The evaluation of root surface modifications after different subgingival mechanical instrumentation techniques – an in vitro study

Objectives. The aim of this in vitro study was to observe through scanning electron microscopy (SEM) the surface morphology of root samples treated with different mechanical instrumentation methods and the additional application of a nano-colloidal silver-based antiseptic solution. Material and methods. Root samples were prepared from extracted molars and divided in four groups: group 1 of samples was instrumented with Gracey curette (7/8), group 2 of samples was instrumented with ultrasonic tip 1S, group 3 of samples was instrumented with ultrasonic tips 1S plus H4R/L, group 4 of samples was treated with ultrasonic tips 1S plus H4R/L and application of the silver-based antiseptic solution. All samples were then subjected to SEM examination. Outcomes. Group 1 of samples presented a smoother surface compared to the samples in the other groups. Group 2, 3 and 4 displayed superficial grooves parallel to the direction of action of the ultrasonic tip. In group 3 and 4, root planning with tip H4R/L did not ameliorate the smoothness of the surface. The smear layer was present, regardless the instrumentation method. In group 4, the additional application of the antiseptic solution did not influence the surface morphology or the amount of smear layer. Conclusions. Gracey curettes created a smoother radicular surface compared to ultrasonic tips. Smear layer was obvious on the radicular surfaces, no matter the instrumentation method. The application of the silver-based antiseptic solution had no additional impact on surface morphology.