Bonding and Debonding From Metal to Ceramic: Research and its Clinical Application

Over the last 50 years, the bonding of various resins to enamel has also developed a niche in orthodontics. The direct bonding technique revolves around the concept of attaching orthodontic appliances to tooth structure using adhesives, and this technique has become a foundation of contemporary orthodontics. Although the specific techniques and materials used in bracket bonding have changed, the basic procedure has remained relatively constant. In general, the technique for orthodontic bonding includes 3 steps using an etchant, a primer, and an adhesive. More recently, these 3 steps have been combined into 2 or even 1 step. At the present time, numerous bonding materials, techniques, and protocols have been established that have the ability to provide the clinician with adequate bracket/adhesive/enamel (shear bond strength [SBS]), over the course of treatment. However, bracket SBS is influenced by many variables which may or may not be under the control of the clinician. It is important for the clinician to be aware of how these variables affect SBS and apply this knowledge in their selection of the optimal bonding adhesive/technique. In addition, because of the lack of standardization of bond strength testing, the clinician should be cognizant that accurately comparing bond strengths between different studies may be difficult.