Methods: PS was applied per manufacturers' instructions using three different commonly used dental material applicators on 90 prepared caries-free extracted human teeth (30 per group). The applicators included an American Orthodontics micro-brush (MB), a Centrix bristle brush (BB), and a Centrix sponge-tip applicator (ST). All teeth were photographed at a standardized distance, and a bubble count in a standardized area of the enamel surface (25mm2) was performed twice for each group using Pro Plus software. The intra-class correlation coefficient was 0.99 (p<0.0001) indicating strong agreement between duplicate measurements made by a single observer. Groups were compared with ANOVA model to the ranked data and the Bonferroni test. An alpha of 0.05 was chosen.
Results: The data provided evidence that there was a significant effect for method of application of PS on the presence of bubbles in the sealant (p<0.0001) using ANOVA. The Bonferroni test revealed that teeth in the BB group had a significantly lower mean number of small air bubbles (3.58 ± 3.02) than the MB (41.70 ± 24.51) and ST (42.07 ± 28.74) groups (p<0.0001). There was no significant difference between the MB and ST groups.
Conclusion: To reduce bubble incorporation into PS, the standard bristle brush should be used rather than the micro-brush or sponge-tip applicator.
Study supported by a University of Iowa College of Dentistry Dows Research Award.