In-vitro investigation of the mechanical friction properties of a computer-aided design and computer-aided manufacturing lingual bracket system under diverse tooth displacement condition

Abstract

ObjectiveThe purpose of this study was to compare the static (SFF) and kinetic frictional forces (KFF) of a computer-aided design and computer-aided manufacturing lingual bracket (CAD/CAM-LB) with those of conventional LB (Con-LB) and Con-LB with narrow bracket width (Con-LB-NBW) under 3 tooth displacement conditions.MethodsThe samples were divided into 9 groups according to combinations of 3 LB types (CAD/CAM-LB [Incognito], Con-LB [7th Generation, 7G], and Con-LB-NBW [STb]) with 3 displacement conditions (no displacement [control], maxillary right lateral incisor with 1-mm palatal displacement [MXLI-PD], and maxillary right canine with 1-mm gingival displacement [MXC-GD]; n = 6/group). While drawing a 0.016-inch copper or super-elastic nickel-titanium archwire with 0.5 mm/min for 5 minutes in a chamber maintained at 36.5℃, SFF and KFF were measured. The Kruskal-Wallis method with Bonferroni correction was performed.ResultsThe Incognito group demonstrated the highest SFF, followed by the 7G and STb groups ([STb-control, STb-MXLI-PD, Stb-MXC-GD] < [7G-MXC-GD, 7G-MXLI-PD, 7G-control] < [Incognito-MXLI-PD, Incognito-control, Incognito-MXC-GD]; p < 0.001). However, there were no significant differences in SFF among the 3 displacement conditions within each bracket group. Within each displacement condition, the Incognito group demonstrated the highest KFF, followed by the 7G and STb groups ([STb-control, STb-MXLI-PD] < Stb-MXC-GD < 7G-MXLI-PD < [7G-control, 7G-MXC-GD] < [7G-MXC-GD, Incognito-MXLI-PD, Incognito-control] < [Incognito-control, Incognito-MXC-GD]; p < 0.001). MXC-GD exhibited higher KFFs than MXLI-PD in the same bracket group.ConclusionsThe slot design and ligation method of the CAD/CAM-LB system should be modified to reduce SFF and KFF during the leveling/alignment stage.

Three-Dimensional Digital Superimposition of Orthodontic Bracket Position by Using a Computer-Aided Transfer Jig System: An Accuracy Analysis

“…With the aid of CAD/CAM systems, high-quality orthodontic treatment is expected to be achieved [ 29 , 30 ]. The accuracy of bracket transfer jigs has also increased as the technologies, especially CAD/CAM systems, have been developed.…”

Evaluación de los remanentes de cemento tras el descementado de brackets linguales customizados y el posterior pulido con diferentes tipos de fresas y sistemas rotatorios: un estudio in vitro

“…Posteriormente, surgieron arcos robotizados con el objetivo de facilitar al clínico la técnica lingual. Este arco también es conformado en "forma de seta" pero está doblado e individualizado mediante robótica (90). Estos arcos son producidos con CAD/CAM lo que disminuye considerablemente el error de doblado manual (59).…”

“…Este tipo de arcos son utilizados en el sistema Incognito. Su desventaja principal es la dependencia que crea al profesional del laboratorio impidiendo reaccionar de forma inmediata si el arco debe ser modificado o recambiado en caso de rotura (90).…”

“…Actualmente, se utiliza la tecnología 3D para posicionar el bracket de forma precisa sobre el LSP (89,90). Para realizar esta técnica se utilizan software informáticos que permiten colocar el arco con los brackets insertados sobre los modelos virtuales finales del paciente.…”

“…Por lo tanto, el arco recto aporta simpleza y libertad a la hora de realizar ortodoncia lingual. Además, el arco recto permite y optimiza las mecánicas basadas en el deslizamiento y la baja fricción (90).…”