Evaluation of the retention force of double conical crowns used in combination with a galvanoforming and casting fabrication technique.

Purpose: The aim of this study was to measure the in vitro retention force of double conical crowns fabricated using primary galvanoforming and secondary casting techniques and those fabricated using primary casting and secondary galvanoforming techniques under simulated clinical conditions before and after a wear test.

Materials And Methods: Primary galvanoformed crowns (n = 10) with non-noble secondary crowns (n = 10; group A) and primary non-noble crowns (n = 10) with secondary galvanoformed crowns (n = 10; group B) were fabricated. Each primary and secondary crown was embedded in acrylic resin and weighed with a digital balance. Retention forces were then measured using a universal testing device. To simulate wear, specimens were inserted and separated horizonatally 3285 times in wear equipment with artificial saliva. Retention forces and weights of the double crowns were then remeasured. Data were analyzed using paired t-tests and Wilcoxon tests, and the groups were compared using Mann-Whitney U-tests.

Results: In group A, the wear test had a significant influence on the retentive force (p < 0.05), but wear produced no significant difference in weight (p > 0.05). In group B, the wear test had a significant influence on the retentive force (p < 0.05), and wear produced a significant difference in weight (p < 0.05).

Conclusions: The results of this study indicated that the use of different combinations of galvanoforming and casting techniques in the fabrication of conical crowns significantly affected retention force.