Decalcification and bond failure: A comparison of a glass ionomer and a composite resin bonding system in vivo

Decalcification during orthodontic treatment is a serious problem. A glass ionomer agent is now available to bond orthodontic brackets as an alternative to composite resins. This prospective study was a clinical trial to determine if a glass ionomer bonding system (Fuji Ortho LC) decreases the incidence of decalcification without increasing the amount of bonding failures. A prospective clinical trial with 16 patients encompassing a total of 298 teeth was conducted. The 149 control teeth were bonded with a light-cured composite resin (Reliance Light Bond) whereas the 149 experimental teeth were bonded with the light-cured glass ionomer agent. Patients were followed for a period of 12 to 14 months. All teeth were evaluated for breakage (bonding failure rate), and all maxillary anterior teeth (96) were evaluated for decalcification on a graded scale. The glass ionomer failure rate was 24.8%, and was higher than the composite resin failure rate of 7.4% (P <.001). There were more glass ionomer bond failures in 12 of 16 patients (P <.001). Enamel decalcification was similar in the 2 bonding systems.