Comparison of the Color Appearance of Peri-implant Soft Tissue with Natural Gingiva Using Anodized Pink-Neck Implants and Pink Abutments: A Prospective Clinical Trial

Abstract

Purpose: The aim of this study was to assess the visual effects of pink-neck implants and pink abutments with respect to the color of natural gingiva. The distribution pattern and magnitude of CIELAB color difference coordinates were studied.

Materials and methods: Forty subjects with a tooth in the maxillary esthetic zone deemed hopeless were recruited. Patients were randomized to either a conventional gray implant or a pink-neck implant. The hopeless tooth was removed and patients received an immediate implant along with an immediate customized provisional prosthesis. The provisional was maintained for 3 months to allow for complete healing of the implants. Two identical CAD/CAM titanium abutments only differing in color (gray and pink) were fabricated along with an all-ceramic zirconia crown. The gray abutment was delivered first with a zirconia crown, and it was replaced with the pink abutment 3 weeks later. Three weeks after insertion of each abutment with the zirconia crown, a spectrophotometer was used to collect the color of the peri-implant mucosa and natural gingiva, so the difference between the two sites could be calculated (ΔL* [difference in lightness], Δa* [difference in green-red axis], Δb* [difference in blue-yellow axis]). The natural gingiva measured was the gingiva of a contralateral or adjacent unrestored tooth. The effect of implant color and abutment on the color difference between peri-implant mucosa and natural gingiva was investigated with a linear regression model using a generalized estimating equation (GEE) approach.

Results: Raw data demonstrated statistically insignificant smaller ΔL*, Δa*, Δb* between peri-implant soft tissue and natural gingiva when the implant was pink versus gray. Further, there were statistically insignificant smaller ΔL* and Δb* between peri-implant soft tissue and natural gingiva when the abutment was pink versus gray. Δa* between peri-implant soft tissue and natural gingiva was significantly smaller when using a pink abutment regardless of the implant type (P < .05).

Conclusion: Using an anodized pink abutment and/or a pink-neck implant minimizes the color difference observed between the peri-implant mucosa and the natural gingiva in the redness spectrum. These advances in technology assist in helping the peri-implant mucosa appear more natural by minimizing the color variance.