Differences in Enamel Surface Roughness Changes after Debonding Using Resin Infiltration System and Nano-Filled Resin Coating

摘要

Debonding and removal of adhesive remnants after orthodontic treatment will increase the surface roughness of enamel, This condition promotes plaque accumulation which leads to enamel demineralization. Analyzing enamel surface roughness changes after debonding using resin infiltration system, nano-filled resin coating, and the combination of both materials. We also analyze the differences in surface roughness changes of enamel between the three groups. 30 extracted upper first premolar tooth specimens were bonded with standard edgewise bracket and stored in distilled-water for 24 hours. Then, brackets were debonded and adhesive remnants were removed using highspeed dome tapered tungsten carbide bur at 30.000rpm. Afterwards, each specimen was randomly assigned into one of the three treatment groups (n=10), which were: resin infiltration system (R); nano-filled resin coating (N); A combination of resin infiltration system + nano-filled resin coating (RN). The surface roughness of enamel was measured using Mitutoyo SJ-301 Surface Roughness Tester before and after the treatment. Enamel surface roughness were significantly changed in all three groups after the treatment (p<0.05). Enamel surface roughness of R group decreases from 0.424 μm to 0.277 μm while N group decreases from 0.421 μm to 0.202 μm, and RN group decreases from 0.419 μm to 0.162 μm. The differences in surface roughness changes between three groups were also significant (p<0.05). The biggest differences found in RN group (0.257 μm) resulting the smoothest surface, followed by N group (0.218 μm) and R group (0.147 μm) respectively. A combination of resin infiltration system and nano-filled resin coating reduced the surface roughness of enamel after debonding significantly compared to resin infiltration system or nano-filled resin coating alone.