持续或间断应力载荷下正畸微种植体稳定性的组织形态学和生物力学评价
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摘要
背景:在正畸治疗过程中,很多学者认为间断力相比持续力能获得同等甚至更大的牙移动疗效,并可减少牙根吸收等不良反应的发生,然而上述结论多来自体外细胞实验或临床个案观察,尚缺少设计科学合理、规模较大的动物实验。目的:分析持续应力或两种模式间断应力载荷对正畸微种植体骨整合及生物稳定性的影响。方法:取48只Beagle犬(四川大学实验动物中心提供),在下颌骨两侧第一磨牙和第二前磨牙的根间区域各植入1枚微种植体(每只犬共植入4枚微种植体),随机分4组:持续组每个加载周期连续加载应力,间断A组在每个加载周期的最后3 d中断应力,间断B组在每个加载周期的最后7 d中断应力,以未加力组为对照。应力加载方法与周期:通过结扎丝在同侧2个微种植体安装镍钛螺旋拉簧,实施加载力;设置1个加载周期为2周,共加载4个周期。加载2,4,6,8周后,获取各组下颌骨组织,进行显微CT、组织学观察和力学拉拔测试。实验方案经过四川大学实验动物伦理委员会批准。结果与结论:①未加力组加载不同时间点的峰值拉拔力均高于持续组(P <0.05),间断B组加载2,4,6周后的峰值拉拔力均高于持续组(P <0.05),间断A组加载2周后的峰值拉拔力均高于持续组(P <0.05);②显微CT显示相同加载时间点下,未加力组骨整合、骨体积分数、相交表面均高于持续组(P <0.05);间断B组加载2,4,6,8周后的骨整合、骨体积分数高于持续组(P<0.05),加载2,4,6周后的相交表面高于持续组(P <0.05);间断A组加载2,4周后的骨整合高于持续组(P <0.05),加载2,4,6周后的骨体积分数高于持续组(P <0.05),加载2周的相交表面高于持续组(P <0.05);③加载8周后,各组均可见骨重塑现象,骨重塑由好到差的排序依次为:未加力组、间断B组、间断A组、持续组;④结果表明,间断应力相比持续应力加载更有利于微种植体获得良好的稳定性,且7 d/7 d间断加载周期较11 d/3 d方案更能促进骨-微种植体结合。
BACKGROUND: During the orthodontic treatment process, many scholars believe that intermittent force can achieve the same or even greater effect of tooth movement than persistent force, and reduce the occurrence of root resorption and other adverse reactions. However,the above conclusions are mostly from in vitro cell experiments or clinical case study, and there is still a lack of scientifically designed and large-scale animal experiments.OBJECTIVE: To evaluate the influence of continuous or intermittent force of two modes on osseointegration and biostability of orthodontic micro-implant.METHODS: Forty-eight beagles(provided by Laboratory Animal Center of Sichuan University) were selected and mini-implants were implanted bilaterally in intraradicular zones of mandibular first molar and second premolar. The beagles were randomly allotted into four groups: loadings were delivered consecutively in continuous group, and pauses were given for the last 3 or 7 days of each reactivation period for intermittent group A and B, respectively. The group unloaded served as control. Loading protocol and period: loading force was applied by installing nickel-titanium closed coil springs on two mini-implants with ligating wires, and 2-week was set as a loading period, for 4 periods.After 2, 4, 6 and 8 weeks, the mandible tissues were obtained for micro-CT, histological observation and pull-out test. The study was approved by the Experimental Animal Ethics Committee of Sichuan University.RESULTS AND CONCLUSION:(1) The values of peak load at extraction(Fmax) at various loading time points in the control group were higher than those in the continuous group(P < 0.05). Fmax of the intermittent group B was higher than that in the continuous group at week 2, 4 and 6(P < 0.05); and the Fmax at week 2 in the intermittent group A was higher than the continuous group(P < 0.05).(2) At the same loading time point, the ossointegration, bone volume/tissue volume and intersection surface in the unloaded control were higher than those in the continuous group(P < 0.05). The ossointegration and bone volume/tissue volume in the intermittent group B at 2, 4, 6 and 8 weeks were higher than those in the continuous group(P < 0.05). At 2, 4 and 6 weeks, the intersection surface was higher than in the continuous group(P < 0.05). The ossointegration in the intermittent group A at 2 and 4 weeks was higher than that in the continuous group(P < 0.05).The bone volume/tissue volume was higher than in the continuous group at 2, 4 and 6 weeks(P < 0.05). The intersection surface was higher than in the continuous group at 2 weeks(P < 0.05).(3) Bone remodeling was observed in all groups after 8 weeks of loading, and the bone remodeling was best in the unloaded control group, followed by intermittent groups B and A and poorest in the continuous group.(4) In summary,intermittent loading regimen is more favorable for obtaining stability than continuous force, and the 7-day/7-day loading cycle is more beneficial for bone-implant integration than the 11-day/3-day protocol.
BACKGROUND: During the orthodontic treatment process, many scholars believe that intermittent force can achieve the same or even greater effect of tooth movement than persistent force, and reduce the occurrence of root resorption and other adverse reactions. However,the above conclusions are mostly from in vitro cell experiments or clinical case study, and there is still a lack of scientifically designed and large-scale animal experiments.OBJECTIVE: To evaluate the influence of continuous or intermittent force of two modes on osseointegration and biostability of orthodontic micro-implant.METHODS: Forty-eight beagles(provided by Laboratory Animal Center of Sichuan University) were selected and mini-implants were implanted bilaterally in intraradicular zones of mandibular first molar and second premolar. The beagles were randomly allotted into four groups: loadings were delivered consecutively in continuous group, and pauses were given for the last 3 or 7 days of each reactivation period for intermittent group A and B, respectively. The group unloaded served as control. Loading protocol and period: loading force was applied by installing nickel-titanium closed coil springs on two mini-implants with ligating wires, and 2-week was set as a loading period, for 4 periods.After 2, 4, 6 and 8 weeks, the mandible tissues were obtained for micro-CT, histological observation and pull-out test. The study was approved by the Experimental Animal Ethics Committee of Sichuan University.RESULTS AND CONCLUSION:(1) The values of peak load at extraction(Fmax) at various loading time points in the control group were higher than those in the continuous group(P < 0.05). Fmax of the intermittent group B was higher than that in the continuous group at week 2, 4 and 6(P < 0.05); and the Fmax at week 2 in the intermittent group A was higher than the continuous group(P < 0.05).(2) At the same loading time point, the ossointegration, bone volume/tissue volume and intersection surface in the unloaded control were higher than those in the continuous group(P < 0.05). The ossointegration and bone volume/tissue volume in the intermittent group B at 2, 4, 6 and 8 weeks were higher than those in the continuous group(P < 0.05). At 2, 4 and 6 weeks, the intersection surface was higher than in the continuous group(P < 0.05). The ossointegration in the intermittent group A at 2 and 4 weeks was higher than that in the continuous group(P < 0.05).The bone volume/tissue volume was higher than in the continuous group at 2, 4 and 6 weeks(P < 0.05). The intersection surface was higher than in the continuous group at 2 weeks(P < 0.05).(3) Bone remodeling was observed in all groups after 8 weeks of loading, and the bone remodeling was best in the unloaded control group, followed by intermittent groups B and A and poorest in the continuous group.(4) In summary,intermittent loading regimen is more favorable for obtaining stability than continuous force, and the 7-day/7-day loading cycle is more beneficial for bone-implant integration than the 11-day/3-day protocol.
引文
[1]Branemark PI,Aspegren K,Breine U.Microcirculatory studies in man by high resolution vital microscopy.Angiology.1964;15:329-332.
[2]Buser D,Mericske-Stern R,Bernard JP,et al.Long-term evaluation of nonsubmerged ITI implants.Part 1:8-year life table analysis of a prospective multicenter study with 2359implants.Clin Oral Implants Res.1997;8:161-172.
[3]Albrektsson T,Dahl E,Enbom L,et al.Osseointegrated oral implants.A Swedish multicenter study of 8139 consecutively inserted Nobel pharma implants.J Periodontol.1988;59:287-296.
[4]van Roekel NB.The use of Branemark system implants for orthodontics anchorages:report of a case.Int J Oral Maxillofac Implants.1989;4:341-344.
[5]Deguchi T,Takano-Yamamoto T,Kanomi R,et al.The use of small titanium screws for orthodontic anchorage.J Dent Res2003;82:377-381.
[6]Miyawaki S,Koyama I,Inoue M,et al.Factors associated with the stability of titanium screws placed in the posterior region for orthodontic anchorage.Am J Orthod Dentofacial Orthop.2003;124:373-378.
[7]Papageorgiou SN,Zogakis IP,Papadopoulosc MA.Failure rates and associated risk factors of orthodontic miniscrew implants:a meta-analysis.Am J Orthod Dentofacial Orthop.2012;142:577-595.
[8]Szmukler-Moncler S,Salama H,Reingewirtz Y,et al.Timing of loading and effect of micromotion on bone-dental implant interface:review of experimental literature.J Biomed Mater Res.1998;43:192-203.
[9]Isaacson JR,Ingram AH.Forces produced by rapid maxillary expansion.II.Forces present during treatment.Angle Orthod.1964;34:261-269.
[10]Krishnana V,Davidovitchb Z.Cellular,molecular,and tissue-level reactions to orthodontic force.Am J Orthod Dentofacial Orthop.2006;129:469.e1-469.e32.
[11]Southard KA,Forbes DP.The effects of force magnitude on a sutural model:a quantitative approach.Am J Orthod Dentofacial Orthop.1988;93:460-466.
[12]Deguchi T,Murakami T,Kuroda S,et al.Comparison of the intrusion effects on the maxillary incisors between implant anchorage and J-hook headgear.Am J Orthod Dentofacial Orthop.2008;133:654-660.
[13]Liu SS,Kyung HM,Buschang PH.Continuous forces are more effective than intermittent forces in expanding sutures.Eur JOrthod.2010;32:371-380.
[14]Saxon LK,Robling AG,Alam I,et al.Mechanosensitivity of the rat skeleton decreases after a long period of loading,but is improved with time off.Bone.2005;36:454-464.
[15]Robling AG,Burr DB,Turner CH.Recovery periods restore mechanosensitivity to dynamically loaded bone.J Exp Biol.2001;204(Pt 19):3389-3399.
[16]Kumasako-Haga T,Konoo T,Yamaguchi K,et al.Effect of 8-hour intermittent orthodontic force on osteoclasts and root resorption.Am J Orthod Dentofacial Orthop.2009;135:278.e1-278.e8.
[17]Aras B,Cheng LL,Turk T,et al.Physical properties of root cementum:part 23.Effects of 2 or 3 weekly reactivated continuous or intermittent orthodontic forces on root resorption and tooth movement:a microcomputed tomography study.Am J Orthod Dentofacial Orthop.2012;141:e29-e37.
[18]Ballard DJ,Jones AS,Petocz P,et al.Physical properties of root cementum:part 11.Continuous vs intermittent controlled orthodontic forces on root resorption.A microcomputedtomography study.Am J Orthod Dentofacial Orthop.2009;136(1):8.e1-8.e8.
[19]Zhao L,Xu Z,Yang Z,et al.Quantitative research using computed tomographic scanning of beagle jaws for determination of safe zones for micro-screw implantation.Ann Anat.2009;191(4):379-388.
[20]Xu Z,Wu,Zhao L,et al.Effect of placement angle on the stability of loaded titanium microscrews in beagle jaws.Angle Orthod.2013;83:659-666.
[21]Gabet Y,Muller R,Regev E,et al.Osteogenic growth peptide modulates fracture callus structural and mechanical properties.Bone.2004;35:65-73.
[22]Miura F,Mogi M,Ohura Y,et al.The super-elastic Japanese NiTi alloy wire for use in orthodontics.Part III.Studies on the Japanese NiTi alloy coil springs.Am J Orthod Dentofacial Orthop.1988;94:89-96.
[23]von Fraunhofer JA,Bonds PW,Johnson BE.Force generation by orthodontic coils prings.Angle Orthod 1993;63(2):145-148.
[24]Creekmore TD,Eklund MK.The possibility of skeletal anchorage.J Clin Orthod.1983;17:266-269.
[25]Kyung HM,Park HS,Bae SM,et al.Development of orthodontic micro-implants for intraoral anchorage.J Clin Orthod.2003;37:321-328.
[26]Zhao L,Xu Z,Yang Z,et al.Orthodontic mini-implant stability in different healing times before loading:a microscopic computerized tomographic and biomechanical analysis.Oral Surg Oral Med Oral Pathol Oral Radiol Endod.2009;108(2):196-202.
[27]Soncini M,Rodriguezy Baena R,et al.Experimental procedure for the evaluation of the mechanical properties of the bone surrounding dental implants.Biomaterials.2002;23(1):9-17.
[28]Melsen B,Costa A.Immediate loading of implants used for orthodontic anchorage.Clin Orthod Res.2000;3(1):23-28.
[29]Kim SH,Choi BH,Li JX,et al.Peri-implant bone reactions at delayed and immediately loaded implants:an experimental study.Oral Surg Oral Med Oral Pathol Oral Radiol Endod.2008;105:144-148.
[30]Schatzker J,Horne JG,Sumner-Smith G.The effect of movement on the holding power of screws in bone.Clin Orthop.1975;(111):257-262.
[31]Turner CH.Three rules for bone adaptation to mechanical stimuli.Bone.1998;23:399-407.
[32]Robling AG,Burr DB,Turner CH.Partitioning a daily mechanical stimulus into discrete loading bouts improves the osteogenic response to loading.J Bone Miner Res.2000;15(8):1596-1602.
[33]Srinivasan S,Agans SC,King KA,et al.Enabling bone formation in the aged skeleton via rest-inserted mechanical loading.Bone.2003;33(6):946-955.
[2]Buser D,Mericske-Stern R,Bernard JP,et al.Long-term evaluation of nonsubmerged ITI implants.Part 1:8-year life table analysis of a prospective multicenter study with 2359implants.Clin Oral Implants Res.1997;8:161-172.
[3]Albrektsson T,Dahl E,Enbom L,et al.Osseointegrated oral implants.A Swedish multicenter study of 8139 consecutively inserted Nobel pharma implants.J Periodontol.1988;59:287-296.
[4]van Roekel NB.The use of Branemark system implants for orthodontics anchorages:report of a case.Int J Oral Maxillofac Implants.1989;4:341-344.
[5]Deguchi T,Takano-Yamamoto T,Kanomi R,et al.The use of small titanium screws for orthodontic anchorage.J Dent Res2003;82:377-381.
[6]Miyawaki S,Koyama I,Inoue M,et al.Factors associated with the stability of titanium screws placed in the posterior region for orthodontic anchorage.Am J Orthod Dentofacial Orthop.2003;124:373-378.
[7]Papageorgiou SN,Zogakis IP,Papadopoulosc MA.Failure rates and associated risk factors of orthodontic miniscrew implants:a meta-analysis.Am J Orthod Dentofacial Orthop.2012;142:577-595.
[8]Szmukler-Moncler S,Salama H,Reingewirtz Y,et al.Timing of loading and effect of micromotion on bone-dental implant interface:review of experimental literature.J Biomed Mater Res.1998;43:192-203.
[9]Isaacson JR,Ingram AH.Forces produced by rapid maxillary expansion.II.Forces present during treatment.Angle Orthod.1964;34:261-269.
[10]Krishnana V,Davidovitchb Z.Cellular,molecular,and tissue-level reactions to orthodontic force.Am J Orthod Dentofacial Orthop.2006;129:469.e1-469.e32.
[11]Southard KA,Forbes DP.The effects of force magnitude on a sutural model:a quantitative approach.Am J Orthod Dentofacial Orthop.1988;93:460-466.
[12]Deguchi T,Murakami T,Kuroda S,et al.Comparison of the intrusion effects on the maxillary incisors between implant anchorage and J-hook headgear.Am J Orthod Dentofacial Orthop.2008;133:654-660.
[13]Liu SS,Kyung HM,Buschang PH.Continuous forces are more effective than intermittent forces in expanding sutures.Eur JOrthod.2010;32:371-380.
[14]Saxon LK,Robling AG,Alam I,et al.Mechanosensitivity of the rat skeleton decreases after a long period of loading,but is improved with time off.Bone.2005;36:454-464.
[15]Robling AG,Burr DB,Turner CH.Recovery periods restore mechanosensitivity to dynamically loaded bone.J Exp Biol.2001;204(Pt 19):3389-3399.
[16]Kumasako-Haga T,Konoo T,Yamaguchi K,et al.Effect of 8-hour intermittent orthodontic force on osteoclasts and root resorption.Am J Orthod Dentofacial Orthop.2009;135:278.e1-278.e8.
[17]Aras B,Cheng LL,Turk T,et al.Physical properties of root cementum:part 23.Effects of 2 or 3 weekly reactivated continuous or intermittent orthodontic forces on root resorption and tooth movement:a microcomputed tomography study.Am J Orthod Dentofacial Orthop.2012;141:e29-e37.
[18]Ballard DJ,Jones AS,Petocz P,et al.Physical properties of root cementum:part 11.Continuous vs intermittent controlled orthodontic forces on root resorption.A microcomputedtomography study.Am J Orthod Dentofacial Orthop.2009;136(1):8.e1-8.e8.
[19]Zhao L,Xu Z,Yang Z,et al.Quantitative research using computed tomographic scanning of beagle jaws for determination of safe zones for micro-screw implantation.Ann Anat.2009;191(4):379-388.
[20]Xu Z,Wu,Zhao L,et al.Effect of placement angle on the stability of loaded titanium microscrews in beagle jaws.Angle Orthod.2013;83:659-666.
[21]Gabet Y,Muller R,Regev E,et al.Osteogenic growth peptide modulates fracture callus structural and mechanical properties.Bone.2004;35:65-73.
[22]Miura F,Mogi M,Ohura Y,et al.The super-elastic Japanese NiTi alloy wire for use in orthodontics.Part III.Studies on the Japanese NiTi alloy coil springs.Am J Orthod Dentofacial Orthop.1988;94:89-96.
[23]von Fraunhofer JA,Bonds PW,Johnson BE.Force generation by orthodontic coils prings.Angle Orthod 1993;63(2):145-148.
[24]Creekmore TD,Eklund MK.The possibility of skeletal anchorage.J Clin Orthod.1983;17:266-269.
[25]Kyung HM,Park HS,Bae SM,et al.Development of orthodontic micro-implants for intraoral anchorage.J Clin Orthod.2003;37:321-328.
[26]Zhao L,Xu Z,Yang Z,et al.Orthodontic mini-implant stability in different healing times before loading:a microscopic computerized tomographic and biomechanical analysis.Oral Surg Oral Med Oral Pathol Oral Radiol Endod.2009;108(2):196-202.
[27]Soncini M,Rodriguezy Baena R,et al.Experimental procedure for the evaluation of the mechanical properties of the bone surrounding dental implants.Biomaterials.2002;23(1):9-17.
[28]Melsen B,Costa A.Immediate loading of implants used for orthodontic anchorage.Clin Orthod Res.2000;3(1):23-28.
[29]Kim SH,Choi BH,Li JX,et al.Peri-implant bone reactions at delayed and immediately loaded implants:an experimental study.Oral Surg Oral Med Oral Pathol Oral Radiol Endod.2008;105:144-148.
[30]Schatzker J,Horne JG,Sumner-Smith G.The effect of movement on the holding power of screws in bone.Clin Orthop.1975;(111):257-262.
[31]Turner CH.Three rules for bone adaptation to mechanical stimuli.Bone.1998;23:399-407.
[32]Robling AG,Burr DB,Turner CH.Partitioning a daily mechanical stimulus into discrete loading bouts improves the osteogenic response to loading.J Bone Miner Res.2000;15(8):1596-1602.
[33]Srinivasan S,Agans SC,King KA,et al.Enabling bone formation in the aged skeleton via rest-inserted mechanical loading.Bone.2003;33(6):946-955.
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