The aim of this study was to evaluate the acid neutralizing capacity and to observe surface changes of giomer in comparison with composite resin, when it comes in contact with an acidic solution.
A packable giomer(Beautifil II) and a flowable giomer(Beautifil Flow F02) were used as experimental groups,while a packable composite resin(FiltekTM Z-250) was used as control group. pH values were measured after mixing the specimens of the disc and powder types with a pH 2.0 hydrochloric acid solution, respectively. Also,in the case of powder type giomers used in the earlier experiment, their pH values were measured again after mixing them with a fresh acid solution. Moreover, surface structure changes of disc type specimens were observed by using a scanning electron microscopy(SEM).
In the disc type test, the pH values of packable giomer were significantly increased after 24 hours(p < 0.05).
In contrast, in the powder type test, the pH values of packable and flowable giomers were dramatically increased within 30 minutes. The pH value of packable giomer, in particular, was higer than that of flowable giomer(p < 0.05). In the repeated neutralizing test, the degree of pH variation was lower than that of the previous neutralizing test(p < 0.05). Erosive changes on the surface of packable giomer were observed to be more than those on composite resin and flowable giomer as well.
In conclusion, giomer has a acid neutralizing capacity, when it comes in contact with an acidic solution.
Especially, packable giomer with high filler content has a greater acid neutralizing capacity than flowable giomer.