In vitro assessment of surface roughness and microbial colonization on nickel titanium wires obtained from different manufacturers

Nickel-titanium wires and Copper nickel-titanium wires obtained from three different manufacturers. They were divided into three groups: Group 1 - GAC (Sentalloy®), Group 2 - ORMCO^TM, and Group 3 - American Orthodontics (AO)®. Further, they were tested for surface roughness using a Profile projector. <i>Streptococcus mutans</i> adhesion on wires was tested by inoculating the wires in a saliva sample after isolating the bacteria by overnight incubation of the sample in blood agar. Surface roughness and bacterial adhesion were significantly greater in copper nickel titanium wires of all the three companies; rectangular wires show greater surface roughness and adhesion than round wires. Thus, increase surface roughness of orthodontic wires lead to increased bacterial colonization, affecting their biocompatibility.