Evaluation of vertical marginal adaptation of provisional crowns by digital microscope.

OBJECTIVE

To investigate and compare the degree of vertical marginal discrepancy of four provisional crown materials by digital microscope.

MATERIALS AND METHODS

A total of 100 provisional crowns were fabricated on standardized resin dies by direct technique of provisional fabrication, using four different provisional materials (n = 25): Provisionals Fabricated by Systemp® c and b II, ivoclar vivadent, Schaan, Liechtenstein (group A); ProtempTM Plus, 3M ESPE, Neuss, Germany (group B); Success CD, PROMEDICA, Neumunster, Germany (group C); and Trim® Plus, Bosworth Company, Illinois, USA (group D). The provisional crowns were finished, tried, and locked with a customized device under 15N of vertical axial force. The vertical marginal discrepancy between the crown margin and the resin die was measured in micrometers using digital microscope (KH-7700, Hirox-USA, Inc., NJ, USA) at mid of buccal, lingual, mesial, and distal margin areas by a trained technician.

RESULTS

The mean values obtained for each group were as follows: group A = 129.10 ± 41.64, group B = 123.36 ± 40.94, group C = 89.67 ± 25.34, and group D = 107.24 ± 38.32. Assessment by post hoc Tukey's test at 5% significance level showed a statistically significant difference (P < 0.05) between group C and group D with the other groups. Results of one-way ANOVA showed a statistically nonsignificant difference (P > 0.05) between the means of the four areas of measurement for each group.

CONCLUSION

Marginal discrepancy of the group C (Success CD) was the lowest among the provisionals tested. The mean vertical marginal gap values for the materials tested were found to be with in the clinically acceptable range (<130 μm).