Effect of Tribocorrosion on Mechanical Behavior of Titanium Dental Implants: An In Vitro Study

Abstract

Background/Objectives: Peri-implantitis often necessitates surgical intervention, with implantoplasty being proposed as a decontamination method in resective surgeries. This mechanical cleaning technique aims to halt disease progression by removing bacterial colonies. However, implantoplasty may compromise mechanical properties, reduce corrosion resistance, and lead to cytotoxic effects due to titanium particle release. This study aimed to evaluate the corrosion and mechanical resistance of implantoplasty-treated dental implants, with and without bacterial contamination. Methods: Twenty dental implants were divided into three groups: control (C), implantoplasty (IP), and implantoplasty with bacterial contamination (IPC) using Streptococcus aureus and Porphyromonas gingivalis. Scanning electron microscopy was used to assess surface morphology. Fatigue life curves were obtained using a Bionix servohydraulic machine, and electrochemical corrosion tests were conducted to measure corrosion potentials and intensities. Results: The IPC group demonstrated significantly lower fatigue resistance and higher susceptibility to corrosion compared to the control and IP groups. Fatigue life decreased by 21.7%, and corrosion current density (ICORR) increased from 0.025 mu A/cm2 (control) to 0.089 mu A/cm2 (IP) and 0.122 mu A/cm2 (IPC). Corrosion potential (ECORR) shifted from -380 mV (control) to -450 mV (IP) and -495 mV (IPC). Surface defects caused by bacterial colonization facilitated stress concentration and crack initiation during fatigue testing. Conclusions: Dental implants treated with implantoplasty and exposed to bacterial contamination exhibit significantly reduced mechanical and corrosion resistance. Bacterial activity exacerbates surface vulnerability, leading to titanium loss and pitting corrosion. These findings highlight the clinical implications of bacterial colonization on implantoplasty-treated surfaces.