Investigation of the effects of composite, attachment and aligner type, tooth inclinations, crowding and pressurized application of the template on the construction of clear aligner attachments

OBJECTIVE: Our study aims to investigate the effects of composite and attachment type, tooth inclinations, crowding amount and pressurized application of the template on the accuracy of clear aligner attachments. MATERIAL AND METHOD: In our study, 2 different phantom jaws were created from 48 extracted teeth and 3-dimensional (3D) scans were taken from these jaws with 3Shape TRIOS #C4.1. In accordance with these scans, templates containing traditional attachments from Orthero, FAS aligner system and Smilab were requested. For one of the phantom jaws, 3 sets of templates were taken from each company. Attachments were placed on the phantom jaws via templates in two different ways: with and without applying pressure during the process. These procedures were repeated using templates with 3 different composite materials with different viscosities (3M™ Filtek™ Supreme Flowable Restorative Syringe, AO Bracepaste Medium Viscosity Adhesive, Tokuyama Dental Estelite Sigma Quick Supra-Nano Filled Universal Composite). After the attachment application from the phantom jaws, 3D scans were taken again via 3Shape TRIOS #C4.1 and the scans obtained before and after the application were overlapped on the Geomagic Control X Software program. Dimensional measurements were made on these overlaps and the effects of composites, attachment types, crowding amounts, tooth inclinations and applying pressure to the template on the accuracy of the attachments were analyzed. For the analysis of statistical data, parametric tests were used to evaluate normally distributed quantitative data, and non-parametric tests were used in cases that did not show normal distribution. Under the assumption of normality, in case of Quantitative-Quantitative, Pearson Correlation, in case of Qualitative-Quantitative, Independent Sample t test and One Way Anova tests were used according to the number of groups. In cases where normality was not achieved, Spearman's Correlation was used in the case of Quantitative-Quantitative, and Mann-Whitney U test and Kruskall Wallis tests were used according to the number of groups in the case of Qualitative-Quantitative. If the data type was qualitative, the Chi-Square test was used. Significance was evaluated at p<0.05 and p<0.01 levels. RESULTS: When low viscosity composite is used, the amount of overflowed composite is less in teeth with ideal inclination than in procline and retrocline teeth. If no pressure was applied to the template during curing, the amount of overflowed composite was higher than when pressure was applied. When evaluated according to the amount of crowding, the amount of overflowed composite is less in the area with crowding, while the size of the attachment is more. When a thicker template is used, adaptation is better and the amount of overflowing composite is less. If pressure is applied to the template during curing, the amount of overflow composite is less when using high viscosity composite, while the amount of overflow composite is more when using high viscosity composite when no pressure is applied to the template. CONCLUSION: As a result of the study, it was found that composite and aligner type, tooth inclinations, application of pressure to the template and the amount of crowding have an effect on the attachment construction. It is thought that it is useful to consider these effects in the construction of attachments, which are of great importance in obtaining the desired tooth movements in clear aligner treatments. Keywords: Attachment, Composite, Crowding, Pressure, Plate, Inclination