Novel Method To Obtain Human Non-Separated Histological Samples For The Assessment Of Peri-Implant Soft Tissue Response: A Feasibility Study

Objectives To introduce a standardized and less invasive clinical model that provides histological information on the abutment-mucosa interface in humans.Materials and methods New experimental healing abutments were left in an open healing position on bone-level implants in the interforaminal region of the mandibles in six edentulous patients. The one-piece abutments were hollow cylinder-shaped with two lateral openings that allow for ingrowth of the peri-implant mucosa into the central abutment cavity. After three months of healing, abutments and ingrown mucosa were sampled and processed for histological analysis in a non-separated resin-embedding technique. To test the validity of the new model, the ingrown tissue was compared to the peri-implant mucosa around the same samples.Results None of the experimental abutments exhibited signs of failure, and all samples showed mucosal ingrowth to the inner-abutment cavity. Comparison of ingrown tissue and peri-implant mucosa revealed no significant differences regarding the traits: tissue morphology, quality of collagen fibers, and adherence to the abutment. Ingrown mucosa exhibited a tendency for higher leukocyte infiltration.Conclusions The presented model is a promising approach to reduce invasiveness during the sampling process for human non-separated abutment biopsies.