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Evaluation of a broken instrument removal training course for general dentistry residents
Kexian Xie1, Yuangao Li1, Xiao Wang1
1Department of Stomatology, Peking University Third Hospital, Beijing, China.
Introduction:
To help general dentistry residents better manage the intracanal broken instrument situation, we introduced a hands-on training course into the endodontic curriculum of a general dentistry residency programme.
Materials And Methods:
Thirty general dentistry residents and 30 residents with endodontic specialty training background in a general hospital served as the experimental group and reference group, respectively. The experimental group underwent a training course including a 30-min lecture and two hands-on sessions (2 h each). After the course, residents from both groups were asked to perform the instrument removal procedure on simulated root canals. Success rate, procedure time and canal volume change were compared between groups. Questionnaire results were also analysed.
Results:
All residents successfully managed to remove the broken instruments in the test. Procedure time was significantly longer for general dentistry residents (15.8 ± 5.7 min vs 13.7 ± 4.5 min, Mann-Whitney U test, p = .038). Canal volume change was significantly greater for general dentistry residents (8.53 ± 3.82 μl vs 5.94 ± 2.73 μl, independent-samples t-test, p = .004). In the questionnaires, trainees gave overall positive ratings for the course. The marginal homogeneity test on before and after scores of the questionnaire items showed the training helped the trainees to reduce the stress level associated with instrument breakage (p < .001). It also motivated the trainees to remove the broken instrument in some straightforward cases (p < .001).
Conclusion:
The broken instrument removal training course could help the general dentistry residents better manage the intracanal broken instrument situation.

