Fig. 1: Apply Etch-Rite™ to the cavity prep for 15 seconds

Fig. 2: Rinse and leave dentin moist for wet bonding technique

Fig. 3: Use DenTASTIC™ UNO™ for light cure, or UNO + DUO for self-cure or dual cure applications

Fig. 4: Light cure for only 10 seconds

Basic Rules:

1. Etch or sandblast surfaces, as indicated.
2. Leave dentin surfaces slightly moist. Moisture should be visible on the surface, but it should not form a pool of water.
3. For direct bonding of composites to dentin/enamel, etch tooth and apply two coats of DenTASTIC UNO to the wet dentin/enamel surface. It is best to build up a thick layer of adhesive. Light cure for 10 seconds.
4. For direct bonding of composite to metal, sandblast metal, apply one coat of DenTASTIC UNO to the metal surface and light cure for 10 seconds.
5. For direct bonding of composite to porcelain, etch porcelain with porcelain etch gel, apply silane and dry with clean moisture-free air, then apply one coat of DenTASTIC UNO and light cure for 10 seconds.
6. For bonding indirect restorations, etch dentin and enamel and apply one layer of DenTASTIC UNO to the tooth surface, thin this layer with a gentle stream of air and light cure for 10 seconds. Apply one coat of DenTASTIC UNO to the restorative surface and thin this layer. Light curing the restorative surface is not necessary. Cement restoration with resin cement.

Helpful Hints:

• If not proceeding with bonding immediately after etching, the tooth surface can be kept wet by placing wet cotton on the exposed dentin.
• For direct composite restorations, when removing the solvent with a gentle stream of air, do NOT thin the adhesive layer. A thick layer of adhesive gives best results. Do not push the adhesive out
  to the sides, which will thin it out; instead, push the adhesive back toward the center.
• When bonding indirect restorations, thin the adhesive layer so that it will not interfere with the seating of the restoration. Light cure UNO on the tooth surface for 10 seconds. Light curing UNO on the restorative surface is not necessary. Cement restoration with resin cement.
• Remember:
  Direct restoration: thick adhesive layer. Indirect restoration: thin adhesive layer.

Dentin is a fiber reinforced tissue consisting of minerals, collagen and water. The mineral component is mostly calcium phosphate in the form of hydroxyapatite. Cutting dentin with a rotary bur produces a smear layer of dentinal debris.

Etching dentin removes the smear layer, dissolves the minerals at the surface exposing the collagen fiber matrix, and slightly opens the dentinal tubules. All the popular dentin etchants (maleic,nitric and phosphoric acid) achieve the same results.

DenTASTIC UNO combines the primer and unfilled resin phases into a single component adhesive. It forms an interlocking matrix with the exposed collagen and dentinal tubules, creating a “hybird layer” that provides extraordinary micromechanical retention. UNO forms an unfilled resin layer to which composite and resin cement will chemically bond with great strength.

1. Sandblast or roughen metal surface to improve micromechanical retention. Tin plate high precious alloys with a simple brush-on technique.

2. Apply DenTASTIC UNO on the metal. UNO micromechanically bonds to sandblasted metal surfaces, and it chemically bonds to the oxides on tin plated and non-precious metal surfaces and to restorative resin and resin cements.

1. Etch porcelain to improve micromechanical retention.
2. Prime porcelain surface with Silane Bond Enhancer. Silane chemically bonds to the silica in porcelain.
3. Apply DenTASTIC UNO over Silane. UNO micromechanically bonds to the etched porcelain and chemically bonds to Silane, restorative resin and resin cements.

This light microscopy section shows the three layers of dentin adhesive interface.

The gray lower portion shows the unaltered dentin with the dentinal tubules cut in cross section. The adhesive primer resin tags appear as small reddish blue dots in the center of the tubules.

The hybrid layer is the blue band across the center of the slide. This is the interlocking matrix formed by the adhesive primer, which is stained blue, and the collagen fibers in the demineralized dentin surface.

The cream color layer at the top is the unfilled resin bonding agent. It has chemically reacted with the surface of the adhesive primer, and this can be seen in the thin light blue band at the top of the blue hybrid layer.

In the 4th generation bonding system, the adhesive primer and unfilled resin bonding agent are separate and are applied in two separate steps.

In the 5th generation one step bonding system, the adhesive primer and unfilled resin are combined in one bottle.A dual cure catalyst is also available for this system.