在即刻种植术中应用两种不同方法处理骨缺损效果的比较

目的:比较珊瑚羟基磷灰石(CHA)复合富血小板血浆(PRP)或覆盖生物膜在即刻种植术中对骨再生效果的影响。方法:8只成年实验用犬,拔除双侧第2、3、4下颌前磨牙,同期植入种植体,制备种植体颈部的环状骨缺损,每侧植入3颗种植体,将种植体随机分为3组:A组,植入珊瑚羟基磷灰石和富血小板血浆的混合物;B组植入珊瑚羟基磷灰石,并覆盖可吸收胶原膜;C组作为对照组,不植入任何材料。术后3个月处死动物,先后进行大体观察、组织形态学观察、及生物力学测定,比较组间差异。结果:A组新生骨质较优,骨量多,B组骨缺损区无软组织长入,两者间骨结合率差异无统计学意义(P>0.05)。C组骨再生效果较差,与A、B两组相比,差异有统计学意义(P<0.05)。3组标本生物力学测试结果差异均有统计学意义。结论:两种处理方法对种植体周的骨再生均有积极作用,富血小板血浆在促进骨组织生长方面优势明显,生物膜在阻挡软组织长入方面效果较优。     

富血小板血浆复合珊瑚羟基磷灰石在即刻种植术中的应用

目的:探讨富血小板血浆复合珊瑚羟基磷灰石,修复即刻种植时种植体周围骨缺损的效果。方法:8只实验用犬,拔除双侧下颌第2、3、4前磨牙,每个拔牙窝即刻植入1枚种植体,并制备种植体颈部的半环状骨缺损。将同一实验犬的6处种植体周骨缺损随机分为3组给予不同方法处理,每组2处。具体如下:A组骨缺损中植入珊瑚羟基磷灰石-富血小板血浆复合物,B组骨缺损中单纯植入珊瑚羟基磷灰石,C组中骨缺损空置。术后3个月处死动物,制作标本,分别进行大体观察,生物力学测试,组织形态学观察、测试(骨结合率)。结果:骨结合率、生物力学结果一致,均为A组最佳,B组次之,C组最差,且3组间差异有统计学意义(P<0.05)。结论:富血小板血浆复合珊瑚羟基磷灰石可促进即刻种植时种植体周围的骨生成,提高骨结合率。     

Bio-oss结合Bio-gide修复牙种植体周围骨缺损的组织学研究

目的：通过制作带有种植体的硬组织磨片,评价无机牛骨(deproteinized natural bovine mineral,Bio-oss)结合可吸收性胶原膜(bioresorbable collagen mambrane,Bio-gide)在牙种植体周围骨缺损中的引导骨再生作用及效果。方法：在免股骨植入羟基磷灰石涂层BLB种植体,并在其外侧壁制造标准骨缺损,A组在骨缺损处植入Bio-oss颗粒并在其表面覆盖Bio-gidt,膜,B组作为空白对照,分别于术后1、2、4、6个月取样品,通过带种植体的硬组织切片进行骨组织形态学分析。结果：术后1个月Bio-oss颗粒表面有新骨形成,随时间延长Bio-oss发生降解吸收,新生骨量增加,并与种植体表面形成骨性结合。结论：可吸收性胶原膜Bio-gide结合Bio-oss应用于牙种植体周围骨缺损中,可以引导骨组织再生,重建缺损的骨组织,新生骨与种植体形成骨性结合。     

rhBMP-2在种植体周围骨缺损修复中应用的组织学观察

目的:研究rhBMP-2及不同载体在种植体周围骨缺损修复中的应用。方法:在beagle犬下颌骨植入种植体,颊侧形成裂开性骨缺损,置入复合了不同浓度rhBMP-2的珊瑚羟基磷灰石人造骨(CHA)或可吸收胶原海绵(ACS)。种植体植入后2、4、8、12周,获取含种植体骨标本,进行组织学观察。结果:2周时,rhBMP-2组可见极少量的新生骨组织。4周时,rhBMP-2/ACS组新骨组织由牙槽骨顶端向缺损区中心方向生长;rhBMP-2/CHA组人造骨颗粒内部和周围出现呈岛状生长的新生骨组织。8周时,rhBMP-2/ACS组的新骨形成大片状结构;rhBMP-2/CHA组人造骨颗粒周围较多骨岛形成。12周时,rhBMP-2组的缺损区内骨量和骨高度进一步增加,与种植体形成骨性结合。浓度为0.05 mg/ml和0.2 mg/ml,载体为CHA或ACS促进骨再生作用差异无统计学意义。结论:以CHA或ACS为载体rhBMP-2能促进种植体周围骨缺损区内的骨组织再生并与种植体表面较好地结合。     

可吸收性胶原膜引导即刻植入种植体周围骨组织再生的实验研究

目的探讨可吸收性胶原膜引导即刻植入种植体周围骨组织再生的效果。方法在12只成年杂种狗下颌第3、4前磨牙新鲜拔牙创即刻植入种植体的近中形成3 mm×3 mm×5 mm骨缺损区,按自身同期对照研究设计,右侧为实验侧,骨缺损区上覆盖Co膜;左侧为空白对照侧,骨缺损区不覆盖Co膜。术后1、2、4、6个月分别处死一组动物,摘取下颌骨,采用大体观察、X线摄片、组织学观察、扫描电镜及生物力学（拔出实验）测定等方法检测缺损区骨组织再生的情况。结果实验侧种植体周围骨缺损区较空白对照侧新骨形成量多、外形好、骨成熟时间早,加速了骨组织的再生过程。结论可吸收性胶原膜具有良好的生物相容性和可降解性,可用作骨组织引导再生膜,以期促进骨缺损的再生修复,其促进作用主要表现在骨组织愈合的早期。     

可吸收胶原膜在即刻种植中应用的超微结构及生物力学研究

目的:评估引导骨组织再生技术在即刻种植中促进种植体周围骨缺损修复的效果及作用,为可吸收性胶原膜的临床应用提供理论依据。方法:16只成年杂种犬,双侧下颌第三、四磨牙拔除后行即刻种植,右侧使用可吸收膜覆盖骨缺损区,左侧不覆盖任何膜作空白对照。分别于术后1、2、4、6个月时各处死4只犬,取材观察。采用扫描电镜(SEM)、四环素荧光标记及生物力学测定等方法,检测即刻植入种植体周围缺损区骨组织再生修复的情况。结果:SEM和四环素荧光标记显示,实验组种植体周围骨缺损的再生修复较同期空白对照组快,术后6个月实验组缺损区呈完全骨性修复,成骨活动趋于稳定,而对照组近牙槽嵴顶仍可见尚不成熟的新生骨组织。生物力学测试结果表明,术后1、2、4个月实验组与对照间最大拔出力值间差异有显著性(P<0.05),术后6个月差异无显著性(P>0.05)。结论:可吸收胶原膜用作骨组织引导再生膜,可以促进骨缺损的早期修复。     

胶原-羟基磷灰石人工骨与胶原膜引导牙周组织再生的动物实验研究

目的：将胶原-羟基磷灰石人工骨与胶原膜联合应用于修复牙周缺损的动物实验,探讨其用于引导牙周组织再生的可行性。方法：人工构建4只成年Beagle犬下颌后牙区牙周缺损模型,分别随机采用：胶原-羟基磷灰石人工骨/胶原膜、胶原-羟基磷灰石人工骨、空白对照治疗,每组8颗牙,12周后处死动物,进行组织学观察并测量新生组织高度。结果：与单纯植入胶原-羟基磷灰石人工骨组相比,胶原-羟基磷灰石人工骨/胶原膜组获得了更多的新附着,表现为有较多的新生牙槽骨、新生牙周膜和新生牙骨质样组织生长,2组之间新生组织差异有显著性（P〈0.05）。结论：胶原-羟基磷灰石人工骨与胶原膜联合运用修复牙周牙槽骨缺损引导牙周组织再生的效果优于单纯植入人工骨。     

异种脱细胞真皮基质联合珊瑚羟基磷灰石在GBR术中的应用

目的：评价异种脱细胞真皮基质联合珊瑚羟基磷灰石在引导骨组织再生术中的应用效果。方法：17例共27颗牙缺失患者作为研究对象,其中10颗上前牙牙槽骨宽度约4mm的延期种植先行骨挤压术植入种植体再行GBR术,其余12颗延期即刻种植上前牙及5颗环状骨缺损后牙常规植入种植体后行GBR术。6-8m后观察成骨效果。结果：除一例患者右上侧切牙植体颈部唇侧暴露约1.5mm左右,其余患者植体均被新生骨包绕,成骨效果显著。结论：异种脱细胞真皮基质联合珊瑚羟基磷灰石在牙种植术中引导骨组织再生效果良好。     

骨诱导术在牙种植骨量不足病例的临床应用

目的:探讨应用诱导骨组织再生技术在种植牙时颌骨骨量不足的临床应用研究。方法:选择35例在种植手术时,种植体周围骨量不足的患者,采用可吸收胶原膜(Bio-Gide)和骨粉(Bio-Oss)行诱导骨组织再生,观察其促进颌骨再生和种植体骨整合的临床效果。结果:经6～18个月的临床观察和放射X线片检查,种植体周围骨缺损区骨组织再生情况良好,种植体稳定。结论:采用可吸收胶原膜(Bio-Gide)和骨粉(Bio-Oss)诱导再生技术用于种植牙术骨量不足的患者,可成功诱导骨组织再生、重建缺损的骨组织,促进种植体与新生骨组织形成良好的骨性结合。     

无机牛骨结合可吸收性胶原膜修复种植牙骨缺损的定量分析

目的 :评价无机牛骨 (deproteinizedbovinebonemineral,Bio -oss)与可吸收性胶原膜 (bioresorbablecollagenmembrane ,Bio -gide)在种植牙骨缺损中的引导骨再生作用。方法 :在 30只兔子股骨植入羟基磷灰石涂层BLB种植体 (3.3mm× 8mm) ,然后在其侧壁制造标准骨缺损 (4mm× 3mm× 3mm) ,骨缺损内植入Bio -oss,并在其表面覆盖Bio-gide膜 ,分别于术后 1、4、6个月取样本 ,制备带种植体的硬组织切片 ,通过计算机组织图像分析系统定性与定量分析。结果 :术后 1个月Bio -oss颗粒表面有新骨形成 ,随时间延长 ,新生骨量增加 ,Bio -oss百分率下降 ,6个月时新生骨百分率达 37% ,而Bio -oss百分率由 35 %下降到 2 5 % (P <0 .0 5 )。结论 :Bio -Oss结合可吸收性胶原膜使牙种植中的骨缺损获得重建 ,Bio-Oss是一种骨引导材料 ,引导骨组织再生并逐渐被新生骨所取代     

Comparison of bioabsorbable and bioinert membranes for guided bone regeneration around non‐submerged implants. An experimental study in the mongrel dog.

The aim of this clinical investigation was to evaluate the effect of guided bone regeneration around non-submerged implants using different barrier membranes. Five adult mongrel dogs were used in this investigation. After having all premolars extracted and implant osteotomies performed in the regions of the former premolars, buccal bone defects were created. Subsequently, 3 implants were placed and the defects treated with 1 of the following 3 modalities: a) guided bone regeneration using an expanded polytetrafluoroethylene membrane, b) guided bone regeneration using a bioabsorbable membrane made from a synthetic copolymer of glycolide and lactide and c) no membrane application. Following implant and membrane placement, the mucoperiosteal flaps were repositioned and tightly sutured around the neck of the implants allowing for a non-submerged healing. After a healing period of 6 months, the animals were sacrificed and the specimens processed for histologic evaluation. The clinical pre-treatment defects between the different treatment groups were not statistically different (bioinert membrane group: 4.9 mm; control group: 4.8 mm; bioabsorbable membrane group: 4.5 mm). The remaining histological defects after 6 months of healing amounted to approximately 2.5 mm in the bioinert membrane group, 5.7 mm in the control group and 6.0 mm in the bioabsorbable membrane group. A significant difference was observed between the bioinert membrane group and the other 2 groups. The mineralized bone-to-implant contact in the bioinert membrane group was 51.5%, in the control group 46.3% and in the bioabsorbable membrane group 37.5%. The values between the bioinert membrane group and the bioabsorbable membrane group were statistically different. The results of this study indicate that bone regeneration with bioinert e-PTFE membranes around non-submerged implants is possible. The utilized absorbable polyglycolic/polylactid membrane did not show any bone regenerative effect and the results did not differ from the control group without membrane application.     

Rotated split palatal flap for soft tissue primary coverage over extraction sites with immediate implant placement. Description of the surgical procedure and clinical results.

Immediate implant placement after tooth extraction is becoming a common procedure in implant-supported oral rehabilitation. However, lack of primary full flap closure can jeopardize final results. A surgical approach that would enable predictable primary soft tissue closure over implants placed into fresh extraction sockets is described and evaluated. This technique is based on a rotated deep split thickness palatal flap (RSPF) containing periosteum and connective tissue, covering the implant and/or a barrier membrane. In 29 patients, 33 consecutive implants were placed immediately post extraction of 1 or 2 anterior or premolar maxillary teeth. Patients were divided in 2 groups: Group A (15 patients; n = 18 sites) where no barrier membrane was used and Group B (14 patients, n = 15 sites) where an occlusive resorbable collagen membrane was used. Distance between the alveolar crestal bone and the coronal aspect of the implant was measured at time of implant placement (Group A: mean 1.9 mm, SD 1.16; Group B: mean 4.6 mm, SD 1.18) and at second stage surgery (Group A: mean 0.3 mm, SD 0.46; Group B: mean 0. 7 mm, SD 0. 7). The difference between both records (crestal bone formation) was calculated (Group A: 1.7 mm, SD 1.03; Group B: 3.9 mm, SD 1.12) and found to be statistically significant (P <0.0001). Crestal bone formation, relative to the initial bone crest-implant distance at time of implant placement was approximately 85% in both groups. In 4 sites (2 in each group), where the cover screws were exposed before second stage surgery, complete crestal bone regeneration did not occur. Use of a barrier membrane may be obviated in appropriate cases while placing implants into fresh extraction sites. This procedure offers a predictable treatment approach in achieving complete soft tissue coverage, while allowing for healing of bony defects in immediate implantation procedures.     

A comparison between enamel matrix derivative and a bioabsorbable membrane to enhance healing around transmucosal immediate post-extraction implants

BACKGROUND: This clinical report compares the use of an enamel matrix derivative (EMD) and bioabsorbable barrier membrane to enhance healing following the immediate placement of transmucosal implants into extraction sockets. METHODS: Thirty-two adult patients scheduled for tooth replacement with dental implants agreed to participate. Following the insertion of a transmucosal implant into the extraction site, the subjects were assigned to one of two treatment alternatives of the remaining bone defects around the implants: 1) the residual bone defects were filled with EMD (EMD group) or 2) the residual bone defects were covered with a bioabsorbable membrane (membrane group). Flaps were then coronally positioned around implant cover screws. Patients followed weekly maintenance recalls for the first 6 weeks and then monthly recalls until the final prosthetic restoration was completed (after 6 months). The treatment outcome was evaluated after 12 months by the use of clinical variables. The null hypothesis of no treatment group differences was tested by the use of analysis of variance (ANOVA). RESULTS: At a 12-month follow-up, all of the implants were completely osseointegrated and successfully functioning, showing a success rate of 100%. The membrane group showed a significantly lower mean probing attachment level than the EMD group at proximal (0.60 mm, standard deviation (SD) 0.37 versus 1.19 mm, SD 1.10), buccal (0.80 mm, SD 0.79 versus 1.77 mm, SD 1.16), and lingual sites (0.44 mm, SD 0.52 versus 1.48 mm, SD 1.46). The difference was statistically significant at all sites (P < 0.05). With respect to the position of the soft tissue margin around the implant shoulder, the membrane group showed a consistently higher value than the EMD group at, respectively, proximal (1.30 mm, SD 2.37 versus 1.16 mm, SD 1.0), buccal (0.90 mm, SD 1.29 versus 0.22 mm, SD 1.47), and lingual sites (1.12 mm, SD 1.10 versus 0.55 mm, SD 1.42). CONCLUSIONS: The membrane group obtained more favorable results in terms of both the probing attachment level and peri-implant position of soft tissues compared to the EMD group. The use of a bioabsorbable membrane around immediately placed transmucosal implants enhanced soft and hard tissue healing and might be an advisable treatment choice particularly in areas with high esthetic demands.     

Qualitative analysis of peripheral peri-implant bone and influence of alendronate sodium on early bone regeneration.

BACKGROUND: Alendronate sodium increases alveolar bone density with systemic use. It inhibits osteoclast activity and is thought to result in a net increase in osteoblastic activity. However, little is known about local in vivo use. The purpose of this study was to evaluate the effect of local delivery of alendronate on bone regeneration within peri-implant defects. Peri-implant bone was examined histomorphometrically to evaluate the amount of supporting bone peripheral to the bone-implant interface. METHODS: Six adult hound dogs were evenly divided into 2 groups, with one group receiving alendronate-coated dental implants and the other group serving as controls. Dental implants were placed immediately after extraction of right and left second, third, and fourth mandibular premolars. Forty-eight dental implants were placed (2 types in each dog: 24 hydroxyapatite [HA]-coated and 24 titanium machine-polished [TMP]), for a total of 4 variables. A bioabsorbable collagen membrane was secured over the implants and defects, and the flaps closed primarily. The dogs were sacrificed on day 28. Specimens were sectioned, mounted, and stained with Stevenel's blue and van Gieson's picric fuchsin. The amount of bone adjacent and 1 mm peripheral to the implant surface was recorded with a computerized microscopic digitizer. RESULTS: Locally applied alendronate resulted in significantly increased amounts of bone (P<0.0002, ANOVA) in the peripheral area with both HA and TMP implants. However, the most influential factor in the amount of peripheral bone was the type of implant surface (P<0.0001). CONCLUSIONS: Local application of alendronate is useful in increasing the amount of peripheral peri-implant bone. Also, the amount of supporting bone was not related to the bone-to-implant contact but to the surface characteristics of the implant. The findings of the present study indicate that the evaluation of dental implant-supporting bone should include peripheral bone as well as bone-to-implant interface.     

A feasibility study evaluating an in situ formed synthetic biodegradable membrane for guided bone regeneration in dogs

Purpose: The aim was (1) to evaluate the soft‐tissue reaction of a synthetic polyethylene glycol (PEG) hydrogel used as a barrier membrane for guided bone regeneration (GBR) compared with a collagen membrane and (2) to test whether or not the application of this in situ formed membrane will result in a similar amount of bone regeneration as the use of a collagen membrane. Material and methods: Tooth extraction and preparation of osseous defects were performed in the mandibles of 11 beagle dogs. After 3 months, 44 cylindrical implants were placed within healed dehiscence‐type bone defects resulting in approximately 6 mm exposed implant surface. The following four treatment modalities were randomly allocated: PEG+autogenous bone chips, PEG+hydroxyapatite (HA)/tricalcium phosphate (TCP) granules, bioresorbable collagen membrane+autogenous bone chips and autogenous bone chips without a membrane. After 2 and 6 months, six and five dogs were sacrificed, respectively. A semi‐quantitative evaluation of the local tolerance and a histomorphometric analysis were performed. For statistical analysis, repeated measures analysis of variance (ANOVA) and subsequent pairwise Student's t‐test were applied (P<0.05). Results: No local adverse effects in association with the PEG compared with the collagen membrane was observed clinically and histologically at any time‐point. Healing was uneventful and all implants were histologically integrated. Four out of 22 PEG membrane sites revealed a soft‐tissue dehiscence after 1–2 weeks that subsequently healed uneventful. Histomorphometric measurement of the vertical bone gain showed after 2 months values between 31% and 45% and after 6 months between 31% and 38%. Bone‐to‐implant contact (BIC) within the former defect area was similarly high in all groups ranging from 71% to 82% after 2 months and 49% to 91% after 6 months. However, with regard to all evaluated parameters, the PEG and the collagen membranes did not show any statistically significant difference compared with sites treated with autogenous bone without a membrane. Conclusion: The in situ forming synthetic membrane made of PEG was safely used in the present study, revealing no biologically significant abnormal soft‐tissue reaction and demonstrated similar amounts of newly formed bone for defects treated with the PEG membrane compared with defects treated with a standard collagen membrane.     

Deproteinized bovine bone mineral in marginal defects at implants installed immediately into extraction sockets: an experimental study in dogs

Aim: To evaluate the influence of deproteinized bovine bone mineral (DBBM) particles concomitant with the placement of a collagen membrane on alveolar ridge preservation and on osseointegration of implants placed into alveolar sockets immediately after tooth extraction. Material and methods: The pulp tissue of the mesial roots of ₃P₃ was removed in six Labrador dogs and the root canals were filled. Flaps were elevated in the right side of the mandible, and the buccal and lingual alveolar bony plates were exposed. The third premolar was hemi‐sectioned and the distal root was removed. A recipient site was prepared and an implant was placed lingually. After implant installation, defects of about 0.6 mm wide and 3.1 mm depth resulted at the buccal aspects of the implant, both at the test and at the control sites. The same surgical procedures and measurements were performed on the left side of the mandible. However, DBBM particles with a size of 0.25–1 mm were placed into the remaining defect concomitant with the placement of a collagen membrane. Results: All implants were integrated into mature bone. No residual DBBM particles were detected at the test sites after 4 months of healing. Both the test and the control sites showed buccal alveolar bone resorption, 1.8±1.1 and 2.1±1 mm, respectively. The most coronal bone‐to‐implant contact at the buccal aspect was 2±1.1 an 2.8±1.3 mm, at the test and the control sites, respectively. This difference in the distance was statistically significant. Conclusion: The application of DBBM concomitant with a collagen membrane to fill the marginal defects around implants placed into the alveolus immediately after tooth extraction contributed to improved bone regeneration in the defects. However, with regard to buccal bony crest preservation, a limited contribution of DBBM particles was achieved. To cite this article:
Caneva M, Botticelli D, Pantani F, Baffone GM, Rangel IG Jr, Lang NP. Deproteinized bovine bone mineral in marginal defects at implants installed immediately into extraction sockets: an experimental study in dogs.
Clin. Oral Impl. Res. 23 , 2012; 106–112.
doi: 10.1111/j.1600‐0501.2011.02202.x     

膜诱导组织再生技术用于牙种植的实验研究：Ⅰ扩大牙种植适应证

目的：为临床应用膜放组织再生技术扩大牙种植适应证提供理论依据。方法：在拔除前磨牙的同时，造成颊侧骨板缺损，即刻种植羟基磷灰石涂层钛种植体或纯钛种植体，并运用胶原膜覆盖颊侧种植体暴露面和骨面，观察种植体周骨组织再生情况，结果：经过一年的放射学和组织学观察，表明种植周骨组织有不同程度的再生，大多数种植体稳固，结论：膜诱导组织再生技术可作用于牙种植的临床治疗。     

Guided bone regeneration for immediate non‐submerged implant placement using bioabsorbable materials in Beagle dogs

The aim of the present study was to evaluate the combined application of different bioabsorbable materials for healing of residual peri‐implant defects after placement of non‐submerged implants into fresh extraction sockets. Second and third mandibular premolars were extracted from 10 Beagle dogs, the coronal part of the distal sockets were surgically enlarged and this was followed by immediate placement of specially designed hollow‐screw non‐submerged dental implants. For each animal, the coronal peri‐implant defects were further treated with one of the 4 following procedures: 1) no treatment, control site: 2) grafting with porous hydroxyapatite (HA); 3) collagen membrane tightly secured around the implant and over the defect and 4) grafting with HA covered with a collagen membrane. After 16 weeks of healing, specimens were removed from the mandibule and prepared for a histomorphometric evaluation. The bone-to-implant contact length (BIC) was measured and compared amongst the different treatment modalities. In the defect area, the irregular bone regeneration was similar between all the treatment procedures ( P >0.10). In the sites covered with a collagen membrane alone, the total BIC (47%) was greater than in control sites (28.7%. P <0.05) or sites grafted with HA (22.2%, P <0.02). Total BIC in sites treated with the HA‐membrane combination (43%) was only significantly different from sites treated with HA ( P <0.10). It is concluded that the use of bioabsorbable materials results in a limited increase of osseointegration when used in conjunction with immediate placement of non-submerged implants, although the principle of the one stage surgical approach can be maintained.