Method: 5 groups of extracted teeth (6 maxillary molars and 4 mandibular molars per group) were randomly sorted and cleaned. A 0.5-1mm fissure was made in each sample, followed by etching (30s), cleaning, and drying. Sealants were applied according to manufacturer's instructions. The samples were light cured 40s and checked with an explorer. The unsealed surface of the sample was coated with a nail-polish and thermocycled 5°C-55°C for 2,000 cycles. The specimens were stained in 2% basic fuchsin for 24hrs, rinsed, air dried,and embedded in epoxy-resin. Each specimen was then sectioned mesiodistally into 6 slabs (1.2 mm-thick, 5-7 surfaces), observed and photographed under a microscope at 40x magnification. The microleakage degrees were scored on a scale of 0 to 4 (0=no penetration, 1=1/4 penetration, 2=1/2 penetration, 3=3/4 penetration, 4=penetration into the bottom of the fissure). The data was analyzed using the Kruskal-Wallis test with Tukey’s Honestly Signficant Differences test performed on the ranks for post-hoc analysis.
Result: The Kruskal-Wallis test revealed a significant difference (Χ2=21.0, df=4, p<0.001) between scores for different sealants. The mean scores and standard deviations were: EXP-2 (0.69±0.58), EXP-1 (1.48±0.64), CL (2.19±1.06), E34 (2.49±0.96), and FS (2.62±1.03). EXP-2 and EXP-1 had significantly lower scores and smaller standard deviation than other groups (p<0.01).
Conclusion: Both the EXP-1 and EXP-2 sealants showed little to no leakage compared to commercial sealants. Therefore, they are expected to have excellent retention. Supported by NIH/NIDCR grant 5R01DE019203-03.
Keywords: Adhesion, Dental materials, Sealants and Sealants