目的探讨生物陶瓷iRoot BP Plus活髓切断即刻修复术对年轻恒牙冠折患儿牙体功能及美观的影响。方法选取2022年5月至2024年5月本院收治的120例年轻恒牙冠折患儿作为研究对象,按随机数字表法分为两组各60例。对照组行传统氢氧化钙活髓切...目的探讨生物陶瓷iRoot BP Plus活髓切断即刻修复术对年轻恒牙冠折患儿牙体功能及美观的影响。方法选取2022年5月至2024年5月本院收治的120例年轻恒牙冠折患儿作为研究对象,按随机数字表法分为两组各60例。对照组行传统氢氧化钙活髓切断联合延迟修复术,观察组行iRoot BP Plus活髓切断联合即刻修复术。比较两组的临床疗效、牙体功能指标、美观度、不良反应。结果观察组的治疗总有效率为93.33%,高于对照组的78.33%(P<0.05)。观察组术后12个月的咀嚼效率评分高于对照组,牙周袋深度(PD)、牙龈指数(GI)、龈沟出血指数(SBI)均低于对照组(P<0.05)。观察组的牙齿色泽匹配优良率为91.67%,高于对照组的76.67%(P<0.05)。观察组的不良反应总发生率为5.00%,低于对照组的16.67%(P<0.05)。结论生物陶瓷iRoot BP Plus活髓切断即刻修复术治疗年轻恒牙冠折能有效保存患牙活髓,促进牙根继续发育,改善患牙咀嚼功能和牙周健康状况,且美学效果更佳,不良反应少。展开更多
Based on Newton ' s second law,the bend-torsion-shaft coupling nonlinear dynamic model and equations of power split gear transmission system are established.According to the principle of tooth profile modification...Based on Newton ' s second law,the bend-torsion-shaft coupling nonlinear dynamic model and equations of power split gear transmission system are established.According to the principle of tooth profile modification,the tooth profile modification is considered as time-varying gear backlash function acting along the line of action.Then the dynamic functions are solved by using Runge-Kutta numerical method.After analyzing the effect of tooth profile modification quantity( TPMQ) and relative tooth profile modification length( TPML) to the nonlinear dynamic characteristics of power split gear transmission,the following conclusions are drawn:1 The TPMQ of a certain stage transmission affects the vibration of its own stage more significantly than the other stage,and the coupling effect between two stages can be ignored usually in the modification design;2 If the first stage TPMLs are less than 0.3,the influence of the first stage TPMLs to the first stage transmission vibration is much more greatly than the influence of the second stage TPMLs to the first stage transmission vibration,or else both the first and second stage TPMLs affect the first stage transmission vibration largely.The same is true for the second stage TPMLs,and the cutoff value is 0.2;3 The TPMQ affects the vibration of power split gear transmission system more principally than the TPML,and should be top-priority in the modification design.展开更多
文摘目的探讨生物陶瓷iRoot BP Plus活髓切断即刻修复术对年轻恒牙冠折患儿牙体功能及美观的影响。方法选取2022年5月至2024年5月本院收治的120例年轻恒牙冠折患儿作为研究对象,按随机数字表法分为两组各60例。对照组行传统氢氧化钙活髓切断联合延迟修复术,观察组行iRoot BP Plus活髓切断联合即刻修复术。比较两组的临床疗效、牙体功能指标、美观度、不良反应。结果观察组的治疗总有效率为93.33%,高于对照组的78.33%(P<0.05)。观察组术后12个月的咀嚼效率评分高于对照组,牙周袋深度(PD)、牙龈指数(GI)、龈沟出血指数(SBI)均低于对照组(P<0.05)。观察组的牙齿色泽匹配优良率为91.67%,高于对照组的76.67%(P<0.05)。观察组的不良反应总发生率为5.00%,低于对照组的16.67%(P<0.05)。结论生物陶瓷iRoot BP Plus活髓切断即刻修复术治疗年轻恒牙冠折能有效保存患牙活髓,促进牙根继续发育,改善患牙咀嚼功能和牙周健康状况,且美学效果更佳,不良反应少。
基金Sponsored by the National Natural Science Foundation of China(Grant No.2009AA04Z404)
文摘Based on Newton ' s second law,the bend-torsion-shaft coupling nonlinear dynamic model and equations of power split gear transmission system are established.According to the principle of tooth profile modification,the tooth profile modification is considered as time-varying gear backlash function acting along the line of action.Then the dynamic functions are solved by using Runge-Kutta numerical method.After analyzing the effect of tooth profile modification quantity( TPMQ) and relative tooth profile modification length( TPML) to the nonlinear dynamic characteristics of power split gear transmission,the following conclusions are drawn:1 The TPMQ of a certain stage transmission affects the vibration of its own stage more significantly than the other stage,and the coupling effect between two stages can be ignored usually in the modification design;2 If the first stage TPMLs are less than 0.3,the influence of the first stage TPMLs to the first stage transmission vibration is much more greatly than the influence of the second stage TPMLs to the first stage transmission vibration,or else both the first and second stage TPMLs affect the first stage transmission vibration largely.The same is true for the second stage TPMLs,and the cutoff value is 0.2;3 The TPMQ affects the vibration of power split gear transmission system more principally than the TPML,and should be top-priority in the modification design.
