Friction Between Metallic Brackets Before and After Clinical Use: A Comparative Study

Abstract

The friction is a factor that can result on changes in efficacy of sliding orthodontic mechanics. Different factors can impact on the friction force: the composition and properties of orthodontic wires and brackets, the cleaning of orthodontic braces, and even saliva. This study aimed to evaluate the friction in two brands before and after use in the oral environment. Ten patients from the orthopedic clinic of the Master’s of Dentistry, with two premolars bonded of each patient. The patients were divided, according with total number of brackets (n= 40): 2 control groups - without exposure to the buccal medium - (G1 and G2) and 2 experimental groups - with exposure to the buccal medium - (G3 and G4). The brackets were testes on a friction machine and evaluated in a two-way ANOVA test. It was observed that the brand used in groups G2 and G4 presented greater friction with the orthodontic wire and the G2 group brackets presented similar frictional force to G3, which had already been exposed to clinical use. Brazilian brackets brands presented an increased friction after clinical use.