Influence of three carboxylic primers on bonding of an adhesive resin to titanium

Yohsuke Taira, DDS, PhD, Mitsuru Atsuta, DDS, PhD, and Hideo Matsumura, DDS, PhD

Division of Fixed Prosthodontics and Oral Rehabilitation, Nagasaki University Graduate School of Biomedical Sciences, Nagasaki, Japan

Purpose: The purpose of this study was to evaluate the influence of three primers on bonding to titanium of an adhesive luting agent.
Materials and Methods: The luting agent consisted of 4-methacryloyloxyethyl trimellitate anhydride (4-META), methyl methacrylate (MMA), and tri-n-butylborane (TBB) initiator. Forty pairs of disk specimens were prepared from 99.9% titanium metal, air-abraded with 50 μm grain size alumina, primed with one of the three carboxylic primers (Acryl Bond, MR Bond, and Primer B), and bonded with the 4-META/MMA-TBB resin along with an unprimed control. Shear bond strength was determined after 24 hours of immersion in 37°C water, and after 100,000 cycles of thermocycling at 4°C and 60°C.
Results: Bond strength was negatively affected by thermocycling and by the use of each of the three carboxylic primers. After 100,000 thermocycles, the average bond strengths were categorized statistically into three levels (p<0.05): a higher group (unprimed, 37.0 MPa), medium groups (Acryl Bond, 24.4 MPa; and MR Bond, 25.5 MPa), and a lower group (Primer B, 17.8 MPa).
Conclusion: Each of the three carboxylic primers reduced the bonding between 4-META/MMA-TBB resin and titanium metal.
(Int Chin J Dent 2002; 2: 116-120.)

Clinical Significance
: There are some cases where primer should not be used. Clinicians need be informed of the longevity of resin-bonded titanium restorations.
Key Words: bonding, carboxylic acid, thermocycling, titanium.