Evaluation of different debridement strategies for implant-abutment connections: An in vitro study

Abstract

Statement of problem. Technical complications, including abutment fracture, are a clinical reality. After retrieving failed components, re-establishing a reliable implant-abutment connection is essential, but recommendations on how to clean the interface are lacking. Purpose. The purpose of this in vitro study was to evaluate different clinical debridement strategies for removing titanium powder from an implant-abutment interface with regard to their efficacy and associated risk of damaging the interface. Material and methods. Specimens (n=5) were assembled from previously cut implant halves, which were then contaminated by placing titanium powder inside the implant-abutment connection. Activated rinsing, airflow, and an ultrasound scaler, as well as combinations thereof, were then used to clean the implant-abutment connections. Both parts of each specimen were rated under a light microscope with respect to contamination and damage. In addition, abutments were placed in intact implants (n=10), which had previously been contaminated and cleaned, to record torque curves and abutment stability. Statistical analysis of ratings was based on Kruskal-Wallis tests and the Nemenyi All Pairs test with single-step P value correction, while abutment stability and torque were analyzed using analysis of variance and Tukey HSD tests (α=.05). Results. Erythritol as an abrasive medium led to significantly greater contamination than the scaler (P=.002), activated rinsing (P=.021), and airflow with sodium bicarbonate combined with either conventional (P=.002) or activated rinsing (P=.007). Greater damage was also observed with erythritol because of accumulations of the abrasive media, while scratches were seen after scaler application. Airflow using sodium bicarbonate in combination with activated rinsing showed the lowest level of damage (versus scaler P=.030). Using conventional (P=.010) or activated (P=.029) rinsing, airflow treatment led to a significant reduction in contamination. The scaler led to a significant decrease in abutment stability (P=.048), while activated rinsing and the combination of airflow and activated rinsing did not significantly affect abutment stability. Abutments placed in implants previously contaminated and cleaned required greater torque as compared with original implants (versus activated rinsing, P=.009). Conclusions. Activated rinsing constituted the best technique for cleaning implant-abutment connections. Cleaning efficiency can be enhanced with airflow using sodium bicarbonate as an abrasive medium. (J Prosthet Dent 2023;130:738.e1-e8)