Slot tolerance from three different commercial brands of brackets

Objective: The purpose of this study was to determine the quality of the size of 0.018” x 0.025” slots in brackets of three trading companies (3M, GAC and ORMCO). Methods: 120 first premolar stainless steel brackets of three trading houses were analyzed forming three groups of 40 brackets. Each bracket was observed under a Profile Projector Microscope. Three measurements were obtained for each slot: depth, internal and external height. The data were tabulated and statistically analyzed by the ANOVA test and the Student’s t test. Results: The results showed that there were statistically significant differences in depth and internal and external height between the bracket’s slot of 3 different companies (p < 0.05). The companies 3M and GAC fulfilled the manufacturer’s specifications (p < 0.05). In terms of internal height, GAC complied with the manufacturer’s specifications (p < 0.05). In relation to external height, ORMCO complied with what is specified by the manufacturer (p < 0.05). Key words: Slot tolerance, slot depth, internal height of the slot, external height of the slot