Evaluation of the mechanical cleaning efficacy of dental handpieces.

BACKGROUND

Dental handpieces undergo a decontamination process before reutilization. Thorough cleaning is a prerequisite to effective sterilization, to guarantee safety and prevent cross-infections.

AIM: To assess the cleaning efficacy offered by devices dedicated to dental handpieces.

METHODS

PIDTests©, which are patented tubes made of transparent material and designed to replace handpieces in cleaning devices, were artificially stained by Soil Test© (Browne/STERIS). Three cycles were performed with PIDTests© connected to every handpiece adapter in the four different machines tested: X-Cid 2© (Micro-Mega) with a total of nine PIDTests©; iCare+© (NSK) with nine PIDTests©; DAC Universal© (W&H) with 18 PIDTests©; and BioDA 80© (VR2M) with 24 PIDTests©. A visual evaluation and a biuret reaction test were performed.

FINDINGS: In three of the tested cleaning devices (X-Cid2©, iCare+© and DAC Universal©), all of the PIDTests© showed Soil Test© residues, on the internal and external surfaces indicating cleaning was ineffective. Only the BioDA 80© showed no residual stains on all the PIDTests© and negative biuret reaction test results, making the cleaning effective.

CONCLUSIONS

Manufacturers should optimize the cleaning device parameters, based on the Sinner circle (grouping compensatory parameters which influence the effectiveness of a cleaning process, such as pressure, temperature, time, detergent concentration), to improve cleaning efficacy and enable dental surgeons to ensure the safety. Although PIDTests© are the only tool to provide visual indications on the cleaning efficacy of washer-disinfectors dedicated to handpieces, manufacturers should continue with the development of improved and validated tools to assess cleaning efficacy.