Gastroözofageal Reflü Hastalığı (GÖRH) taklit edilmiş ortamda ortodontik retainerlardaki mikrosızıntının incelenmesi – in-vitro çalışma

The aim of this study is to evaluate the microleakage on two different orthodontic retainers under simulated gastroesophageal reflux disease. While bonding the retainers, the impact of two different bonding materials with the effect of the previous air abrasion of the enamel to the microleakage will also be observed. 144 extracted bovine incisors were divided randomly into sixteen groups, each group containing 9 samples. Eight of these groups were preconditioned with air abrasion. Two different adhesives ( 37% phosphoric acid + 3M Transbond XT primer + 3M Transbond LR adhesive and 37% phosphoric acid + Transbond XT primer + 3M Flowable Composite ) were used to bond two different types of retainers ( braided retainer wire of .10×.028-inch 6" length and ss multi-strand wire with co-ax straight length 0215 14"). Elipar S10 curing light was used to polymerize these adhesives. After the bonding procedure, the speciments were subjected to 2 different immersion regimens. While the eight of the groups were immersed in simulated gastric solution of pH 1.5, the other half of the groups were immersed in the artificial saliva with pH 7. Immersion regimes were carefully carried out for 8 days; each immersion lasting for five minutes. The regime was distributed over a 12-hour period. At the end of immersion period, all the tooth surfaces except 1 mm wide zone around the margins of the bonded retainer were painted with nail varnish. After the nail varnishing process is done to the all samples, they were immersed in 0.5% basic fuchsine solution for 24 hours at room temperature. Afterwards the specimens were sectioned parallel to the lingual retainer wire with a dental diamond saw (Meisinger, Neuss, Germany) and evaluated under microscope (20x magnification) at enamel adhesive interfaces from mesial and distal margins. Microleakage was observed in all groups. There was no significant difference between microleakage scores of mesial and distal margins (p >0.05). There was no statistically significant difference between two different orthodontic retainer types microleakage scores in any of the groups at the p<0.05 significance level. Among all groups, the microleakage score of the group immersed in the solution of pH 1.5 showed statistically significantly higher result than the group which is exposed to a solution of pH 7. The acidity of the pH solution increased the microleakage score. The microleakage score of the group which has not gone under a previous air abrasion of the enamel showed statistically significantly higher result than the group which has undergone a previous air abrasion of the enamel. Among the adhesive systems which were used, it was found that all of the groups which have undergone to an immersion to pH 1.5 have not shown any statistically significant result with microleakage. When the speciments were immersed in the solution of pH 7, the adhesive systems showed statistically significant results with their microleakage scores. The flowable composite exposed higher microleakage score than the Transbond LR composite. Keywords: microleakage, retainers, air abrasion, adhesives, GERD