Evaluation of the influence of surface treatment of artificial tooth on the adhesive bond strength to a commercially available denture base resin-in vitro

Purpose: Purpose of the study is to evaluate the effect of pre-processing treatment of ridge-lap surfaces of acrylic teeth, air abrasion, chemical modification or combination of both on the strength of the bond between the teeth and the denture base resin.. Materials and method: Total of 32 tooth-acrylic resin samples were equally divided into four groups consisting of eight samples each.. The ridge-lap surfaces of each tooth was flattened to the designated level with a tungsten carbide acrylic bur and finished and polished. Ridge lap area of each group was subjected to pre-processing surface treatment like No treatment, air abrasion, chemical application and combination of both respectively. Wax cylindrical specimen of 20 mm X 17 mm dimensions were obtained using PVC pipes. Acrylic teeth were placed on the wax cylindrical specimens and acrylized. All samples were subjected to bond strength evaluation. Shear load testing was carried out in the Universal testing machine. The failure surfaces were subsequently examined under a stereomicroscope. Results: Obtained data was subjected to statistical analysis. The ultimate shear strength value obtained amongst all the test groups was the highest (89.18 Kgf) for Group IV, thereby indicating the effect of combination of air-abrasion and MMA conditioning. Although the highest shear bond strength value seen in Group II (69.56 Kgf) was similar to Group III (69.29 Kgf), yet it was higher than highest value seen in Group I (54.65 Kgf)., Conclusion: There was a significant effect produced on the shear bond strength of the interface when both MMA application and air-abrasion of the ridge-lap surfaces was carried out. When done singly, these modalities showed numerically higher bond strength values but these values were not statistically significant in comparison to the control group in which no treatment was carried out.