBCP synthetic biomaterials are as effective as FDBA at osteoconduction. To cite this article:
Choi J‐Y, Jung U‐W, Lee I‐S, Kim C‐S, Lee Y‐K, Choi S‐H. Resolution of surgically created three‐wall intrabony defects in implants using three different biomaterials: an in vivo study.
Clin. Oral Impl. Res 22 , 2011; 343–348.
doi: 10.1111/j.1600‐0501.2010.01978.x