Cement bond strengths of titanium plates.

The success of the oral rehabilitation of implant patients depends not only on the osseointegration of implant fixtures but also on maintaining the integrity of the connection of prosthetic superstructures to these fixtures. It was an objective of the present study to evaluate and compare cement bond strengths among rolled (R), cast (C) and metal-injection-molded (M) commercially pure titanium plates which were bonded with Panavia 21 (Kuraray) and Imperva (Shofu) cements. Two plates (15x5x1 mm) of each R, C, and M were lap-jointed (lap length: 5 mm). The joints were stored in 37 degrees C distilled water for 24 h, followed by tensile tests with an INSTRON system under 1 mm/min crosshead speed. It was found that the bond strength of R with Panavia 21 (PAN) was 5.31 (SD:1.5) MPa and 2.30 (0.83) MPa with Imperva (IMP) cement. These were improved by applying an alloy primer to 7.08 (1.31) MPa and 6.72 (1.63) MPa, respectively. Using PAN with primer application, C and M samples showed bond strengths of 7.99 (1.31) and 7.20 (2.50) MPa, while they were 5.83 (2.15) and 6.79 (2.09) MPa using IMP with primer. There was a significant difference (p<0.01) between PAN and IMP cements for C samples. Additionally, samples were pre-oxidized at 100 degrees C in air for 10 min. Bond strengths of PAN with the primer were 5.69 (2.25), 9.14 (1.28), and 5.60 (3.13) MPa for R, C, and M sample groups. If the cement with the primer was applied immediately after the polishing (instead of pre-oxidized surfaces), bond strengths were improved to 9.14 (1.78) for R, 9.29 (1.85) for C, and 9.36 (1.81) MPa for M sample group. At p<0.05 level, there was a significant difference between surface pre-condition of R and M, but no significance with C.