Comparative Efficacy of Er,Cr:YSGG Laser, Electrolytic Cleaning, and Chlorhexidine for the Decontamination of Sandblasted, Large-Grit, Acid-Etched (SLA) Implant Surfaces: An In Vitro Controlled Study.

BACKGROUND

Predictable decontamination of exposed implant surfaces remains difficult to achieve in peri-implantitis therapy. Rough sandblasted, large-grit, acid-etched (SLA) surfaces and implant thread geometry may promote biofilm retention and limit the effectiveness of chemical antiseptics and mechanical instrumentation.

OBJECTIVE

This controlled in vitro study compared the antimicrobial efficacy of three clinically relevant decontamination approaches: 0.12% chlorhexidine (CHX), GalvoSurge electrolytic cleaning, and erbium, chromium: yttrium-scandium-gallium-garnet (Er,Cr:YSGG) laser irradiation against Staphylococcus aureus biofilms formed on Straumann SLA tissue-level implants in a standardized peri-implant defect model.

METHODS

Forty-eight Straumann SLA tissue-level implants were fixed in custom three-dimensional (3D)-printed peri-implant defect models and individually contaminated with Staphylococcus aureus and incubated in brain-heart infusion broth for 72 hours at 37°C. Implants were randomly assigned to four groups (n = 12/group): untreated control, CHX immersion for 60 s, GalvoSurge electrolytic cleaning for 120 s, or Er,Cr:YSGG laser treatment (2780 nm; 2.5 W; 30 Hz; 70% water; 60% air; 30 s). Residual viable bacteria were recovered using a standardized microbrush protocol and expressed as log10(colony-forming units (CFU)/implant).

RESULTS

Mean log10(CFU/implant) values were highest in the untreated control group (5.09 ± 0.33), followed by CHX (4.03 ± 0.12), GalvoSurge (3.77 ± 0.25), and Er,Cr:YSGG laser treatment (2.52 ± 0.39). The corresponding reductions relative to control were approximately 1.06 log10 for CHX, 1.32 log10 for GalvoSurge, and 2.57 log10 for laser treatment. Statistical analysis demonstrated a significant treatment effect (p < 0.001), with laser irradiation achieving the greatest reduction in viable bacterial counts under the tested conditions.

CONCLUSION

All active protocols reduced viable Staphylococcus aureus counts compared with untreated implants. Within the limitations of this single-species in vitro model, Er,Cr:YSGG laser irradiation achieved the greatest reduction, whereas GalvoSurge and CHX resulted in moderate and comparable decreases. Further studies incorporating multispecies biofilms, assessment of implant surface integrity, and clinically relevant outcomes are warranted.