Evaluation of residual contamination on healing abutments after cleaning with a protein-denaturing agent and detergent

Objective: This study evaluated the cleaning potential of a protein-denaturing agent with or without anionic detergent by monitoring the residual contamination on healing abutments used for dental implant treatment. Method and materials: Forty contaminated healing abutments removed from patients were randomized and immediately treated with differing cleaning methods; either Method A (presoaking in 1% sodium dodecyl sulfate followed by ultrasonication with 4 mol/L guanidine hydrochloride), or Method B (soaking in distilled water followed by ultrasonication with 4 mol/L guanidine hydrochloride) was used. Samples were stained with phloxine B and photographed using a light microscope. The proportion of stained and contaminated areas on each healing abutment was then calculated using Image J. The surface was examined with a scanning electron microscope and energy-dispersive x-ray spectroscopy. Results: The percentages of contaminated surfaces of the screwdriver engagement region, upper body, and lower body for methods A and B were 50% and 38%, 10% and 80%, and 38% and 18%, respectively. There was a statistically significant difference (engagement region [P .001], upper body [P = .043], and lower body [P = .017]; Mann-Whitney) regarding the residually stained areas between the two cleaning methods. No surface alterations were seen by scanning electron microscopy. Energy-dispersive x-ray spectroscopy confirmed that the cleaned surfaces of the healing abutments revealed no signs of organic contamination. Conclusion: Although the combination of a strong denaturing agent and detergent effectively cleaned contaminated healing abutments, perfect cleaning was not always possible, indicating that the reuse of healing abutments in different patients is not recommended. Parole chiave: anionic detergent, decontamination, healing abutments, protein denaturing agent, ultrasonic cleaning