Comparative assessment of relapse and failure between CAD/CAM stainless steel and standard stainless steel fixed retainers in orthodontic retention patients:: A randomized controlled trial

ObjectivesTo compare relapse and failure rates of computer-aided design/computer-aided manufacturing (CAD/CAM) and standard fixed retainers.Materials and MethodsThis single-center, single-blinded, prospective randomized clinical trial included 46 patients who completed active orthodontic treatment and complied with retention visits. The patients were randomly assigned to three groups: CAD/CAM group with multistranded stainless steel wires (CAD/CAM, n = 16), Lab group with the same multistranded wires (lab, n = 16), and control group with stainless steel Ortho-FlexTech wires (traditional, n = 14). Intraoral scans were obtained at placement of fixed retainers (T1), 3-month visit (T2), and 6-month visit (T3) and measured for intercanine width and Little''s Irregularity Index. Failures were recorded.ResultsThe CAD/CAM group experienced less intercanine width decrease than the traditional group at 3 months (mean difference, 0.83 ± 0.16 mm; 95% confidence interval [CI], 0.44–1.22; P < .001) and 6 months (mean difference, 1.23 ± 0.40 mm; 95% CI, 0.19–2.27; P < .05). The CAD/CAM group experienced less increase in Little''s Irregularity Index compared with the lab group within 3 months (mean difference, 0.81 ± 0.27 mm; 95% CI, 0.12–1.49; P < .05). Failures from greatest to least were experienced by the lab group (43.8%), the CAD/CAM group (25%), and the traditional group (14.3%).ConclusionsWithin 6 months of bonding fixed retainers, CAD/CAM fixed retainers showed less relapse than lab-based and traditional chairside retainers and less failures than lab-based retainers.     

Effect of Enamel Pretreatment with Pastes Presenting Different Relative Dentin Abrasivity (RDA) Values on Orthodontic Bracket Bonding Efficacy of Microfilled Composite Resin: In Vitro Investigation and Randomized Clinical Trial

Bonding failure is a clinical issue frequently encountered in orthodontic practice. The aim of this study was to evaluate enamel pretreatment both in vitro and clinically using agents with different RDA values before brackets’ bonding, to assess if RDA can affect the Shear Bond Strength (SBS), Adhesive Remnant Index (ARI) and clinical failure rate of orthodontic brackets. For the in vitro study, 220 bovine teeth were pretreated with agents with different RDA values. Subsequently, brackets were bonded. For the clinical study, 20 patients underwent bonding of 20 brackets each with a split-mouth design. Low and high RDA toothpastes were used for enamel pretreatment. SBS, ARI and failures were recorded. Higher SBS values were found for teeth pretreated with lower RDA agents; conversely, lower SBS values were found for teeth pretreated with higher RDA agents (p < 0.05). For high ARI values, RDA increased too (p > 0.05). In the clinical study, a significantly lower failure rate was reported for teeth pretreated with low RDA toothpaste (2.5% in low RDA group, 7.0% in high RDA group; p < 0.05). No significant differences were assessed comparing the two dental arches and anterior and posterior sites. Enamel pretreatment with low RDA toothpastes could increase brackets’ survival rate. Further in vitro and clinical studies would be welcomed to confirm these findings.     

牙-牙槽骨联合移植修复牙列缺损的临床应用研究

目的 评价牙-牙槽骨联合移植修复牙列缺损的临床效果。方法 将45例牙列缺损患者根据牙移植手术方法不同分为2组：A组24例,采用改良的外科正牙手术方法,在供区移植牙周围牙槽骨内切取牙-牙槽骨的复合体,在受区预备相应的洞型后,植入牙-牙槽骨复合体;B组21例,采用常规牙移植方法,取出移植牙,制备植牙窝,植入供牙。2组正畸固定4~6周,术后2~12周选择性根管治疗,定期随访观察,对临床效果进行评价。结果 2组移植牙在牙冠色泽变化以及牙周膜影像等方面无统计学差异（P>0.05）,在松动度、牙根吸收、根管治疗比率、牙槽骨吸收等方面有统计学差异（P<0.05）,A组疗效优于B组。结论 牙-牙槽骨移植克服了传统牙移植的部分缺点,可作为牙列缺损的修复方法之一。     

个体化舌侧矫治器的初步实验研究

目的 探讨采用计算机辅助设计与计算机辅助制造(CAD/CAM)方法制造个体化舌侧矫治器的可行性.方法运用三维激光扫描仪采集与重建牙颌模型数据,并以该数字模型为基础,应用三维软件进行个体化舌侧托槽的CAD,通过快速成型与铸造技术将CAD托槽转化制作为个体化舌侧金属托槽,再根据CAD个体化弓形图弯制个体化弓丝.结果三维激光...     

骨性Ⅱ类高角型开[牙合]拔除上颌第一前磨牙及下颌第二磨牙矫治的临床研究

目的用回顾分析方法,评价拔除上颌第一前磨牙及下颌第二磨牙矫治骨性Ⅱ类高角型开[牙合]的临床疗效。方法选取12例骨性Ⅱ类开[牙合]病例,男4例,女8例,平均年龄15.6岁,拔除上颌第一前磨牙及下颌第二磨牙后,使用直丝弓矫治技术对其进行矫正治疗。治疗前后拍摄X线头颅侧位片,并对其进行头影测量分析。结果矫正治疗结束后,12例患者均取得了满意的治疗效果,侧貌明显改善,覆[牙合]覆盖正常,[牙合]平面发生逆时针旋转,下颌平面角变小。结论拔除上颌第一前磨牙及下颌第二磨牙矫治骨性Ⅱ类开[牙合]临床疗效可靠,效果较稳定。     

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目的观察姑息正畸治疗对重度牙周病前牙错位的疗效。方法选择2006年1月至2010年12月在首都医科大学口腔医学院正畸科和牙周科接诊的重度慢性牙周病导致的前牙伸长、唇向倾斜、牙间隙增宽等移位的患者20例为研究对象,采用牙周基础治疗联合正畸治疗,总结分析其治疗效果。结果治疗后患者的移位牙齿复位良好,排列整齐,间隙关闭,覆[牙合]手舍覆盖正常;患牙松动度明显减小,牙周探诊深度、出血指数虽无明显改善,亦未加重。结论对于重度牙周病患牙在患者拒绝拔除时可试行姑息正畸治疗,可在一定时期内改善咬合功能及容貌美观．延缓牙齿脱落。     

中国汉族成人正常（牙合）牙体舌侧形态的测量研究

对中国汉族年轻成人正常（牙合）牙齿的舌侧形态进行三维测量,为研发基于中国人牙体舌侧形态的舌侧直丝弓托槽提供数据参考。方法：采用上海正雅齿科科技有限公司开发的数字化正畸设计系统软件,对普查获得的64副中国汉族正常（牙合）个体的牙齿模型进行三维扫描,并对三维数字模型舌侧面进行计算机定点及测量分析。结果：获得正常（牙合）人群牙齿舌侧的轴倾度、转矩角、冠凸距和尖牙与磨牙补偿角指标的参考值,与国内相关研究结果相近。结论：本研究的测量结果可用于研发中国人舌侧直丝弓托槽标准型。     

青少年女性月经周期不同阶段加力对正畸牙移动的影响

背景：雌激素对正畸牙齿移动有影响,目前仅有动物实验证明,雌激素水平越低,正畸牙移动量越大,雌激素水平越高,正畸牙移动量越小。 目的：分析青少年女性正畸患者月经周期的不同时期加力对正畸牙移动的影响。 方法：选取12例14-18岁已具有月经初潮,月经规律,需要拔除上颌第1前磨牙的女性患者。采取自身对照,将患者上颌左右两侧尖牙,随机分为月经期加力组和排卵期加力组,应用种植体支抗加力远中移动尖牙,月经期加力组加力2周后排卵期加力组开始加力。各组分别于加力即刻及4周时取模,灌制超硬石膏模型,测量各组尖牙向远中移动的距离,采用GraphPad Prism5软件包对数据进行统计学分析。 结果与结论：月经期加力组尖牙移动量大于排卵期加力组（P〈0.05）。提示青少年女性正畸患者在月经期加力正畸牙的移动速度较排卵期正畸牙的移动速度显著增加,可有效缩短正畸矫治疗程。     

个性化舌侧矫治对牙周健康的影响

目的 研究成人个性化舌侧矫治对牙周健康的影响.方法 选择成人正畸患者8例共48个牙位点,根据错(牙合)畸形程度分为两组,粘结舌侧矫治器附件的单颌牙齿作为实验组,暂时不粘结舌侧矫治器附件的对颌牙齿作为对照组.在矫治前、矫治2个月、矫治6个月、矫治结束后1个月对牙龈指数(GI)、出血指数 (BI)、菌斑指数(PLI)等变化进行检测,并对数据进行统计分析;以上述8例患者作为舌侧矫治组,另选8例唇侧矫治患者,研究唇、舌侧矫治牙周临床检测指标的差异.结果 个性化舌侧矫治的实验组与对照组及矫治之前相比,矫治2个月及6个月后,GI、BI、PLI升高(P<0.05),矫治结束后1个月,PLI升高(P<0.05),GI、BI差异无统计学意义;唇、舌侧矫治结束后两组间GI、BI、PLI差异无统计学意义.结论 舌侧矫治会使成人菌斑指数升高,当患者形成正确的牙周健康理念、牙周维护较好时,不会引起牙龈和牙周炎症,其为个性化舌侧矫治普遍运用于临床提供理论依据.     

重度侵袭性牙周炎正畸种植修复联合治疗的临床修复效果1例报告及文献复习

探讨侵袭性牙周炎患者经口腔多学科联合治疗后的临床修复效果,阐述多学科联合治疗对口腔功能恢复的重要意义。