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。     

可吸收胶原膜在即刻种植中引导骨组织再生作用的研究

目的:通过动物实验研究可吸收胶原膜在即刻种植骨缺损区引导骨组织再生的作用。方法:8只实验用犬,拔除双侧下颌第二、三、四前磨牙,每个拔牙窝植入1枚种植体,并在种植体颈部对应牙槽骨上制备半环状骨缺损,将每只实验犬口内的6处骨缺损随机分为3组,每组两处,并给予不同处理。A组:骨缺损中植入珊瑚羟基磷灰石,并用可吸收胶原膜覆盖;B组:骨缺损中单纯植入珊瑚羟基磷灰石;C组:骨缺损中不植入任何材料,作为空白对照组。3个月后处死所有实验动物,制作含单个种植体的骨标本,进行大体观察、生物力学测定、组织形态学观察及测定。结果:3组标本骨缺损区均可见新骨生成,A组种植体颈部骨缺损区无软组织长入,新生骨量多,骨质成熟,成骨效果最好;B组次之,部分标本骨缺损区有软组织长入,新生骨量及骨质均不如A组。C组最差。结论:可吸收胶原膜生物相容性良好,可降解,可阻止软组织向骨缺损区长入,对骨组织再生有促进作用。     

即刻种植后采用GBR术和植入PRF对骨结合影响的实验研究

目的：比较研究即刻种植后用GBR术和植入PRF对种植体周骨缺损区的成骨能力。方法：以成年Bea-gle犬为实验动物,拔除犬双侧下颌P2、 P3、 P4牙,即刻植入种植体,所植入的种植体距近中根拔牙窝的近中壁有3～4mm的骨缺损间隙,采用半口自身对照,一侧行即刻种植＋GBR （A组）,一侧即刻种植＋PRF （B组）,术后三个月处死动物,取下带有种植体的下颌骨标本,进行组织学观察。对两组种植体周围的骨结合率和新骨生成率运用统计软件SPSS13.0进行统计学分析。结果： A组、 B组骨缺损处3个月时均被新骨充填,两组种植体周围的骨结合率和新骨生成率差异无统计学意义。结论：限于本研究中,即刻种植术中采用GBR和植入PRF对骨缺损区的引导骨再生效果相同。     

Gel-HA-M/PRP复合材料对种植体周围骨缺损修复的实验研究

目的:观察明胶-羟基磷灰石-米诺环素(Gel-HA-M)纳米复合物与富血小板血浆(platelet-rich plasma,PRP)复合(GEL-HA-M/PRP)修复种植体周围骨缺损的效果,探讨其作为种植体周围骨缺损修复材料的可行性.方法:普通健康杂种犬6只,拔除双侧下颌第二、三、四前磨牙,3个月后每侧拔牙处植入3枚...     

富血小板血浆在种植体周围骨缺损修复中的实验研究

目的:探讨富血小板血浆(platelet-richplasma,PRP)、PRP复合骨诱导活性材料(osteoinduction active material,OAM)对种植体周围骨缺损修复的作用。方法:Beagle犬4只,拔除每只犬一侧下颌第一、二前磨牙及其双侧下颌第四前磨牙作为实验牙位。3个月后拔牙处植入种植体,每只犬共植入3颗种植体,第一、二前磨牙牙位植入1颗种植体为对照组,对侧第四前磨牙牙位植入1颗种植体为实验A组,同侧第四前磨牙牙位植入1颗种植体为实验B组。种植术中同期制备种植体周围骨缺损并植入相应骨移植材料:A组植入PRP/OAM;B组植入PRP/磷酸三钙;对照组植入磷酸三钙。种植术后8、16周处死动物,进行组织学观察,测量种植体周围骨密度,采用SPSS13.0软件对数据进行单因素方差分析。结果:8周时,实验A组新骨与种植体形成区段性骨结合;实验B组种植体边缘可见新骨形成,但量较少;对照组种植体边缘为纤维性界面。8周时骨密度测量,各组间骨密度差异无统计学意义。16周时,实验A组可见哈佛系统,实验A、B组新骨与种植体形成骨整合;对照组仅为纤维性结合。16周时骨密度测量,两实验组骨密度均显著高于对照组。结论:PRP及PRP/OAM可促进种植体周围骨缺损修复。     

纳米羟基磷灰石修复种植体周围骨缺损的实验研究

目的:探讨纳米羟基磷灰石材料在种植修复中的作用.方法:将纳米羟基磷灰石植入钛种植体周围的骨缺损区,观察种植体与骨界面的结合形式和程度.结果:纳米羟基磷灰石修复钛种植体骨缺损处实现良好的骨结合.结论:纳米羟基磷灰石材料的使用在实现钛种植体与周围健康骨组织的骨结合过程中起着重要的作用.     

富血小板血浆与骨诱导活性材料复合物促种植体周骨缺损修复的实验研究

目的:观察富血小板血浆(platelet-rich plasma,PRP)、PRP复合骨诱导活性材料(osteoinduction active material,OAM)对种植体周围骨缺损的修复效果,探讨其作为种植体周围骨缺损修复材料的可行性.方法:Beagle犬4只,拔除双侧下颌第一、二、四前磨牙,3个月后植入种植体,制备种植体周围骨缺损并植入相应骨移植材料.A组植入PRP/ OAM,B组植入PRP,磷酸三钙,对照组植入磷酸三钙.种植术后8、16周各处死2只动物,进行组织学观察,能谱分析种植体-新骨界面Ca2+含量,采用SPSS13.0软件包对数据进行单因素方差分析.结果:8周时,实验A组新骨与种植体形成区段性骨结合;实验B组种植体边缘可见新骨形成,但量较少;对照组种植体边缘为纤维性界面.16周时,实验A组可见哈佛系统,实验A、B组新骨与种植体形成骨整合;对照组为纤维性结合.能谱分析显示,8、16周时各组间钙含量百分比均存在显著差异.实验A组最高,实验B组其次,对照组最低.结论:PRP及PRP/OAM应用于种植体周围骨缺损中,可以促进骨缺损的修复,并形成理想的种植体-骨结合界面.     

即刻种植种植体周围骨缺损的Beagle犬动物模型建立

目的:评估即刻种植后种植体周围骨缺损植骨与否对骨结合的影响,建立一种符合即刻种植种植体周围骨缺损特点的动物模型。方法:以成年Beagl e犬为实验动物,拔除犬双侧下颌P2、P3、P4牙。于远中根拔牙窝的远中距牙根间隔5-6mm处预备种植窝,即刻植入种植体。植入种植体后保证沿下颌骨长轴向骨缺损范围达3-4mm。骨缺损区不植入骨粉,直接用胶原膜覆盖为实验组。骨缺损区植入骨粉并覆盖胶原膜为对照组。于术后3个月末处死动物取材,进行组织学观察。结果:X线观察:实验组与对照组缺损处到3个月时均被新生骨充填。组织切片染色镜下观察:实验组与对照组骨缺损处可见大量骨细胞,骨改建基本完成。结论:种植体与拔牙窝内壁之间的3-4mm范围骨间隙即使不植骨,也会有新骨生成、并且可以与种植体表面发生骨结合。成功构建了与临床即刻种植骨缺损相似,并可作为研究即刻种植骨界面骨性结合的实验动物模型。     

骨诱导活性材料复合富血小板血浆修复犬种植体周围骨缺损

目的从组织学角度评价骨诱导活性材料(osteoinduction active material,OAM)复合富血小板血浆(platelet-rich plas-ma,PRP)对种植体周围骨缺损的修复效果。方法Beagle犬4只,拔除下颌1、2、4前磨牙。每只犬左右两侧实验牙位随机分为实验侧和对照侧,实验侧第4前磨牙牙位为实验A组,第1、2前磨牙牙位为实验B组,对照侧第1、2前磨牙牙位为对照组。3个月后植入种植体,制备种植体周围骨缺损。实验A组骨缺损区植入OAM/PRP;B组植入OAM;对照组植入磷酸三钙。8、16周分别处死动物2只,进行组织学观察,能谱分析种植体-新骨界面Ca含量。结果8周时,A、B组新骨与种植体形成区段性骨结合,对照组种植体边缘为纤维性界面。各组间种植体-新骨界面Ca含量存在显著性差异。16周时,实验A、B组可见哈佛氏系统,新骨与种植体形成骨整合,对照组为纤维性结合。实验各组Ca含量均显著高于对照组。结论OAM及PRP/OAM能促进种植体周围骨缺损修复。     

即刻种植骨结合式牙种植体的实验研究

目的 通过改进的犬却刻种植研究模型,验证即刻种植的可行性,探求适宜的种植体周围骨缺损处理方式。方法 在骨缺损区内分别植入脱钙冻干异体骨,骨形成蛋白复合的异体松擀骨,以空白植入为对照,观察不同时间和部位骨缺损的修复程度及种植体骨结构情况。结果 ＤＦＤＢＡ组１２周,ＢＭＰ复合骨组８周骨缺损修复完成,种植体骨结合形成;无材料植入组骨缺损仅修复的３／５。结论种植体周围骨缺损经过适当处理,可形成良好骨结合而     

Platelet-rich plasma may not provide any additional effect when associated with guided bone regeneration around dental implants in dogs

OBJECTIVE: The aim of this study was to evaluate histometrically bone healing in surgically created dehiscence-type defects around titanium implants treated with an association of platelet-rich plasma (PRP) and guided bone regeneration (GBR). MATERIALS AND METHODS: Ten male adult mongrel dogs were used, from which the three low premolars (P2, P3, P4) and the first molar were extracted. Three months after teeth extraction, two implant sites were bilaterally drilled, buccal bone dehiscences were created and four titanium implants were placed. Dehiscences were randomly assigned to the following groups: (1) PRP, (2) GBR, (3) PRP+GBR and (4) control. After 3 months, the animals were sacrificed and the implants and adjacent hard tissues were processed for undecalcified sections. Bone-to-implant contact (BIC), bone density within the limits of implant threads (BW), bone density (BD) and new bone area (BA) in a zone lateral to the implant corresponding to bone defects were obtained and measured. RESULTS: Intergroup analysis (two-way ANOVA -alpha=5%) demonstrated that when PRP was utilized,no differences were observed for all parameters (P>0.05). However, significant differences were observed for BIC and BW toward membrane-treated groups (P<0.05). CONCLUSION: Within the limits of this study, it was concluded that PRP does not exert additional effects on bone healing in bone defects created around dental implants and treated by GBR.     

Regenerative potential of platelet-rich plasma added to xenogenic bone grafts in peri-implant defects: a histomorphometric analysis in dogs

BACKGROUND: The purpose of this investigation was to evaluate the regenerative influence of platelet-rich plasma (PRP) added to xenogenic bone grafts on bone histomorphometric parameters in a dog model. METHODS: Ninety endosseous dental implants were inserted in the mandibles of nine hound dogs. Mesial and distal 3-wall peri-implant defects were surgically created adjacent to the implants. Defects were randomly assigned to three groups: demineralized freeze dried bone with platelet-rich plasma (DFDB + PRP), DFDB alone, and no treatment (NT). Animals were sacrificed at 1, 2, and 3 months according to a previously established randomization schedule, and specimens were subjected to histomorphometric analysis. Percentages of bone area inside the implant threads (BiIT), bone-to-implant contact (BIC), and bone area outside implant threads (BoIT) were recorded. Treatment effects were evaluated using analysis of variance models. RESULTS: The effect of the three treatments on the outcome measures did not differ significantly by healing time (P > 0.05 for the healing time by treatment interaction). However, the average (standard deviation) percentage of BIC and BoIT was significantly different between the treatment groups. In particular, the average percentage of BIC differed between peri-implant defects treated with DFDB + PRP (33.8% [11.0]) and those treated with DFDB alone (28.5% [10.8]; P = 0.042), as well as those in the NT group (27.9% [11.0]; P = 0.024). Furthermore, the average percentage of BoIT differed significantly between defects treated with DFDB + PRP compared to defects in the NT group (51.6% [12.2] versus 43.3% [10.3]; P = 0.005). There was borderline evidence to suggest that the average percentage of BiIT and BIC was significantly different depending on the length of the healing time (P = 0.054 and P = 0.085, respectively). CONCLUSION: This study found that the addition of PRP to xenogenic bone grafts demonstrated a low regenerative potential in this animal model.     

Effect of osteoblast cell culture on the bone implant contact

Abstract

Purpose. The aim of this study is to acquire an ideal bone implant contact under the cover of osteogenic effect of osteoblasts derived from Mesenchymal Stem Cells (MSCs). Materials and methods. Thirty dental implants were used for this study. Implants were placed in sheep mandibles and defects were created 4 mm coronally in the dental implants. These defects were filled with Platelet Rich Plasma (PRP) in one group and with PRP + Osteoblast Cell Culture (OCC) in another group. No procedure was conducted on the control group defects (empty defect group). Eight weeks later, osseointegration was investigated with Bone Implant Contact (BIC) measurements histomorphologically. Data were checked statistically. Results. The variation of BIC rates between Empty Defect Group and PRP groups was significant (p <0.05). The BIC rate of the PRP group was higher than that of the Empty Defect Group. The variation of BIC rates between Empty Defect Group and PRP + OCC groups was significant (p <0.05). The BIC rate of the PRP + OCC group was higher than that of the Empty Defect Group. The variation of BIC rates between PRP and PRP + MSC groups was significant (p<0.05). The BIC rate of the PRP + OCC group was higher than that of the PRP group. At the end of the 8-week healing period, it was observed that the percentage of BIC was highest in the PRP + OCC group. Conclusions. Implant–bone connection was better in the OCC?PRP group compared with the PRP group and the empty defect group. The use of OCC-PRP combination was effective on healing. The BIC value was increased significantly by OCC.     

Platelet-rich plasma does not improve bone regeneration around peri-implant bone defects--a pilot study in dogs

The purpose of the present study was to evaluate the influence of platelet-rich plasma (PRP) on bone regeneration in dehiscence-type bone defects around dental implants. Ten male adult mongrel dogs were used. Three months after teeth extractions, an osteotomie for implantation and a buccal dehiscence defect were prepared on both sides of the jaws. Two dental implants with machined surfaces were placed on each implant site of the mandible. Dehiscences were randomly assigned to the following groups: (1) test (PRP) and (2) control. After 3 months animals were sacrificed; implants and adjacent hard tissues were processed for undecalcified sections. Bone-to-implant contact (BIC), bone density (BD) within the limits of implant threads, bone density (BO) and new bone area (NB) in a zone lateral to the implant, corresponding to bone defects, were obtained and measured. Inter group analysis (paired Student's t-test, alpha = 5%) demonstrated no statistically significant differences for any of the parameters when PRP was used (P > 0.05). Within the limits of the present study, it was concluded that platelet-rich plasma alone did not enhance bone regeneration for peri-implant defects.     

Tissue-engineered injectable bone regeneration for osseointegrated dental implants

The present study investigated a correlation between osseointegration in dental implants and an injectable tissue-engineered bone, using mesenchymal stem cells (MSCs) and platelet-rich plasma (PRP). Initially, the teeth in the mandible region were extracted and the healing period was 1 month. Bone defects on both sides of the mandible were prepared with a trephine bar. The defects were implanted with graft materials as follows: PRP, dog MSCs (dMSCs), and PRP, autogenous particulate cancellous bone and marrow (PCBM), and control (defect only). Two months later, the animals were evaluated by histology, and at the same time dental implants were installed. Two months later, the animals were sacrificed and nondecalcified sections were evaluated histologically and histometrically. According to the histological observations, the dMSCs/PRP group had well-formed mature bone and neovascularization, compared with the control (defect only) and PRP groups, as was the same for the PCBM group. A higher marginal bone level was observed around implants with PRP, PCBM, and dMSCs/PRP compared with the control. Furthermore, the values describing the amount of bone-implant contact (BIC) at the bone/implant interface were significantly different between the PRP, PCBM, dMSCs/PRP, and control groups. Significant differences were also found between the dMSCs/PRP and control groups in bone density. The findings of this experimental study indicate that the use of a mixture of dMSCs/PRP results in good results such as the amount of BIC and bone density comparable with that achieved by PCBM.     

Bone regeneration of dental implant dehiscence defects using a cultured periosteum membrane

OBJECTIVES: This study aimed to demonstrate the feasibility of a cultured periosteum (CP) membrane for use in guided bone regeneration at sites of implant dehiscence. MATERIAL AND METHODS: Four healthy beagle dogs were used in this study. Implant dehiscence defects (4 x 4 x 3 mm) were surgically created at mandibular premolar sites where premolars had been extracted 3 months back. Dental implants (3.75 mm in diameter and 7 mm in length) with machined surfaces were placed into the defect sites (14 implants in total). Each dehiscence defective implant was randomly assigned to one of the following two groups: (1) PRP gel without cells (control) or (2) a periosteum membrane cultured on PRP gel (experimental). Dogs were killed 12 weeks after operation and nondecalcified histological sections were made for histomorphometric analyses including percent linear bone fill (LF) and bone-to-implant contact (BIC). RESULTS: Bone regeneration in the treatment group with a CP membrane was significantly greater than that in the control group and was confirmed by LF analysis. LF values in the experimental and the control groups were 72.36+/-3.14% and 37.03+/-4.63%, respectively (P<0.05). The BIC values in both groups were not significantly different from each other. The BIC values in the experimental and the control groups were 40.76+/-10.30% and 30.58+/-9.69%, respectively (P=0.25) and were similar to native bone. CONCLUSION: This study demonstrated the feasibility of a CP membrane to regenerate bone at implant dehiscence defect.     

Simultaneous implant placement and bone regeneration around dental implants using tissue-engineered bone with fibrin glue, mesenchymal stem cells and platelet-rich plasma

This study was undertaken to evaluate the use of tissue-engineered bone as grafting material for alveolar augmentation with simultaneous implant placement. Twelve adult hybrid dogs were used in this study. One month after the extraction of teeth in the mandible region, bone defects on both sides of the mandible were induced using a trephine bar with a diameter of 10 mm. Dog mesenchymal stem cells (dMSCs) were obtained via iliac bone biopsy and cultured for 4 weeks before implantation. After installing the dental implants, the defects were simultaneously implanted with the following graft materials: (i) fibrin, (ii) dMSCs and fibrin (dMSCs/fibrin), (iii) dMSCs, platelet-rich plasma (PRP) and fibrin (dMSCs/PRP/fibrin) and (iv) control (defect only). The implants were assessed by histological and histomorphometric analysis, 2, 4 and 8 weeks after implantation. The implants exhibited varying degrees of bone-implant contact (BIC). The BIC was 17%, 19% and 29% (control), 20%, 22% and 25% (fibrin), 22%, 32% and 42% (dMSCs/fibrin) and 25%, 49% and 53% (dMSCs/PRP/fibrin) after 2, 4 and 8 weeks, respectively. This study suggests that tissue-engineered bone may be of sufficient quality for predictable enhancement of bone regeneration around dental implants when used simultaneous by with implant placement.     

同种异体骨骨粉联合PRP与自体髂骨移植在治疗颌骨骨缺损的对比研究

目的　观察和比较同种异体骨骨粉联合PRP与自体髂骨移植在治疗颌骨骨缺损中的疗效和差异。方法：将22例上颌切牙/侧切牙和尖牙区牙缺失、骨缺损患者随机分为A组和B组,各11例。两组患者分别采用PRP联合同种异体骨骨粉或自体髂骨移植填充颌骨骨缺损区域。以1个月、2个月、3个月随访时原缺损区域的CT值数据为依据,对照正常骨质,评价填充区域内骨生长变化情况。在行二期牙种植手术时取骨质行病理分析,评价骨质质量,并测量种植体的ISQ值,了解种植体初始稳定性,评估新生骨对种植体的把持能力和生物力学。结果：在基线资料具有可比性的前提下,A、B两组骨缺损区域植骨术后组内比较的CT值各观察点上数据无统计学意义（A组P=0.98;B组P=0.14）,A组CT值高于正常骨质（P=0.02）,而B组CT值与正常骨质无显著差异性（P=0.51）。A、B两组牙种植术后的ISQ值比较无统计学意义（P=0.87）。新生骨病理切片提示A组新生骨质和纤维组织错杂,内有较多颗粒状钙化,B组标本为典型的松质骨,纤维组织极少,无钙化杂质夹杂。结论：PRP联合同种异体骨骨粉填充骨缺损可以避免额外有创操作和手术切口,更加容易被临床治疗接受,而自体髂骨移植有更好的组织相容性和骨生长,两种方法成骨在进行牙种植时均体现出良好的生物力学性质,不影响种植体的初始稳定。根据适应症和临床实际需要选择PRP联合同种异体骨骨粉或自体髂骨移植。