Is Enamel Etching Necessary When Placing a Direct Restoration?

Clinicians have different opinions regarding the need to use phosphoric acid with self-etch bonding agents. A sampling of questions from dental professionals to customer support includes:

• Are the bond strengths to uncut enamel using a self-etch product as high as with a total-etch product?
• Should uncut enamel be etched by phosphoric acid before using the self-etch product?
• How should the enamel be treated before using a self-etch product?

During this session, the discussion centered on this issue: Why should a clinician apply phosphoric acid when using self-etch agents, as “self-etch” is essentially a “total-etch,” because both etch enamel and dentin by acid monomers. Applying phosphoric acid requires extra steps and could result in technical error.

According to the visiting professors, phosphoric acid-etching is not necessary for standard cavities, even in anterior teeth, because Kuraray self-etch bonds have sufficient bond strength to “cut-enamel,” and the same or higher bond strength to cut-enamel as etch-and-rinse (total-etch) bonds. Dentists have had excellent clinical success placing direct restorations using Kuraray CLEARFIL™ bonding agents without phosphoric acid-etching, even when placing anterior restorations.

It is important to note that not all self-etch products are the same; some may require phosphoric acid for better adhesive retention. In all cases, the adherent surface must be clean for a bonding agent to work effectively.

In addition, clinicians cannot assume that bonding agents of the same generation have the same properties. There are many types of self-etch products available, and they do not perform the same. Not all self-etch products are identical; some bonding agents may require phosphoric acid for better retention.

Anterior case using CLEARFIL SE BOND and MAJESTY Esthetic* (Dr. Naotake Akimoto, Tsurumi University, Japan) *Restorations placed without phosphoric acid-etching.

For further information and to view the supporting figures and illustrations, please see the online interactive pdf, Technical Solutions for CLEARFIL Adhesives, at: https://kuraraydental.com/resources/01_technical_solutions_for_clearfil_adhesives.pdf.