种植前牙槽骨保存的动物实验

目的探讨外科级半水硫酸钙（SGCS）和富血小板血浆（PRP）复合物在种植前牙槽骨保存中应用的可行性。方法利用SGCS和PRP复合物、SGCS植入5只犬两侧手术区后，采用螺旋CT、放射性核素骨显像、X线片、组织学和组织形态计量技术，比较牙槽骨修复后的变化。结果SGCS和PRP复合物减小了牙槽骨吸收，提高了新骨生成的代谢活性和种植体的骨结合率。而在SGCS中加入PRP仅在早期表现出较高的骨代谢活性。结论在本项实验中，SGCS和PRP复合物可用于种植前牙槽骨的保存。     

Early healing of implants placed into fresh extraction sockets: an experimental study in the beagle dog. II: ridge alterations

Aims: To describe the early phases of healing at the alveolar ridge around dental implants placed into fresh extraction sockets and to study whether (i) the dimension of the socket and (ii) a new implant surface nano-topography may have any influence.
Materials and Methods: Sixteen beagle dogs received 64 test (new surface) and control implants randomly placed at the distal socket of 3P3 and 4P4. The implant shoulder was levelled with the marginal buccal bone crest. Animals were sacrificed at 4 h, 1, 2, 4 and 8 weeks for histological examination.
Results: Bone loss occurred at the buccal crest between the 4-h and 1-week healing intervals, being more pronounced at the third premolar site [vertical bone loss between day 0 and 8 weeks 1.1 (0.5) mm]. The corresponding loss at the fourth premolar site was 0.3 (0.5) mm. Test sites containing implants with discrete crystalline deposition nano-particles' surface exhibited less buccal bone resorption than control sites at 8 weeks.
Conclusion: Dimensions of the socket influenced the process of wound healing of implants placed into fresh extraction sockets, with more bone loss in the narrower sockets; however, the implant surface nano-topography seemed to have a limited effect in the healing of this implant surgical protocol.     

Immediate implants at fresh extraction sockets: bone healing in four different implant systems

Objectives: To describe the differences in bone healing, when placing four different implant systems in fresh extraction sockets.
Material and Methods: Eight beagle dogs received implants randomly installed into the distal socket of three P3 and four P4. Four-implant systems were evaluated. Each animal provided four test implant sites. All animals were sacrificed at 6 weeks after implant placement, providing specimens for histo-morphometric analysis of bone to implant contact (BIC), bone area, new bone formation, as well as histometric measurements of the ridge alterations.
Results: No statistically significant difference was observed among the four-implant systems. The mean BIC % ranged between 58.5% and 72.1%. Bone modelling of the buccal plate was marked and amounted approximately to 2.5 mm, independently of the system used.
Conclusion: This study failed to demonstrate differences in the healing pattern after 6 weeks when placing four different implant systems in fresh extraction sockets. In spite of achieving predictable osteointegration with the four implants studied, the occurrence of buccal bone resorption may limit the use of this surgical approach.     

拔牙窝内植入不同深度骨水平种植体周围软硬组织改建的组织形态变化

目的 比较新鲜拔牙窝内植入不同深度种植体后软、硬组织的变化。方法 6只成年拉布拉多犬的双侧前磨牙拔除后,立即将24颗种植体以不同深度植入拔牙窝内。将Straumann^®骨水平种植体按以下不同深度植入拔牙窝—颊侧牙槽嵴下2 mm,颊侧牙槽嵴下1 mm,与牙槽嵴齐平,以及颊侧牙槽嵴上方1 mm。愈合6个月后采集样本,获得未脱钙切片,进行组织学观察、测量,获得垂直骨吸收和生物学宽度。采用SPSS 19.0软件包对数据进行统计学分析。结果 所有种植体均获得成功骨结合。骨吸收以种植体植入牙槽嵴下2 mm处最显著（P<0.05）。以不同深度植入时,生物学宽度无显著差别。结论 在新鲜拔牙窝内植入种植体时,不同植入深度对骨吸收有影响。当植入深度为骨下2 mm时,骨吸收最多。     

富血小板血浆对骨移植后颌骨缺损愈合早期骨代谢活性的影响

目的：探讨富血小板血浆对颌骨缺损愈合早期骨代谢活性的影响.方法：拔除5只狗双侧下颌第一磨牙后扩大牙槽窝，形成骨缺损模型。实验侧植入Osteoset和富血小板血浆，对照侧植入Osteoset。术后2、4、6周对缺损区进行^99m锝骨显像定量测定缺损区新骨生成代谢活性。结果：各缺损区均呈现放射性核素浓集区，并在第4周达到高峰。实验组与对照组仅在第2周放射性计数有显著性差异，而在第4、6周没有显著性差异。结论：富血小板血浆可促进骨移植后颌骨缺损愈合骨代谢活性，其效应在术后早期表现出来。     

Influence of the interimplant distance on crestal bone resorption and bone density: a histomorphometric study in dogs

BACKGROUND: The position of gingival soft tissues depends on the position and health of the underlying alveolar bone. The aim of this study was to evaluate the influence of different interimplant distances on crestal bone resorption after prosthetic restoration with a 5-mm distance between the contact point and the bone crest. METHODS: The mandibular bilateral premolars of six dogs were extracted and, after 12 weeks, each dog received eight implants, totaling 48 implants in the experiment. Two pairs, one in each hemiarch, were separated by 2 mm (group 1) and two by 3 mm (group 2). After 12 weeks, the implants received temporary acrylic prostheses. After 4 more weeks, metallic crowns substituted the temporary prostheses. After 4 more weeks, the animals were sacrificed, and their hemimandibles were removed, dissected, and processed. RESULTS: For groups 1 and 2, respectively, the mean of interimplant bone resorption (IIBR) analyzed histologically was 2.03 and 1.98 mm (P >or=0.05), and the mean of the distal extension bone resorption was 2.04 and 1.92 mm for groups 1 and 2, respectively (P >or=0.05). The crestal bone resorption between the implants was 0.13 mm (P >or=0.05) for both groups. The mean of IIBD for groups 1 and 2 was 79% and 80%, respectively. When the IIBD was compared to the distal extension bone density for group 1 (79% and 64%) and group 2 (80% and 62%), statistically significant differences were obtained for both groups (P 相似文献   

Facilitation of beta-tricalcium phosphate-induced alveolar bone regeneration by platelet-rich plasma in beagle dogs: a histologic and histomorphometric study

PURPOSE: The effects of 2 graft materials, beta-tricalcium phosphate (Cerasorb) alone and a combination of Cerasorb and platelet-rich plasma (PRP), on the bone regeneration process were evaluated in the canine mandible. MATERIALS AND METHODS: The mandibular premolars of 12 beagle dogs were surgically removed. The extraction sockets were filled with Cerasorb on the control side and a mixture of Cerasorb and PRP on the test side. Bilateral biopsy samples were taken from the graft insertion sites at 6, 12, and 24 weeks after surgery. Sections were prepared from the undecalcified resin-embedded samples. RESULTS: Six weeks after grafting, the proliferation of cellular osteogenic mesenchyma was more abundant in the test group. The histomorphometric data revealed a significantly higher percentage of bone area in the test group (45.9%) than in the control group (30.8%) (P < .05). Twelve weeks after grafting, the test group still had some advantage over the control group in terms of bone regeneration (52.5% bone in the test group versus 49.4% in the control group, P < .05). Twenty-four weeks after grafting, bone-forming activity was nearly equal in the 2 groups, and the bone area in the 2 groups did not differ significantly (62.9% and 61.9%, respectively) (P < .05). DISCUSSION: The histomorphometric results suggested more intensive bone regeneration in the early healing phase following the topical application of PRP. CONCLUSION: The increase in bone density facilitated by grafting with a combination of Cerasorb and PRP requires thorough study in humans.     

A new injectable calcium phosphate biomaterial for immediate bone filling of extraction sockets: a preliminary study in dogs.

BACKGROUND: Many different bone substitutes, such as autografts, allografts or synthetic biomaterials have been proposed to restore alveolar bone loss and support efficient placement of dental implants. This experimental study evaluated the osteoconductive properties of an injectable bone substitute (IBS) composed of a polymeric carrier and a calcium phosphate mineral phase, used to fill mandibular and maxillary canine extraction sockets. METHODS: The polymer was a cellulose derivative (methyl-hydroxy-propyl-cellulose, MHPC), and the mineral phase consisted of granules of biphasic calcium phosphate (BCP) ceramics 200 to 500 microm in diameter. Mandibular and maxillary premolars extracted from 3 dogs (a total of 60 extraction sites) were immediately treated with the IBS or left unfilled as control sites. Animals were sacrificed 3 months after implantation and all extraction sockets were prepared for histological evaluation. RESULTS: Qualitative histological studies showed that the IBS was able to support the extensive apposition of well-mineralized newly formed lamellar bone over the entire socket surface and appeared to prevent alveolar ridge bone loss in treated extraction sites. Quantitative evaluation showed that the amount of newly formed bone was significantly higher in mandibular than maxillary extraction sockets for both treated and control sites. CONCLUSIONS: An injectable bone substitute composed of a polymeric carrier and calcium phosphate was effective in enhancing the bone fill of extraction sockets. This approach may prove promising for periodontal lesions. The material expressed osteoconductive capacities, and the biological properties of the mineral phase were conserved.     

Histological comparison of healing extraction sockets implanted with bioactive glass or demineralized freeze-dried bone allograft: a pilot study

BACKGROUND: Various materials have been used immediately following tooth extraction to fill and/or cover the socket in an attempt to limit or prevent ridge resorption. The purpose of the present pilot study was to establish a reliable model to investigate the effect of various bone graft and bone replacement materials on extraction socket healing. This study also compared healing extraction sockets 6 to 8 months postimplantation of a bioactive glass (BG) or demineralized freeze-dried bone allograft (DFDBA) to an unfilled socket control (C). METHODS: Following tooth extraction, a total of 30 sockets in 19 patients were randomly divided into 3 treatment groups: 10 sockets received BG, 10 sockets DFDBA, and 10 sockets served as unfilled controls. Primary coverage was achieved by flap advancement over each socket. Six to 8 months postextraction at time of implant placement, histological cores of the treatment sites were obtained. These cores were processed, undecalcified sections prepared and stained with Stevenel blue/van Gieson's picric fuchsin, and histomorphometrically analyzed. Vital bone, connective tissue and marrow, and residual graft particles were reported as a percentage of the total core. RESULTS: A model system was described in humans and used to evaluate the healing response in the 3 treatment groups. Results concluded that mean vital bone present was 59.5% for BG-, 34.7% for DFDBA-, and 32.4% for C-treated sites. These differences were not statistically significant. However, the residual implant material was significantly higher in DFDBA-treated (13.5%) versus BG-treated sockets (5.5%). CONCLUSIONS: Although the differences in percent vital bone were not statistically significant among the 3 treatment groups in this pilot study, BG material was observed to act as an osteoconductive material which had a positive effect on socket healing at 6 to 8 months postextraction. Further research following implant placement in treated and control sockets is warranted to determine if bone implant contact is improved in BG-filled versus unfilled sockets.     

富血小板血浆与带血管肌筋膜在组织工程骨血管化中的作用

目的研究富血小板血浆（PRP）与带血管背阔肌肌筋膜在构建血管化组织工程骨中的作用价值。方法培养犬骨髓基质干细胞（BMSCs）,制备犬同种异体脱钙骨基质（DBM）,制备同一实验犬PRP。12只实验犬分为3组,每只犬的背部两侧分为ABCD 4个区, 左侧为A、B区,植入PRP/BMSCs/DBM;右侧为C、D区, 植入BMSCs/DBM。A、C区植入物用带血管背阔肌肌筋膜包裹,B、D区植入物用背部不带血管的浅筋膜包裹。于4、8、12周取出植入物行肉眼及组织学检查。结果成骨与血管化程度依次为A>B>C>D。结论PRP与带血管背阔肌肌筋膜均可促进组织工程骨的形成和血管化,两者有协同作用。     

Influence of platelet-rich plasma on bone regeneration: a histomorphometric study in rabbit calvaria

PURPOSE: The aim of this study was to evaluate whether local application of platelet-rich plasma (PRP) would induce bone regeneration in cranial defects on rabbits. MATERIALS AND METHODS: Twelve female New Zealand rabbits were used for this study. Two identical 10-mm-diameter bicortical cranial defects were created in each animal. One of the defects was grafted with PRP, while the contralateral was left unfilled as a negative control. Animals were sacrificed at 2, 4, 6, and 8 weeks after surgery, and biopsy specimens were evaluated histologically and histomorphometrically under light microscopy. Analysis of variance was used for statistical analysis. RESULTS: The histomorphometric evaluation showed more regenerated bone after local administration of PRP at 2 weeks (P > .05), 4 weeks (P < .05), and 6 weeks (P > .05). At week 8, new bone formation was comparable in both groups. CONCLUSION: In this animal model, local application of PRP in bone defects enhances healing significantly at 4 weeks.     

Bone remodeling around implants placed in fresh extraction sockets

The aim of the present experimental study was to evaluate the physiologic bone remodeling in beagle dogs following the placement of small-diameter (3.25 mm) implants in fresh extraction sites. Five 1-year-old beagle dogs that weighed approximately 10 to 13 kg each were used in this study. The third and fourth premolars (P3, P4) were used as experimental teeth, which were hemisected using a fissure bur; the distal roots were removed carefully using forceps. Implants (3.25-mm wide, 10- or 11.5-mm long) were placed in the fresh extraction sockets with the neck of the implant at the level of the buccal bone crest. The dogs were subsequently put to sleep according to the following schedule: one dog 15 days after implant placement, two dogs after 1 month, and the remaining two dogs after 3 months. The distance from the implant shoulder to the bone wall crest was measured at both the buccal and lingual sites. The width of the buccolingual bone crest was measured using a caliper. Assessments were made immediately after root extraction and at 2, 4, and 12 weeks after implant placement. The mean width of the buccolingual bone crest was 4.5 ± 0.5 mm at the time of root extraction. Subsequently, at 2, 4, and 12 weeks after implant placement, the buccolingual bone width was 4.1 ± 0.5 mm, 3.7 ± 0.3 mm, and 3.5 ± 0.7 mm, respectively. Two weeks after implant placement, the lingual bone crest was measured at 0.2 ± 0.3 mm from the implant shoulder, while the buccal bone crest was 0.3 ± 0.3 mm. After 4 weeks of healing, the mean distance from the implant shoulder to the lingual bone crest was 0.1 ± 0.9 mm, compared to 0.4 ± 0.9 mm for the buccal bone crest. After 12 weeks of healing, the bone crest at the lingual sites was -0.3 ± 0.5 mm from the implant shoulder, compared to 0.8 ± 0.3 mm at the buccal sites. The findings from this study show that although vertical bone remodeling was indeed observed, the mean vertical buccal bone resorption was 0.5 mm. It might be suggested, therefore, that the implant position along the lingual wall and the use of implants with a narrow diameter in relation to the extraction socket width play a key role in reducing the rate of vertical bone resorption at the buccal aspect of implants placed in fresh extraction sockets.     

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.     

The effect of simvastatin on remodelling of the alveolar bone following tooth extraction

Suppression of residual ridge resorption after tooth extraction is a hot spot in dental research. Recently, simvastatin was reported to influence bone turnover by stimulating bone formation. In this study, the effect of simvastatin application on residual ridge resorption following tooth extraction was investigated. Sixty male Wistar rats were randomly divided into experimental and control groups (n=30). Polylactic acid/polyglycolic acid copolymer carriers, with or without simvastatin, were implanted into extraction sockets of right mandibular incisors. The rats were killed at 1, 2, 4, 8 or 12 weeks after implantation. The relative height of the residual alveolar ridge was significantly greater in the experimental compared to the control group at 2, 4, 8 and 12 weeks. The bone mineral density in the experimental group was significantly higher than that in the control group at 4, 8 and 12 weeks. A larger newly formed bone island was observed in the experimental group at 4 weeks, and higher bone formation rate and quality were found than in the control group at different time points except 1 week. The findings indicate that local application of simvastatin would effectively preserve the residual alveolar bone by promoting bone formation in the extraction socket.     

Socket preservation using bovine bone mineral and collagen membrane: a randomized controlled clinical trial with histologic analysis

After tooth extraction, varying amounts of bone resorption occur because of qualitative and quantitative changes at the edentulous site of the alveolar process. The aims of this randomized controlled clinical trial were (1) to compare the postextraction changes in residual ridge dimensions during spontaneous healing with those during socket preservation, (2) to analyze the histologic and histomorphometric aspects of the grafted sockets, and (3) to compare probing procket depth (PPD) and clinical attachment level (CAL) changes at teeth adjacent to extraction sites. Forty-eight teeth were extracted from 41 patients referred for extraction of 1 or more maxillary or mandibular premolars or molars. The edentulous sites were randomly assigned to the control (EXT, extraction alone) or experimental groups (SP, extraction and socket preservation). In the SP group, the sockets were filled with bovine bone mineral and covered with porcine collagen membrane. At baseline and after 4 months, PPD, gingival recession (REC), and CAL were measured at teeth adjacent to the edentulous sites. The changes in ridge dimensions from baseline to 4 months were assessed on dental casts. At 4 months, bone was harvested from the grafted areas in the SP group and the edentulous areas in the EXT group. PPD, REC, and CAL were comparable between groups. However, from baseline to 4 months, the SP group showed significantly less reduction in ridge width (1.04 ± 1.08 mm vs 4.48 ± 0.65 mm, P < .001) and height (0.46 ± 0.46 mm vs 1.54 ± 0.33 mm, P < .001). Histologically, the grafted sockets exhibited various stages of bone maturation and formation without inflammatory responses. No significant difference in the mineralized and nonmineralized fractions was noted between the groups. Socket preservation using bovine bone mineral and porcine collagen membrane considerably limits the amount of horizontal and vertical bone resorption when compared with extraction alone.     

Evaluation of a prototype trilayer membrane (PTLM) for lateral ridge augmentation: an experimental study in the canine mandible

The objective of this animal study was to evaluate a biodegradable/bioresorbable prototype trilayer membrane (PTLM) consisting of two collagen layers and an internal polylactide layer for lateral ridge augmentation in conjunction with two different bone grafting materials: particulate autograft or deproteinized bovine bone mineral (DBBM). In four mongrel dogs, two lateral bone defects per side were created in the mandible. The four defects per dog were randomly subjected to the following grafting treatments 3 months later: 1. PTLM+DBBM, 2. PTLM+particulate autograft, 3. ePTFE membrane+DBBM, 4. ePTFE membrane+particulate autograft. After a healing period of 4 1/2 months, the dogs were sacrificed for histological and histomorphometrical analysis. Percentage calculations for areas showing bone regeneration within the former defect outline were 56.8% for PTLM+DBBM, 85.2% for PTLM+autograft, 52.3% for ePTFE+DBBM, and 96.9% for ePTFE+autograft (differences between autograft and DBBM sites were significant at P<0.01 to P<0.05). Measurements of ridge enlargement (horizontal bone gain) were also significantly better for autograft+ePTFE sites compared to the other three grafting treatments. Histology demonstrated for most PTLM sites a moderate infiltration of lymphocytes and plasma cells adjacent to empty spaces corresponding to polylactide fragments. In addition, these reactions appeared to provoke subsequent resorption of newly formed bone. No such findings were seen in ePTFE sites. The tested prototype membrane cannot be recommended for clinical application.     

Flap vs. “flapless” surgical approach at immediate implants: a histomorphometric study in dogs

Aim: To compare the remodeling of the alveolar process at implants installed immediately into extraction sockets by applying a flap or a “flapless” surgical approach in a dog model. Material and methods: Implants were installed immediately into the distal alveoli of the second mandibular premolars of six Labrador dogs. In one side of the mandible, a full‐thickness mucoperiosteal flap was elevated (control site), while contra‐laterally, the mucosa was gently dislocated, but not elevated (test site) to disclose the alveolar crest. After 4 months of healing, the animals were sacrificed, ground sections were obtained and a histomorphometric analysis was performed. Results: After 4 months of healing, all implants were integrated (n=6). Both at the test and at the control sites, bone resorption occurred with similar outcomes. The buccal bony crest resorption was 1.7 and 1.5 mm at the control and the test sites, respectively. Conclusions: “Flapless” implant placement into extraction sockets did not result in the prevention of alveolar bone resorption and did not affect the dimensional changes of the alveolar process following tooth extraction when compared with the usual placement of implants raising mucoperiosteal flaps. To cite this article:
Caneva M, Botticelli D, Salata LA, Souza SLS, Bressan E, Lang NP. Flap vs. “flapless” surgical approach at immediate implants: a histomorphometric study in dogs.
Clin. Oral Impl. Res. 21 , 2010; 1314–1319.
doi: 10.1111/j.1600‐0501.2009.01959.x     

Influence of platelet-rich plasma on osseous healing of dental implants: a histologic and histomorphometric study in minipigs

PURPOSE: In the present study the time course of local bone formation following the application of PRP during implant placement was evaluated histomorphometrically and histologically. MATERIALS AND METHODS: The mandibular premolars of 12 adult minipigs were removed surgically and 72 sites were prepared for implant placement. Before the implants (MK III, Replace, and MK III TiUnite) were placed, autogenous PRP (8 x 10(5) to 10 x 10(5) platelets/microL) was instilled into the host sites on the left side. The animals were sacrificed at 3, 6, and 12 weeks, and undecalcified ground sections were prepared. RESULTS: The histomorphometric evaluation showed significantly more bone-to-implant contact after topical PRP application in the early healing phase (6 weeks), which varied as a function of the distance from the implant surface (controls = 24.2% versus PRP = 44.21%; P = .013). At 12 weeks, the extent of osteoneogenesis was comparable in the 2 groups (controls = 51.3% versus PRP = 44.2%; P = .251). Statistical analysis revealed no significant interaction between implant surface type and PRP. DISCUSSION: Topical PRP application significantly increased the activity of bone regeneration at implant host sites during early healing. CONCLUSION: In the present study PRP was found to have a time- and site-dependent effect on peri-implant bone healing.     

Comparison of biomaterial implants in the dental socket: histological analysis in dogs

Background: Bone graft procedures have been used commonly in buco-maxillo-facial surgery. For this reason, many researchers have evaluated the bone substitutes.
Purpose: The present study evaluated soft and hard tissue reactions to two different hydroxyapatites HAs (synthetic HA and natural HA) and bioactive glass implanted into the sockets immediately after extraction.
Materials and Methods: First and third upper and lower premolars, on both sides, were extracted from six female dogs. The alveolar sockets were randomly assigned to four groups: Group 1 – control (unfilled), Group 2 – filled with synthetic hydroxyapatite, Group 3 – filled with bovine bone mineral (natural HA), and Group 4 – filled with bioactive glass. The animals were euthanized at 4 weeks ( n  = 2), 8 weeks ( n  = 2), and 28 weeks ( n  = 2) after extraction. The mandible and maxilla of each animal were removed for histological analysis to determine soft tissue reactions, newly formed bone, bone characteristics, and presence or absence of implanted materials.
Results: Most particles of synthetic hydroxyapatite had bone formation on their surface, although some particles showed a layer of fibrous connective tissue. The bovine bone mineral group exhibited particles partially replaced with bone formation. The bioactive glass group showed particles with a thin layer of calcified tissue, but was absent in some specimens, suggesting complete resorption.
Conclusion: All biomaterials had similar behavior. Bovine bone mineral, compared to synthetic hydroxyapatite and bioactive glass, showed a larger number of particles covered with osseous tissue. All biomaterials interfered with the socket repair process.     

骨形成蛋白与胶原膜联合应用促进即刻种植体周骨组织再生的实验研究

目的 比较单独应用胶原膜和胶原膜与人骨形成蛋白（ｈＢＭＰ）联合应用引民即刻种植体周骨缺隙骨再生的效果。方法 将复合有ｈＢＭＰ和ｈＢＭＰ的相同种植体分别植入１２只成年杂种狗下颌拨牙窝,覆盖胶原膜。于术后２、４、８、１２周每次处死狗３只,取格,扫描电子显微镜观察。结果 在种植体周骨缺隙部,有ｈＢＭＰ组２周时即有大量新骨形成,８周时骨缺隙完全由成熟的骨质充填,而无ｈＢＭＰ组,１２周时种植体周骨缺隙由仍未