Impact of Erythritol Air-Polishing on Titanium Implant Surface Properties and Bacterial Colonization: An In Vitro Study

Objectives: This study aimed to investigate the effect of erythritol air-polishing on implant surface topography and bacterial colonization, and to determine the antimicrobial activity of erythritol powder. Materials and methods: Titanium implants, with machined/acid-etched hybrid design, were divided into three groups: erythritol air-polishing for 1 min (E1), 5 min (E5), and untreated control. Surface analysis was performed using a stylus profilometer and scanning electron microscope (SEM). To test the ability to prevent biofilm formation, four bacteria strains (Staphylococcus aureus, Klebsiella pneumoniae, Streptococcus mutans, Streptococcus sanguinis) were separately cultured on five implants per group and colony counting was performed. The intrinsic erythritol antibacterial activity was investigated by means of minimum inhibitory concentration against the same strains. Results: At SEM analysis implant surfaces appeared unaltered by air-polishing and presented increasing amount of residues depending on the treatment duration. Machined surfaces exhibited no significant differences in roughness parameters between the groups. On acid-etched surfaces, E5 presented significantly lower Ra (vs. E1 and control) and Rz (vs. control). The count of colonies was significantly lower for all bacterial strains on treated implants as compared to control, with E1 and E5 being equally capable to reduce by 1.5 log bacteria growth. Erythritol antimicrobial activity against all tested bacterial strains was confirmed. Conclusions: The proposed erythritol air-polishing protocols did not alter implant surfaces and the antimicrobial properties of erythritol are conserved by the titanium implant surfaces. Clinical relevance: Erythritol air-polishing could be repeatedly used in supportive peri-implant care programmes.