ACCURACY OF SLOT DIMENSION WITHIN SETS OF ORTHODONTIC BUCCAL TUBES

Terry Auditorium

Objective. Objective: This study aims to evaluate the dimensional precision of orthodontic buccal tubes slots from different orthodontic companies using the Scanning Electron Microscope (SEM). Background. Orthodontic appliances have evolved significantly over the past century from Angle's E-arch to CAD-CAM manufactured customized brackets. The original Edge-wise Appliance was introduced by Angle in 1928 after several years of experimentation.1 Angle chose the dimension of 0.022x0.028 inches as the optimal size for orthodontic bracket slot to ensure proper distribution of forces ¬¬¬to dentition. Since Angle emphasized maintaining a full of complement of teeth, achievement of ideal occlusion depended on ensuring “ideal” position of each tooth within the dental arch. Mastering the skills of wire bending was essential in the practice of orthodontics at the time. First-order or in and out bends compensated for variations in labio-lingual contour and thickness of teeth to achieve proper alignment of dentition. Second-order bends (tip) ensured root parallelism and third-order (torque) bends placed teeth in their proper facio-lingual inclination. Methods. Four of the most popular orthodontic companies within the US who manufacture and distribute molar tubes to orthodontists were selected for this study including Opal (Ultradent), Ormco(Damon), American Orthodontics and 3M Unitek. Each company was asked to send 20 molar tubes, 022 slot (.0225 x .0285 inches), which have been manufactured within the past 2 months to be used in this study. We measured the accuracy of individual tube dimensions in relation to their respective company catalogs, as well as document any defects observed within these tubes. Descriptive statistics, means and standard deviations were calculated for all buccal tubes from the four companies and for each wall of the respective tubes. Results. : All four companies produced slots that were on average over-sized. There was no consistency in meeting the standards of dimensions when comparing each of the four walls for each company. However, a higher percentage of American orthodontics and 3M tubes met the standards of measurement of the occlusal and gingival walls. All tubes were convergent from mesial to distal and lingual to buccal direction. Conclusion. All companies manufactured oversized tubes.There was no consistency in dimensional accuracy of tubes produced by any of the four companies. All tubes were convergent from mesial to distal and lingual to buccal dimension. Grants. HPD