Representative survey on the reprocessing of endodontic instruments in Germany

The Use and Reprocessing of Endodontic Files in Saudi Arabia: A Cross-Sectional Study

Objectives This study aimed to assess the awareness, implementation, and compliance with the infection control policy recommended by the Saudi Ministry of Health (MOH) for the use and reprocessing of endodontic files and to examine the association between compliance and gender, experience, clinical ranks, and workplace sector. Methods This was a cross-sectional study conducted using a validated self-administered electronic questionnaire created and distributed to dentists who perform endodontic treatment in Saudi Arabia. Data were collected between June and July 2023. Descriptive statistics were reported as counts and percentages. Comparisons among the demographic groups were done using the Kruskal-Wallis and Mann-Whitney tests. Results A total of 402 dentists completed the survey. The results showed that 76.1% (n=306) of respondents claimed that they were aware of the infection control policy recommended by the Saudi MOH for the use and reprocessing of endodontic files in dental clinics. Only 13.2% (n=53) of dentists used single-use endodontic files, and 36.6% (n=147) did not use an endodontic box in their dental clinics. The most commonly reported method of tracing the number of uses of endodontic files was to write the ID of the patient or the number of uses on the sterilization pouch as reported by 37.6% of participants (n=151). The average compliance score percentage was 63.5 ± 16.7. Most of the respondents showed moderate to high levels of compliance (51.7% (n=208) and 42.0% (n=169) of dentists, respectively). Dentists with less than 5 years of experience showed significantly less compliance than dentists with more than 10 years of experience (p = 0.005). Gender, clinical rank, and workplace sector were not significantly associated with the extent of adhering to the evaluated infection control policy. Conclusions Our findings indicate a relatively high level of compliance with the Saudi MOH policy of using and reprocessing endodontic files. However, critical measures such as the single-use of endodontic files, sterilizing new endodontic files, and using the sterilized endodontic box for each patient need improvement. Hence, this study recommends enhancing awareness through continuous education and training.

Effect of Sterilization on Cyclic Fatigue Resistance of Proflexendo Endodontic Rotary Files

Background:

Proflexendo file (Nexen, Houston, TX, USA) is a recently developed, novel nickel-titanium rotary file. However, several physical properties of the Proflexendo system remain to be investigated.

Objectives:

The aim of this study was to determine the effect of sterilization on cyclic resistance of Proflexendo files.

Material and Methods:

A total of 120 unused Proflexendo rotary files (40 each of file sizes 40/0.04, 30/0.04 and 20/0.06) were used in this study. Each set of files was subdivided into four groups of ten files. Group 1 did not undergo any sterilization (control), Group 2 underwent two rounds (2×) of sterilization, Group 3 five rounds (5×) and Group 4 ten rounds (10×). Cyclic fatigue resistance was tested using an artificial canal with a 5-mm radius curve.

Results:

The nonsterilized size 30/0.04 files had the highest cycles to failure, followed by the nonsterilized size 40/0.04 and 20/0.06 files (P < 0.001). With increasing rounds of sterilization, cycles to failure reduced for sizes 40 (2×, 5× and 10×) and 30 (2×) files compared with nonsterilized sizes 40 (P < 0.05) and 30 files (P < 0.001), respectively.

Conclusion:

Under the conditions of the current study, the results provide preliminary evidence that autoclave sterilization of Proflexendo rotary files reduced their cyclic fatigue resistance, except for size 20 (2× and 5×) and 30 (10×) files, in which resistance increased. Single use of this file is recommended to reduce the risk of separation.

A critical appraisal of studies on cyclic fatigue resistance of engine-driven endodontic instruments

The endodontic literature contains a plethora of studies on static and dynamic cyclic fatigue resistance tests performed on a large array of rotary or reciprocating nickel-titanium endodontic instruments. It was the aim of this review to summarize the currently available evidence to point out the different outcomes from static versus dynamic tests and to assess whether cyclic fatigue tests provide useful data and information for clinical practice. An electronic literature research in the database PubMed was performed using appropriate search terms, and the titles and abstract were screened for relevance. Language was restricted to English. The review reveals marked differences between the results obtained in static and dynamic tests, and also, the results for the same instruments assessed either under static or dynamic experimental conditions are widely inconsistent. Between the lowest and the highest value for one and the same pathfinding instrument was a factor of about 123 when cyclic fatigue was assessed either under static or dynamic experimental conditions. Moreover, standard deviations of up to 30% have been reported. Environmental temperature has a 500% impact on the lifetime of instruments. In conclusion, fatigue resistance tests conducted under room temperature should be regarded as having little meaning and the scientific and clinical benefits of fatigue resistance tests are very limited. These data should be provided by the manufacturer of the instruments.