Bond strength of Orthodontic Brackets to Enamel with Different Cements

The adhesion to enamel has been extensively studied by many authors and has been proven to be of great importance in an orthodontic treatment.  Each adhesive system has its unique characteristics that makes them appealing to the practitioner and plays a fundamental roll in the selection of a material.

Objectives: this research aims to test and compare the available adhesives systems for an orthodontic usage and the restorative adhesives system. It will test the adhesive strength to enamel.

Methods: This in vitro study used 10 recently extracted premolars, with no extensive cavities, disinfected and placed in water.  The apical third of the root was transversely cut and the remaining tooth was placed on an acrylic disc.  The enamel zone where the orthodontic bracket would be placed was cleaned with a mixture of water and pumice for 10 s and then the bracket was placed along the long axis of each tooth.  The orthodontic adhesives (3M¨ª Unitek Transbond Plus, Monrovia, CA. Lot 388478B) was used on the vestibular surface of each tooth and the restorative system (3M¨ª, Adapter Single Bond 2, St. Paul, MN. Lot N119660) on the lingual surface.  Brackets were loaded in shear with an universal testing machine at a cross-haed speed of 2 mm/min until failure. Data was recorded and bond strength calculated in MPa and analyzed with a one-way ANOVA calculated at 0.05 significance level.

Results: Adper Single Bond 2 showed higher bond strength than Unitek Transbond. Means are shown in table. There was no statistical difference between adhesives studied.

	Bond Strength to enamel
Single Bond 2	8.91 MPa
Transbond Plus	10.7 MPa

Conclusions: Dentin bonding system can be used to bond orthodontic brackets as effectively as the dedicated orthodontic bonding system.