Effect of Primer Application on the Lingual Retainer

Background: The aim of this study was to examine the effect of self-etch primer (SEP) application on the bond failure rate of a mandibular bonded lingual retainer over 24 months.

Materials and Methods: After the removal of the orthodontic appliances, the lingual retainers, which were made of six-stranded stainless steel wire 0.0215 inches in diameter, wiil bent and bond onto the lingual surface of all mandibular anterior teeth. The study will performed using a split-mouth design. In the study group, the SEP will be administired to the teeth's lingual surfaces. In the control group, they will etch using 37% phosphoric etchant liquid gel. After etching, the primer wiil be applied. The adhesive resin was applied and the lingual retainer was fitted. The patients will be re-valuated over 24 months. The first bond failures and the amount of adhesive remaining on the tooth will be recorded as the adhesive remnant index (ARI) scores.

The chi-square test will be used to compare the bond failure rates and ARI scores between the groups. The survival rates of the retainers will be estimated using the Kaplan-Meier test. The significance level will P < 0.05.