The purpose of this study was to investigate the effect of cavity configurations on the marginal leakage of class 5 glass ionomer cement and composite resin restorations.
Four types of cavities such as saucer shape, notch shape, combined shape(notch shape occlusally and saucer shape gingivally), and U-shape were prepared on the buccal and lingual surfaces of 80 extracted premolars(40 cavities for each shape). Occlusal cavity margins were placed at enamel and cervical margins were placed at dentin. 10 cavities of each shape were restored with Ketac-Fil as a conventional glass ionomer cement, Fuji Ⅱ LC improved as a resin-modified glass ionomer cement. Z-100 as a hybrid composite resin, and Tetric Flow as a flowable composite resin(40 cavities for each material). After thermocycling, teeth were immersed in 5% basic fuchsin solution for 6 hours and sectioned longitudinally in a buccolingual direction through the center of the restoration. The dye penetrations at the tooth-restoration interface were examined by stereomicroscope.
The Result were as follows
1. In saucer shape, notch shape and combined shape, composite resin restorations showed lesser leakage than glass ionomer restorations (p<0.05) and in U-shape, Tetric Flow showed the least marginal leak-age and others were decreased as Z-100, Fuji Ⅱ LC improved, Ketac-Fil in that order. There were statistically significant difference between Tetric Flow and Fuji Ⅱ LC improved, Ketac-Fil and between Z-100 and Ketac-Fil(p<0.05).
2. In Ketac-Fil restoration group, saucer shape showed the highest marginal leakage and U-shape showed the least marginal leakage and others were decreased as notch shape, combined shape in that order. There were statistically significant difference between saucer shape and combined shape, U-shape and between notch shape and U-shape(p(0.05).
3. In Fuji Ⅱ LC improved restoration group, U-shape showed the least marginal leakage. There were statistically significant difference between U-shape and other three shapes(p<0.05).
4. The cavity configuration had no significant effect on marginal leakage of composite resin restorations (p>0.05).
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