MICROLEAKAGE OF A UNIVERSAL ADHESIVE USED AS A FISSURE SEALANT

Purpose: To evaluate the microleakage of a universal hydrophilic adhes ive (OptiBond dual-cure) by itself as a pit and fissure sealant compar ed to that of an ionomeric product (VariGlass) and two hydrophobic sea lants (Delton and Fluroshield). Materials and Methods: Sixty-four extr acted human third molars were sealed with one of these four materials under either a conventional procedure (free of humidity) or after cont amination of the etched surfaces with 3 mu l of human plasma. The seal ed teeth were subjected to 1,500 thermocycles (1 min/5-55 degrees C) a nd to 450,000 mechanical cycles under an 8.5 kgf average load at 37 de grees C. The tooth crowns were partially coated with nail varnish, imm ersed in a 50% aqueous solution of AgNO3 for 2 h in darkness, washed a nd then developed for 8 h under fluorescent light. The teeth were sect ioned and dye penetration was scored according to a 4-point scale by f our trained professionals. Results: An ANOVA suggested that under no h umidity conditions, the average score for VariGlass (1.92 +/- 0.36) wa s significantly higher (P=0.0006) than that corresponding to the three remaining materials (1.28 +/- 0.20) which were considered equivalent. Under humid (plasma contaminated) conditions, there was complete loss of Delton and Fluroshield in all cases, whereas the average score for VariGlass (1.98 +/- 0.36) was slightly higher (P=0.0444) than that fo r OptiBond (1.62 +/- 0.36). These results suggest that OptiBond may be used by itself as a pit and fissure sealant instead of the combinatio n of adhesive plus sealant.