The Esthetic Effect of Veneered Zirconia Abutments for Single-Tooth Implant Reconstructions: A Randomized Controlled Clinical Trial

PurposeThe purposes of this study were to test whether or not veneering of the submucosal part of zirconia abutments can positively influence the esthetic outcome compared with nonveneered zirconia abutments; to evaluate the influence of the mucosal thickness on the esthetic outcomes of the veneered and nonveneered abutments; and to evaluate the thickness of the peri-implant mucosa compared with the thickness of the gingiva of contralateral tooth sites. Materials and MethodsForty-four single-tooth implants in 44 patients were randomly restored with either cemented (CR) or screw-retained (SR) reconstructions based on white zirconia abutments (CR-W, SR-W) or pink-veneered zirconia abutments (CR-P, SR-P). Esthetic outcome measurements were performed based on a spectrophotometric evaluation of the peri-implant mucosal color. In addition, the thickness of the mucosa was measured. A two-way analysis of variance was conducted to test the effect of veneering (pink vs white) and mucosa thickness (<2mm vs2mm) on the calculated color difference E for pooled data of CR and SR reconstructions (p<.05). ResultsAnalyses grouping the sites according to veneering of the abutments and mucosal thickness demonstrated less discoloration for sites with a veneered abutment irrespective of the mucosal thickness: E 4.501.93 (<2mm) and E 6.88 +/- 2.45 (2mm); CR-P, SR-P) compared with sites without veneering E 9.72 +/- 3.82 (<2mm; CR-W, SR-W) and E 8.31 +/- 2.98 (2mm). The differences between veneered and nonveneered abutments were significant (p=.032). ConclusionsVeneering of zirconia abutments with pink veneering ceramic positively influenced the peri-implant mucosal color.