Microleakage of three conventional glass ionomers using 45Ca and methylene blue

This study sought to compare the sealing ability of two conventional ionomers and a new intermediate/provisional ionomer formulation using sequential applications of two different tracer methodologies. Thirty freshly extracted (< 6 months) human third molars, stored in 0.1% sodium azide solution, were divided randomly into three experimental groups for preparation of simulated Class V caries at the cementoenamel junction of the facial surfaces. Three materials were used to restore the cavity preparations. After restoration, the teeth were thermocycled for 100 cycles (between 4.0 degrees C and 58 degrees C). To evaluate the microleakage of the materials and compare the tracer's ability to measure microleakage, the teeth were subjected to 45Ca and methylene blue. Treated teeth were bisected longitudinally through the restoration, then each sectioned tooth half was scored by three independent evaluators using a 0 to 4 scale, depending on the tracer penetration. The results showed that all of the materials investigated performed well and no statistical differences were found among the materials, the tracer used, or the margin evaluated.