Effect of cast Co-Cr and acetal resin removable clasp on the surface of enamel

Abstract

Objective: Objetive of the study was to evaluate the effect of cast Co-Cr and acetal resin clasp on the surface of tooth. Methodology: Ten extracted human mandibular molars were selected for the study. Clasp holding surfaces of the teeth were demarcated and examined by stereomicroscope and optical profilometer to evaluate the surface roughness qualitatively and quantitatively. The molars were then mounted on a cast and on which cast Co-Cr and acetal resin clasps were fabricated with an attached vertical strut. The assembly was placed on a masticatory simulator. Three thousand cycles of insertion and removal were carried out to simulate 2 years of usage. After the experiment was completed, the molars were evaluated for the surface changes by stereomicroscope and optical profilometer. Results: Qualitative analysis by stereomicroscope showed linear scratches and grooves on the surface of enamel caused by the use of cast Co-Cr and acetal resin clasp. Minimal scratches were seen on the enamel when acetal resin clasp was used. Optical profilometry showed statistically significant results (P < 0.0001) with the Co-Cr clasp. Acetal resin clasps showed insignificant results. The retentive force of cast Co-Cr clasp showed a decrease from 12.4 N to 8.1 N. Whereas, the retentive force of acetal resin clasp reduced from 5.2 N to 4.03 N at the completion of the experiment. Conclusions: Acetal resin clasps do not abrade the surface of tooth and maintain retention. Acetal resin clasps are esthetic and are available in 16 different shades.