title: Abutment Material Effect on Peri-implant Soft Tissue Color and Perceived Esthetics.
abstract: OBJECTIVE
  The purpose of this study was to evaluate the effect of implant abutment material on peri-implant soft tissue color using intraoral spectrophotometric analysis and to compare the clinical outcomes with patient and clinician perception and satisfaction.
  
  
  METHODS
  Thirty patients and four prosthodontic faculty members participated. Abutments were zirconia, gold-hued titanium, and titanium. Peri-implant mucosa color of a single anterior implant restoration was compared to the patient's control tooth. Spectrophotometric analysis using SpectroShadeTMMicro data determined the color difference (ΔE, ΔL*, Δa*, Δb*) between the midfacial peri-implant soft tissue for each abutment material and the marginal gingiva of the control tooth. Color difference values of the abutment groups were compared using ANOVA (α = 0.05). Patient and clinician satisfaction surveys were also conducted using a color-correcting light source. The results of each patient and clinician survey question were compared using chi-square analysis (α = 0.05). Pearson correlation analyses identified the relationship between the total color difference (ΔE) and the patient/clinician perception and satisfaction, as well as between ΔE and tissue thickness.
  
  
  RESULTS
  Zirconia abutments displayed significantly smaller spectrophotometric gingival color difference (ΔE) compared to titanium and gold-hued titanium abutments (respectively, 3.98 ± 0.99; 7.22 ± 3.31; 5.65 ± 2.11; p < 0.05). Among ΔL*, Δa*, and Δb*, only Δa* (red-green spectrum) showed significant difference between groups. There was no significant correlation between measured soft tissue thickness and ΔE, but thick gingival phenotype, determined by a probe test, demonstrated a smaller ΔE than thin phenotype (4.82 ± 1.49; 6.41 ± 3.27; p = 0.097). There was no statistical difference in patient or clinician satisfaction among abutment materials, and no correlation between ΔE and the patient and clinician satisfaction. Patient satisfaction was significantly higher than clinician, and patient-perceived differences were lower than clinicians' (p < 0.01). Clinicians' satisfaction was higher for gingival (pink) esthetics than crown (white) esthetics (p < 0.05).
  
  
  CONCLUSIONS
  Peri-implant mucosa with zirconia abutments demonstrated significantly lower mean color difference compared to titanium or gold-hued titanium abutments as measured spectrophotometrically; however, no statistical difference in patient or clinician perception/satisfaction among abutment materials was demonstrated. Patients were significantly more satisfied than clinicians.
authors.affiliation: Department of Restorative Dentistry, University of Illinois at Chicago College of Dentistry, Chicago, IL.
authors.forename: Aram
authors.initials: A
authors.lastname: Kim
authors.affiliation: Department of Restorative Dentistry, University of Illinois at Chicago College of Dentistry, Chicago, IL.
authors.forename: Stephen D
authors.initials: SD
authors.lastname: Campbell
authors.affiliation: Department of Restorative Dentistry, University of Illinois at Chicago College of Dentistry, Chicago, IL.
authors.forename: Marlos A G
authors.initials: MA
authors.lastname: Viana
authors.affiliation: Department of Restorative Dentistry, University of Illinois at Chicago College of Dentistry, Chicago, IL.
authors.forename: Kent L
authors.initials: KL
authors.lastname: Knoernschild
mesh_terms: D003116:Color; D003442:Crowns; D000044:Dental Abutments; D019250:Dental Implants, Single-Tooth; D004954:Esthetics; D006801:Humans; D014025:Titanium; D014070:Tooth; D015040:Zirconium
chemical_list: D015040:Zirconium; D014025:Titanium
keywords: Peri-implant soft tissue; clinician perception; implant esthetics; implant restoration; patient satisfaction; titanium abutment; zirconia abutment