Evaluation of restorative and implant alloys galvanically coupled to titanium.
OBJECTIVE
As the success of implants leads to their increasing use in restorative dentistry, attention should be devoted to the galvanic combination of restorative materials with titanium. This paper used continuous corrosion potential monitoring in conjunction with zero-resistance ammetry to obtain galvanic corrosion properties of restorative and implant materials coupled with titanium (ASTM F67-Grade II).


METHODS
Direct coupling or galvanic experiments were conducted on eight restorative and implant materials coupled to titanium. Deaerated artificial saliva solution in a specifically designed corrosion cell simulated an oral crevice situation. Open circuit potentials (Eo.c.) of each material in the couple, coupled corrosion potentials (Ecouple corr), coupled corrosion current density (lcouple corr) and the resultant charge transfer were monitored. The results were analyzed using single factor ANOVA and Duncan's multiple range tests.


RESULTS
Noble restorative (Au-, Ag-, and Pd-based) alloys coupled to titanium were found to be least susceptible to galvanic corrosion. Co-Cr-Mo, Ni-Cr and Fe-based alloys coupled to tatanium were found to be moderately susceptible to galvanic corrosion due to mechanical-electrochemical interaction. Ni-Cr-Be alloy coupled to titanium was found to be highly susceptible to galvanic corrosion. The in vitro test results for the titanium/Disperalloy combination does not concur with the published clinical performance of this combination, and thus warrants further investigation.


CONCLUSIONS
From the data obtained in this study and current literature profiles, acceptable restorative couples were developed for use as clinical guidelines in restorative dentistry.
Venugopalan
R
R
Department of Biomedical Engineering, University of Alabama at Birmingham, USA. venugr16@eng.uab.edu
Lucas
L C
LC
D000704:Analysis of Variance; D003343:Corrosion; D003722:Dental Alloys / Q000737:chemistry*; D015921:Dental Implants; D017267:Dental Prosthesis Design; D004563:Electrochemistry; D004570:Electrogalvanism, Intraoral; D005069:Evaluation Studies as Topic; D006801:Humans; D008422:Materials Testing; D014025:Titanium / Q000737:chemistry*
D003722:Dental Alloys; D015921:Dental Implants; D014025:Titanium