Cleaning Efficacy and Surface Alterations of Titanium and Zirconia Implant Abutments Following Mechanical Instrumentation: An In Vitro Study.

OBJECTIVES: To evaluate the cleaning efficacy, quantitative and qualitative surface modifications of titanium (Ti) and zirconia (Zr) abutments following instrumentation with twelve mechanical instrumentation modalities. MATERIALS AND METHODS: Twenty-four Ti and twenty-four Zr abutments were divided by marginal grooves into 36 test and 12 control surfaces per material. Test abutments were mounted in a custom peri-implant mucositis model and treated in triplicate with twelve modalities: glycine (GPAP) and erythritol (EPAP-5 s and 20 s) air-polishing; prophylaxis cup with paste; plastic, titanium and stainless-steel (SS) curettes; and titanium, polyether-ether-ketone (PEEK) sonic, PEEK ultrasonic, SS sonic and SS ultrasonic tips. Post-treatment analyses included stereomicroscopy, vertical scanning interferometry (VSI), scanning electron microscopy (SEM) and energy-dispersive X-ray spectroscopy (EDS). RESULTS: Air-polishing was associated with a favourable combination of high cleaning efficacy and preserved native surface morphology. SEM and VSI analyses revealed scratching, gouging and material loss on titanium abutments following instrumentation with metallic devices, whereas EPAP preserved surface morphology. Zirconia abutments demonstrated minimal topographical disruption across most modalities; however, surface residues and material smearing were detected following nearly all treatments except EPAP. EDS analyses identified elemental surface transfer on zirconia abutments following instrumentation with stainless-steel and titanium instruments. CONCLUSION: All mechanical instrumentation modalities altered titanium and zirconia surfaces to varying degrees. On titanium, EPAP was associated with a favourable combination of high cleaning efficacy and preserved native surface morphology. On zirconia, both air-polishing modalities achieved high cleaning efficacy with minimal topographical alteration.