Three-year evaluation of sealant: effect of isolation on efficacy.

This study analyzes the clinical effectiveness of a sealant (Delton) and its requirements for retreatment to maintain the optimum protection from pit and fissure caries. One hundred paired occlusal surfaces were treated in 29 patients. Two contralateral, partially erupted, noncarious molars with deep occlusal fissures were randomly selected to receive a sealant; one had a rubber dam and the other, cotton rolls for isolation. Each tooth received a prophylaxis with a rubber cup and a pumice slurry. The dryness of the field was evaluated. Each tooth was etched with 37% phosphoric acid for 60 seconds, rinsed for 15 seconds, and dried for 30 seconds. Sealant (Delton Tinted) was applied with a syringe according to manufacturer's instructions. Sealants were evaluated and reapplied where indicated at 6-month intervals. The average 6-month retention rate over 36 months was 95%, regardless of the method of isolation used when the sealant was applied initially. No tooth under treatment with a sealant became carious. The retreatment rate was highest at baseline (8%) and at 6 months (11.3%). Of the total number of retreated sealants, 61% were from the mandibular arch. During the 36 months of this study, 31% of the treated teeth required at least one retreatment.