Brazilian Dental Journal
On-line version ISSN 1806-4760
COSTA, Heloisa Módena Ferreira da; RODRIGUES, Renata Cristina Silveira; MATTOS, Maria da Glória Chiarello de and RIBEIRO, Ricardo Faria. Evaluation of the adaptation interface of one-piece implant-supported superstructures obtained in Ni-Cr-Ti and Pd-Ag alloys. Braz. Dent. J. [online]. 2003, vol.14, n.3, pp. 197-202. ISSN 1806-4760. http://dx.doi.org/10.1590/S0103-64402003000300011.
Several formulations of alternative alloys have been proposed for the substitution of gold-based alloys used in Dentistry. Recently, a Ni-Cr-Ti-based alloy has been introduced. The purpose of this work was to verify the marginal adaptation obtained with one-piece superstructures for implant-supported prostheses obtained in Ni-Cr-Ti alloy, compared to a semi-noble alloy Pd-Ag. Eight superstructures for each alloy were produced over 4 implants in the anterior region of the mandible. The superstructures were placed in a torquemeter and the fixation screw of implant #1 was tightened with a 20 Ncm load with the others loosened (Sheffield test). The unfitness (in mm) was measured using a three-dimensional optical measurer in each implant, in the buccal and lingual aspects. The obtained data were submitted to statistical analysis by the analysis of variance and Tukey's test at 5% level. Significant differences were found for the factors material (p<0.05), with Ni-Cr-Ti pieces better than Pd-Ag ones, and implants (p<0.01). There were no significant differences for the factor position and interactions among factors (p>0.05). Based on the analysis of the data, it is possible to conclude that the Ni-Cr-Ti alloy makes possible the obtainment of one-piece implant-supported superstructures with a smaller misfit compared to the one obtained in Pd-Ag alloy, traditionally indicated for this situation. Additional tests may verify the superiority of the Ni-Cr-Ti alloy.
Keywords : chromium alloys; titanium; implants.