Microleakage under adhesive systems used as sealants in primary molars

Objectives: To evaluate the sealing ability of an all-in-one adhesive system applied as pit and fissure sealant microleakage in primary molars when recovered or not by a hydrophobic layer.

Methods: Forty sound primary molars were randomly divided into 4 groups (n=10): G1 - Fluroshield (F), a sealant used as control; G2 - OptiBond (FL), a 3-step conventional adhesive system; G3 - OptiBond (AO), an one-step self-etch system; and G4 - OptiBond (AO) plus a layer of the FL' bond. All products were applied under wet condition (except F) and according to manufacturers' directions. The samples were stored in saline solution for 24h. Then, the crowns were recovered with a cosmetic nail varnish. After that, they were immersed in an aqueous silver nitrate solution (50%) for 2h, washed, and developed under fluorescent light for 8h. Each tooth was sectioned with a diamond saw and analyzed under a stereomicroscope (Laica ATC 2000), in 40x magnification, for quantifying the tracer penetration. The following scores were used: 0- no microleakage; 1- leakage in the edges; 2- leakage in the middle part; 3- leakage in the deep part of the fissures. Four scores were obtained of each tooth to compose an average value, and the data were subject to ANOVA and Tukey test (p<0.05).

Results: It was observed that F, FL and AO + FL presented similar mean values of microleakage (0.4±0.3, 0.2±0.3 and 0.4±0.3, respectively) and minors than AO (2.6±0.8).

Conclusion: It could be concluded that enamel pre-treatment have no influence in the sealing ability of the materials, but the one-step self-etch system with no bond layer was more porous than the others, and probably it could not be recommended for using as sealant.