Effect of fermented milk product on composite resin surface / 대한구강보건학회지

ABSTRACT

Objectives@#The present study was carried out to identify the effects of commercially available fermented milk on the surfaces of composite resins. @*Methods@#The experiment included 6 groups Fermented milk (Group 3), fermented milk supplemented with 3% calcium (Group 4), specimens coated with fluoride and then treated with fermented milk (Group 5), specimens coated with fluoride and then treated with fermented milk supplemented with calcium (Group 6), mineral water (Group 1), and carbonated beverage (Group 2). The prepared specimens were immersed in the experimental solution to analyze the effects of the test fluid on the surfaces of the composite resin specimens. The degree of microhardness on each specimen surface was subsequently measured. The results were obtained using scanning electron microscopy. @*Results@#The pH values of the experimental solutions in an increasing order were Group 2 (2.34 ±0.08), Group 3 and Group 5 (3.45±0.03), Group 4 and Group 6 (4.04±0.06), and Group 1 (7.72 ±0.17). Significant differences in the Vickers hardness number (△VHN) were found between the groups when measured before and after immersion in the experimental solution in the following order -11.48±1.45 (Group 2), -9.54±1.15 (Group 3), -9.21±1.21 (Group 4), -8.14±0.84 (Group 6), -8.10±0.92 (Group 5), and -1.71±0.57 (Group 1) (P<0.05). Scanning electron microscopy findings of the composite resin surfaces in Groups 5 and 6 revealed smooth surfaces similar to those in Group 1 ( negative control). In contrast, Groups 3 and 4 showed rough surfaces with severe cracks between the crystals, similar to those of Group 2 (positive control). @*Conclusions@#The intake of fermented milk may attenuate the surface microhardness of composite resins. To slow down the reduction in microhardness following fermented milk consumption, coating the composite resin surfaces with fluoride and adding calcium supplement to the fermented milk could be considered.