愈合時間對Ⅲ類骨質(zhì)中微種植體穩(wěn)定性影響的三維有限元分析
發(fā)布時間：2019-07-02 10:07
【摘要】：目的：正畸治療過程中支抗的控制是影響治療效果的關(guān)鍵因素。微種植體支抗與腭桿、舌弓、口外弓等傳統(tǒng)支抗相比，憑借其操作簡便、創(chuàng)傷小、成本低以及療效可靠等優(yōu)點(diǎn)，成為近年來正畸領(lǐng)域的研究熱點(diǎn)并越來越多的應(yīng)用于臨床。 微種植體為正畸治療提供強(qiáng)支抗的前提是微種植體自身的穩(wěn)定性，而其穩(wěn)定性與頜骨質(zhì)量密切相關(guān)。頜骨質(zhì)量在人群中有很大的變異，臨床應(yīng)用中常發(fā)現(xiàn)有些青少年具有較薄的皮質(zhì)骨，植入種植體時初期穩(wěn)定性較差，延長愈合時間及調(diào)整載荷力值是否能提高種植體成功率很少有報道。 微種植體的固位形式主要有機(jī)械嵌合力和生物結(jié)合兩種方式。機(jī)械嵌合力主要是在種植體植入初期，還未形成骨結(jié)合的情況下，由微種植體與骨組織之間的摩擦力提供。生物結(jié)合又分為纖維結(jié)合（種植體與骨組織間存在一層非礦化的纖維結(jié)締組織）、骨結(jié)合（種植體與骨組織直接接觸，其間不存在骨以外的組織，達(dá)到種植體與骨組織在結(jié)構(gòu)和功能上的直接聯(lián)系）以及混合性結(jié)合。 研究表明，微種植體加載前的愈合時間會對其穩(wěn)定性產(chǎn)生一定影響，但最佳加載時間仍存在爭議。傳統(tǒng)觀點(diǎn)認(rèn)為，種植體植入后，應(yīng)保證一定的骨愈合過程再加載，以提高骨結(jié)合率，從而保證其穩(wěn)定性。而近年來一種新的觀點(diǎn)認(rèn)為，種植體植入早期固位良好者一定限度的微動有利于骨結(jié)合，這為微種植體即刻加載提供了依據(jù)。 研究種植體支抗的方法很多，近年來證明三維有限元是一種有效的力學(xué)分析方法。應(yīng)用三維有限元進(jìn)行分析可以更為精確的模擬實(shí)物內(nèi)部的結(jié)構(gòu)和組織學(xué)變化。因此三維有限元法現(xiàn)在廣泛的應(yīng)用于正畸領(lǐng)域中。 本實(shí)驗(yàn)擬采用三維有限元方法，建立Ⅲ類骨的模型及種植體支抗模型，通過加載前不同愈合時間微種植體-骨接觸面的不同，對模型進(jìn)行應(yīng)力分析，從而觀察及比較Ⅲ類骨不同愈合時間對微種植體穩(wěn)定性的影響，為指導(dǎo)臨床應(yīng)用提供理論依據(jù)，提高種植的成功率。 方法： 1實(shí)驗(yàn)設(shè)備 計(jì)算機(jī)：臺式，(Intel(R) Xeon(R) CPU E5-1650，3.20GHz:8G內(nèi)存，win7,64bit位操作系統(tǒng)) 軟件包：Catia V5，Hyperworks11.0，Abaqus6.10 2微種植體-頜骨模型的設(shè)定 2.1建立頜骨模型 依據(jù)一女性志愿者上頜骨左側(cè)第二前磨牙與第一磨牙之間種植體植入部位的頜骨CT縱斷面，建立頜骨模型。頜骨表面部分為皮質(zhì)骨，厚度為0.7mm，內(nèi)部為松質(zhì)骨。根據(jù)實(shí)際的尺寸，將斷面簡化成等腰梯形，斷面尺寸：上表面寬15mm，下表面寬13.5mm，，高7.5mm。然后用面拉伸成長20mm的六面體。 2.2建立微種植體模型 根據(jù)臨床常用正畸微種植體形態(tài)建立微種植體模型，數(shù)據(jù)如下：總長度12mm，骨內(nèi)段總長度8mm、直徑1.6mm、螺紋高度0.2mm、刃狀螺紋頂角60°、螺距0.6mm。 2.3裝配微型種植體-上頜骨實(shí)體模型 將頜骨及微種植體按照相應(yīng)位置進(jìn)行裝配得到微種植體-頜骨模型。在種植體頸部分別施加1N及2N的正畸力。設(shè)定以齦方為Y軸正向，以遠(yuǎn)中為X軸正向，以種植體長軸為Z軸。加載方向?yàn)槠叫杏赬-Y平面（垂直于種植體長軸）與Y軸平行方向相反（牙合方）的正畸力。 2.4實(shí)驗(yàn)分組設(shè)計(jì)： 2.4.1即刻加載組（Immediate Load，IL）： 采用庫侖摩擦模型模擬非骨結(jié)合狀態(tài)，摩擦系數(shù)μ=0.2。同時采用過盈配合的方法模擬種植體骨界面的初始應(yīng)力。 即刻加載1組（Immediate Loading1，IL1）：設(shè)定過盈量為0.03； 即刻加載2組（Immediate Loading2，IL2）：設(shè)定過盈量為0.05； 即刻加載3組（Immediate Loading3，IL3）：設(shè)定過盈量為0.1； 2.4.2早期加載組（Early Loading, EL）及延期加載組（Delay Loading，DL）： EL組和DL組分別模擬愈合３周后及愈合７周后加載的情況，以微種植體-骨結(jié)合率（bone-implant contact rate，BIC）定義兩組的微種植體-骨接觸面： EL組：BIC=34% DL組：BIC=44% 通過微種植體-骨界面不同比例的骨結(jié)合和非骨結(jié)合來模擬不同微種植體-骨結(jié)合率。骨結(jié)合與非骨結(jié)合區(qū)域間隔出現(xiàn)，并隨機(jī)分配。骨結(jié)合區(qū)域骨組織和種植體界面單元在載荷作用下相對位移為0，為固定接觸；非骨結(jié)合區(qū)域界面單元在外力作用下允許相對滑動，摩擦系數(shù)μ=0.2。 3材料 3.1材料屬性 假設(shè)種植體，皮質(zhì)骨和松質(zhì)骨均為連續(xù)，均勻，各向同性的線彈性材料，材料變形為彈性小變形。 3.2實(shí)體建模 利用電子計(jì)算機(jī)技術(shù)，按照實(shí)際尺寸，建立頜骨和微種植體的三維模型，形成裝配。 3.3網(wǎng)格劃分 利用電子計(jì)算機(jī)技術(shù)，導(dǎo)入三維模型到有限元建模軟件Hyperwork11.0的Hypermesh模塊中對模型進(jìn)行網(wǎng)格細(xì)化。 3.4部件連接 將有限元網(wǎng)格模型導(dǎo)入到Abaqus6.10中，建立各部分相應(yīng)的接觸面。 ４計(jì)算結(jié)果 利用Hyperworks11.0的Hyperview模塊查看計(jì)算結(jié)果，并采集各組的Von-Mises應(yīng)力值及位移值。分析微種植體-骨界面及微種植體的的應(yīng)力分布、應(yīng)變規(guī)律。 結(jié)果: 1建立了不同愈合時間下的微種植體-頜骨模型，其幾何相似性及生物力學(xué)相似性好，滿足力學(xué)運(yùn)算要求。 2微種植體上應(yīng)力及位移分布：所有工況下微種植體的Von-Mises應(yīng)力主要分布在其骨內(nèi)與皮質(zhì)骨接觸的區(qū)域；位移主要集中在骨外部分，骨內(nèi)部分主要集中在與皮質(zhì)骨接觸的區(qū)域。 3微種植體-骨界面的應(yīng)力及位移分布：頜骨內(nèi)所有工況Von-Mises應(yīng)力分布主要集中在皮質(zhì)骨范圍內(nèi)，應(yīng)力在其范圍內(nèi)迅速衰減，松質(zhì)骨范圍內(nèi)的應(yīng)力較�。籈L組和DL組，位移在皮質(zhì)骨范圍內(nèi)較為集中，在松質(zhì)骨內(nèi)迅速減�。欢贗L組，位移峰值分布在皮質(zhì)骨區(qū)域內(nèi)，但是位移的變化在整個頜骨內(nèi)呈現(xiàn)波浪形，波浪的頂點(diǎn)數(shù)值出現(xiàn)在每個螺紋的刃狀部。 4愈合時間對微種植體-骨界面應(yīng)力、位移的影響：IL組具有較高的應(yīng)力和位移峰值，EL組和DL組的應(yīng)力及位移峰值基本相同。說明在皮質(zhì)骨較薄的Ⅲ類骨質(zhì)中，34%的骨結(jié)合率即足以提供微種植體所需的穩(wěn)定性。 5不同過盈量對微種植體-骨界面應(yīng)力的影響：IL1~IL3組的應(yīng)力峰值可見過盈量的大小與微種植體-骨界面的應(yīng)力基本呈正相關(guān)，且對同一過盈量而言，不加載、加載1N或2Ｎ的力值，其應(yīng)力峰值并無變化。這說明在種植體植入初期，微種植體-骨界面的應(yīng)力基本由微種植體和骨的機(jī)械嵌合力提供，1N~2N的正畸加載對骨界面無明顯影響。 結(jié)論： 1微種植體-骨界面的應(yīng)力分布主要集中于皮質(zhì)骨范圍內(nèi)，松質(zhì)骨范圍內(nèi)的應(yīng)力較小； 2在種植體植入初期，微種植體-骨界面的應(yīng)力基本由微種植體和骨的機(jī)械嵌合力提供，1N~2N的正畸加載對骨界面無明顯影響。提示在Ⅲ類骨質(zhì)中可以進(jìn)行適量力值的即刻加載； 334%的骨結(jié)合率即可以提供微種植體所需的穩(wěn)定性； 4在Ⅲ類骨質(zhì)中減少載荷力值可以降低微種植體-骨界面應(yīng)力、位移峰值，使微種植體-骨界面應(yīng)力更加均勻，有利于微種植體的穩(wěn)定性。
[Abstract]:Objective: The control of the support in the course of orthodontic treatment is the key factor that affects the treatment effect. The microimplant has the advantages of simple operation, small wound, low cost and reliable curative effect, and has become a hot spot in the field of orthodontics in recent years. The premise of providing strong support for orthodontic treatment is the self-stability of the micro-implant, and the stability of the micro-implant is closely related to the quality of the jaw. The quality of the jaw has a large variation in the population. It is often found in the clinical application that some of the adolescents have a thin cortical bone, the initial stability of the implant is poor, the healing time and the adjustment of the load force value can improve the success rate of the implant. The retention form of the micro-implant is mainly composed of a mechanical block force and a biological combination. In the first stage of the implant implantation, the mechanical engagement force is mainly the friction between the micro-implant and the bone tissue without the formation of a bone union in the initial implantation stage of the implant. The force is provided. The biological combination is also divided into fiber-binding (there is a layer of non-mineralized fibrous connective tissue between the implant and the bone tissue), the bone union (the implant is in direct contact with the bone tissue, there is no bone other than the bone), Tissue to achieve direct contact between the implant and bone tissue in structure and function) and mixing The study shows that the healing time before microimplant loading can have a certain effect on its stability, but the optimal loading time There is still a dispute. The traditional view is that after the implant is implanted, a certain bone healing process should be guaranteed to be re-loaded in order to increase the bone-binding rate, thereby protecting the bone. In recent years, a new point of view is that a limited amount of micromotion of the implant in the early retention of the implant is beneficial to the bone union, which provides immediate loading of the microimplant. There are many methods to study the anchorage of the implant. In recent years, it is proved that the three-dimensional finite element is an effective method. The mechanical analysis method based on the three-dimensional finite element method can more accurately simulate the inside of the object. The three-dimensional finite element method is now widely used. in that field of orthodontics, a three-dimensional finite element method is used to establish a model of type III bone and an implant support model, The stress analysis of the model was carried out to observe and compare the effect of different healing time on the stability of the micro-implant and provide the theoretical basis for guiding the clinical application. and improve the success of planting Rate. Method:1 experimental device computer: desktop, (Intel (R) Xeon (R) CPU E5-1650, 3.20 GHz: 8G memory, win7, 64bit operating system) software package: Catia V5,Hyperwo rks11.0, Abaqu s6.10 2 micro The setting of the implant-jaw model: 2.1 The jaw model is established according to a female volunteer's second premolar on the left side of the maxilla and the first molar The maxilla CT profile of the implant site of the interdental implant and the model of the maxilla. The maxilla table The face is divided into cortical bone with a thickness of 0.7 mm and the inside is cancellous bone. According to the actual size, the section is simplified into the isosceles trapezoid, the section size: the upper surface 15 mm wide and 13.5 mm wide, 7.5 mm high. Then face The micro-implant model was established according to the clinical common orthodontic microimplant morphology. The data were as follows: total length of 12 mm, total length of intraosseous segment 8 mm, diameter of 1.6 mm, Thread height of 0.2 mm, edge-like thread top angle 60 deg., pitch 0.6 mm. 2.3 Assembly of micro-implant-maxillary solid model The jaw and the micro-implant are assembled in accordance with the corresponding position A micro-implant-jaw model was obtained.1 N and 2 N orthodontics were applied to the neck of the implant, respectively. Force. Set to the Gingival to the Y-axis positive, in the distal direction to the X-axis, and the long axis of the implant as the Z-axis. The loading direction is parallel to the X-axis. Y-plane (perpendicular to the implant The orthodontic force in the opposite direction to the Y-axis. Group Design: 2.4.1 Immediate Loading Group (Immediate Load, IL): simulating nonunion with coulomb friction model State, friction coefficient. mu. = 0.2. At the same time, the initial stress of the implant bone interface is simulated by an interference fit method. Load 1 (Immediate Loading1, IL1): set the interference amount to 0.03; Load 2 immediately (Immediate Loading2, IL2): set interference to 0.0 5; Load 3 immediately (Immediate Loading3, IL3): set the interference amount to 0.1;2 4.2.2 Early Loading (EL) and Delay Loading (DL): In the case of three weeks of healing and 7 weeks after healing, the micro-implant- bone-binding ratio (bone-i) mpla nt conta ct rate, BIC) defines two sets of micro-implant-bone contact surfaces: EL group: BIC = 34 % DL group: BIC = 44% by micro-planting Bone-binding and non-bone-binding in different proportions of the body-to-bone interface to simulate different microimplant-bone-binding ratios. The bone-binding and non-bone-binding regional intervals occur and are randomly assigned. The bone-binding region bone tissue and the implant interface the unit is the opposite of the load The displacement is 0, which is fixed contact; the interface unit of the non-bone joint area allows relative sliding under the action of external force, and the coefficient of friction is mu = 0.2. .3 Materials 3.1 Material properties assume that both the implant, the cortical bone, and the cancellous bone are continuous, uniform, isotropic the elastic material, the material, The deformation is an elastic small deformation. 3.2 The solid modeling uses the computer technology to establish a three-dimensional model of the jaw and the micro-implant according to the actual size to form the assembly. .3 Mesh division Using the computer technology, the three-dimensional model is introduced to the finite element modeling software Hyperwor1 1.0 H Mesh refinement of the model in the yermesh module. 3.4 Component connections import the finite element mesh model into the Abaqus6.10 and set up each part of the corresponding contact surface. The results of the calculation take advantage of the Hypershade rks 11.0 The Hyperview module looks at the calculation results and collects the Von-Mises stress values and the displacement values for each group. The stress distribution and the strain law of the micro-implant-bone interface and the micro-implant were established. Results:1 The micro-implant-jaw model with different healing time was established, the geometric similarity and the biomechanical similarity were good, and the mechanical operation requirement was satisfied. The stress and displacement distribution of the implant: The Von-Mises stress of the micro-implant in all working conditions is mainly distributed in the area in which the bone is in contact with the cortical bone; the displacement is mainly concentrated in the outer part of the bone, and the intra-osseous part is mainly concentrated in the area in contact with the cortical bone. The stress of the micro-implant-bone interface and displacement distribution: the stress distribution of the Von-Mises stress in all working conditions in the jaw is mainly concentrated in the cortical bone, the stress is rapidly attenuated in the range of the cortical bone, and the stress in the range of the cancellous bone is small; and the EL group and the DL In the group, the displacement is more concentrated in the cortical bone, and is rapidly reduced in the cancellous bone; in the IL group, the displacement peak is distributed in the cortical bone area, but the change of the displacement is within the whole jaw the wave is presented with the apex value of the wave occurring at the edge of each thread. The healing time is for the micro-implant-bone The effect of interface stress and displacement is that the stress and displacement peaks of the IL group have higher stress and displacement peak value, and the stress and displacement peaks of the EL group and the DL group are the same. The effect of the implant-bone interface stress: the stress peak of the IL1-IL3 group was positively correlated with the stress of the micro-implant-bone interface and the same amount of interference No, no, no, no. Loading, loading of 1N or 2N force values, and no change in the stress peak. This indicates that at the initial stage of implant implantation, the microspecies The stress of the bone-bone interface is basically provided by the mechanical block force of the micro-implant and the bone, and the orthodontic loading on the bone-bone interface is applied to the bone. There was no obvious effect on the interface. Conclusion:1 micro-implant -The stress distribution of the bone interface is mainly concentrated in the cortical bone. the stress in the implant range is small; at the initial stage of the implant implantation, the microspecies The stress of the bone-bone interface is basically provided by the mechanical block force of the micro-implant and the bone, and the stress of the bone-bone interface is 1-2N Orthodontic loading has no significant effect on the bone interface.
【學(xué)位授予單位】：河北醫(yī)科大學(xué)
【學(xué)位級別】：碩士
【學(xué)位授予年份】：2014
【分類號】：R783.6
[Abstract]:Objective: The control of the support in the course of orthodontic treatment is the key factor that affects the treatment effect. The microimplant has the advantages of simple operation, small wound, low cost and reliable curative effect, and has become a hot spot in the field of orthodontics in recent years. The premise of providing strong support for orthodontic treatment is the self-stability of the micro-implant, and the stability of the micro-implant is closely related to the quality of the jaw. The quality of the jaw has a large variation in the population. It is often found in the clinical application that some of the adolescents have a thin cortical bone, the initial stability of the implant is poor, the healing time and the adjustment of the load force value can improve the success rate of the implant. The retention form of the micro-implant is mainly composed of a mechanical block force and a biological combination. In the first stage of the implant implantation, the mechanical engagement force is mainly the friction between the micro-implant and the bone tissue without the formation of a bone union in the initial implantation stage of the implant. The force is provided. The biological combination is also divided into fiber-binding (there is a layer of non-mineralized fibrous connective tissue between the implant and the bone tissue), the bone union (the implant is in direct contact with the bone tissue, there is no bone other than the bone), Tissue to achieve direct contact between the implant and bone tissue in structure and function) and mixing The study shows that the healing time before microimplant loading can have a certain effect on its stability, but the optimal loading time There is still a dispute. The traditional view is that after the implant is implanted, a certain bone healing process should be guaranteed to be re-loaded in order to increase the bone-binding rate, thereby protecting the bone. In recent years, a new point of view is that a limited amount of micromotion of the implant in the early retention of the implant is beneficial to the bone union, which provides immediate loading of the microimplant. There are many methods to study the anchorage of the implant. In recent years, it is proved that the three-dimensional finite element is an effective method. The mechanical analysis method based on the three-dimensional finite element method can more accurately simulate the inside of the object. The three-dimensional finite element method is now widely used. in that field of orthodontics, a three-dimensional finite element method is used to establish a model of type III bone and an implant support model, The stress analysis of the model was carried out to observe and compare the effect of different healing time on the stability of the micro-implant and provide the theoretical basis for guiding the clinical application. and improve the success of planting Rate. Method:1 experimental device computer: desktop, (Intel (R) Xeon (R) CPU E5-1650, 3.20 GHz: 8G memory, win7, 64bit operating system) software package: Catia V5,Hyperwo rks11.0, Abaqu s6.10 2 micro The setting of the implant-jaw model: 2.1 The jaw model is established according to a female volunteer's second premolar on the left side of the maxilla and the first molar The maxilla CT profile of the implant site of the interdental implant and the model of the maxilla. The maxilla table The face is divided into cortical bone with a thickness of 0.7 mm and the inside is cancellous bone. According to the actual size, the section is simplified into the isosceles trapezoid, the section size: the upper surface 15 mm wide and 13.5 mm wide, 7.5 mm high. Then face The micro-implant model was established according to the clinical common orthodontic microimplant morphology. The data were as follows: total length of 12 mm, total length of intraosseous segment 8 mm, diameter of 1.6 mm, Thread height of 0.2 mm, edge-like thread top angle 60 deg., pitch 0.6 mm. 2.3 Assembly of micro-implant-maxillary solid model The jaw and the micro-implant are assembled in accordance with the corresponding position A micro-implant-jaw model was obtained.1 N and 2 N orthodontics were applied to the neck of the implant, respectively. Force. Set to the Gingival to the Y-axis positive, in the distal direction to the X-axis, and the long axis of the implant as the Z-axis. The loading direction is parallel to the X-axis. Y-plane (perpendicular to the implant The orthodontic force in the opposite direction to the Y-axis. Group Design: 2.4.1 Immediate Loading Group (Immediate Load, IL): simulating nonunion with coulomb friction model State, friction coefficient. mu. = 0.2. At the same time, the initial stress of the implant bone interface is simulated by an interference fit method. Load 1 (Immediate Loading1, IL1): set the interference amount to 0.03; Load 2 immediately (Immediate Loading2, IL2): set interference to 0.0 5; Load 3 immediately (Immediate Loading3, IL3): set the interference amount to 0.1;2 4.2.2 Early Loading (EL) and Delay Loading (DL): In the case of three weeks of healing and 7 weeks after healing, the micro-implant- bone-binding ratio (bone-i) mpla nt conta ct rate, BIC) defines two sets of micro-implant-bone contact surfaces: EL group: BIC = 34 % DL group: BIC = 44% by micro-planting Bone-binding and non-bone-binding in different proportions of the body-to-bone interface to simulate different microimplant-bone-binding ratios. The bone-binding and non-bone-binding regional intervals occur and are randomly assigned. The bone-binding region bone tissue and the implant interface the unit is the opposite of the load The displacement is 0, which is fixed contact; the interface unit of the non-bone joint area allows relative sliding under the action of external force, and the coefficient of friction is mu = 0.2. .3 Materials 3.1 Material properties assume that both the implant, the cortical bone, and the cancellous bone are continuous, uniform, isotropic the elastic material, the material, The deformation is an elastic small deformation. 3.2 The solid modeling uses the computer technology to establish a three-dimensional model of the jaw and the micro-implant according to the actual size to form the assembly. .3 Mesh division Using the computer technology, the three-dimensional model is introduced to the finite element modeling software Hyperwor1 1.0 H Mesh refinement of the model in the yermesh module. 3.4 Component connections import the finite element mesh model into the Abaqus6.10 and set up each part of the corresponding contact surface. The results of the calculation take advantage of the Hypershade rks 11.0 The Hyperview module looks at the calculation results and collects the Von-Mises stress values and the displacement values for each group. The stress distribution and the strain law of the micro-implant-bone interface and the micro-implant were established. Results:1 The micro-implant-jaw model with different healing time was established, the geometric similarity and the biomechanical similarity were good, and the mechanical operation requirement was satisfied. The stress and displacement distribution of the implant: The Von-Mises stress of the micro-implant in all working conditions is mainly distributed in the area in which the bone is in contact with the cortical bone; the displacement is mainly concentrated in the outer part of the bone, and the intra-osseous part is mainly concentrated in the area in contact with the cortical bone. The stress of the micro-implant-bone interface and displacement distribution: the stress distribution of the Von-Mises stress in all working conditions in the jaw is mainly concentrated in the cortical bone, the stress is rapidly attenuated in the range of the cortical bone, and the stress in the range of the cancellous bone is small; and the EL group and the DL In the group, the displacement is more concentrated in the cortical bone, and is rapidly reduced in the cancellous bone; in the IL group, the displacement peak is distributed in the cortical bone area, but the change of the displacement is within the whole jaw the wave is presented with the apex value of the wave occurring at the edge of each thread. The healing time is for the micro-implant-bone The effect of interface stress and displacement is that the stress and displacement peaks of the IL group have higher stress and displacement peak value, and the stress and displacement peaks of the EL group and the DL group are the same. The effect of the implant-bone interface stress: the stress peak of the IL1-IL3 group was positively correlated with the stress of the micro-implant-bone interface and the same amount of interference No, no, no, no. Loading, loading of 1N or 2N force values, and no change in the stress peak. This indicates that at the initial stage of implant implantation, the microspecies The stress of the bone-bone interface is basically provided by the mechanical block force of the micro-implant and the bone, and the orthodontic loading on the bone-bone interface is applied to the bone. There was no obvious effect on the interface. Conclusion:1 micro-implant -The stress distribution of the bone interface is mainly concentrated in the cortical bone. the stress in the implant range is small; at the initial stage of the implant implantation, the microspecies The stress of the bone-bone interface is basically provided by the mechanical block force of the micro-implant and the bone, and the stress of the bone-bone interface is 1-2N Orthodontic loading has no significant effect on the bone interface.
【學(xué)位授予單位】：河北醫(yī)科大學(xué)
【學(xué)位級別】：碩士
【學(xué)位授予年份】：2014
【分類號】：R783.6
【參考文獻(xiàn)】
相關(guān)期刊論文 前10條
1 鄭琳琳;劉s
本文編號：2508844
本文鏈接：http://sikaile.net/yixuelunwen/kouq/2508844.html
最近更新
教材專著
