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。     

PRP及PRP/OAM对种植体周围骨缺损修复的实验研究

目的探讨富血小板血浆(PRP)以及PRP复合骨诱导活性材料(PRP/OAM)对种植体周围骨缺损修复的作用。方法选取成年Beagle犬4只,体质量10~13 kg,每只犬左右两侧下颌第四前磨牙牙位随机分为A组和B组,与B组同侧的第一、二前磨牙牙位作为对照组。A组种植体周围骨缺损区植入PRP/OAM,B组植入PRP/磷酸三钙,对照组植入磷酸三钙。采用能谱分析各组种植体-新骨界面Ca~(2+)含量,同时观察各组种植术后8、16周组织学形态。结果 A组和B组种植术后8、16周时种植体部位骨表面Ca~(2+)含量均明显高于对照组(P<0.05);A组种植术后8、16周时种植体部位骨表面Ca~(2+)含量为(26.01±3.28)%和(44.10±7.11)%,明显高于B组(P<0.05);种植术后8周,A组新骨与种植体形成区段性骨结合,B组种植体边缘可有新骨形成,对照组种植体边缘为纤维性界面;种植术后16周,A组和B组新骨与种植体形成骨整合,对照组仅为纤维性结合。结论 PRP及PRP/OAM在种植体周围骨缺损修复中,能有效促进骨缺损修复。     

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.     

骨诱导活性材料修复犬种植体周围骨缺损的实验研究

目的:通过动物实验,探讨骨诱导活性材料(osteoinduction active material,OAM)对种植体周围骨缺损的修复能力.为临床应用提供实验依据.方法:Beagle犬4只,拔除双侧下颌第一、二前磨牙.将每只犬的两侧实验牙位随机分为实验侧和对照侧.拔牙后3个月植入种植体,建立种植体周围骨缺损模型.实验组种植体周围骨缺损区植入OAM,对照组植入磷酸三钙.于植入后第8、16周分别处死2只动物,进行组织学、扫描电镜观察.测量骨密度.能谱分析种植体一新骨界面Ca2+含量,采用SPSS13.0软件包对数据进行t检验.结果:8周时,实验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.实验组与对照组骨密度差异无统计学意义(P＞0.05),实验组种植体一新骨界面Caz+含量(22.16±3.33)显著高于对照组(3.13±2.44)(P＜0.05).16周时,实验组新生骨与种植体形成骨整合,对照组为纤维性结合.实验组骨密度显著高于对照组(P＜0.051,实验组种植体一新骨界面Ca2+含量(42.23±6.20)显著高于对照组(10.40±3.12)(P＜0.05).结论:OAM能促进种植体周围骨缺损修复,并促进种植体一骨界面形成较完善的骨整合.     

富血小板血浆修复种植体周围骨缺损的实验研究

目的探讨富血小板血浆(platelet-rich plasma,PRP)修复种植体周围骨缺损的能力。方法Beagle犬4只,拔除单侧下颌1、2、4前磨牙作为实验牙位。3个月后植入种植体,其周围制备骨缺损并植入相应骨移植材料:实验组植入PRP/磷酸三钙(tricalcium phosphate,TCP);对照组植入TCP。8、16周分别处死动物2只,进行组织学、扫描电镜观察,观察新骨形成和种植体-新骨界面情况,能谱分析种植体-新骨界面Ca含量。结果8周及16周通过肉眼及组织学观察,实验组修复效果优于对照组,种植体-新骨界面Ca含量均高于对照组,差异有显著性(P<0.05)。结论PRP/TCP作为修复种植体周围骨缺损的骨移植材料具有可行性。     

BMSCs复合PRP修复牙种植体周围骨缺损的实验研究

目的:探讨骨髓基质细胞(bone marrow stromal cells,BMSCs)复合富血小板血浆(platelet-rich plasma,PRP)修复牙种植体周围骨缺损的可行性。方法:拔除6只Beagle犬双侧下颌8颗前磨牙,术后1个月抽取犬骨髓,采用全骨髓贴壁法培养BMSCs,并向成骨细胞诱导,将BMSCs与PRP、β-磷酸三钙(β-tricalcium phosphate,β-TCP)分别复合形成组织工程化复合物。术后2个月,在实验犬每侧下颌缺牙区分别植入BLB4mm×11mm种植体4颗,同时在每个种植体的近中制造4mm×4mm×5mm大小的骨缺损,分别植入BMSCs-PRP复合凝胶、自体骨、BMSCs-β-TCP复合物以及空白对照,分别于种植术后4、8、12周各处死2只犬,行大体、环境扫描电镜及组织学检查,观察各个时期各组骨缺损区的成骨情况以及新生骨与种植体间骨结合情况。结果:3个实验组在术后4、8、12周均有不同程度的骨组织再生,而空白对照组只有少量骨组织再生。各个时期内扫描电镜观察显示BMSCs-PRP组新生骨与种植体间的骨结合较其他三组多。结论:BMSCs-PRP复合凝胶是一种良好的骨修复材料,具有促进新骨形成及种植体骨结合的效应。     

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。     

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。     

浓缩生长因子促进犬种植体周围骨缺损修复的实验研究

目的:探讨浓缩生长因子(concentrate growth factors,CGF)促进犬种植体周围骨缺损修复的能力。方法:Beagle犬4只,拔除双侧下颌第一前磨牙作为实验牙位。3个月后,待拔牙窝内骨组织基本成熟后植入种植体,其周围制备骨缺损(外侧壁制备深4 mm,颊舌及近远中向各1 mm的环行骨缺损)并植入骨移植材料;随机选取实验动物的左右侧下颌第一前磨牙,分别作为实验组和对照组,实验组植入CGF与磷酸三钙(tricalcium phosphate,TCP)的混合物;对照组植入TCP。8、16周后分别处死动物2只,进行X线、组织学观察,能谱分析种植体-新骨界面钙含量。采用SPSS13.0软件包对数据进行统计学分析。结果:8周及16周时,肉眼及组织学观察发现,实验组修复效果显著优于对照组,种植体-新骨界面钙含量均高于对照组,差异显著(P<0.05)。结论:CGF能够促进犬种植体周围骨缺损的修复,缩短骨整合时间,提高愈合质量。     

骨髓浓缩物（BMAC）对牙种植体周成骨结构影响的显微影像学分析

目的：利用Micro－CT图像分析骨髓浓缩物（BoneMarrowAspirateConcentrate,BMAC）对牙种植体周骨缺损的成骨结构影响。方法：选用健康成年杂种犬6只,拔除每只犬双侧下颌第三和第四前磨牙（P3和P4）作为实验牙位。3个月后在每只犬拔牙处植入4颗种植体,同期在种植体近中造箱状骨缺损,选2处骨缺损移植骨髓浓缩物（BMAC组）,另2处分别移植自体牙槽骨（AB组）和空白明胶海绵（对照组）。术后第4、12周各处死3只实验犬,标本行Micr0－CT扫描重建,分析缺损区内的骨形态学参数。结果：植入后第4周,骨髓浓缩物组（BMAC组）和自体牙槽骨组（AB组）的Tb．Sp值低于对照组,有统计学意义（P〈0．05）。结论：骨髓浓缩物可以缩短骨再生时间,术后第4周成骨质量优于自体牙槽骨;Micro－CT可有效分析种植体周围骨小梁空间结构。     

牙种植体周围骨内神经感受功能的初步研究

目的:观察骨结合牙种植体周围骨内神经末梢的分布特点,研究种植体潜在本体感觉功能随时间的变化趋势,探讨非负载种植体外周神经反馈通路重建的程度及时效过程。方法:雄性Beagle犬3只,拔除双侧下颌第二前磨牙至第一磨牙,拔牙窝愈合3个月。设计植入12颗骨内种植体,每只犬4颗作为一组,分为种植后1周组、种植后6周组和种植后12周组。采用PowerLab多导生理记录仪对种植体施加电脉冲刺激,并利用Chart5 For Windows软件同步记录刺激种植体诱发的下牙槽神经感觉动作电位曲线图。同期处死动物,收集种植体骨组织标本,采用免疫组化法进行组织学观察。应用SPSS17.0软件包对实验数据进行统计学分析。结果:观察期内种植体留存率为100%。不同时间组的神经电生理检测结果比较显示,在不同刺激强度下,植入6周和12周的种植体诱发的神经动作电位幅值无显著差异,而植入1周的种植体诱发的神经动作电位幅值明显小于前两者,具有显著差异。组织学观察证实,各组种植体周围骨组织内均存在少量神经末梢结构。结论:牙种植体周围骨组织内存在少量神经末梢结构,这些神经元能够对施加在种植体的刺激信号产生应答,进而诱发动作电位沿下牙槽神经传导至中枢,...     

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...     

Endosseous titanium implants during and after orthodontic load ‐ an experimental study in the dog

An experiment was carried out to determine whether endosseous titanium implants (Brånemarks®) retain their clinical stability throughout a 26‐week period of continuously applied force (2 N) and what kind of marginal peri‐implant bone changes occur in the process. For this purpose 6 premolars (P3: mandible/maxilla and P4: mandible) were extracted from each of 2 foxhounds, and 12 implants (6 per dog) were positioned in the edentulous maxillary and mandibular areas after the alveolar healing period. Following a 25‐week implant healing period, 8 fixtures (P3 areas) were used as anchoring elements for distalization of the 2nd premolars over a period of 26 weeks: 4 implants served as a control group (P4areas of the mandible). There were no clinical or histological signs of implant dislocation after the load application period. In the presence of mild peri‐implant gingivitis, no increase was found in the incidence of marginal bone resorption adjacent to the loaded implants compared with the non‐loaded implants. In the absence of marginal resorption, subperiosteal bone apposition was detected especially around the test implants in the mandible. This suggests that endosseous titanium implants are suitable as anchoring units for longer‐term orthodontic tooth movements. The applied force may moreover induce marginal bone appositions adjacent I to the implants.     

Hybrid Implant: A Novel Implant System

Introduction

Replacement of missing tooth has evolved from removable dentures to fixed dentures and recently to dental implants. The need of sufficient bone around the endosseous implant is critical for the success of the implant. The present study was aimed to evaluate the efficacy of a novel implant (HYBRID IMPLANT-submitted for patency) for replacement of the missing teeth.

Materials and methods

1. Research design A prospective research design with a follow up after 1st week ,2nd week ,3rd week,1st month ,3rd month,6th month and 1st year postoperatively. 2. Sampling method Population: All patients who reported for replacement of missing teeth. Inclusion criteria 1. All patients above the age group of 16years 2. Patients who need replacement of single or multiple teeth in the anterior or posterior region of the maxilla and mandible. Exclusion criteria 1. Medically compromised patients. 2. Patients having craniofacial syndromes. 3. Sample size 5 patients were selected taking into consideration the inclusion and exclusion Criteria. Results PAIN All the patients were non symptomatic during the 1st month to 1st year postoperative periods.

Mobility

We experienced mobility during the 1st and 2nd postoperative periods where the implants were inserted in the mandibular molar region.

Bone loss

Radiographic assessment showed no bone loss during the postoperative periods.

Conclusion

The novel implant (hybrid implant) showed good stability and minimum patient discomfort during one year postoperative period evaluation. The implant system leads to new prospect in the field of prosthetic rehabilitation.     

Re-osseointegration on rough implant surfaces previously coated with bacterial biofilm: an experimental study in the dog

OBJECTIVE: The purpose of the study was to investigate whether osseointegration can occur on rough implant surfaces that previously had been coated with bacterial biofilm. MATERIALS AND METHODS: The premolars on both sides of the mandible in four beagle dogs were extracted. Following 3 months healing, three titanium implants Ti-Unite, Nobel Biocare were partially inserted in the left side of each mandible. Some threads protruded from the tissues into the oral cavity. Plaque accumulated on the exposed part of the implant. Following a 5-week healing period, the contaminated parts of each implant were treated using three different techniques: (1) swabbing with citric acid for 30 s followed by rinsing with physiological saline, (2) cleansing with a toothbrush and physiological saline for 1 min, and (3) swabbing with 10% hydrogen peroxide for 1 min followed by rinsing with physiological saline. The treated implants and one pristine implant (control) were installed to the full implant length on the contralateral sides of the mandibles. Following 11 weeks of healing, the dogs were sacrificed and biopsies were obtained. Ground sections were prepared for histomorphometric analysis. RESULTS: All treatment modalities were associated with direct bone-to-implant contact on the portion of implant surface previously exposed to the oral environment. CONCLUSIONS: The results demonstrate that rough surfaces, which were plaque contaminated and cleaned by different methods, can re-osseointegrate.     

The effect of platelet-rich plasma upon implant stability measured by resonance frequency analysis in the lower anterior mandibles

Abstract: Using a one‐stage surgical protocol, a total of 34 Brånemark Mk‐III Ti‐Unite implants with a length of 13 mm and a diameter of 3.75 mm were inserted in 10 edentulous mandibles. Of these, seven patients received four and three patients two interforaminal implants. All implants were followed with repeated stability measurements by means of resonance frequency analysis at different time interval: 0, 4, 8, 12, 16, 20, 24, 28, 32, 36, 40, 44 days. In quadrant III platelet‐rich plasma (PRP) was instilled locally before implant placement, while no PRP was added in quadrant IV to serve as control group (split‐mouth design). Results showed no statistically significant difference between the two groups. Nonetheless, both groups (PRP+control) showed a highly significant reduction of the implant stability quotient (P<0.001) between days 0 and 4. However, no difference was noted between the two groups after day 4, it may be concluded that the instillation of PRP during implant placement in the lower anterior mandible did not add additional benefit.     

Bone healing at implants with a fluoride-modified surface: an experimental study in dogs

OBJECTIVES: The aim of the present experiment was to study early stages of osseointegration to implants with a fluoride-modified surface. MATERIAL AND METHODS: Six mongrel dogs, about 1-year old, were used. All mandibular premolars and the first mandibular molars were extracted. Three months later, mucoperiosteal flaps were elevated in one side of the mandible and six sites were identified for implant placement. The control implants (MicroThread) had a TiOblast surface, while the test implants (OsseoSpeed) had a fluoride-modified TiOblast surface. Both types of implants had a similar geometry, a diameter of 3.5 mm and were 8 mm long. Following installation, cover screws were placed and the flaps were adjusted and sutured to cover all implants. Four weeks after the first implant surgery, the installation procedure was repeated in the opposite side of the mandible. Two weeks later, biopsies were obtained and prepared for histological analysis. The void that occurred between the cut bone wall of the recipient site and the macro-threads of the implant immediately following implant installation was used to study early bone formation. RESULTS: It was demonstrated that the amount of new bone that formed in the voids within the first 2 weeks of healing was larger at fluoride-modified implants (test) than at TiOblast (control) implants. It was further observed that the amount of bone-to-implant contact that had been established after 2 weeks in the macro-threaded portion of the implant was significantly larger at the test implants than at the controls. CONCLUSION: It is suggested that the fluoride-modified implant surface promotes osseointegration in the early phase of healing following implant installation.     

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.     

Osseointegration on implant surfaces previously contaminated with plaque. An experimental study in the dog

This study investigated whether osseointegration can occur on a surface which had previously been coated with dental plaque. The mandibular premolar regions of four young adult Labrador dogs were used for the study. The lower premolars (P1, P2, P3, and P4) were extracted on either side of the mandibles. Following a 12-week healing period, three 3.75 mm x 13 mm commercially pure titanium implants (Nobel BiocareAB, Gothenburg, Sweden) were partially inserted in one side of each mandible. This resulted in some threads protruding from the tissues into the oral cavity. Plaque was allowed to accumulate on the exposed implant surfaces. Following a 5-week healing period, the contaminated parts of each implant were treated using three different cleaning techniques: (1) swabbing with supersaturated citric acid for 30 s on a cotton pellet followed by rinsing with physiological saline, (2) cleansing with a toothbrush and physiological saline only for 1 min, and (3) swabbing with 10% hydrogen peroxide (H2O2) on a cotton pellet for 1 min followed by rinsing with physiological saline. The treated implants and one previously unused implant (control) were then placed into freshly prepared tapped sites to the full implant length on the contralateral sides of the mandibles. Following 11 weeks of healing, biopsies were obtained and ground sections prepared for histomorphometric analysis. All treatment modalities were associated with direct bone to implant contact on the portion of implant surface previously exposed to the oral environment. In conclusion, The results demonstrate that osseointegration can occur to surfaces that were plaque contaminated and cleaned by different methods.