Crystal growth on the outer enamel surface--an alternative to acid etching.

Over the past 2 years an increasing concern has developed about the possible iatrogenic effects of phosphoric acid-etch bonding techniques on the enamel surface. There is an evident need to develop a mechanical or chemical retention system that would not alter (or would minimally alter) the outer enamel surface. An alternative to the conventional phosphoric acid etch technique has been developed. A preliminary clinical trial showed promising performance under normal clinical conditions. These results were achieved with a minimal loss of surface enamel as evidenced by scanning electron microscopy. Debonding and cleanup were greatly facilitated. Creating a micromechanical retentive surface by the formation of a crystalline interface is a potential alternative to phosphoric acid etching.