Quality of Root Canal Fillings Performed by Undergraduate Students and the Related Factors on the Treatment Outcome: A 2- to 5-Year Follow-Up

Technical Quality of Root Fillings Performed by Undergraduate Dental Students in Single-Canal Teeth: A 10-Year Retrospective Study

OBJECTIVE

This study assessed the radiographic technical quality of root fillings in single-canal teeth performed over a decade (June 2013 to June 2023) by undergraduate dental students of the Federal University of Campina Grande.

METHODS

All teeth underwent chemomechanical preparation using Gates-Glidden drills and hand instrumentation with stainless steel files up to 1 mm short of the root apex. Apical expansion was performed with up to two or three instruments above the initial anatomical apical diameter. The canal was filled in the absence of signs and symptoms of infection using gutta-percha cones and Sealer 26 or MTA Fillapex. A post-filling radiograph was routinely taken to assess the quality of root filling and coronal restoration. An experienced researcher trained and calibrated an examiner to evaluate post-operative periapical radiographs considering root-filling length, lateral adaptation and taper using ImageJ 1.52q software. Root filling was satisfactory when reaching acceptable classifications for the three parameters. The chi-squared test compared tooth type, dental arch and pulpal diagnosis at a 5% significance level.

RESULTS

The study assessed 124 canals, showing 90 (72.6%) satisfactory root fillings. The sub-analysis of individual parameters demonstrated that 105 (84.7%) root fillings had acceptable length, 113 (91.1%) adapted well to lateral canal walls, and 109 (87.9%) had proper taper. Most cases occurred in maxillary teeth (n = 99), pulp necrosis was the most frequent pulpal diagnosis (n = 89), and root-filling quality showed no association with tooth type, dental arch or pulpal diagnosis.

CONCLUSION

The technical quality of root fillings in single-canal teeth treated by dental students was predominantly satisfactory.

Assessment of the quality of root canal fillings performed on extracted teeth by undergraduate dental students in a sample from Saudi Arabia

BACKGROUND

The educational process in the field of endodontics commences with preclinical exercises to enhance students' proficiency in cleaning, shaping, and performing root canal fillings. Therefore, this study aimed to radiographically evaluate the technical quality of root canal fillings performed by preclinical students on extracted teeth at the College of Dentistry, University of Ha'il, Saudi Arabia.

METHODS

A total of 788 extracted human teeth received root canal treatment by undergraduate students. The samples were then gathered and radiographically assessed using the three quality criteria of length, density, and taper. The category of root canal fillings was classified as either acceptable or unacceptable. The criteria for evaluating the acceptability of filling quality were defined based on the presence of adequate length, density, and taper. The effectiveness of root canal fillings was also evaluated in relation to the tooth type, sex, and treatment year. The agreement between the examiners was evaluated using Cohen's kappa test, and the relationship between the research variables was determined using the chi-squared test. The significance threshold was set at 0. 05.

RESULTS

The overall quality of root filling was determined to be satisfactory in 532 (67.5%) of 788 endodontically treated extracted teeth. The majority of the research sample (88.1%) had enough length, 89.6% had adequate density, and 86.4% had acceptable taper. The quality of anterior teeth was substantially better than that of posterior teeth (p < 0.001). Our findings showed that the quality of root canals was better in 2022 than it had been in earlier years (p = 0.001). The three RCT quality criteria differed significantly when compared between sexes (p = 0.002).

CONCLUSIONS

The quality of the root canal fillings completed by undergraduate students was rated as acceptable. The findings of the research suggest that the implementation of routine assessments to evaluate the technical competence of undergraduate dental students performing root canal treatments could provide significant insights into the efficacy of the curriculum requirements.

External root thermal analysis of three different obturation techniques

Background

The purpose of this study was to assess the external root surface thermal behavior when submitted to three different obturation techniques.

Material and Methods

Forty-five single-rooted premolars were selected, prepared and randomly divided into three groups according to the studied obturation techniques: lateral condensation (LC), single cone technique (SCT) and injectable thermoplasticized technique (IT). Each tooth was placed in a customized apparatus and connected to a thermocouple. A FLIR T650sc infrared thermal camera was used to assess root temperature in a room under controlled temperature and humidity. Temperature values were recorded using the thermal camera and thermocouples before, during and 30, 60, 90, 120, 150s after obturation. Shapiro-Wilk, QQ-plot, Levene's, ANOVA-three-way, Mauchly's sphericity, Box's M and Bonferroni tests were used to assess data. The significance level was set at 5%.

Results

Infrared assessment showed significant temperature changes between time intervals, obturation techniques and root thirds. Temperature increase was observed 30s after obturation for STL, LC and IT, followed by a gradual temperature decline, with temperature values similar to the initial temperature at 150s for LC and IT. SCT temperature values only returned to normal 60s after obturation in the apical third and 90s in the middle and cervical thirds. In all techniques, the temperature did not rise above the critical limit of 10°C.

Conclusions

All studied obturation techniques increased root surface temperature with IT showing the highest temperature increase. However, the temperature increase does not exceed the acceptable limits, not causing damage to the surrounding tissues. Key words:Endodontics, changes in body temperature, root canal filling, thermography.

A Comparative Evaluation of Endodontically Treated Root Canals Obturated Using Gutta-percha with Two Different Protocols: An In-vitro Study

OBJECTIVE

The aim of this article is to evaluate the quality of filling in endodontically treated root canals using the lateral condensation technique and modified lateral condensation technique.

MATERIALS AND METHODS

Thirty-two single-rooted teeth were divided into two groups that were assigned by simple randomization according to the filling technique. Once the endodontic treatment was performed, a periapical radiograph was taken to assess the quality according to the radiographic density and tomography was taken to evaluate the quality according to the tomographic volume of spaces, compared with the post-preparation biomechanical tomography. Finally, we performed a statistical analysis (Student's t-test) to evaluate whether there were differences between the types of filling.

RESULTS

Radiographic radiodensity was 182.89 ± 9.81 and 186.72 ± 6.97 HU for teeth treated with the lateral condensation technique and modified lateral condensation technique, respectively. The void volume was 3.75 ± 2.35 and 2.43 ± 1.18 mm³ for teeth treated with the lateral condensation technique and modified lateral condensation technique, respectively.

CONCLUSION

No significant differences were found between the techniques for both filling quality parameters.

Evaluation of new endodontic tooth models in clinical education from the perspective of students and demonstrators

BACKGROUND

The quality of root canal treatments performed by undergraduate students is often unsatisfactory questioning the current methods of teaching. Based on treatment errors made by students participating the endodontic courses at RWTH Aachen University (Germany), new radiopaque artificial root canal treatment models (DRSK RCT; incisor, premolar, molar) were designed and developed. The aim of the study was to evaluate these models by groups of students and demonstrators.

METHODS

A total number of 60 students and seven demonstrators from a single institution (RWTH Aachen) participated in this study. They performed endodontic treatments on either initial versions of the DRSK RCT or modified versions. The initial versions were evaluated by students (n = 25) and demonstrators (n = 7). The obtained questionnaire was conducted as 7-point Likert-Scale covering the topics material properties, feeling while performing exercises and perception of its closeness to reality via 19 items (students) and 21 items (demonstrators). According to the evaluations several alterations were applied to the DRSK RCT, the whole study was repeated and evaluated by different students (n = 35) and the same demonstrators (n = 7). Additionally, the demonstrators blindly evaluated the quality of root canal treatments performed by the students (n = 35) on the modified DRSK RCT. Comparisons between the initial versions and the modified versions were calculated using Chi-squared tests.

RESULTS

Students as well as demonstrators positively evaluated both variants of the DRSK RCT with especially high ratings in the overall evaluation. Students' rating of the pulp anatomy significantly increased from 5.4 ± 1.1 (mean ± SD) to 5.9 ± 0.9 (mean ± SD; p < 0.05) for the modified model. Likewise, students felt that the ability to flare root canals improved after alterations have been applied. Ratings significantly increased from 4.8 ± 1.6 (mean ± SD) to 5.6 ± 1.0 (mean ± SD; p < 0.05).

CONCLUSION

The results indicate that the DRSK RCT is a promising candidate to be used as an alternative to extracted teeth or as an additional tool for improving dental education. However, some limitations of our analysis have to be considered.