Measurement and comparison of bracket transfer accuracy of five indirect bonding techniques

Objective:To measure and compare bracket transfer accuracy of five indirect bonding (IDB) techniques.Materials and Methods:Five IDB techniques were studied: double polyvinyl siloxane (double-PVS), double vacuum-form (double-VF), polyvinyl siloxane vacuum-form (PVS-VF), polyvinyl siloxane putty (PVS-putty), and single vacuum-form (single-VF). Brackets were bonded on 25 identical stone working models. IDB trays were fabricated over working models (n  =  5 per technique) to transfer brackets to another 25 identical stone patient models. The mesiodistal (M-D), occlusogingival (O-G), and faciolingual (F-L) positions of each bracket were measured on the working and patient models using digital photography (M-D, O-G) and calipers (F-L). Paired t-tests were used to compare bracket positions between working and patient models, and analysis of variance was used to compare bracket transfer accuracy among the five techniques.Results:Between the working and patient models, double-VF had the most teeth with significant differences (n  =  6) and PVS-VF the fewest (n  =  1; P < .05). With one exception, all significant differences were ≤0.26 mm and most (65%) were ≤0.13 mm. When the techniques were compared, bracket transfer accuracy was similar for double-PVS, PVS-putty, and PVS-VF, whereas double-VF and single-VF showed significantly less accuracy in the O-G direction.Conclusions:Although overall differences in bracket position were relatively small, silicone-based trays had consistently high accuracy in transferring brackets, whereas methods that exclusively used vacuum-formed trays were less consistent.     

Comparison of the transfer accuracy of two digital indirect bonding trays for labial bracket bonding

ObjectivesTo compare the transfer accuracy of two digital transfer trays, the three-dimensional printed (3D printed) tray and the vacuum-formed tray, in the indirect bonding of labial brackets.Materials and MethodsTen digital dental models were constructed by oral scans using an optical scanning system. 3D printed trays and vacuum-formed trays were obtained through the 3Shape indirect bonding system and rapid prototyping technology (10 in each group). Then labial brackets were transferred to 3D printed models, and the models with final bracket positioning were scanned. Linear (mesiodistal, vertical, buccolingual) and angular (angulation, torque, rotation) transfer errors were measured using GOM Inspect software. The mean transfer errors and prevalence of clinically acceptable errors (linear errors of ≤0.5 mm and angular errors of ≤2°) of two digital trays were compared using the Mann-Whitney U-test and the Chi-square test, respectively.ResultsThe 3D printed tray had a lower mean mesiodistal transfer error (P < .01) and a higher prevalence of rotation error within the limit of 2° (P = .03) than did the vacuum-formed tray. Linear errors within 0.5 mm were higher than 90% for both groups, while torque errors within 2° were lowest at 50.9% and 52.9% for the 3D printed tray and vacuum-formed tray, respectively. Both groups had a directional bias toward the occlusal, mesial, and buccal.ConclusionsThe 3D printed tray generally scored better in terms of transfer accuracy than did the vacuum-formed tray. Both types of trays had better linear control than angular control of brackets.     

Transfer accuracy of vinyl polysiloxane trays for indirect bonding

Objective:To elicit the magnitude, directional bias, and frequency of bracket positioning errors caused by the transfer of brackets from a dental cast to the patient’s dentition in a clinical setting.Materials and Methods:A total of 136 brackets were evaluated. The brackets were placed on dental casts and scanned using cone beam computed tomography (CBCT) to capture 3-D positioning data. The brackets were then transferred to the patient’s dentition with an indirect bonding method using vinyl polysiloxane (VPS) trays and later scanned using CBCT to capture the final bracket positioning on the teeth. Virtual models were constructed from the two sets of scan data and digitally superimposed utilizing best-fit, surface-based registration. Individual bracket positioning differences were quantified using customized software. One-tailed t tests were used to determine whether bracket positioning was within limits of 0.5 mm in the mesiodistal, buccolingual, and vertical dimensions, and 2° for torque, tip, and rotation.Results:Individual bracket positioning differences were not statistically significant, indicating, in general, final bracket positions within the selected limits. Transfer accuracy was lowest for torque (80.15%) and highest for mesiodistal and buccolingual bracket placement (both 98.53%). There was a modest directional bias toward the buccal and gingival.Conclusion:Indirect bonding using VPS trays transfers the planned bracket position from the dental cast to the patient’s dentition with generally high positional accuracy.     

A clinical comparison of bracket bond failures in association with direct and indirect bonding

Abstract

Objective: To compare bond failure rates between direct and indirect techniques for bonding orthodontic brackets.

Design: A two-centre single blinded prospective randomized controlled clinical trial.

Materials and methods: This study was undertaken at the Birmingham Dental Hospital and Good Hope Hospital, Sutton Coldfield. Thirty-three subjects meeting the inclusion criteria were selected from orthodontic waiting lists and assigned to either of two study groups according to a split-mouth study design. The number and site of bracket failures between tooth types was recorded over 1 year. Statistical analysis was carried out using chi-square tests.

Results: Brackets were lost from 14 of the 553 teeth bonded, giving an overall bond failure rate of 2.5%. There were no significant differences in bond failures between direct and indirect bonding or in the tooth types of the failures.

Conclusions: There was no significant difference in the bond failure rates between direct and indirect bonding.     

Application of silicon hybrid transfer trays to an indirect bonding system through bracket positions referred by 3D digital software

Recently many indirect bonding systems have been developed. However, the necessary laboratory work can be quite complicated. Therefore we developed a method of systematic positioning, and a simple and easy method using a silicone tray.We measured accurate bracket positioning height (BPH-line) and referred to Kalange's method using virtual setup models. We used two characteristically different chemical bonded silicon materials as the tray as part of our indirect bonding method.We found this system to be very useful, simple to apply, and accurate.     

计算机辅助托槽定位系统的建立

目的 建立基于3D扫描、打印架构下的计算机辅助托槽定位系统(computer aided bracket placement system,CABPS).方法 通过3D扫描获取3D数字化牙颌模型,利用正畸计算机辅助设计(orthodontics computer aided design,Ortho CAD)技术对数字化模型进行牙齿分离,按照正常咬合六项标准进行牙齿排列;基于临床冠中心法和托槽槽沟平直化原则做计算机辅助托槽定位,计算机对已附带托槽定位标尺的牙齿进行原态模型复位,3D打印,压制托槽定位模板,在模拟(牙合)架上进行托槽间接粘接后模拟矫治,验证矫治效果.结果 在3D扫描、打印架构下,基于Ortho CAD技术建立了CABPS.结论 CABPS可提高托槽定位精度,实现了矫治效果可预期、可视.     

三种间接粘接方法转移托槽的准确性比较

目的:比较间接粘接技术中使用不同转移托盘转移托槽的准确性。方法:选择2019年7月至2021年1月空军军医大学口腔医院正畸科就诊的患者28例,分为A、B、C三组,分别使用3D打印托盘、双层压膜塑料托盘、双层硅橡胶托盘粘接托槽。A组口内扫描获取工作模型,使用软件定位托槽,再导出数字化模型,作为该组托槽转移前的数字化模型。B组和C组在工作石膏模型上定位托槽,使用口内扫描仪扫描,获取B组和C组托槽转移前的数字化模型。A、B、C组制作相应的转移托盘,将托槽粘接至患者口内后对患者口内扫描,获取三组托槽实际粘接的数字化模型。使用Geomagic软件测量转移前后的数字化模型,获取使用不同托盘时,托槽粘接的实际位置距离预设在近远中方向、龈 方向、颊舌方向上的线距误差,超过0.5 mm的托槽转移线距误差定义为严重误差。 结果:近远中向上B组与A组间、C组与A组间严重误差发生率的差异存在统计学意义( P<0.05)。龈 向上3组组间的严重误差发生率差异均存在统计学意义( P<0.05)。颊舌向上3组组间的严重误差发生率差异无统计学意义。 结论:(1)3D打印托盘转移托槽时严重误差的发生率显著高于双层硅橡胶托盘与双层压膜塑料托盘。(2)双层硅橡胶托盘粘接托槽时严重误差的发生率最低。     

三种间接粘接方法转移托槽的准确性比较

目的:比较间接粘接技术中使用不同转移托盘转移托槽的准确性。方法:选择2019年7月至2021年1月空军军医大学口腔医院正畸科就诊的患者28例,分为A、B、C三组,分别使用3D打印托盘、双层压膜塑料托盘、双层硅橡胶托盘粘接托槽。A组口内扫描获取工作模型,使用软件定位托槽,再导出数字化模型,作为该组托槽转移前的数字化模型。B组和C组在工作石膏模型上定位托槽,使用口内扫描仪扫描,获取B组和C组托槽转移前的数字化模型。A、B、C组制作相应的转移托盘,将托槽粘接至患者口内后对患者口内扫描,获取三组托槽实际粘接的数字化模型。使用Geomagic软件测量转移前后的数字化模型,获取使用不同托盘时,托槽粘接的实际位置距离预设在近远中方向、龈 方向、颊舌方向上的线距误差,超过0.5 mm的托槽转移线距误差定义为严重误差。 结果:近远中向上B组与A组间、C组与A组间严重误差发生率的差异存在统计学意义( P<0.05)。龈 向上3组组间的严重误差发生率差异均存在统计学意义( P<0.05)。颊舌向上3组组间的严重误差发生率差异无统计学意义。 结论:(1)3D打印托盘转移托槽时严重误差的发生率显著高于双层硅橡胶托盘与双层压膜塑料托盘。(2)双层硅橡胶托盘粘接托槽时严重误差的发生率最低。     

托槽在数字化牙颌模型上位置与间接粘结转移后实际位置的一致性研究

目的 本研究比较托槽在数字化牙颌模型上的位置与转移至初始石膏模型上的位置的差异,以期为数字化托槽间接粘结位置的一致性提供实验依据.方法 选取在含牙根的数字化牙颌模型上进行托槽定位的15个数字化模型,通过间接粘结转移托盘将托槽转移至初始石膏模型上,用OrthoRx软件工具测量每个托槽在数字化牙颌模型上的位置与初始石膏模型上位置的线距差.结果 所有牙位托槽在数字化牙颌模型上的位置与初始石膏模型上位置的线距差值均小于检验值0.20 mm,与检验值差异有统计学意义(P<0.05).结论 托槽在数字化牙颌模型上的位置与初始石膏模型上位置具有一致性.     

两种不同类型粘接剂和临床四手操作在正畸托槽粘结过程中的应用效果评价

目的：评价两种不同类型粘接剂和临床四手操作在正畸托槽粘结过程中的应用效果。方法：将正畸门诊40例需粘接托槽患者随机均分为四组,A组10例,四手操作粘接托槽184个,使用光固化粘接剂。B组10例,非四手操作粘接托槽180个,使用光固化粘接剂。C组10例,四手操作粘接托槽188个,使用化学固化粘接剂。D组10例,非四手操作粘接托槽192个,使用化学固化粘接剂。分别记录四组患者粘接托槽所需时间和1周以后托槽脱落情况,进行统计分析。结果：粘接单个托槽平均所需时间A组2．65min,B组3．52rain,C组1．95min,D组2．18min,A组与B组、C组与D组、A组与C、B组与D组分别有明显的统计学差异（P〈O．05）。1月后复诊四组的托槽脱落分别为5个、7个、4个、8个,托槽脱落率分别为：2．72％、3．89％、2．13％、4．16％,四组间没有明显的统计学差异（P〉0．05）。结论：在粘接托槽过程中,使用化学固化粘接剂和通过四手操作均可以明显缩短医生临床操作时间,并对粘接效果没有明显影响,工作效率显著提高。     

三种粘结剂在唇侧间接粘结技术中的临床应用

目的 观察比较三种粘结剂对正畸托槽间接粘结效果的影响.方法 选择需要正畸治疗患者60例,共计1200个托槽.随机分为三组,SondhiTM快速间接粘结剂组(A组)20例400个托槽、TransbondTM Supreme LV粘结剂组(B组)20例400个托槽和GC Fuji ORTHO LC粘结剂组(C组)20例400个托槽.分别采用相同方法进行托槽间接粘结,并对三组的托槽脱落率进行统计分析.结果 SondhiTM快速间接粘结剂组(A组)的脱落率为3.05％,TransbondTM Supreme LV粘结剂组(B组)脱落率为2.67％,而GC Fuji ORTHO LC粘结剂组(C组)脱落率为2.33％.三者差异无统计学意义.结论 在唇侧间接粘结技术中,应用三种粘结剂粘结托槽均可取得良好的粘结效果,但GC Fuji ORTHO LC粘结剂的脱落率最低.     

正畸托槽间接黏结技术的临床应用

目的:探索间接黏结技术在正畸临床中的应用。方法:采用糊精将托槽黏结在硬石膏模型上,然后用弹性塑胶薄膜制作转移托盘,口内托槽黏结采用化学固化或光固化方法。结果:运用该方法共黏结20位患者;观察2个月,托槽脱落率为4.6%。结论:间接黏结法由于自身的优势,可以作为直接黏结法的有力补充。     

Force and amount of resin composite paste used in direct and indirect bonding

Objective:To investigate the relationship between the forces applied by the operator and the amount of adhesive used in the direct and indirect bonding methods.Materials and Methods:A system for measuring the force applied by operator was used to test specimens prepared by 12 orthodontic specialists. To determine the proper amount of adhesive, metal brackets were bonded to transparent resin teeth using composite resin paste and different forces (100, 200, and 300 g); the area of the composite resin paste was then measured using image-analysis software. The mean forces applied in direct and indirect bonding were compared by Student''s t-test.Results:Various values for force were obtained for the direct bonding (53–940 g) and indirect bonding (150–870 g) techniques. Although in all cases the area of composite resin paste after the application of constant force was greater than the area of the metal brackets, an insufficient amount of composite resin paste on the bracket base was observed with forces of 100 and 200 g.Conclusions:A force of greater than 200 g might be preferable for obtaining a thin composite resin layer and for achieving sufficient spreading of the composite resin paste.     

计算机辅助设计制作舌侧托槽间接粘接系统的研究

目的建立计算机辅助设计制作舌侧托槽间接粘接系统,以专业工厂制作替代传统的技工室制作,从而使舌侧矫治技术在临床上得到更加广泛的应用。方法利用计算机三维重建系统形成数字化模型和托槽,利用计算机软件完成模型排牙、托槽定位、设计制作转移托盘等制作程序。结果利用本系统得到的间接转移托盘可以和实际的舌侧托槽紧密嵌合。能顺利就位于病人的原始石膏模型上。结论计算机辅助设计制作舌侧托槽间接粘接系统能简化技工室操作,缩短技工室的制作时间,提高托槽粘接精确性。     

Transfer accuracy of 3D-printed trays for indirect bonding of orthodontic brackets:: A clinical study

ObjectivesTo evaluate the transfer accuracy of 3D-printed indirect bonding trays constructed using a fully digital workflow in vivo.Materials and MethodsTwenty-three consecutive patients had their incisors, canines, and premolars bonded using fully digitally designed and 3D-printed transfer trays. Intraoral scans were taken to capture final bracket positioning on teeth after bonding. Digital models of postbonding scans were superimposed on those of corresponding virtual bracket setups, and bracket positioning differences were quantified. A total of 363 brackets were evaluated. One-tailed t-tests were used to determine whether bracket positioning differences were within the limit of 0.5 mm in mesiodistal, buccolingual, and occlusogingival dimensions, and within 2° for torque, tip, and rotation.ResultsMean bracket positioning differences were 0.10 mm, 0.10 mm, and 0.18 mm for mesiodistal, buccolingual, and occlusogingival measurements, respectively, with frequencies of bracket positioning within the 0.5-mm limit ranging from 96.4% to 100%. Mean differences were significantly within the acceptable limit for all linear dimensions. Mean differences were 2.55°, 2.01°, and 2.47° for torque, tip, and rotation, respectively, with frequencies within the 2°-limit ranging from 46.0% to 57.0%. Mean differences for all angular dimensions were outside the acceptable limit; however, this may have been due to limitations of scan data.ConclusionsIndirect bonding using 3D-printed trays transfers planned bracket position from the digital setup to the patient''s dentition with a high positional accuracy in mesiodistal, buccolingual, and occlusogingival dimensions. Questions remain regarding the transfer accuracy for torque, tip, and rotation.     

CAD/CAM转移托盘粘接托槽位置准确性研究

目的比较应用计算机辅助设计与制作(CAD/CAM)转移托盘粘接托槽的实际位置和虚拟位置的差异。方法选10例舌侧矫治的患者,在其3D整合牙颌模型上进行计算机排牙和虚拟托槽定位,然后用激光快速成型技术直接输出转移托盘,用转移托盘将托槽粘接到患者口内。用Bland and Altman's一致性分析比较托槽虚拟位置和口内实际位置测量值的差异。结果托槽虚拟位置和实际位置的线距测量差值从-0.26mm到0.19mm,转矩角度测量差值从-2.7°到2.5°,Bland and Altman's一致性分析显示托槽虚拟位置和实际位置的线距测量差值为0.01mm±0.21mm,转矩角度差值为0.5°±3.1°,所有测量项目的一致性分析显示无显著性差异。结论应用CAD/CAM转移托盘在临床上粘接托槽的位置有较高的准确性。     

Influence of the bonding interface on bracket adhesion

Adhesion strength may be explained by different theories that allow a better understanding and a better use of orthodontic adhesives. Transmission (TEM) and scanning (SEM) electron microscopy analysis of debonding areas allows to differentiate the location of bonding fractures and the consequences on enamel. Such a knowledge may be useful when choosing the most adapted protocol.     

A 15-month evaluation of bond failures of orthodontic brackets bonded with direct versus indirect bonding technique: a clinical trial

Background

The purpose of this clinical longitudinal study was to investigate the effectiveness of indirect bonding technique evaluating the number of bond failures which occurred during treatment.

Methods

Fifty-two patients were selected and divided into two groups: group A (33 patients) bonded with the direct technique and group B (19 patients) bonded with the indirect technique. The number and date of bracket failure were recorded for over 15 months. Moreover, also the effect of crowding level on bracket failures was calculated. Statistical analysis was performed by means of t-test, Kaplan-Meier survival estimates and chi-squared test.

Results

No statistically significant differences were found in the total bond failure rate between direct and indirect techniques, also when comparing the upper and lower arches. The only significant difference was found comparing the posterior segment of the lower arches, in which a higher percentage of detachments were recorded in group B, bonded with the indirect technique. Moreover, no significant differences between direct and indirect bonding were found when evaluating crowding level.

Conclusions

Orthodontic practitioners can safely use the indirect bonding technique, even in patients with severe crowding, because it does not influence the adhesive quality and the bracket survival rate.