Representative survey on the reprocessing of endodontic instruments in Germany

Aim The aim of the study was to review the implementation of hygiene guidelines for the reprocessing of endodontic files in a representative survey and to determine the time needed for the procedure.Methods A questionnaire with nine items was sent to 4,000 German dentists. In addition to obtaining personal information, it asked for the total time required for the reprocessing of instruments and contained specific questions about the cleaning procedure in order to assess whether the requirements of the German Federal Ministry of Health, as defined by the Robert Koch Institute, were complied with. Approval by the Ethics Committee was obtained. The data were analysed statistically using the Chi-square test and Cramer's V as a measurement of effect size.Results The response rate was 29.4% (n = 1,177/4,000). On 59 questionnaires, answers to several questions were missing; 1,118 questionnaires (28.0%) could be included in the evaluation. With effect sizes between 0.12 and 0.21, the survey could be classified as statistically representative of German dentists in terms of age and gender. The guidelines were adhered to by 31.7% (n = 354/1118) of respondents, while 68.3% (n = 764/1118) adhered to them either not fully, or not at all (P < 0.001). There were no significant differences in adherence to guidelines between younger (up to 44 years) and older (45 years and above) dentists (P = 0.31) or between women and men (P = 0.194). The reported time for cleaning a patient-related instrument set was more than nine minutes for 68.1% of respondents, not including the time needed for sterilisation; 5% of respondents treated files as single-use instruments.Conclusions The guidelines of the German Federal Ministry of Health for cleaning, disinfecting and sterilising endodontic files are widely disregarded in Germany. The designation and use of endodontic files as single-use instruments should be considered.