Peri-implant Supra-crestal Fiber Adherence to Provisional Abutment on Immediate Implant

Objectives: The insertion of a provisional abutment at the time of immediate implant appears to help minimize subsequent remodeling and loss of bucco-lingual alveolar dimension. Evidence of adhesion of the peri-implant sulcus soft tissue to the surface of acrylic provisional abutment would provide a biologic basis for bleeding upon removal of custom acrylic abutment and improvement in alveolar ridge stability observed during healing. The purpose of this SEM study was to microscopically evaluate acrylic custom provisional abutments for the presence of cellular adherence, after initial disconnection from immediate implants.
Methods: Custom provisional abutments disconnected from post-extraction immediate implants were disconnected for the first time after 5 months of healing. Upon disconnection, bleeding from peri-implant sulcus and plaque free score of <80% were clinically confirmed. The abutments were processed and observed under Scanning Electron Microscope (Quanta 200, FEI Company) for the presence of cell adherence on the peri-implant sulcus interface of disconnected abutments. The immunogold labeling was used to specify the cell type along with positive and negative controls.
Results: (1) The custom provisional restorations with peri-implant sulcus bleeding at the time of the first disconnection showed well-spread fibroblasts like structures on its surfaces. Immunogold-labelled fibroblasts were confirmed under backscattered microscope. (2) Filopodia inserting into the porous surface of the custom provisional abutment were also observed. The micro porosity (approximately 60 - 80 µm) of the acrylic provisional abutments appears favorable for fibroblasts to initiate cell adherence.
Conclusions: The use of custom provisional restorations made with acrylic may promote supra-crestal cell-mediated adherence of peri-implant soft tissue following immediate implant placement.