Both sides featured the same distribution of samples , including one untreated control sample ( group A ) and three samples with brackets ( Victory APC II ) bonded to their surface after conditioning with a self-etching non-fluoride primer ( iBond Gluma Inside ; group B ) , a self-etching fluoride-releasing primer ( Transbond Plus ; group C ) , or traditional acid-etching with 35 % phosphoric acid and Transbond XT ( group D ) .