Radiographic evaluation of root canal fillings accomplished by undergraduate dental students

The purpose of this study was to evaluate the radiographic quality of root canal
fillings by fourth-, fifth-, and sixth-year undergraduate students at Tabriz Faculty of Dentistry
between 2006 and 2012. Methods and Materials: A total of 1183 root canal fillings in 620
teeth were evaluated by two investigators (and in case of disagreement by a third investigator)
regarding the presence or absence of under-fillings, over-fillings and perforations. For each
tooth, preoperative, working and postoperative radiographs were checked. The Pearson’s chisquare
test was used for statistical evaluation of the data. Inter-examiner agreement was
measured by Cohen’s kappa (k) values. The level of significance was set at 0.05. Results: Total
frequencies of over-filling, under-filling and perforation were 5.6%, 20.4% and 1.9%,
respectively. There were significant differences between frequencies of over- and under-fillings
(P<0.05). Unacceptable quality, under- and over-fillings were detected in 27.9% of 1183
evaluated canals. Conclusion: The technical quality of root canal therapies performed by
undergraduate dental students using step-back preparation and lateral compaction techniques
was unacceptable in almost one-fourth of the cases.