Microtensile adhesion of sealants to intact enamel.

UNLABELLED: Contamination of etched enamel with saliva has been shown to result in sealant failure. Hydrophilic adhesives improve retention of sealants when enamel is contaminated. OBJECTIVE: The objective of the present study was to characterize the adhesion of two sealants to unprepared enamel etched with phosphoric acid or conditioned with the all-in-one, self-etch adhesive Adper Prompt L-Pop. METHODS: The two proximal enamel surfaces of 16 sound molars were assigned to four conditioning regimens: (1) 35% phosphoric acid for 15 s; (2) Adper Prompt L-Pop, one layer light-cured prior to sealant placement; (3) Adper Prompt L-Pop, two layers light-cured prior to sealant placement; and (4) Adper Prompt L-Pop, one layer co-cured with sealant. One of two sealants, i.e. Clinpro or Delton DDS, was applied, light-cured, followed by a composite build-up to provide support for microtensile bond testing. RESULTS: The highest mean bond strengths were obtained when Adper Prompt L-Pop was applied in two layers and light-cured prior to the insertion of Clinpro Sealant. Co-cure of Adper Prompt L-Pop with either sealant resulted in bond strengths which were not significantly different from those of the phosphoric acid control. The use of Adper Prompt L-Pop in one layer cured prior to sealant placement resulted in statistically lower bond strengths than any other application technique regardless of the sealant used. Clinpro Sealant resulted in statistically higher bond strengths than Delton DDS Sealant. CONCLUSIONS: Application of one layer of Adper Prompt L-Pop co-cured with the sealant resulted in bond strengths similar to those obtained with phosphoric acid etching.

Microleakage of three generically different fluoride-releasing liner/bases.

Three generically different fluoride-releasing materials that function as a liner or base were assessed for their microleakage performance on enamel and dentine. Group 1 (light-cured liner/base) showed much more leakage, but less bulk absorption of tracer, than Group 2 (traditional glass ionomer) or Group 3 (light-cured glass ionomer). The response of the three materials to tracer penetration was consistent with what is known about their chemistry. The Group 2 and 3 materials are probably the materials of choice at the caries-vulnerable margins, which are not easily visible for inspection.