Spectrophotometric analysis of fluorescent zirconia abutments compared to “conventional” zirconia abutments: A within subject controlled clinical trial

Abstract Background Zirconia abutments are frequently used for implant‐supported single crowns. Even though demonstrating esthetic benefits compared to metal abutments, zirconia abutments lead to an increased brightness of the peri‐implant mucosa compared to natural teeth and are not ideal from an esthetic point of view. Purpose To test whether or not a fluorescent hybrid zirconia abutment offers superior esthetics compared to a non‐fluorescent one‐piece zirconia abutment based on spectrophotometric analysis. Materials and Methods In 24 patients with 24 single‐tooth implants, 2 types of reconstructions were fabricated: a directly veneered one‐piece zirconia abutment/crown (control) and a directly veneered fluorescent hybrid zirconia abutment/crown (test). Spectrophotometric assessment was performed: prior to abutment insertion (WA), at abutment try‐in (A), at the try‐in of the final crowns (C). Color differences (ΔE) were assessed compared to the gingiva of natural teeth (T) and between the reconstructions. Results At abutment try‐in, ΔE values were 8.49 ± 3.59 for AControl and 8.27 ± 4.03 for ATest compared to T. At crown insertion, ΔE values were 7.61 ± 4.03 for CControl and 8.32 ± 3.57 for CTest compared to T. The difference in ΔE values between AControl and ATest was 0.23 ± 2.54 (P = .37), whereas the difference in ΔE values between CControl and CTest was −0.66 ±3.45 (P = .48). For all cases with a mucosal thickness ≤2 mm, the comparison between CControl and CTest was significant in favor of the control group (P = .03). Conclusions Both types of reconstructions were similar in terms of esthetics. Incases with a mucosal thickness of <2 mm, the soft tissue discoloration compared to the natural gingiva was more pronounced for the fluorescent hybrid zirconia reconstructions.