Evaluating the mechanical and physical properties of various glass ionomer based restorative materials In Vitro

The aim of this in vitro study was to evaluate the mechanical and physical properties of different types of glass ionomer based restorative materials in vitro. In the study, 90 discs with restorative materials prepared in Teflon molds and 72 caries-free bovine teeth were used. Thirty of the ninety samples prepared in 10 mm-diameter, 2 mm-thick teflon molds for the purpose of evaluating the micro-hardness of restorative materials were used with Beautiful Bulk Restorative, thirty of them using EQUIA Forte HT and thirty of them using Fuji II LC. The samples from each group were divided into two groups for hardness evaluation before and after thermal cycling. Vickers hardness values were measured before and after 10000 cycles of thermocycling at 5-55°C. For the microleakage study, class V cavities were prepared with an aerator-micromotor on the buccal surfaces of 72 randomly selected bovine teeth. After an equal number of groups were formed, Beautifil Bulk Restorative, EQUIA Forte HT, Fuji II LC were applied to the prepared cavities according to the manufacturer's recommendations. Twelve samples in each material group were kept in a 0.5% basic fuchsin solution for 24 hours and the degree of dye penetration was examined with a stereomicroscope. Two layers of dark nail polish were applied to the cavity borders at a distance of 1.5 mm and kept in 0.5% basic fuchsin solution for 24 hours. In the microhardness evaluation, a statistically significant difference was observed between the Vickers hardness values of Beautifil Bulk Restorative, EQUIA Forte HT and Fuji II LC discs before and after thermal cycling (p<0.05). The results of the mechanical tests performed in this study suggest that Beautifil Bulk Restorative material may be preferred for the restoration of young permanent teeth in pediatric dentistry. Taking into account the physiological wear in deciduous teeth, it can be said that EQUIA Forte HT restorative material can be preferred in deciduous tooth restorations, as materials with lower microhardness values have higher wear.