Evaluation of Technical Quality and Procedural Errors of Root Canal Treatment Performed by Undergraduate and Postgraduate Dental Students: A Retrospective Radiographic Analysis

Abstract

Aims: To assess and compare the technical radiographic quality of root canal fillings (RCF) and the

occurrence of procedural errors in the endodontic treatment performed by 5th grade undergraduate and

postgraduate students in the College of Dentistry/University of Baghdad- Baghdad- Iraq.

Materials and methods: Records and periapical radiographs of 216 and 143 root-filled teeth treated by 5th

year undergraduate and postgraduate students, respectively during 2018-2019 were collected. Periapical

radiographs of 35 (16.2%) and 15 (10.4%) teeth, respectively excluded because of inadequacy in the

radiographs. A final total periapical radiographs/records of 181 and 128 root-filled teeth were used to

evaluate the technical quality of the root fillings in 197 and 275 root canals treated by 5th year undergraduate

and postgraduate students, respectively. Outcome variables categorized as acceptable and not acceptable

quality depending on the absence/presence of overfilling, underfilling, voids in the fillings and the absence/

presence of ledges, root perforation, transportation, and fractured instruments. Chi-square and 2 sample z

tests were used for statistical analysis, significance level set at ?=0.05

Results: Acceptable RCF were in 49.3% and 63.3% of the canals treated by 5th year undergraduate and

postgraduate students, respectively with a significant difference between them (z=2.99, p<0.05). 55.1%

and 44.9% of RCF treated by undergraduate students were in anterior and premolars, respectively. 70.9%,

20.7% and 8.4% of RCF treated by postgraduate students were in molars, premolars and anterior teeth,

respectively. Significantly more voids, ledges were observed in RCF performed by undergraduate compared

to postgraduate students (z=4.6 and 2 respectively, p<0.05). In contrast, significantly more instrument

separations were observed in RCF treated by postgraduate compared to undergraduate students (z=2.09,

p<0.05). However, there was no significant difference in proportions of underfilling, overfilling, perforations,

transportation between the two academic levels.

Conclusion: Overall technical quality of RCF performed by postgraduates was better than that of 5th year

undergraduate students, however, improvement in preclinical and clinical training is needed.