Friction between different wire bracket combinations in artificial saliva: an in vitro evaluation

Abstract

ObjectiveThe objective this work was to assess the friction coefficient between brackets and wires of different materials under conditions simulating the oral environment.Material and MethodsStainless steel (SS) and titanium-molybdenum alloy (TMA) wires of 0.019x0.025-in diameter (American Orthodontics) and polycarbonate bracket (American Orthodontics), ceramic bracket (American Orthodontics), and metal bracket (3M Unitek) with slots of 0.022x0.030-in were used. The friction coefficient was assessed by means of mechanical traction with the system immersed in artificial saliva. The mean roughness of both wire surface and bracket slots was evaluated by using a surface profilometer.ResultsThe system using TMA wire and polycarbonate bracket had the highest roughness (p<0.05). SS wire with ceramic bracket had the highest friction coefficient, whereas the use of metallic bracket yielded the lowest (p<0.05). However, it was observed a statistically significant difference in the system using TMA wire and ceramic bracket compared to that using TMA wire and polycarbonate bracket (p=0.038).ConclusionCeramic brackets in association with SS wire should be judiciously used, since this system showed a high friction coefficient.

Stainless Steel: Material Facts for the Orthodontic Practitioner

“…Friction is defined as the force opposing the movement of two objects in direct contact to each other and its direction is tangent to a common interface between both surfaces [76]. This concept must be kept in mind in orthodontics since it has an influence on the rate of tooth movement [77].…”

“…This concept must be kept in mind in orthodontics since it has an influence on the rate of tooth movement [77]. Friction is influenced by many factors, including, but not limited to, the type of bracket and wire materials [76,78]. Researchers have found that the combination between stainless steel wires and brackets display the lowest friction coefficients among regular materials used to manufacture brackets and wires [75,76,78], while the combination between beta-titanium wire and stainless steel bracket showed much higher levels of friction [78].…”

“…Friction is influenced by many factors, including, but not limited to, the type of bracket and wire materials [76,78]. Researchers have found that the combination between stainless steel wires and brackets display the lowest friction coefficients among regular materials used to manufacture brackets and wires [75,76,78], while the combination between beta-titanium wire and stainless steel bracket showed much higher levels of friction [78]. This topic is important to orthodontists because a phenomenon known as cold welding (the result of adhesion between both materials) may have implications in the length of orthodontic treatment [79].…”

Static and kinetic friction force and surface roughness of different archwirebracket sliding contacts

“…Studying friction between wire and bracket in artificial saliva, Fidalgo et al 8) found that the combination between ceramic brackets and stainless steel wire showed a high friction coefficient when compared with the combination of stainless steel wire against polymer (polycarbonate) bracket.…”

The Effect of Fluoride on Beta-Titanium Orthodontic Wire's Surface Texture and Friction Resistance

“…However, the various agents used for maintaining good oral hygiene during orthodontic treatment may affect the physical properties of titanium wires, and thus may increase the frictional forces between ceramic brackets and titanium wires. Consequently, this may affect the outcome of orthodontic treatment [1][2][3][4].…”