Influence of abutment material on peri-implant soft tissues in anterior areas with thin gingival biotype: a multicentric prospective study

PurposeThe aim of the present clinical trial was to analyze, through spectrophotometric digital technology, the influence of the abutment material on the color of the peri-implant soft tissue in patients with thin gingival biotype. Material and methodsThirty-seven patients received an endosseous dental implant in the anterior maxilla. At time of each definitive prosthesis delivery, an all-ceramic crown has been tried on gold, titanium and zirconia abutment. Peri-implant soft-tissue color has been measured through a spectrophotometer after the insertion of each single abutment. Also facial peri-implant soft-tissue thickness was measured at the level of the implant neck through a caliper. A specific software has been utilized to identify a standardized tissue area and to collect the data before the statistical analysis in Lab* color space. E parameters of the selected abutments were tested for correlation with mucosal thickness. Pearson correlation test was used. ResultsOnly 15 patients met the study inclusion criteria on peri-implant soft-tissue thickness. Peri-implant soft-tissue color was different from that around natural teeth, no matter which type of restorative material was selected. Measurements regarding all the abutments were above the critical threshold of E 8.74 for intraoral color distinction by the naked eye. The E mean values of gold and zirconium abutments were similar (11.43 and 11.37, respectively) and significantly lower (P=0.03 and P=0.04, respectively) than the titanium abutment (13.55). In patients with a facial soft-tissue thickness 2mm, the E mean value of gold and zirconia abutments was significantly lower than that of titanium abutments (P=0.03 and P=0.04, respectively) and much more close to the reference threshold of 8.74. ConclusionsFor peri-implant soft tissue of 2mm, gold or zirconia abutments could be selected in anterior areas treatment. Moreover, the thickness of the peri-implant soft tissue seemed to be a crucial factor in the abutment impact on the color of soft tissues with a thickness of 2mm.