Consultants’ Comments

• “I have seen almost no marginal discoloration in the restorations I have placed using Prime & Bond NT during the past 12 years.”
• “The lack of sensitivity in these restorations reminds me why this has always been one of my favorite bonding systems.”

Description

Prime & Bond NT is a light-cured, total-etch bonding agent that contains nanofillers of amorphous silicon dioxide, di- and tri-methacrylate resins, PENTA (dipentaerythritol penta acrylate monophosphate), and acetone (solvent). It requires one application followed by a 10-second light cure. Prime & Bond NT is designed to bond composite materials to enamel and dentin. It is also indicated for the bonding of veneers, composites and ceramics, as well as an adhesive cavity varnish for amalgam. When using Prime & Bond NT to bond crowns and veneers, it must be mixed with Self Cure Activator. The purpose of this study was to determine the long-term clinical performance of Prime & Bond NT at 12 years.

Clinical Evaluation Protocol

Prime & Bond NT was used to bond a total of 151 composites, crowns and veneers over 12 years. Self Cure Activator was used with Prime & Bond NT in the bonding of crowns and veneers. At 12 years, 84 of these restorations were available for recall (Figure 1). The type of restoration is shown in Figure 2.

Clinical Observations

Lack of Sensitivity
No patients reported any long-term sensitivity in the teeth where Prime & Bond NT was the bonding agent used (Figure 3).

Resistance to Marginal Discoloration
Eighty-one percent of the restorations evaluated at recall showed no signs of marginal staining (Figure 3). Slight marginal discoloration was observed in 17% of the restorations and moderate marginal discoloration was observed in 2%. No restorations were replaced or repaired as a result of marginal discoloration.

Retention
No restorations placed using Prime & Bond NT debonded during the 12 years in service (Figure 3). One MOD restoration on a premolar fractured and was replaced. One restoration was replaced and extended as a result of recurrent caries. Three restorations were subsequently covered with a crown.

Summary

One hundred fifty-one restorations were placed using Prime & Bond NT as the bonding system over the past 12 years. Eighty-four restorations were available for recall. All received excellent ratings for lack of sensitivity and resistance to marginal discoloration. None of the restorations debonded over the 12-year period. Prime & Bond NT received a 98% clinical performance rating.