Preventive effect of two glass-ionomer cements vs. two compomer materials

Methods: Standardized 40 class V cavities were prepared on buccal and lingual surface of 20 extracted caries free premolars with one half in enamel and one half in cement. Ten cavities of each group were restored with glass ionomer cements Fuji IX (GC), Ketac Molar Aplicap (3MEspe), and compomer materials Dyract (Dentsply) and Compoglass (Vivadent) according to manufacturer's instructions. Teeth were thermocycled for 1800 cycles between 5-55°C with dwelling time of 10 s. After thermocycling teeth were immersed in demineralizing solution (pH 4, 95) for 4 weeks. After that time teeth were rinsed, enrobed in epoxy resin (Citofix Kit, Struers) and sectioned in 2-3 sections that were evaluated under polarized microscope (100x magnification, Opton) and photographed (Camedia, Olympus). Wall demineralization was measured on enamel and cement tissue in contact with restorative materials applying Olympus DP soft, Version 3, 2. Statistical analysis was performed using one factor ANOVA and Tukey HSD test.

Results: Lowest level of demineralization on enamel tissue showed Ketac Molar Aplicap (707µm). In the cement area the lowest level of demineralization was observed for Ketac Molar Aplicap (734µm), and Fuji IX (732µm). There was significant difference between Fuji IX and Compoglass on cement tissue (p=0, 0138), and between Ketac Molar Aplicap and Compoglass (p=0,022) on cement tissue.

Conclusion: Hard dental tissues show lowest level of demineralization in contact with glass ionomer restorations. Results also show that good marginal adaptation is equally important as preventive properties of the material. Further laboratory evaluations are required to confirm our preliminary results.