Effect of Different Intraradicular Posts on the Color of the Buccal Gingiva at Teeth Restored with Zirconia Crowns

The purpose of this study was to test whether prosthetic treatment with different intraradicular posts influences the color of the buccal gingiva at teeth restored with zirconia crowns. A total of 31 patients in need of a full-coverage single crown at an endodontically treated premolar, canine, or incisor in the maxilla or the mandible were included. The patients were randomly assigned to receive composite build-ups using titanium (Ti), zirconia (Zi), or glass-fiber (Gf) posts or a build-up using no post at all (NP). All the teeth were restored with veneered zirconia single crowns. Spectrophotometric color measurements of the buccal gingiva were taken at the test teeth prior to and after the prosthetic treatment, and at the contralateral vital control tooth. The differences of the color components Delta L, Delta a, and Delta b and the total color difference Delta E between the test tooth prior to and after treatment and between the test and control tooth were calculated. The color differences were analyzed to determine whether they varied from 0 and 3.7, the threshold for detection by the human eye. Analysis of variance was performed to compare Delta E, Delta L, Delta a, and Delta b in the four post groups. The prosthetic treatment induced a significant color change Delta E in all the groups (Ti: Delta E1 = 6.4 +/- 1.9; Zi: 7.1 +/- 2.0; Gf: 6.2 +/- 3.5; NP: 6.6 +/- 3.5). There was no significant difference between Ti, Zi, Gf, and NP with respect to Delta E, Delta L, Delta a, and Delta b. Gingival color Delta E differed significantly between the test and control teeth before (Ti: Delta E = 6.8 +/- 3.0; Zi: 9.0 +/- 3.5; Gf: 5.7 +/- 2.1; NP: 8.2 +/- 2.8) and after prosthetic treatment (Ti: Delta E = 6.0 +/- 2.8; Zi: 7.1 +/- 2.9; Gf: 7.2 +/- 3.0; NP: 6.9 +/- 2.6). The use of different intraradicular posts (titanium, zirconia, glass fiber) or no post at all did not influence the color of the buccal gingiva at teeth restored with zirconia crowns. There was a significant gingival color difference between endodontically treated teeth and vital control teeth, both before and after prosthetic treatment.