The effect of orthodontic adhesive and bracket-base design in adhesive remnant index on enamel

BackgroundThe purpose of this study was to identify the effects of bracket-base design and adhesive on adhesive remnant index (ARI) and enamel surface area covered by adhesive.MethodsThe sample consisted of 32 recently extracted premolars. The teeth were randomly assigned to one of four groups: conventional mesh base and composite resin; laser-etched base and composite resin; conventional mesh base and resin-modified glass ionomer; and laser-etched base and resin-modified glass ionomer. After a week, all brackets were debonded. The debonded bracket-base surface and the buccal surface of each tooth were studied under the microscope, and the remaining adhesive was scored using the ARI. The extent of coverage of the tooth by adhesive remnants was also calculated, outlining the different areas of adhesive.ResultsA Fisher's exact test indicated significant differences between the groups. The adhesive resin group showed the highest ARI scores independent of the bracket-base design, whereas between the two bracket-base designs, the laser-etched bracket design showed higher ARI. ARI scores reliably depict the extent of enamel covered by adhesive compared with the measurement of the actual area covered.ConclusionVarying the bracket base and adhesive may result in different ARI scores, which can affect the enamel surface during debonding.