Effect of Prophylactic Agents on the Surface and Structural Properties of Brackets and Archwires: An In Vitro Study

Frictional resistance at the bracket–archwire interface plays a critical role in orthodontic sliding mechanics and overall treatment efficiency. Prophylactic mouthrinses prescribed during orthodontic treatment may alter the surface characteristics of orthodontic materials, thereby influencing frictional resistance. A total of 120 stainless-steel bracket–archwire assemblies were divided into four groups based on immersion media as Fluoride mouthrinse, Chlorhexidine mouthrinse, Essential oil mouthrinse and Artificial saliva. Each group was further subdivided according to ligation method using elastomeric modules and stainless-steel ligatures. Samples were immersed for 120 minutes at 37°C. Frictional resistance was evaluated using a universal testing machine at a crosshead speed of 1 mm/min. Surface morphology was assessed using scanning electron microscopy (SEM). Statistical analysis was performed using one-way ANOVA and post hoc tests (p<0.05). No statistically significant difference in frictional resistance was observed among elastomeric module groups (p>0.05). In contrast, stainless-steel ligature groups demonstrated statistically significant differences (p<0.05), with the essential oil mouthrinse group exhibiting the highest frictional resistance. Overall, frictional resistance was significantly greater with stainless-steel ligatures compared to elastomeric modules. SEM analysis revealed maximum surface deterioration, pitting corrosion, and irregularities in the essential oil group, whereas chlorhexidine and artificial saliva groups exhibited comparatively smoother surface morphology. Essential oil mouthrinse significantly increased frictional resistance and surface deterioration, particularly with stainless-steel ligatures. Chlorhexidine demonstrated minimal adverse effects on orthodontic materials. The method of ligation plays a major role in determining frictional resistance during orthodontic sliding mechanics.