Histological and Immunohistochemical Analysis of Peri-Implant Soft and Hard Tissues in Patients with Peri-Implantitis

Currently, researchers are focused on the study of cytokines as predictive biomarkers of peri-implantitis (PI) in order to obtain an early diagnosis and prognosis, and for treatment of the disease. The aim of the study was to characterize the peri-implant soft and hard tissues in patients with a peri-implantitis diagnosis. A descriptive observational study was conducted. Fifteen soft tissue (ST) samples and six peri-implant bone tissue (BT) samples were obtained from 13 patients who were diagnosed with peri-implantitis. All the samples were processed and embedded in paraffin for histological and immunohistochemical analyses. A descriptive and quantitative analysis of mast cells and osteocytes, A proliferation-inducing ligand (APRIL), B-cell activating factor (BAFF), osteonectin (ON), and proportional to-smooth muscle actin (proportional to-SMA) was performed. We observed the presence of mast cells in peri-implant soft tissue in all samples (mean 9.21 number of mast cells) and osteocytes in peri-implant hard tissue in all samples (mean 37.17 number of osteocytes). The expression of APRIL-ST was 32.17% +/- 6.39%, and that of APRIL-BT was 7.09% +/- 5.94%. The BAFF-ST expression was 17.26 +/- 12.90%, and the BAFF-BT was 12.16% +/- 6.30%. The mean percentage of ON was 7.93% +/- 3.79%, and proportional to-SMA was 1.78% +/- 3.79%. It was concluded that the expression of APRIL and BAFF suggests their involvement in the bone resorption observed in peri-implantitis. The lower expression of osteonectin in the peri-implant bone tissue can also be associated with a deficiency in the regulation of bone remodeling and the consequent peri-implant bone loss.

Automated summary

Researchers studied cytokines as predictive biomarkers of peri-implantitis and characterized the soft and hard tissues in patients with the disease. The presence of mast cells and osteocytes was observed in all samples, and the expression of APRIL and BAFF was associated with bone resorption in peri-implantitis.