ÅKE ERICSON*,MARGARETA MOLIN, BO BERGMAN. (Dept of Prosthetic Dentistry, Faculty of Odontology, Umeå university, S-901 85 UMEÅ)
Present study aimed to investigate how different materials and different conical tapers at dry and wet conditions influence the retention of conical crowned retained dentures. Twelve patrix/matrix pairs, four in gold alloy, four in machine duplicated/spark eroded unalloyed titanium and four in casted unalloyed titanium were fabricated. For each material two sets were made with a conical taper of 4° and two with a taper of 6°. The retention was measured with a computer furnished with a data acquisition board and software Lab-NuBus® technology. Registration of the retention was done for every patrix/matrix pair at four given application loads, 30, 50, 70, and 90 Newton. The analysis of the experiment was based on Anova where the five factor interaction was assumed to be zero. For every combination in both sets the retention increased with higher application force but none of the separate factors, taper angle, material, and application force did significantly influence the retention.
For all tested combinations, a combination at four-factor level showed a significantly (p<0.01) higher retention combining material, taper angles and application force.
This work was supported by Nobelpharma Norden AB.