【作者】 单丽华；

【导师】 董福生；

【作者基本信息】 河北医科大学 ， 外科学， 2010， 博士

【摘要】 错牙合畸形影响颅颌面的发育、口腔健康、口腔功能及面容,甚至影响精神和心理健康。据报道,错牙合畸形在我国的发病率高达72.92%。随着生活水平及口腔健康认识的提高,要求正畸治疗的患者越来越多。正畸治疗过程中,支抗控制是正畸治疗的基础,支抗不足是目前限制正畸学发展的重要因素。目前临床常用的支抗控制方法包括口内及口外装置,然而,所有的口内装置都有一定程度的支抗丧失,口外支抗如没有患者的良好配合则不能提供可靠的支抗。近年来出现的微型种植体由于尺寸小、植入部位灵活、手术简单、可以即刻载荷等优点,越来越多地用于正畸治疗,尤其对疑难病例的治疗显示出独特的优越性,受到国内外学者的广泛关注。然而微型种植体脱落情况时常发生,据报道微型种植体的成功率为83-89%。如何提高微型种植体的稳定性是目前的研究热点。种植体脱落大多发生在正畸加力前和加力过程中,多由于种植体植入手术不当及种植体-骨界面不合适的应力分布造成。种植体的稳定性受多方面因素的影响,种植体植入后必须满足初期稳定性及随后载荷给予的应力和应变的要求。良好的微环境有利于形成种植体-骨愈合及承受载荷,其中种植体的选择、植入手术、初期稳定性、载荷方向及愈合时间等是影响微型种植体稳定的重要因素。明确稳定性的影响因素及规范操作系统的研究对推广微型种植体支抗的应用意义重大。本研究通过建立不同长度不同载荷骨量、相同长度不同植入方向、相同长度不同载荷方向的下颌骨-微型种植体三维有限元模型,分析正畸载荷对骨组织内的应力分布及位移的影响,为临床合理选择、使用微型种植体,减少骨界面应力集中,提供理论依据；通过建立不同植入扭力及不同愈合期载荷的动物模型,探讨微型种植体不同植入扭力对种植体-骨界面愈合的作用,评价种植体-骨界面不同愈合期后载荷的生物力学及组织学特性,为临床选择合适的植入扭力并根据初期稳定性选择载荷时机提供参考；通过微型种植体不同愈合时间载荷的临床试验,探讨其稳定性的相关影响因素。本实验希望能为今后微型种植体的临床研究和应用奠定坚实的基础,提供可靠的理论依据和实验室数据。1.利用颌骨CT扫描图象,应用计算机辅助设计和ANSYS10.0软件建立下颌骨三维有限元模型。2.建立直径为1.6mm,长度分别为6mm、8mm、10mm、12mm四种长度种植体模型。3.装配实体微型种植体-下颌骨三维有限元模型3.1微型种植体植入位置：下颌第一磨牙与第二前磨牙牙根之间距离牙槽嵴顶4mm处。3.2装配6mm,8mm,10mm,12mm四种长度种植体垂直骨面植入模型。3.3装配8mm种植体与骨表面成90°垂直植入、牙合向30°植入(种植体向牙合平面方向倾斜60°,与骨表面成30°)、牙合向60°植入(种植体向牙合平面方向倾斜30°,与骨表面成60°)、近中向30°植入(种植体向近中方向倾斜60°,与骨表面成30°)、近中向60°植入(种植体向近中方向倾斜30°,与骨表面呈60°)的五种植入角度模型。1.选择6mm、8mm、10mm、12mm四种长度种植体垂直植入模型。2.分别在种植体顶端施加1.96N的载荷。3.载荷方向：通过种植体载荷点做一与牙合平面平行的直线,通过此直线做一与地平面垂直的平面,在此平面上分别给以水平向前及前上斜向45°方向的载荷。4.对各模型的不同载荷条件计算种植体周围骨界面Von-Mises应力峰值及位移峰值。1.选择90°垂直植入、胎向30°植入、牙合向60°植入、近中向30°植入、近中向60°植入的五种植入角度模型。2.在种植体顶端施加1.96N水平向前的载荷。3.计算种植体周围骨界面Von-Mises应力峰值。1.选择牙合向30°植入、近中向30°植入两种模型。2.在种植体顶端施加1.96N大小的载荷。3.载荷方向3.1牙合向30°植入：通过种植体载荷点做一与殆平面平行的直线,通过此直线做一与地平面垂直的平面,在此平面上分别给以水平向前、前上45°方向、垂直向上方向的载荷。3.2近中向30°植入：通过种植体载荷点做一与牙合平面平行的直线,通过此直线做一与地平面垂直的平面,在此平面上分别给以水平向前、水平向后、前上45°方向、后上45°方向、垂直向上方向的载荷。4.对各模型的不同载荷条件计算种植体周围骨界面Von-Mises应力峰值。1.动物与分组：年轻成年雄性Beagle狗4只,按照植入力分为14N±1Ncm扭力组及11±1Ncm扭力组。2.实验步骤与方法2.1将36颗直径1.5mm、长7mm的微型种植体分别种植在Beagle狗的下颌第2、3、4前磨牙及第一磨牙范围内两牙根之间,两组种植体随机分配在每只狗的左右侧。2.2每组分别于植入后7天和28天取材、固定。2.3制作种植体及周围骨组织不脱矿的硬组织切片,用光学显微镜观察骨界面愈合情况,用图文分析软件测量、计算骨组织界面形态学指标。2.4用扫描电镜观察种植体-骨界面的结合情况。2.5结果采用方差分析法分析两组扭力值之间和不同时间后骨组织界面形态计量学指标之间差异。P<0.05时认为具有统计学意义。1.动物与分组：8只年轻成年雄性Beagle狗。实验组：种植体分别于植入后即刻、愈合1周、愈合3周及愈合8周后行初载荷,载荷持续10周后取材。对照组：种植体不载荷,分别于植入后1周、3周、8周、10周后取材。2.1将64枚种植体植入在Beagle狗的下颌骨内,种植体植入位置同实验五。2.2植入扭力选择12±1Ncm。植入种植体时测量植入扭力。2.3实验组种植体分别在植入后即刻、植入后1,3,8周后给以100g的载荷,对照组不载荷。2.4按照实验设计时间旋出种植体,测量两组种植体旋出扭力峰值。2.5扫描电镜观察旋出种植体表面情况。2.6用方差分析法分析不同愈合时间后载荷及不载荷旋出扭力峰值间的差异。P<0.05时认为具有统计学意义。1病例选择：2005年12月至2009年12月选用正畸门诊需强支抗的错殆畸形患者植入种植体,进行早期载荷或延期载荷。共46例,男11,女35,平均年龄17.5岁。2种植体植入位置：按照错牙合奇形治疗的需要及局部解剖情况,将微型种植体植入牙弓前部及后部的唇、颊侧或腭侧牙槽嵴。3分组：①早期载荷：植入后4周载荷,载荷力为75-100g,12周后150-200g；②延迟载荷：种植体植入后12周开始载荷,载荷力为150-200g。4记录宿主基本情况、植入位置、植入后疼痛否、口腔卫生情况、愈合期、种植体脱落情况等。5计算种植体脱落率,卡方检验分析种植体脱落的相关临床因素。P<0.05时具有统计学意义。1.成功建立6mm、8mm、10mm、12mm四种长度微型种植体垂直植入的下颌骨-种植体模型。2.成功建立8mm长度种植体的90°垂直植入、牙合向30°植入、牙合向60°植入、近中向30度植入、近中向60°植入五种植入角度的下颌骨-种植体模型。3.建立的有限元模型的几何相似性、生物力学相似性及临床适应性均达到实验要求。1.不同加载条件下应力集中部位均出现在种植体颈部骨界面内。2.不同长度种植体相同方向载荷时骨界面应力峰值及位移峰值变化不大。3.6mm、8mm、10mm、12mm长度种植体水平前向牵拉的应力峰值分别为3.765 Mpa、3.726 Mpa、3.627Mpa、3.5 Mpa,位移峰值范围为1.266-1.288μm。前上斜向牵拉的应力峰值分别为4.51 Mpa、4.477Mpa、4.392 Mpa、4.075 Mpa,位移峰值范围为1.668-1.694μm。1.不同载荷骨量明显影响骨界面应力分布：水平前向牵拉的应力峰值及位移峰值均低于前上斜向牵拉。2.不同加载条件下应力集中部位均出现在种植体颈部骨界面内。3.殆向30度植入、牙合向60度植入、90度植入、近中向60度植入、近中向30度植入的Von-Mises应力峰值分别为3.386 MPa、3.536 MPa、3.726 MPa、1.385 MPa、0.436 MPa。4.骨界面应力均匀分布依次为：近中向30°植入、近中60°植入、牙合向30°植入、牙合向60°植入、90°植入。1.不同加载条件下应力集中部位均出现在种植体颈部。2.种植体牙合向30度植入：水平前向载荷、前上方向载荷、垂直向上载荷的应力峰值分别为3.396 MPa,1.143 MPa,1.096 MPa。骨界面应力均匀分布的载荷依次为：垂直向上载荷、前上方向载荷、水平前向载荷。3.种植体近中向30度植入：水平前向载荷、水平后向载荷、前上方向载荷、后上方向载荷、垂直向上载荷的应力峰值分别为0.436 MPa,0.452MPa,1.936 MPa,1.817 MPa,2.618 MPa。骨界面应力均匀分布的载荷依次为：水平前向载荷、水平后向载荷、后上方向载荷、前上方向载荷、垂直向上载荷。在4只狗的下颌共植入36颗种植体,其中2颗种植体脱落。11±1Ncm扭力植入组成功率100%,14±1Ncm扭力植入组成功率88.9%,两者差别无统计学意义(P>0.05),总成功率为94.4%。14±1Ncm扭力植入种植体植入后7天,可见种植体颈部或根尖部皮质骨有染色的弥散性损伤及染色性交叉岔折损伤,植入后28天,仍可见少量重染损伤区,微破裂明显减少。而11±1Ncm扭力植入种植体植入后7天,种植体颈部皮质骨可见少量分散的微破裂,而植入后28天,微破裂消失。11±1Ncm扭力植入组与14±1Ncm扭力植入组7天和28天的种植体-骨接触率无明显区别(P>0.05)。但11±1Ncm扭力组28天时50μm和150μm范围内种植体-骨界面密度(分别为53.15%,51.53%)明显高于14±1Ncm扭力组(分别为32.56%,34.55%),P<0.05。共植入64颗种植体,其中有3颗脱落。载荷组成功率96.9%,非载荷组成功率90.6%,差异无统计学意义(P>0.05),总成功率为93.8%。微型种植体植入后,载荷及非载荷的界面骨组织均随着时间的延长进行愈合。适量正畸载荷可以促进骨组织的愈合。微型种植体植入后即刻载荷及愈合1周、愈合8周后载荷的界面骨组织愈合良好,但植入后3周载荷的愈合较差。非载荷种植体不同愈合时间的旋出扭力值无明显区别,平均为2.42±0.29Ncm。载荷组种植体在即刻载荷及愈合1周、3周及8周后载荷的旋出扭力分别为4.10±0.39Ncm、4.25±0.70Ncm、2.42±0.44Ncm、4.42±0.38Ncm,愈合3周后载荷的旋出扭力值与非载荷种植体旋出扭力值相似(P>0.05),明显低于其它愈合时间载荷的旋出扭力值,P<0.05。共植入微型种植体109枚。其中有10颗种植体松动、脱落,6颗发生在载荷前,1颗在早期载荷1个月内,3颗发生在延期载荷期间。种植体总成功率为90.83%。脱落较多发生在上颌腭侧、下颌前部及后部颊侧。早期载荷与延期载荷成功率无明显区别。种植体植入后距离牙根较近及种植体周围炎容易导致种植体脱落。1微型种植体植入方向及角度影响种植体骨界面应力分布。应根据载荷方式选择种植体植入方向,尽量使植入方向与载荷方向一致,并尽量减少种植体与骨面间的植入角度。2微型种植体长度在6-10mm范围变化时,正畸载荷对种植体-骨界面应力分布影响不大。在此范围内临床上不用刻意选择长微型种植体。3载荷方向影响种植体-骨界面应力分布。临床微型种植体载荷时,尽量沿着种植体植入方向的种植体长轴加载(与种植体植入方向一致或相反),载荷方向与种植体植入方向的种植体长轴垂直时容易造成骨界面应力集中。4种植体初期稳定性是形成骨整合的基础。适度的植入扭力有利于建立一个良好的种植体-骨愈合微环境。种植体植入后,应将种植体与周围骨组织间压力控制在一定的范围内,保证骨组织的血液供应。合适的植入扭力(11Ncm)骨界面损伤小、愈合快,有利于种植体稳定性。过强的植入扭力(14Ncm)可以造成种植体周围应力集中区骨质严重微损伤,且骨愈合过程减慢。临床植入微型种植体时,适度的植入力较好,而不是越大越好。5微型种植体植入后,早期适度的机械刺激有助于种植体-骨愈合。6微型种植体植入到骨整合完成前(3周左右)出现种植体稳定性危险期。在种植体植入后,可以进行即刻或愈合1周后正畸载荷,否则应选择愈合后载荷,但应避免愈合危险期加载。7初期稳定性是微型种植体选择早期载荷的重要条件,对初期稳定性好的微型种植体进行即刻载荷或早期载荷不影响其骨整合的形成。8为了减少种植体脱落率,应控制种植体周围炎症,尤其是上颌腭侧及下颌后部颊侧植入种植体时。更多还原

【Abstract】 Objective:Malocclusion affects craniofacial development, oral health and founction, facial esthetics, psysical and psychological health seriously. In China, the prevalence of malocclusion is reported by 72.92%. The number of patients requiring orthodontics thearoy has undergone a marked increase in recent decades with the standard of living and awareness of oral health. Anchorage control is a fundamental aspect of orthodontic biomechanics. Poor anchorage control is one important limiting factor for Orthodontics development. There have been many attempts to divise suitable anchorage methods, including introral and extraoral appliances. All intraoral appliances, however show some loss of anchorage. Extraoral appliances do not privide reliable anchorage without patient’s comppliance. Especially, mini-implants have increasingly been used in cesent years for orthodontic anchorage because of their small size, flexible insertion site, ease placement, can immediately loading, and accepeted attention by scholar. However, mini-implants still fail frequently. Miyawaki and Cheng et al repoted that the success rates for mini-implants were 83-89% How to improve implant stability is the research focus.The fell off implants happen mostly before orthodontics loading and during the process of loading. Failure of oral implants may often be attributed to inadequate operation and biomechanical coupling between implant and bone. The stability of implant was influenced by many factors. Implants must satisfy requirements of primary satility, and later they must withstand the srtesses and strains to which they subjected. Good micro-environment is conducive to the formation of implant-bone healing and to withstand load. The choice of implant, implant surgery, initial stability, load direction, and healing time are the important factors on stability of mini-implants. Therefore, the studies that make clear the influencing factors on the stability and standardize the operating system are important to popularize and use mini-implant.This research established some models of mandible with mini-implant including different insertion angles, mini-implant lengths and loading directions. Analyzing the stress distribution and displacement in bone influenced by orthodontics loading. The purpose was to offer a theoretical basis to rational choice and use mini-implant in clinical, reduce stress concentration in bone interface. To Study the effection of different insertion torque on bone healing by means of establishing animal models with different insertion torque and healing periods under loading. This study is to observe the biomechanical and histologica properties of peri-implant bone under different heailing period. It can also provide a reference for chosing rational insertion torque and loading period according to initial stability. To explore the relevant factors of stability through clinical loading tests under different healing period. The results would provide experimental data and theory for the future clinical studies and pro-clinic applies.1 Experiment one:Establishing the FEA models of the jaw with mini-implant1.1 Obtaining three dimensional radiographic data of the jaw by CT scan, the three-dimensional finite element analysis mandible model was established.1.2 The four kinds of mini-implant models were established. And the diameter was 1.6mm, the length were 6mm,8mm,10mm and 12mm respective.1.3 The insertion region of implant was in the between first molar and second premolar. Four lengths of 6,8,10,12mm of implant modles were inserted vertically into designed site of mandibular and 8mm length of implant was embbed vertically,30°tilted mesiolly,60°tilted mesiolly,30° tilted occlusally,60°tilted occlusally, respectively.Four lengths of 6,8,10,12mm of implant-mandible modles were chosen. A force of 1.96N was applied.mesioly and 45°tilted mesiol-vertically in modles. The stress distribution under every condition was recorded and analyzed.The chosen models were that the implants were inserted vertically,30°tilted mesiolly,60°tilted mesiolly,30°tilted occlusally,60°tilted occlusally, respectively. A load of 1.96N was applied mesiolly to the head of implant, caculated the maximum Von-Mises stress.The model with implant inserted 30°tilted mesiolly was loaded by a force of 1.96N mesiolly, mesiol-vertically, vertically, distal-vertically, distally, respectively. The model with implant inserted 30°tilted occlusally was loaded by a "force of 1.96N mesiolly, mesiol-vertically, vertically, respectively. The stress distribution under every condition was recorded and analyzed.5.1 Experimental design:The implants were equally divided into 14±1Ncm and 11±1Ncm insertion torque among 4 adult male Beagle dogs.5.2 Empirical procedure and method:Thirty-six mini-implants (1.5mm in diameter,7mm in length) were placed buccaly at the interradicular with second, third, forth premolars and first molar bilaterally of the mandibular of dogs.14±1Ncm insertion torque and 11±1Ncm insertion torque were made on two groups at the time of fixture placement. Bone tissue responses were evaluated by histological analysis at 7 days and 28 days after implant placement. Following an observation period of 7 and 28 days, the mini-implants and the surrounding bone were removed. Undecalcified serial sections were made and the degree of ossointeration studied. All measurements were statistically evaluated using independent t-ests to determine any difference in insertion torques and histomorphometric analysis, (bone-implant contact and bone area). A P value less than 0.05 was considered significant.6.1 Experimental design:8 twelve month-old male beagle dogs were divided into two groups. The test mini-implants remain in the low jaw for an additional 10 wks of force application (100 g) after 0,1,3 and 8 weeks of bone healing. Healing control (HC) implants were further divided into 4 groups (1,3,8 and 10 weeks). It is important to note that the HC implants to termination of the experiment were placed in the jaw for 1,3,8, or 10 wks prior so that bone could be assessed at the initiation of loading.6.2 Empirical procedure and method:Sixty-four mini-implants were placed in low jaw among 8 twelve month-old male beagle dogs. The location and surgical procedure of this study were sismilar to which in study four. The insertion torques was 12±1Ncm. Recorded the insertion torques while the implants were embedded. The test mini-implants of force application (100 g) after different bone healing period according to disign. Maximum removal torque (MRT) testing was performed to evaluate the interfacial shere strength of each test groups. Surface analysis of removed implants were performed by SEM. MRT of two groups after different healing period were compared with the use of ANOVE. A P value less than 0.05 was considered significant。Forty-six patients who required skeletal anchorage for orthodontic therapy were included in a prosective study. A total of 109 mini-implants (1.5mm in diameter,7mm in length) were placed in 46 patients (11 males,35 females, and average age of 17.8 years old). A variety of orthodontic loading were applied after varied healing period including early and delayed loading. Possibe correlation between various clinical parameters and mini-implant failure and complications were evaluated by the chi-aquare or Fisher exact tests where appropriate. AP value less than 0.05 was considered significant.1 Experiment one:The three-dimentional FEA models of mandible and mini-implants were established:Four lengths of mini-implant models obtained were 6mm、8mm、10mm and 12mm. Five insertion angle models of mini-implant with 8 mm of length were established, embedding angle were vertical,30°tilted occlusally,60°tilted occlusally,3°tilted mesiolly,60°tilted mesiolly, respectively. The geometric, biomechanics similarity and clinical adaptability of modles established achieved the test requirements.2 Experiment two:Stress distribution on bone under different mini-implant lengths:The results showed that the peak stress occurred at the cervical bone margin adjacent to the implants on different loading conditions. The change of the length didn’t show much influence on the stress ditribution. When given load mesiolly, the maximum stress varied from 3.765Mpa to 3.5Mpa, the maximum displacement varied from 1.288μm tol.266μm. When load was applied 45 degree mesiol-vertically, the maximum stress varied from 4.51Mpa to 4.075 Mpa, maximum displacement varied from 1.694μm to 1.668μm.3 Experiment three:Stress distribution on bone adjacent to a mini-implant under different embeded direction:The results showed that the peak stress occurred at the cervical bone margin adjacent to the implants. When inserted with 30°ilted mesiolly, the peak stress is less than other models obviously and the stress distributions of 60°ilted mesiolly was more even secondly. When mini-implants inserted with angle of 90°nd 60°ilted occlusally, the stress concentration was more obvious and the peak stress was the highest.4 Experiment four:Stress distribution on bone under different loading directions of mini-implan:The rerults showed that when mini-implants inserted with angle of 30°tilted occlusally, stress distribution of loading vertically was evener than loading mesiol-vertically, loading mesiolly was the unevenest. When inserted with 30°tilted mesiolly, stress distributions of loading mesiolly and distally were more even, and the difference with them was little. The strees distribution of vertical loading was the unevenest.5.1Clinical observation when mini-implants inserted with 11±1Ncm and 14±1Ncm torque value:A total of 36 implants were placed in mandible of 4 beagle dogs,2 of them failed. The survival rates of implants with 11±1Ncm and 14±1Ncm torque value were 100%,88.9%, respectively. There were no significant differences between two groups. The total success rate was 94.4%.5.2Observation by light microscope when mini-implants inserted with 11±1Ncm and 14±1Ncm torque value:The histomorphologic analysis showed that diffuse staining and cross-hatch staining were discovered in cortical bone of implant neck or apex with 14±1Ncm torque after 7 day. The microdamage still exist after 28 day. In contrast, cross-hatch staining was discovered in cortical bone of implant neck with 11±1Ncm torque after 7 day, but disappeared after 28 day.5.3The histomorphometry analysis:The results showed that there were no significant differences for the BIC between 11±1Ncm group and 14±1Ncm group at 7 day and 28 day. But the BA within 50μm and 150μm for the 11±1Ncm group (53.15%,51.53%, respectivly) were great than 14±1Ncm group (32.56%,34.55%, respectivly) at 28 day.6.1 Clinical observation:A total of 64 implants were placed in mandible of 8 beagle dogs,3 of them failed. The success rates were 96.9% for loading mini-implants,90.6% for unloadings, and 93.8% for overall.6.2SEM observations:The results indicate that the mineral formation in the nanosized layer adjacent to the titanium surface of mini-implant increases over time for loading and unloading groups. The striking finding was the loading promotes the bone healing around implants, except healing of 3 wks.6.3Removeal torque value changes:There were no signifacant differences for removeal torque value of unloading implants, mean of 2.42±0.29Ncm. The mean removal torque values for the loading implants were 4.10±0.39Ncm at 0 week,4.25±0.70Ncm at 1 week,2.42±0.44Ncm at 3 weeks and 4.42±0.38 Ncm at 8 weeks. During the process of healing, the removal torque values of tested implants were significant highter than control implants except at 3 weeks.Implant mobility or complete exfoliation was found for ten implants among 109 mini-implants. Six of them failed before the appilication of orthodontic load, one implant was lost after loading of less than 1 month, and three were lost during delayed loading period. The overal mini-implants success rate was 90.83%. Mini-implants on the buccal and labial side of the mandible and palatal side of maxilla had a higher failure rate. There was no significant difference between early loading and delayed loading. Root contact during placement of mini-implants and inflammation increased significantly the possibility of implant failure.1 Insertion direction and angle of the mini-implant can affect the stress distribution of infacial bone. Embbeding direction of the implant shoud be accordance,with loadingdirection as much as possible, and decrease the angle between bone sueface to long axies of implant.2 The change of the length within 6mm-12mm didn’t show much influence on the stress distribution. There is no use to select longer mini-implants strictly. 3 Loading direction and angle of the implant can affect the stress distribution of infacial bone. Loading direction of implant should be accordance with or contrary to the insertion direction of implant for orthodontic anchorage. When loading derection was perpendicular with long axis of the implant, the interfacial bone will result in stress concentration.4 Primary stability is basis of osseointergation formation of mini-implants. Suitable insertion torque of mini-implant is in favor of good micro-environment of peri-implant bone healing. The strees between the implant and infacial bone should Control within certain limits to guarantee blood supply for bone. Appropriate insertion torque produce bone interface with little microdamage, and healing speedy. Heavy insertion torque can cause intense bone microdamage around interface of implant-bone by strong stress concentration, damnify the healing of the implant-bone interface. The mini-implants should be placed using an appropriate insertion torque, over-tighting should be avoided.5 Suitable mechanical stimulation contributed to healing of bone-implants after mini-implant was inserted.6 There are a stable dangerous period, after mini-implant was inserted and before the bone remodeling to complete. As a function of healing time, orthodontics loading immediately or 1 week,8 week after implant was inserted appear a positive effect on peri-implant bone remodeling and implant stability except at 3 weeks of healing period.7 Initial stability is an important condition for early loading of mini-implant. When implant inserted with good primary stability, early orthodontics loading is considered no impact to implant-bone healing.8 To reduce the failure rate, the inflammation around the implant body should be controled, particularly mini-implants were inserted on the buccal and labial side of the mandible and palatal side of maxilla.更多还原