高扭矩植入种植体的近期疗效的对比研究

目的:对比高扭矩和常规扭矩植入的种植体在负重前骨吸收(MBR)水平和近期累积存留率的差异,探讨高扭矩植入种植体的可行性及并发症的预防.方法:以35例后牙区牙列缺损,接受种植修复的患者为研究对象,共有55枚Bio-Med 3i(R)Osseotite Tapered Certain种植体被纳入研究.种植体按植入扭矩值(ITV)分入A、B组,A组15枚种植体,ITV≤50N.cm,B组40枚种植体,50N.cm≤ITV≤90N.cm.采用埋置术式完成手术,术后即刻平行投照根尖片确定种植体周骨水平的基线,术后3～5个月复查时,再次投照种植体的根尖片,对比骨水平变化,得到负重前种植体MBR数据.结果:种植体植入术后3～5个月,A、B组间MBR值无统计学差异,全部种植体于二期术后一个月内完成固定烤瓷修复,平均随访11个月,观察期内种植体存留率100％.结论:观察期内高扭矩植入种植体不会引起种植体周骨吸收加重,近期疗效满意,值得进一步观察其远期疗效.     

后牙区骨密度对种植体骨结合稳定性的影响

目的应用锥束CT三维重建影像技术对后牙种植区骨密度进行定量测量,同时结合OS—STEL种植体稳定系数（ISQ）,分析表示骨密度的豪森菲尔德单位（HU）值及种植体稳定系数（ISQ）值对植入种植体稳定性的影响。方法对32名（男14人,女18人）后牙种植修复患者的49枚种植体进行术前测量种受植部位HU值,记录植入最大扭矩（Ncm）,在种植初期及5个月后进行共振频率分析（RFA）。结果49枚后牙区种植体全部存留;植入区HU值：477．76±129．88;植入时最大扭矩：35．82±10．275;初期ISQ：77．55±6．84;骨结合后ISQ：78．78±6．25。植人最大扭矩与初期ISQ（P=0．851）、植入区HU值与初期ISQ（P=0．721）未检出相关性,而植入区HU值与骨结合后ISQ值则有显著相关性（P〈0．01）。结论骨密度与种植体骨结合后稳定性密切相关,骨密度HU值越高,预后的种植体稳定性越高。     

聚四氟乙烯膜在即时植入的种植体与骨结合过程中的作用

通过Ｘ线照片，光镜、电镜观察，对聚四氟乙烯膜在即时植入的种植体与骨界面结合中的作用进行了探讨，结果表明膜能促进即时植入的种植体周围骨生长，缩短种植周期，值得临床推广应用。     

种植体骨结合稳定性测量及相关因素分析

目的:测量种植体骨结合稳定系数(ISQ),分析影响稳定性的相关因素。方法:对39名种植术后3~6个月后要进行修复的患者(男25,女14),102枚ITI种植体骨结合稳定性进行共振频率(RFA)测量。结果:ITI种植体骨结合ISQ为:76.29±5.25;ITI种植体稳定性主要受种植体骨质影响,密质骨(I、II)种植体稳定性(78.73±3.5)要高于松质骨(III、IV)的稳定性(74.27±5.63)(P<0.05);上颌与下颌的种植体稳定性差异不明显(P>0.05),上颌后牙区稳定性(77.57)要高于前牙区(73.65,P<0.05),下颌前后牙区无明显差别(P>0.05);不同长度不同直径种植体之间稳定性无明显差异(P>0.05)。结论:种植体稳定性与种植体周围骨质关系密切,种植体ISQ可以协助判断上部结构的修复时机,缩短种植修复的周期。     

口腔种植体骨性结合界面的研究进展

<正>Brnemark提出的骨结合理论无疑是种植义齿发展历程中的一座里程碑,它为牙种植的发展和临床应用提供了可靠依据,骨结合状况也成为预测种植义齿成功与否的先决条件[1]。     

螺距和外形对纯钛螺纹种植体初期稳定性的影响

目的:测量钛种植体植入扭矩(ITV)和稳定系数(ISQ),分析不同螺距和外形对种植体初期稳定性的影响.方法:将螺距分别为0.8 mm、1.2 mm、1.6 mm的柱状和两种锥形的机械表面钛种植体各12个植入新鲜的猪椎骨中,测量植入时扭矩和植入后种植体的稳定系数.结果:0.8 mm螺距种植体的植入扭矩(40.66±2.46)大于1.2 mm(38.33±2.60)和1.6 mm(38.05±2.83)者(p＜0.05),其稳定系数(74.38±3.61)也大于1.2 mm(71.91±4.33)和1.6 mm(71.44±3.78)者(P＜0.05);柱状、Taper I型和Taper Ⅱ型种植体的植入扭矩(分别为38.90±2.88、38.95、±2.68和39.20±3.08)未见明显差异(p＞0.05),柱状种植体的稳定系数(73.91±4.70)大于两种锥形种植体(71.90±3.90和71.9l±3.33),(p＜0.05);种植体的螺距和外形对其初期稳定性的影响无交互作用.结论:0.8 mm螺距种植体的初期稳定性优于1.2mm和1.6 mm者,柱状种植体的初期稳定性优于锥形种植体.     

生骨片对后牙区种植体骨结合的影响

目的 通过共振频率分析仪测量种植体的稳定系数（ISQ）,以明确生骨片对后牙区种植体骨结合状况的影响。方法 选取48例患者共101颗DENTIUM种植体作为研究对象,其中对照组24例患者（50颗种植体）按种植术后常规处理;余24例患者（51颗种植体）作为处理组,在种植术后常规处理的基础上加服生骨片。于种植术后即刻,术后4、8、12周利用共振频率分析仪测量ISQ值,将2组患者所测得的ISQ值进行比较。结果 处理组上、下颌骨种植体于术后即刻、术后12周所测得的ISQ值与对照组相比,差异无统计学意义（P>0.05）;术后4、8周所测得的ISQ值优于对照组,差异有统计学意义（P<0.05）。处理组和对照组下颌骨种植体于术后即刻,术后4、8和12周所测得的ISQ值优于上颌骨种植体,差异均具有统计学意义（P<0.05）。结论 种植术后早期服用生骨片,有助于加快种植体骨结合,提高术后4、8周种植体的ISQ值,进而降低种植体-骨关键愈合阶段的脱落风险,保证种植术的成功率,提供临床修复的时机。     

神经生长因子对口腔种植体早期骨结合影响的实验研究

目的 观察外源性神经生长因子(nerve growth factor,NGF)对口腔种植体骨愈合的影响,以期缩短口腔种植体骨愈合时间.方法 在12只新西兰大白兔下颌骨双侧各植入种植体1枚,右侧为实验组:种植体边缘骨膜下注射1.0μgNGF;左侧为对照组:同样部位注射相同剂量的生理盐水.注射1次/d,连续7 d.术后2、4、8周分别处死动物各4只,获取下颌骨,制作种植体骨磨片甲苯胺蓝染色标本,行大体、放射学和组织学观察以及骨计量学分析.结果 术后2、4周各组下颌骨种植体周围新生骨密度低于正常骨组织,种植体骨结合率对照组2周(26.67±3.88)%、4周(52.59±5.07)%;实验组2周(42.24±6.67)%、4周(72.25±6.30)%;术后8周两组骨密度与正常骨组织相近,实验组新生骨小梁出现哈弗系统,种植体骨结合率两组相比,差异无统计学意义.结论 口腔种植术后早期加入外源性NGF能够加速种植体周围骨小梁的形成和成熟,增加骨结合面积,提高种植体骨结合率,缩短口腔种植体骨愈合时间.     

实验性骨质疏松症对种植体周围骨量及骨结合的影响

目的 研究骨质疏松症对种植体周围骨量及骨结合的影响。方法 于３２周龄Ｗｉｓｔａｒ雌性大白鼠胫骨骨骺端植入羟基磷灰石（ＨＡ）种植体,术后５６ｄ实验组行卵巢摘除术,对照组行假手术。该术后２８、８４、１６８ｄ分别处死动物取胫骨、制作研磨切片标本,应用骨形态测量学技术探讨种植体周围单位骨量及与新生骨接触面积率的动态变化。结果 卵巢摘除术后２８ｄ,实验组单位骨量与对照组比较,差异有显著性;骨皮质部骨与种植体     

牙种植体表面结构对骨结合的影响

<正> Brnemark 提出的骨结合理论是种植义齿发展历程中的一个重要里程碑。经多年研究,Albrektsson等认为有以下6项重要因素影响骨结合:种植体材料、种植设计、表面条件、骨的状态、外科技术和负载条件。其中,种植体与种植区骨界面的相互影响一直是人们研究的热点。种植体表面微结构与达到良好骨结合有着密切关系,但具体的机制至今尚不十分     

A numerical approach to resonance frequency analysis for the investigation of oral implant osseointegration

Experimental devices based on vibration testing are employed as non-destructive procedures for evaluating implants osseointegration. Their behaviour was evaluated considering the outcome of numerical analysis. The purpose was to use the finite element method for assessing the ability of frequency analysis in detecting the degree of oral implant osseointegration. A three-dimensional model of a mandible was obtained from tomographic survey. A single implant was considered in canine region. Two configurations were analysed, with and without a mass linked to the implant as a cantilever, reproducing experimental devices. Simulation consisted of analysing the response to impulse forces for different osseointegration levels, thus evaluating the biomechanical efficiency of the implant-bone compound. A good correlation between frequency response and osseointegration level was obtained. This was carried out by providing an impulse excitation of the implant that resulted in a vibration pattern. Within the limit of finite element analysis, the outcomes showed that numerical investigation provides understanding the behaviour of testing devices based on frequency measurements, confirming the potential of vibrations technique as non-invasive analysis for osseointegration process.     

Clinical study on the insertion torque and wireless resonance frequency analysis in the assessment of torque capacity and stability of self-tapping dental implants

Summary  Resonance frequency (RF) analysis is a non-invasive, objective and sensitive technique developed for implantology where it measures the stability of the implant in osteotomy site. Although many studies were performed by the previous electronic version of RF analyzer, a very limited number of studies were carried out with the new magnetic wireless version. The aim of the study was to evaluate the relation between insertion torques, primary and secondary stability of self-tapping tapered implant systems. Thirteen subjects were treated with 42 endosseous implants using two-stage surgical procedure. The maximal insertion torque values were recorded prior to RF analysis during surgery. Six months after surgery, the secondary stability values were measured by the RF analysis. The average maximal insertion torque and primary and secondary magnetic RF values were 33 ± 11 N cm and 66 ± 12 ISQ and 71·9 ± 6 ISQ for 42 implants respectively. The correlation between insertion torque and RF values were indicated to be statistically significant ( P  < 0·01). Significantly higher maximal insertion torque, and primary and secondary magnetic RF values were achieved in mandibular sites compared with maxillary areas ( P  < 0·01). No significant differences were measured for all parameters when both systems were compared with each other ( P  > 0·05). There was a strong correlation between the insertion torque, primary and secondary magnetic RF values of self-tapping tapered endosseous implant used. Further studies are needed to understand the impact of the wireless magnetic RF analysis technique in clinics.     

Assessment of correlation between computerized tomography values of the bone, and maximum torque and resonance frequency values at dental implant placement

summary The aim of this study was to determine the bone density in the designated implant sites using computerized tomography (CT), the fastening torque values of dental implants, and the implant stability values using resonance frequency analysis. Further aim was to evaluate a possible correlation between bone density, fastening torque and implant stability. Eighty‐five patients were treated with 158 Brånemark System implants. CT machine was used for preoperative evaluation of the jawbone for each patient, and bone densities were recorded in Hounsfield units (HU). The fastening torque values of all implants were recorded with the OsseoCare equipment. Implant stability measurements were performed with the Osstell machine. The average bone density and fastening torque values were 751·4 ± 256 HU and 39·7 ± 7 Ncm for 158 implants. The average primary implant stability was 73·2 ± 6 ISQ for seventy implants. Strong correlations were observed between the bone density, fastening torque and implant stability values of Brånemark System TiUnite MKIII implants at implant placement (P < 0·001). These results strengthen the hypothesis that it may be possible to predict and quantify initial implant stability and bone quality from pre‐surgical CT diagnosis.     

Influence of defect depth on resonance frequency analysis and insertion torque values for implants placed in fresh extraction sockets: a human cadaver study

Background: Clinical studies show promising outcomes with implants inserted at the time of extraction. However, this often results in an initial bone defect at the marginal region which preferably should heal for an optimal function. Therefore, monitoring of these implants is vital.
Purposes: The aims of this study were to determine the initial stability of implants placed into fresh extraction sockets, and to explore the correlations between the peri-implant bone levels and implant stability parameters.
Materials and Methods: Six human cadaver mandibles including all natural teeth were selected for this study. All natural teeth were gently extracted, and 84 implants were immediately placed into fresh extraction sockets with five different implant depths. The maximum insertion torque values were recorded, and primary implant stability measurements were performed by means of resonance frequency analysis (RFA). The vertical distance between implant/abutment junction and the first bone–implant contact was recorded using a periodontal probe.
Results: It was found that the insertion torque and RFA were 28.9 ± 7 Ncm and 65.6 ± 9 implant stability quotient (ISQ), respectively, for 420 measurements from all 84 implants. Statistically significant correlation was found between insertion torque and ISQ values ( r  = 0.86; p  < .001) for all implants. Both insertion torque and ISQ values dramatically decreased when the amount of peri-implant vertical bone defect increased.
Conclusion: The results of this study demonstrated a linear relationship between peri-implant vertical bone defect depth and RFA value. It is proposed that the RFA method is sensitive to detect changes of the marginal bone level and may be used to monitor healing of peri-implant bone defects.     

The effect of implant design on insertion torque and immediate micromotion

Objectives: To evaluate the effect of insertion torque on micromotion to a lateral force in three different implant designs. Material and methods: Thirty‐six implants with identical thread design, but different cutting groove design were divided in three groups: (1) non‐fluted (no cutting groove, solid screw‐form); (2) fluted (90° cut at the apex, tap design); and (3) Blossom^? (Patent pending) (non‐fluted with engineered trimmed thread design). The implants were screwed into polyurethane foam blocks and the insertion torque was recorded after each turn of 90° by a digital torque gauge. Controlled lateral loads of 10 N followed by increments of 5 up to 100 N were sequentially applied by a digital force gauge on a titanium abutment. Statistical comparison was performed with two‐way mixed model ANOVA that evaluated implant design group, linear effects of turns and displacement loads, and their interaction. Results: While insertion torque increased as a function of number of turns for each design, the slope and final values increased (P<0.001) progressively from the Blossom^? to the fluted to the non‐fluted design (M±standard deviation [SD]=64.1±26.8, 139.4±17.2, and 205.23±24.3 Ncm, respectively). While a linear relationship between horizontal displacement and lateral force was observed for each design, the slope and maximal displacement increased (P<0.001) progressively from the Blossom^? to the fluted to the non‐fluted design (M±SD=530±57.7, 585.9±82.4, and 782.33±269.4 μm, respectively). There was negligible to moderate levels of association between insertion torque and lateral displacement in the Blossom^?, fluted and non‐fluted design groups, respectively. Conclusion: Insertion torque was reduced in implant macrodesigns that incorporated cutting edges, and lesser insertion torque was generally associated with decreased micromovement. However, insertion torque and micromotion were unrelated within implant designs, particularly for those designs showing the least insertion torque. To cite this article:
Freitas AC Jr, Bonfante EA, Giro G, Janal MN, Coelho PG. The effect of implant design on insertion torque and immediate micromotion.
Clin. Oral Impl. Res. 23 , 2012; 113–118.
doi: 10.1111/j.1600‐0501.2010.02142.x     

Predicting osseointegration by means of implant primary stability

The purpose of the present clinical study was (1) to evaluate the Osstell as a diagnostic tool capable of differentiating between stable and mobile ITI implants, (2) to evaluate a cut-off threshold implant stability quotient (ISQ) value obtained at implant placement (ISQitv) that might be predictive of osseointegration, (3) to compare the predictive ISQitv of immediately loaded (IL) implants and implants loaded after 3 months (DL). Two patient groups were enrolled, 18 patients received 63 IL implants and 18 patients were treated with 43 DL implants. The ISQ was recorded at implant placement, after 1, 2, 4, 6, 8, 10 and 12 weeks. All implants passed the 1-year loading control. Two implants failed, one DL implant with ISQ at placement (ISQi) of 48 and one IL implant with ISQi of 53. The resonance-frequency analysis (RFA) method was not a reliable diagnostic tool to identify mobile implants. However, implant stability could be reliably determined for implants displaying an ISQ> or =47. After 1 year of loading, all DL implants with an ISQi> or =49 and all IL implants with an ISQi> or =54 achieved and maintained osseointegration. By the end of 3 months, implants with ISQi<60 had an increase of stability. Implants with ISQi 60-69 had their stability decrease during 8 weeks before returning to their initial values. Implants with ISQ>69 had their stability decrease during the first 4 weeks before remaining stable. Although preliminary, these data might orient the practitioner to choose among various loading protocols and to selectively monitor implants during the healing phase.     

含镁羟基磷灰石涂层对卵巢摘除大鼠种植体骨整合的影响

目的探讨羟基磷灰石涂层(hydroxyapatite,HA)中加入镁元素对植入卵巢摘除(ovariectomized,OVX)大鼠体内种植体的稳固性的影响。方法采用溶胶-凝胶法制备种植体表面涂层,对照组为传统的羟基磷灰石涂层,实验组为用镁元素替代羟基磷灰石中10%钙元素的涂层(magnesium-containing hydroxyapatite,MgHA)。另取18只OVX大鼠,随机分为2组,一组在双侧股骨远心端各植入1枚HA涂层种植体,另一组则植入MgHA涂层种植体。12周后,连同周围骨组织取出种植体进行组织形态计量分析、Micro-CT评价、生物力学测试。结果 MgHA组骨-种植体接触率、骨面积比率分别为(52.57±4.73)%、(36.76±3.31)%,HA组为(34.06±5.20)%、(27.26±2.92)%;MgHA组的最大推出强度、界面剪切强度为(63.98±4.08)N,(2.63±0.25)N/mm2,HA组为(41.44±7.07)N,(2.22±0.33)N/mm2,P<0.01。此外,MgHA组骨体积分数(24.5±6.1)%、骨小梁厚度(80.6±11.9)μm、骨小梁数量(5.8±0.5)mm-1、骨小梁分离度(194.7±38.2)μm、连接密度(51.9±5.6)mm-3、骨整合率(58.6±6.2)%;而HA组为(16.6±4.3)%、(68.4±10.3)μm、(5.2±0.6)mm-1、(220.8±30.6)μm、(44.1±4.5)mm-3、(45.1±3.8)%,除骨小梁分离度无统计学差异外,其余P<0.05。结论镁元素能改善骨质疏松骨中种植体的生物性能。     

全身应用催产素对骨质疏松大鼠种植体骨结合的影响

目的 探讨骨质疏松大鼠全身应用催产素对种植体骨结合的影响。方法 20只大鼠平均分成对照组和实验组,接受双侧卵巢切除术以建立骨质疏松模型。12周后,在每只大鼠的双侧股骨远中干骺端各植入1枚种植体,同时接受催产素全身用药,实验组皮下注射催产素（每天1 mg•kg-1）,对照组注射生理盐水。用药4周后,观察8周,手术取出大鼠胫骨和带有种植体的股骨,采用显微CT和组织学染色观察大鼠胫骨的骨质疏松情况,用显微CT、组织学观察和推出试验评价骨结合效果。结果 实验组与对照组相比,胫骨样本的骨小梁增多、密集,交织成网状,骨质疏松模型成功建立。实验组种植体周围的相对骨体积分数为0.35%±0.06%,骨结合率为67.25%±9.06%,最大推出力为（70.32±10.91） N,对照组的相对骨体积分数、骨结合率和最大推出力分别为0.11%±0.02%、43.25%±7.01%、（21.65±4.36） N,实验组较对照组均明显增加（P<0.05）。结论 全身应用催产素可拮抗骨质疏松的负面影响,促进种植体愈合,对纯钛种植体的骨结合具有正向影响。