Quality of root canal fillings performed by undergraduate dental students on single-rooted teeth

Endodontic Procedural Errors and Associated Factors among Undergraduate Dental Students: A Cross-sectional Study

AIMS AND BACKGROUND

To assess the procedural errors committed by undergraduate students at RAK College of Dental Sciences, during root canal treatments and the factors associated with these errors.

MATERIALS AND METHODS

In this cross-sectional study, 180 self-administered questionnaires were distributed, each comprising 26 questions, among 4th and 5th-year students. Participants were requested to report their endodontic mishaps based on feedback from their supervisors. The questionnaire assessed the frequency and types of procedural errors, considering patient, operator, and tooth-related factors. Data were collected tabulated and analyzed using the Chi-square test.

RESULTS

A total of 124 root canal-treated teeth exhibiting iatrogenic errors done by students were assessed. Out of which, 53% were performed by 5th-year students, and 69% were conducted by female operators. About 62% of errors occurred in the upper teeth and 68% in the posterior teeth. The most prevalent errors during the rubber dam isolation step were soft tissue trauma (21%) and isolation leakage (20%), significantly associated with limited mouth opening, excessive salivation, and tooth malalignment (p < 0.05). Apical blockage (15%) emerged as the most frequent error during instrumentation phase, showing a significant association with canal dimension and curvature (p < 0.05). For access cavity and obturation phases, under-extended cavity (9%), and under-extended filling (11%) were the most reported errors, respectively.

CONCLUSION

Tooth isolation emerges as a particularly challenging aspect for dental students, particularly when dealing with patients exhibiting limited mouth opening and excessive salivation.

CLINICAL SIGNIFICANCE

Clinical instructors should caution the undergraduates about the heightened risk of endodontic procedural errors when dealing with patients exhibiting limited mouth opening, excessive salivation, tooth misalignment, and narrow canals. Addressing these challenges is crucial for enhancing the proficiency of undergraduate students in performing successful root canal treatments. How to cite this article: Elsayed MA, Islam MS, Saleh DR, et al. Endodontic Procedural Errors and Associated Factors among Undergraduate Dental Students: A Cross-sectional Study. J Contemp Dent Pract 2023;24(12):998-1007.

Assessing Confidence Levels in Endodontic Procedures Among Senior Undergraduate Dental Students at Qassim University, Saudi Arabia: A Cross-Sectional Observational Study

Background This study aimed to determine the confidence of senior dental students in Qassim University's undergraduate dentistry program in Saudi Arabia regarding their capacity to perform endodontic procedures. The study's objective was to pinpoint areas of weakness and offer suggestions for potential improvement of endodontic and clinical training for dental students. Methodology Using anonymous survey forms, 120 senior dental students were surveyed. Students' self-reported levels of confidence in performing various endodontic procedures, such as periapical radiographs, rubber dam placement, endodontically treated tooth restoration, anesthesia, broken instrument removal, and endodontic retreatment, were studied in this survey. A Likert-style rating scale of 1 to 5 was used in the survey, with 1 denoting high confidence and 5 denoting low confidence. Results The majority of senior dental students at Qassim University reported high levels of confidence in taking periapical radiographs, with 64.04% indicating a high level of confidence. The second most assured field was rubber dam installation, with 47.6% of students expressing high levels of assurance. Confidence levels were noticeably lower during more difficult procedures such as endodontic retreatment and the removal of broken instruments. While 12% of students expressed high confidence in endodontic retreatment, only 3.46% of students expressed high confidence in removing broken instruments. According to Pearson's correlation (r = 0.352, p = 0.001), there was a significant and favorable correlation between competency level and confidence in performing various endodontic procedure-related steps. Conclusions The study's findings suggest that senior dentistry students at Qassim University might benefit from additional training and assistance in some endodontic treatment areas. The lack of confidence displayed during more challenging procedures, such as the removal of broken instruments and endodontic retreatment, demonstrates the need for additional training and supervision in such cases. The results of this study may be useful for educators in other dental colleges who wish to consider developing new teaching techniques, utilizing simulators and digital learning tools, and increasing opportunities for hands-on training and supervision to improve dental students' self-confidence and skills.

Cone-Beam Computed Tomography Assessment of Quality of Endodontic Treatment and Prevalence of Procedural Errors in Mandibular Molars

Objectives

This study assessed the quality of endodontic treatment and the prevalence of procedural errors in permanent mandibular molars using cone-beam computed tomography (CBCT).

Materials and Methods

This cross-sectional study was conducted on 328 CBCT scans (182 females and 146 males) of endodontically treated mandibular molars retrieved from the archives of two radiology centers in Ardabil city, Iran, in 2019. Mandibular molars were evaluated on sagittal, coronal, and axial sections regarding obturation length, obturation density (voids), missed canals, broken instruments, apical perforation, strip perforation, ledge formation, transportation, root fracture, root resorption, and periapical lesions by a senior dental student under the supervision of an oral and maxillofacial radiologist and an endodontist. Differences between the frequency of procedural errors and tooth type and gender were analyzed by the chi-square test.

Results

The frequency of underfilling, missed canals, overfilling, voids, apical perforation, transportation, ledge formation, broken instruments, root fracture, strip perforation, root resorption, and periapical lesions was 34.8%, 17.4%, 16.8%, 14.3%, 7.3%, 6.1%, 4.3%, 3%, 1.2%, 0.6%, 5.5%, and 46%, respectively. The frequency of root fracture was significantly higher in females than in males (P < 0.05). The prevalence of underfilling was the highest in right second molars (47.2%), followed by right first molars, left second molars, and left first molars (P < 0.005). The frequency of transportation was maximum in right first molars (10%), followed by right second molars, left first molars, and left second molars (P < 0.04).

Conclusion

Underfilling, missed canals, and overfilling were the most prevalent procedural errors in mandibular molars in our study population.

Quality of root canal treatment performed by undergraduate students using nickel-titanium reciprocating versus hand instruments

PURPOSE

To compare the technical quality of root canal treatment (RCT) depending on the incidence of procedural errors performed by undergraduate students using nickel-titanium reciprocating and conventional hand instrumentation techniques, and to assess the impact of case difficulty and localization of the teeth (maxillary or mandibular molars).

METHODS

Dental records and periapical radiographs of molars that were treated with either hand or reciprocating WaveOne (WO) instruments were evaluated retrospectively. The technical quality of RCTs, the incidence of ledge formation, perforation, instrument fracture, overinstrumentation, underfilling, overfilling, inadequate root canal filling, and the effects of case difficulty and tooth localization were compared using the chi-square test with a significance of 5% (α = 0.05).

RESULTS

While overinstrumentation was more frequent in the WO group (247 teeth), the incidence of inadequate root canal fillings was higher in the hand instrumentation group (245 teeth) (p < 0.01). No significant difference was observed in the incidence of other procedural errors (p > 0.05). The number of teeth with acceptable technical quality in preparation and obturation was 172 (69.6%) in the WO group, whereas it was 142 (58%) in the hand instrumentation group, presenting a significant difference between the instrumentation techniques (p < 0.01). Higher technical quality rates were observed with WO instrumentation in the high difficulty category and in maxillary teeth (p < 0.01).

CONCLUSION

Higher technical quality in preparation and obturation can be achieved with WO reciprocating instruments and file-matched greater tapered gutta-percha cones. No significant difference was observed between the groups in the incidence of procedural errors except for overinstrumentation and insufficient root canal filling. WO instrumentation and obturation with file-matched greater tapered gutta-percha cones provided better technical quality in the high difficulty category and in maxillary teeth.

An Audit of the Technical Quality and Iatrogenic Errors of Root Canal Treatment by Undergraduate Dental Students at the University of Sharjah

OBJECTIVES

 The aim of this study was to determine the technical quality of root canal fillings and the presence of iatrogenic errors in the cases treated by undergraduate dental students using radiographic images.

MATERIALS AND METHODS

 This study included 480 root-filled teeth, which were evaluated using intraoral periapical radiographic images. The technical quality of obturation was assessed by observing the length, density, and taperness of the root filling. Ledges, apical transportation, fractured instruments, zipping, and root perforation were recorded as iatrogenic errors. Teeth were classified as acceptable if the technical parameters were adequate and there were no iatrogenic errors.

STATISTICAL ANALYSIS

 Data were statistically analyzed using Pearson's chi-squared test.

RESULTS

 The quality of root filling was acceptable in 183 of the 480 teeth. The rate of acceptable quality was higher for the teeth treated by 4th-year students (41.9%) than for those treated by 5th-year students (27.4%; p = 0.004). Length and taperness were adequate in more of the patients treated by the 4th-year students (p<0.05). There was a significant difference in the incidence of ledge formation and apical transportation in relation to the student's level (p<0.05).

CONCLUSIONS

 The technical quality of root fillings performed without iatrogenic errors by undergraduate dental students was declared acceptable in 38.1% of the assessed teeth. There was a noticeable difference in the quality of root canal treatment between the 4th- and 5th-year students.

CLINICAL RELEVANCE

 The findings demonstrate that periodic assessment of the technical quality of root filling performed by undergraduate dental students provides feedback on curriculum standards.

Retrospective audit for quality assessment of root fillings performed by undergraduate dental students in clinics

Objectives

To evaluate the technical quality of root canal obturations performed by undergraduate students.

Methods

The records of 347 patients who underwent endodontic treatment by undergraduate students of Qassim University between 2018 and 2020 were assessed using standardised criteria based on obturation length, density and taper. All teeth that received primary endodontic treatment and had post-obturation periapical radiographs depicting the entire radicular length and the 2–3-mm periradicular area were included in the study.

Results

A total of 653 canals of 397 teeth were evaluated. The maxillary central incisor was the most commonly assessed tooth (15.1%). Overall, 80.2% of the evaluated canals were deemed acceptable based on all three assessment criteria. Maxillary teeth had significantly better obturation quality than the mandibular teeth. The mesio-lingual canal had the lowest quality in all three criteria.

Conclusions

The technical quality of root canal obturations performed by undergraduate students in Qassim University was acceptable in the majority of the evaluated cases. Among the evaluated parameters of obturation quality, length control was the most frequently observed deficiency. Additional measures are therefore required to improve the quality of the obturation length.

The effect of COVID-19 pandemic on final year dental students' self-confidence level in performing clinical procedures

BACKGROUND

The outbreak of COVID-19 pandemic in 2020 has dramatically changed teaching approach in dental schools due to the switch to distance learning and the lack of practice training in direct contact with patients with possible impact on clinical skills of students. The aim of the study was to assess the level of the 2020 final year dental students' self-confidence in performing different dental procedures through specially designed questionnaire and compare it to self-confidence of the 2019 final year students.

MATERIALS AND METHODS

An anonymous questionnaire consisting of 40 questions regarding self-confidence level in performing 40 different dental procedures and based on five points Likert-like scale was distributed during November 2020 to final year dental students whose studies were disrupted by the COVID-19 pandemic lockdown in one semester. The study group comprised their answers. The comparison was done with the control group that consisted of students' answers on the same questionnaire from previous 2019 year conducted as a part of regular internal educational evaluation.

RESULTS

Response rate was 74.2% in study group and 89.3% in control group. Mean level of self-confidence reported by 115 students in study group was significantly lower than that reported by 100 students in control group (3.28±1.08 vs. 3.58±0.88, respectively) and the distribution of self-confidence scores were different in observed groups. Graduates from study group felt less confident than those from control in 8 clinical skills.

CONCLUSION

Abrupt changes in teaching modalities caused by COVID-19 pandemic had significant impact on final year dental students' self-confidence indicating additional educational needs in postgraduate period.

Formative feedback generation in a VR-based dental surgical skill training simulator

Fine motor skill is indispensable for a dentist. As in many other medical fields of study, the traditional surgical master-apprentice model is widely adopted in dental education. Recently, virtual reality (VR) simulators have been employed as supplementary components to the traditional skill-training curriculum, and numerous dental VR systems have been developed academically and commercially. However, the full promise of such systems has yet to be realized due to the lack of sufficient support for formative feedback. Without such a mechanism, evaluation still demands dedicated time of experts in scarce supply. To fill the gap of formative assessment using VR simulators in skill training in dentistry, we present a framework to objectively assess the surgical skill and generate formative feedback automatically. VR simulators enable collecting detailed data on relevant metrics throughout a procedure. Our approach to formative feedback is to correlate procedure metrics with the procedure outcome to identify the portions of a procedure that need to be improved. Specifically, for the errors in the outcome, the responsible portions of the procedure are identified by using the location of the error. Tutoring formative feedback is provided using the video modality. The effectiveness of the feedback system is evaluated with dental students using randomized controlled trials. The findings show the feedback mechanisms to be effective and to have the potential to be used as valuable supplemental training resources.

The value of assessing case difficulty and its effect on endodontic iatrogenic errors: a retrospective cross-sectional study

The American Association of Endodontists (AAE) released a case difficulty assessment form to help general dentists and students treat cases within their expertise or refer advanced cases to reduce the risk of iatrogenic errors. The purpose of this study was to determine the incidence of iatrogenic complications after the use of the case difficulty assessment form. Arandom sample of 1000 cases that received root canal treatment in undergraduate clinics during the academicyear (2016–2017) was selected. Case difficulty assessment was made for each case before treatment onset. Once the case was approved for treatment in the undergraduate clinics, the endodontic treatments were performed following the standard procedure the endodontic department of the Dentistry School of King Abdulaziz University mandates. Digital radiographs were obtained during routine root canal treatment and were evaluated by four observers to detect any iatrogenic errors, after which the data were analyzed statistically. Iatrogenic errors were correlated significantly with case difficulty (p= 0.003), and were detected in 22.1% of all teeth treated in the undergraduate clinics. Underfilling accounted for the highestpercent of errors detected (8.4%), followed by ledge formation (4.2%). Molar teeth had the highest frequency of errors, and mesio-buccal roots of maxillary molars showed the highest percentage of errors. The AAE developed asignificantly useful tool to determine the difficulty of each case treated in undergraduate clinics, and following their recommendations will minimize the risk of iatrogenic errors.

An audit of root canal filling quality performed by undergraduate pre-clinical dental students, Yemen

BACKGROUND

Dental students are future dentists. Continuous assessment and improving of the educational curricula will ensure excellent academic performance of dental students and thus providing the community with the best treatment modalities. The aim of this study was to evaluate the root canal filling quality performed in extracted teeth by preclinical undergraduate Yemeni dental students.

METHODS

Root canal treatment was performed by undergraduate preclinical dental students on 331 extracted human teeth including 741 roots. The teeth were then collected and evaluated radiographically based on three criteria of quality (length, density, and taper). Cohen's Kappa test was used to assess the agreement between the examiners and Chi-squared test was used for the association between the study variables. The level of significant was set at α < 0.05.

RESULTS

The results of the study revealed that the overall quality of roots canals fillings was poor. However, more than half of the study sample (53.4%) had adequate length, 13.1% had adequate density, and 14.2% had adequate taper. Anterior as well as single-rooted teeth had significantly better quality than posterior and multi-rooted teeth, respectively. The root canal fillings quality mandibular teeth was better than of maxillary teeth with no significant difference (P > 0.05).

CONCLUSION

The findings of the study emphasize the need of improving the endodontic course in the preclinical level and more advanced techniques and instruments should be incorporated.

Novel endodontic sealer with dual strategies of dimethylaminohexadecyl methacrylate and nanoparticles of silver to inhibit root canal biofilms

OBJECTIVE

Endodontic treatment failures and recontamination remain a major challenge. The objectives of this study were to: (1) develop a new root canal sealer with potent and long-lasting antibiofilm effects using dimethylaminohexadecyl methacrylate (DMAHDM) and nanoparticles of silver (NAg); (2) determine the effects of incorporating DMAHDM and NAg each alone versus in combination on biofilm-inhibition efficacy; and (3) determine the effects on sealer paste flow, film thickness and sealing ability, compared to a commercial control sealer.

METHODS

Dual-cure endodontic sealers were formulated using DMAHDM mass fractions of 0%, 2.5% and 5%, and NAg mass fractions of 0.05%, 0.1% and 0.15%. The sealing ability of the sealers was measured using linear dye penetration method. Colony-forming units (CFU), live/dead assay, and polysaccharide production of biofilms grown on sealers were determined.

RESULTS

The sealer with 5% DMAHDM and 0.15% NAg yielded a flow of (22.18 ± 0.58) which was within the range of ISO recommendations and not statistically different from AH Plus control (23.3 ± 0.84) (p > 0.05). Incorporating DMAHDM and NAg did not negatively affect the film thickness and sealing properties (p > 0.05). The sealer with 5% DMAHDM and 0.15% NAg greatly reduced polysaccharide production by the biofilms, and decreased the biofilm CFU by nearly 6 orders of magnitude, compared to AH Plus and experimental controls (p < 0.05).

SIGNIFICANCE

A therapeutic root canal sealer was developed using 5% DMAHDM with biofilm-inhibition through contact-mediated mechanisms, plus 0.15% of NAg to release silver ions into the complex and difficult-to-reach root canal environment. The novel root canal sealer exerted potent antibiofilm effects and reduced biofilm CFU by 6 orders of magnitude without compromising sealer flow, film thickness and sealing ability. This method provided a promising approach to inhibit endodontic biofilms and prevent recurrent endodontic infections.

Pre-clinical endodontic education outcomes between artificial versus extracted natural teeth: a systematic review

AIM

To compare the educational outcomes using artificial teeth versus extracted teeth for pre-clinical endodontic training.

DATA SOURCES

Literature searches of PubMed, Scopus, Cochrane Library, Trip Database, Web of Science and Open Grey databases were conducted from their inception until November 2018 with no language restriction. Hand searching of most likely relevant journals was performed. The review followed the PRISMA guidelines.

STUDY ELIGIBILITY CRITERIA, PARTICIPANTS AND INTERVENTIONS

Studies that compared pre-clinical endodontic training using extracted teeth and artificial teeth were included.

STUDY APPRAISAL AND SYNTHESIS METHODS

The quality of included studies was appraised by Joanna Briggs Institute Critical Appraisal tools. The findings were tabulated and summarized according to their outcomes with distinct narrative syntheses.

RESULTS

Five studies were included. The component studies included 359 operators in total, mainly consisting of undergraduate students (97%, n = 349) and 10 endodontists (3%). Forty-seven per cent (n = 170) operated on artificial teeth only, whilst 19% (n = 67) worked primarily on extracted teeth, with the final treatment outcome being evaluated by independent observers using objective criteria. Operators in two studies (34%, n = 122) used both artificial teeth and ET and compared their experiences in surveys. Regarding technical outcomes, no significant differences between training with artificial teeth and extracted teeth were found, but the performance tended to be better in artificial teeth than extracted teeth. Operators trained solely on artificial teeth appeared to be adequately educated for subsequent root canal treatment (RCT) in the clinical setting.

LIMITATIONS

Due to the scarcity of research on the topic overall, and the methodological variation between the studies, it was not possible to perform a quantitative analysis (meta-analysis).

CONCLUSIONS AND IMPLICATIONS OF KEY FINDINGS

Based on the available evidence, the use of artificial teeth for pre-clinical endodontic training achieved similar educational outcomes compared to extracted teeth. However, the experiences reported by the operators diverged. Further studies assessing other artificial teeth available in the market testing other RCT procedures are necessary.

Novel bioactive root canal sealer with antibiofilm and remineralization properties

OBJECTIVES

(1) To develop a novel bioactive root canal sealer with antibiofilm and remineralization properties using dimethylaminohexadecyl methacrylate (DMAHDM) and nanoparticles of amorphous calcium phosphate (NACP); (2) investigate the effects on E. faecalis biofilm inhibition, sealer flow and sealing ability, compared with an epoxy-resin-based sealer AH Plus; and (3) investigate the calcium (Ca) and phosphate (P) ion release from the sealers.

METHODS

A series of dual-cure endodontic sealers were formulated with DMAHDM and NACP at 5% and 20% by mass, respectively. Flow properties and sealing ability of the sealers were measured. Colony-forming units (CFU), live/dead assay, and polysaccharide production of biofilms on sealers were determined. Ca and P ion releases from the sealers were measured.

RESULTS

The new sealer containing 20% NACP and 5% DMAHDM yielded a paste flow of (28.99 ± 0.69) mm, within the range of ISO recommendations. The sealing properties of the sealer with 5% DMAHDM and 20% NACP were similar to a commercial control (p > 0.05). The sealer with DMAHDM decreased E. faecalis biofilm CFU by more than 4 orders of magnitude, compared to AH plus and experimental controls. The sealer with 20% NACP and 5% DMAHDM had relatively high levels of Ca and P ion release necessary for remineralization.

CONCLUSIONS

A new bioactive endodontic sealer was developed with strong antibiofilm activity against E. faecalis biofilms and high levels of Ca and P ion release for remineralization, without compromising the paste flow and sealing properties.

CLINICAL SIGNIFICANCE

The bioactive antibacterial and remineralizing root canal sealer is promising to inhibit E. faecalis biofilms to prevent endodontic treatment failure and secondary endodontic infections, while releasing high levels of Ca and P ions that could remineralize and strengthen the tooth structures and potentially prevent future root fractures and teeth extractions.

Outcome of Initial Endodontic Treatment Performed, by One Specialist, in 122 Tunisian Patients: A Retrospective Study

Objective

To assess the 6- to 24-month outcome of endodontic treatments performed, by one specialist, and to identify prognostic factors that may influence initial endodontic treatment outcome (IETO).

Methods

One hundred and forty-six patients out of 163 were included. A number of 201 teeth were endodontically treated, and an overall number of 408 canals were obturated. Of these, 165 teeth received initial endodontic treatment (IET). The criteria of the European Society of Endodontology were used to assess the IETO. The level of significance was set at p < 0.05%.

Results

Apical periodontitis (AP) was present in 42.5% of all cases, with a PAI >3 in 28.5%. The success rate (SR) was 91.5%. It was significantly higher in vital teeth (97%) than in devital teeth (87.7%) (p=0.04); however, a lower SR was recorded in teeth with AP (p=0.02). The lesion healed in 60 teeth (85.7%), decreased in size in 4 teeth (5.7%), and increased in size in 6 teeth (8.5%). A higher SR was obtained when a permanent restoration was present (94%) than absent (68.7%) (p=0.005).

Conclusion

Within the limitations of the study, pulp and periapical status and permanent restoration are found to be strong outcome predictors.

Clinical audit training improves undergraduates' performance in root canal therapy

AIM

To evaluate the effectiveness of clinical audit-feedback cycle as an educational tool in improving the technical quality of root canal therapy (RCT) and compliance with record keeping performed by dental undergraduates.

METHODS

Clinical audit learning was introduced in Year 3 of a 5-year curriculum for dental undergraduates. During classroom activities, students were briefed on clinical audit, selected their audit topics in groups of 5 or 6 students, and prepared and presented their audit protocols. One chosen topic was RCT, in which 3 different cohorts of Year 3 students conducted retrospective audits of patients' records in 2012, 2014 and 2015 for their compliance with recommended record keeping criteria and their performance in RCT. Students were trained by and calibrated against an endodontist (κ ≥ 0.8). After each audit, the findings were reported in class, and recommendations were made for improvement in performance of RCT and record keeping. Students' compliance with published guidelines was presented and their RCT performances in each year were compared using the chi-square test.

RESULTS

Overall compliance with of record keeping guidelines was 44.1% in 2012, 79.6% in 2014 and 94.6% in 2015 (P = .001). In the 2012 audit, acceptable extension, condensation and the absence of mishap were observed in 72.4, 75.7% and 91.5%; in the 2014 audit, 95.1%, 64.8% and 51.4%; and in 2015 audit, 96.4%, 82.1% and 92.8% of cases, respectively. In 2015, 76.8% of root canal fillings met all 3 technical quality criteria when compared to 48.6% in 2014 and 44.7% in 2012 (P = .001).

CONCLUSION

Clinical audit-feedback cycle is an effective educational tool for improving dental undergraduates' compliance with record keeping and performance in the technical quality of RCT.

Radiographic Assessment of the Quality of Root Canal Fillings Performed by Senior Dental Students

Objective:

To evaluate the radiographic technical quality of root canal fillings performed by senior dental students at Alfarabi colleges for dentistry, Kingdom of Saudi Arabia.

Methods:

Radiographic assessment was conducted for 246 teeth (390 root canals) endodontically treated by senior dental students to evaluate the quality of root canal fillings. Three criteria were evaluated to assess the technical quality of root canal fillings: length, density, and taper. The root canal filling was considered acceptable if it had an adequate length with no voids and consistent taper from the orifice to the apex. Statistical analysis was conducted using Kruskal–Wallis, Mann–Whitney, and chi-square tests (P=0.05).

Results:

Acceptable root canal fillings were detected in 127 (32.6%) patients. The frequency of an acceptable root canal filling was the highest for the upper anterior teeth (40%). There were significant differences in the length and density among the types of teeth (P<0.05). However, there was no significant difference in the taper among the types of teeth (P>0.05).

Conclusion:

The quality of root canal fillings performed by senior undergraduate dental students at AlFarabi colleges for dentistry was acceptable in 32.6% of patients. This outcome enhanced the poor performance of undergraduate dental students in the area of endodontics.

Is it cost-beneficial to society? Measuring the economic worth of dental residency training

This study estimated whether continued programming of a highly specialized four-year dentistry residency training in Saudi Arabia was cost-beneficial. We utilized a purposive sampling to administer a survey to trainees in major cities. Additionally, we used publically available market information about general practitioners. We employed Benefit-Cost Analysis accounting approach as a conceptual framework. Using general practitioners as the base category, we grouped overall social analytical perspectives into resident trainees and rest of society. The residency program was cost-beneficial to trainees, realizing an estimated return of SR 4.07 per SR 1 invested. The overall societal return was SR 0.98 per SR 1 invested, slightly shy of a bang for the buck, in part because the public sector largely runs the training. Benefits included increased earnings and enhanced restorative dentistry skills accruing to trainees; increased charitable contributions and programming-related payments accruing to programs and the public; and practice-related payments accruing to governmental, professional, and insurance agencies. Rest of society, notably government underwrote much of the cost of programming. A sensitivity analysis revealed the results were robust to uncertainties in the data and estimation. Our findings offer evidence to evaluate whether continued residency training is cost-beneficial to trainees and potentially to overall society.

Method of teaching undergraduate students to perform root canal treatment: It's influence on the quality of root fillings

INTRODUCTION

This study aimed to assess whether the method of teaching endodontology influenced the quality of root fillings made by undergraduate students.

MATERIALS AND METHODS

The method of teaching endodontology at our institution was revised. Changes concerned: the programme (ie method of clinical training and summative assessment), and the supervision whilst performing root canal treatment on patients. An intermediate cohort (N=91) comprised partly students attending the former programme (involving patients) and partly students attending the revised programme (without patients). After succeeding in the summative assessment, the quality of the first root filling made by the student in a patient under supervision of either a general dental practitioner or an endodontist was evaluated according to pre-determined criteria. Data were analysed using Cohen's Kappa, Chi-square, Fisher's exact, Mann-Whitney and Kruskal-Wallis tests.

RESULTS

Sixty-two per cent (47 of 76) of root fillings made by students who attended the revised programme were of good quality, in comparison with 47% (seven of 15) of those made by students who attended the former programme (P=.274). Less complex treatments had better quality root fillings if students were supervised by endodontists (88% (14 of 16) good quality) than supervised by general dental practitioners (59% (22 of 37) good quality) (P=.045). Complex treatments did not differ in quality of root fillings for the supervision types (P=.825).

CONCLUSION

The quality of root fillings made by students who attended the revised programme seems at least as high as that of those who attended the former programme. Higher quality root fillings might be obtained under supervision of endodontists than under supervision of general dental practitioners.

Technical Quality of Root Canal Treatment Performed by Undergraduate Clinical Students of Isfahan Dental School

Introduction:

The aim of the present study was to evaluate the radiographic quality of RCTs performed by undergraduate clinical students of Dental School of Isfahan University of Medical Sciences.

Methods and Materials:

In this cross sectional study, records and periapical radiographs of 1200 root filled teeth were randomly selected from the records of patients who had received RCTs in Dental School of Isfahan University of Medical Sciences from 2013 to 2015. After excluding 416 records, the final sample consisted of 784 root-treated teeth (1674 root canals). Two variables including the length and the density of the root fillings were examined. Moreover, the presence of ledge, foramen perforation, root perforation and fractured instruments were also evaluated as procedural errors. Descriptive statistics were used for expressing the frequencies of criteria and chi square test was used for comparing tooth types, tooth locations and academic level of students (P<0.05).

Results:

The frequency of root canals with acceptable filling was 54.1%. Overfilling was found in 11% of root canals, underfilling in 8.3% and inadequate density in 34.6%. No significant difference was found between the frequency of acceptable root fillings in the maxilla and mandible (P=0.072). More acceptable fillings were found in the root canals of premolars (61.3%) than molars (51.3%) (P=0.001). The frequency of procedural errors was 18.6%. Ledge was found in 12.5% of root canals, foramen perforation in 2%, root perforation in 2.4% and fractured instrument in 2%. Procedural errors were more frequent in the root canals of molars (22.5%) than the anterior teeth (12.3%) (P=0.003) and the premolars (9.5%) (P<0.001).

Conclusion:

Technical quality of RCTs performed by clinical students was not satisfactory and incidence of procedural errors was considerable.

Evaluation of complications of root canal treatment performed by undergraduate dental students

This study evaluated the technical quality of root canal treatment (RCT) and detected iatrogenic errors in an undergraduate dental clinic at the College of Dentistry, Taibah University, Saudi Arabia. Dental records of 280 patients who received RCT between 2013 and 2016 undertaken by dental students were investigated by retrospective chart review. Root canal obturation was evaluated on the basis of the length of obturation being ≤2 mm from the radiographic apex, with uniform radiodensity and good adaptation to root canal walls. Inadequate root canal obturation included cases containing procedural errors such as furcal perforation, ledge, canal transportation, strip perforation, root perforation, instrument separation, voids in the obturation, or underfilling or overfilling of the obturation. In 193 (68.9%) teeth, RCT was adequate and without procedural errors. However, in 87 (31.1%) teeth, RCT was inadequate and contained procedural errors. The frequency of procedural errors in the entire sample was 31.1% as follows: underfilling, 49.9%; overfilling, 24.1%; voids, 12.6%; broken instruments, 9.2%; apical perforation, 2.3%; and root canal transportation, 2.3%. There were no significant differences (p > 0.05) in the type or frequency of procedural errors between the fourth- and fifth-year students. Lower molars (43.1%) and upper incisors (19.2%) exhibited the highest and lowest frequencies of procedural errors, respectively. The technical quality of RCT performed by undergraduate dental students was classified as ‘adequate’ in 68.9% of the cases. There is a need for improvement in the training of students at the preclinical and clinical levels.

Influence of Method of Teaching Endodontics on the Self-Efficacy and Self-Perceived Competence of Undergraduate Dental Students

Objective:

This study assessed whether self-efficacy and the self-perceived competence of undergraduate dental students had been influenced by the method of teaching endodontics.

Methods:

Certain modules of the undergraduate endodontic programme at the Academic Centre for Dentistry Amsterdam (ACTA) including the tutorials, the clinical training and the assessment were revised. The self-efficacy and self-perceived competence close to graduation of an intermediate cohort of 24 students who attended all or some of the former modules or the revised modules were assessed. Additionally, the performance of students in performing root canal treatments was assessed according to predetermined criteria. Data were analysed using Cohen’s Kappa, Cronbach’s Alpha, Mann-Whitney and T-tests.

Results:

Self-efficacy and the self-perceived competence of students who followed the former modules of clinical training and assessment were similar to those of students who followed the revised modules. The revised module with higher number of tutorials increased students’ self-perceived competence, but did not influence their self-efficacy statistically significantly. Not the entire number, but the number of root canal treatments performed under supervision of endodontists was related with an increase in students’ self-efficacy and self-perceived competence. The performance of students in performing root canal tretaments was not statistically significantly related to their self-efficacy and self-perceived competence.

Conclusion:

Among the modules and their components assessed in the present study, only the number of tutorials and the number of root canal treatments performed under supervision of endodontists influenced the self-efficacy and the self-perceived competence of students.

Technical quality of root canal treatment performed by undergraduate students using hand instrumentation: a meta-analysis

The technical quality of root canal treatment (RCT) may impact on the outcome. The quality of education received during undergraduate school may be linked to the quality of treatment provided in general dental practice. In this context, the aim of this systematic review was to answer the following focused questions: (i) What is the frequency of acceptable technical quality of root fillings, assessed radiographically, performed by undergraduate students? (ii) What are the most common errors assessed radiographically and reported in these treatments? For this purpose, articles that evaluated the quality of root fillings performed by undergraduate students were selected. Data were collected based on predetermined criteria. The key features from the included studies were extracted. GRADE-tool assessed the quality of the evidence. MAStARI evaluated the methodological quality, and a meta-analysis on all studies was conducted. At the end of the screening, 24 articles were identified. Overall frequency of acceptable technical quality of root fillings was 48%. From this total, 52% related to anterior teeth, 49% to premolars and 26% to molars. The main procedural errors reported were ledge formation, furcation perforation, apical transportation and apical perforation. The heterogeneity amongst the studies was high (84-99%). Five studies had a high risk of bias, eight had a moderate risk, and 11 had low risk. The overall quality of evidence identified was very low. The conclusion was that technical quality of root fillings performed by undergraduate students is low, which may reveal that endodontic education has limited achievement at undergraduate level. A plan to improve the quality of root fillings, and by extrapolation the overall quality of root canal treatment, should be discussed by the staff responsible for endodontic education and training.

An audit on technical quality of root fillings performed by undergraduate students

AIM

To evaluate radiographically the technical quality of root fillings performed by undergraduate dental students and to assess whether students were exposed to an appropriate endodontic case mix during their clinical training.

METHODOLOGY

A retrospective audit was undertaken evaluating the clinical records of patients who underwent endodontic procedures during the period from September 2015 to June 2016 in the Dental School at Queen's University Belfast, UK. Two final-year dental students were trained and calibrated to evaluate postoperative intra-oral periapical radiographs of completed root canal treatments using specific assessment criteria. Data were presented as frequencies, percentage and mean ± standard deviation (SD). Comparisons of treatment outcomes between groups (posterior and anterior teeth) were calculated using Fisher's exact test, and the level of significance was set at P < 0.05. Intra- and interexaminer reproducibility was assessed by Kappa statistics.

RESULTS

A total of 222 teeth and 381 canals were assessed, and of those, 253 (66%) of the root fillings were found to be acceptable in all the assessment parameters, namely taper, length and lateral adaptation of the root filling. Subanalysis of individual root filling parameters revealed that 372 canals (97%) exhibited good taper, and 275 canals (72%) were considered to be of an appropriate length, with 89 canals (23%) found to be underfilled and 17 canals (5%) overfilled. Overall 346 (91%) of canals had good lateral condensation. Students treated both single and multirooted teeth, and there was no significant association between tooth type and the quality of root filling provided (P > 0.05).

CONCLUSIONS

In the majority of the teeth treated by undergraduate students at Queen's University Belfast, the technical quality of the root filling was acceptable and students were exposed to an appropriate case mix for endodontic training.

A re-audit of the technical quality of undergraduate root canal treatment after the introduction of new technology and teaching practices

AIM

To revaluate through re-audit the technical quality of undergraduate nonsurgical root canal treatment (RCTx) in a dental teaching hospital as a result of recommended changes to teaching practices.

METHODOLOGY

The technical quality of undergraduate RCTx was evaluated radiographically after educational changes and the mandatory introduction of new technologies (nickel-titanium files, apex locators, greater taper gutta-percha points) in 182 root canals. Evaluation was based on four criteria: presence of voids, root canal filling termination (0-2 mm of radiographic apex), all roots filled and the prepared canal contained the original anatomy. Chi-squared analysis was used to determine statistically significant improvements in quality between the respective audits (P < 0.05).

RESULTS

Twenty-three of the 40 canals in single-rooted teeth (57.5%) and 68 of the 129 (52.7%) canals in multirooted teeth analysed had an acceptable root filling. This compared with 48% of canals in single-rooted teeth and 38% of canals in multirooted teeth in the original audit. Specifically, the frequency of root canal voids and unsatisfactory apical root filling termination were reduced in multirooted teeth by 23% and 14% and in single-rooted teeth by 11% and 12%, respectively, compared with the original audit. When multirooted teeth were taken as one unit, 45.2% were considered to be acceptable, significantly better than the 18.8% multirooted teeth in the original audit (P = 0.042). Deviations from the canal anatomy on radiographic examination were rare findings in both audits.

CONCLUSIONS

Changes to endodontic teaching practices significantly improved the technical standards of undergraduate root filling in multirooted teeth. The regular auditing of undergraduate teaching practice is necessary to inform current teaching, instigate change and improve standards.

Preclinical endodontic teaching. A survey of Saudi dental schools

Objectives:

To provide an overview of the general curricula in preclinical endodontic training from 6 established dental schools in Saudi Arabia.

Methods:

This study was conducted in January 2014 including only schools that had more than 2 groups of student graduates prior to the study. We included 2 dental schools from the Central region, one from Qassim region, one from the Makkah region (west), one from Abha region (south west), and one from the eastern region. An internet-based questionnaire was sent to the course directors of preclinical endodontics department of the 6 schools. The survey comprised 20 questions that examined various aspects of preclinical endodontics.

Results:

It was demonstrated that a significant number of faculty members had Doctor of Philosophy (PhD) degrees (n=21), Master’s degrees (n=15), and Saudi board certifications (n=8). We determined that the faculty to student ratio varied from 2:1 to 8: 1 among the colleges. The participating dental schools were found to teach the Step Back, as well as the Step Down techniques for root canal preparation. Five of the 6 schools implemented the use of nickel titanium rotary instruments. All dental schools predominantly used radiographs as the means of the working length determination.

Conclusion:

The curriculum for preclinical endodontics in Saudi Arabia is comparable to that followed in most European countries. A more comprehensive survey is needed that would involve more schools to formulate generalized guidelines for preclinical endodontic training in Saudi Arabia.

Technical quality assessment of root canal treatment performed by preclinical dental students at Taibah University, KSA

Objectives

The aim of this study was to evaluate the technical quality of root canal treatment (RCT) performed by preclinical undergraduate dental students at the Dental College of Taibah University KSA.

Methods

In this study, 259 extracted teeth were treated endodontically by preclinical students of the College of Dentistry, Taibah University, KSA, from 2013 to 2015. The evaluation criteria were root canal obturation length, root canal obturation density (homogeneity), and root canal obturation taper. A specific score (0, 1, or 2) was assigned to each parameter.

Results

Of 259 endodontically extracted teeth, 138 (53.3%) had RCT of unacceptable technical quality, 42 (16.2%) had treatment of slightly acceptable technical quality, 50 (19.3%) had treatment of acceptable technical quality, and 29 (11.2%) teeth had RCT of perfectly acceptable technical quality. There were no significant differences (p > 0.05) in the technical quality of root canal obturation among types of teeth.

Conclusion

The results of this study showed that there were varied levels of technical quality of root canal treatment performed by preclinical undergraduate dental students, and the outcome varied between unacceptable, slightly acceptable, acceptable, and perfectly acceptable. The unacceptable cases were the most common, representing more than half of all cases, and the perfectly acceptable cases were the least common. There is an urgent need to improve the endodontics teaching programmes in the College of Dentistry of Taibah University. This research should be repeated in the future to evaluate improvement in the performance of RCT by undergraduate dental students in Taibah University.

Radiographic technical quality of root canal treatment performed by undergraduate dental students at the Academy Dental Teaching Hospital, UMST, Sudan

Aim:

To radiographically evaluate the technical quality of root canal treatment performed by undergraduate dental students and compare the findings with other institution's work.

Materials and Methods:

A retrospective, cross-sectional study was conducted at the Academy Dental Teaching Hospital involving postoperative periapical radiographs of patients who were endodontically treated by batch #14 undergraduate dental students of final year (2013–2014) from UMST, Sudan. The total number of the students was 21, while periapical radiographs fulfilling the required criteria were 173. The radiographs of each case were evaluated in terms of length, density, and taper of the root canal filling. Procedural errors such as presence of a ledge, perforation, and a separated instrument were also recorded. Chi-square test was used to determine statistically significant differences between variables, with the level of significance set at P ≤ 0.05.

Results:

The overall quality of performed root canal treatment was adequate in almost half (55.5%) of the evaluated teeth. The length and taper of the root canal filling were found to be significantly associated with maxillary and mandibular posterior teeth with P = 0.018 and 0.006, respectively. No associations were found between the density and presence of separated instrument in the maxillary and mandibular posterior teeth, P = 0.314 and 0.480, respectively.

Conclusion:

The radiographic quality of root canal treatment performed by undergraduate students of batch #14 UMST was acceptable in 55.5% of the cases. Special emphasis must be placed on the educational methods and training of students for providing root canal treatment on molar teeth.

Effects of Clinical Training and Case Difficulty on the Radiographic Quality of Root Canal Fillings Performed by Dental Students in Saudi Arabia

Introduction:

The aim of this study was to evaluate the effects of training duration and case difficulty on the radiographic quality of root canal fillings performed by dental students in Saudi Arabia.

Methods and Materials:

A longitudinal cohort study was conducted at King Saud University. Root canal treatments performed by 55 dental students from 2012-2014 were included in the study. Each student treated at least five teeth during the first year of clinical endodontic training and another five teeth during the second year. Case difficulty was assessed based on tooth position in the dental arch and preoperative conditions. The radiographic quality of the root canal filling was evaluated by two endodontists blinded to treatment completion date. The evaluation criteria were adequate obturation, presence of mishaps and preparation taper. The data were statistically analysed using univariate and multivariate logistic regression analyses; and the level of significance was set at 0.05.

Results:

Inadequate obturation and mishaps were significantly less prevalent in teeth treated after 2 years of clinical training. The odds ratios for inadequate obturation and mishaps increased significantly as tooth position moved posteriorly. Inadequate obturation and more mishaps were significantly more prevalent in teeth with preoperative conditions. Preparation taper was not significantly affected by training duration or case difficulty.

Conclusion:

The quality of root canal fillings performed by Saudi students was adversely affected by case difficulty. The radiographic quality of root canal fillings improved significantly after 2 years of clinical training. Preparation taper outcome is likely dependent on the preparation technique and instrument taper.

The confidence of undergraduate dental students when performing root canal treatment and their perception of the quality of endodontic education

AIM

This article aims to gain understanding into the perception of undergraduate dental students in terms of their confidence and competence at performing root canal treatment and their perception of the quality of endodontic education.

METHODS

An online questionnaire was distributed to all 3rd, 4th and 5th year dental students at Cardiff University via their academic e-mail addresses. The questionnaire utilised both scaled response and open questions to gain an insight into undergraduate opinion.

RESULTS

Out of a possible 208 students, 98 responses were obtained (response rate = 47%). Perception of competence and confidence were significantly greater amongst the more senior year groups (P < 0.01). However, 49% (n = 38) of participants did not feel competent performing root canal treatment on anterior, single-rooted teeth, whilst 74% (n = 70) did not feel competent performing root canal treatment on posterior, multirooted teeth. Free comments from participants indicated that this was due to a lack of clinical experience. Approximately, 80% of participants ranked education in endodontics at Cardiff University as ≤5 on a Likert scale (1 = inadequate to 10 = good), indicating that improvement was required. Improvements that were suggested by the students included the provision of further information within lectures, a broader range of lecturers, an increased number of shorter, more organised practical sessions, additional training equipment, greater supervision and online reference guides to root canal treatment.

CONCLUSION

Enhancing undergraduate education in endodontics is necessary to increase students' perception of their confidence and competence when performing root canal treatment.

Technical quality of root canal therapies performed by novice dental students in preclinical practice

Background:

For improving the quality of endodontic performance of practitioners in clinical practice, their basic, preclinical performance and knowledge must be taken into consideration. This study aimed to radiographically evaluate the technical quality of preclinical molar root canal treatments (RCTs) performed by undergraduate dental students at a dental school in Iran. Further, the effect of using Gates-Glidden (GG) drills on the final quality of RCTs was evaluated.

Materials and Methods:

In this retrospective cross-sectional study, 315 roots of 105 endodontically treated teeth in preclinical practice were evaluated radiographically. The analyzed quality parameters included length, taper and density of fillings, which were scored as S2 (adequate standard), the S1 (slight deviation), or S0 (considerable deviation). For all the parameters, acceptable, moderate and poor fillings received total scores of 6, 3-5 and 0-2, respectively. There were two groups of students: One group had used only K-files, and the other had used K-files along with GG drills. The quality of RCTs between these groups was evaluated using the aforementioned scoring protocol. The results were analyzed using Chi-square, Mann–Whitney and Fisher's exact tests (α = 0.05).

Results:

Under-fillings (P = 0.001) and under-shapings (P = 0.007) occurred mostly in mandibular root fillings. A lower density was found in maxillary fillings (P < 0.001). No relationship was observed between the technique used (irrespective of GG drills usage) and length (P = 0.499) and taper of fillings (P = 0.238). The roots instrumented with GG drills had a higher filling density (P = 0.004). The quality mean score of RCTs was improved when GG drills were used (P = 0.008).

Conclusion:

The technical quality of preclinical molar RCTs performed by undergraduate dental students was considered acceptable in 35.6% of the cases. When GG drills were used along with K-files, the technical quality of RCTs was enhanced.

Technical quality of root canal treatment of posterior teeth after rotary or hand preparation by fifth year undergraduate students, The University of Jordan

The aim of this study was to investigate the technical quality of root canal treatment provided by the undergraduate students as their first experience in molar endodontics using nickel-titanium (NiTi) files in a crown-down approach compared with stainless steel standard technique. This study was carried out by the fifth year undergraduate students attending peer review sessions as a part of their training programme, using two different questionnaires to assess the overall technical quality and potential problems regarding endodontic complications after root canal preparation with these two techniques. The overall results indicated a statistically significant difference in the performance of the two instrument techniques in difficult cases showing better performance of the NiTi system and mean rotary preparation time (P < 0.001). Under the conditions of this study, novice dental students, using NiTi ProTaper rotary files, were able to prepare root canals faster with more preparation accuracy compared with canals of same teeth prepared with hand instruments.

Radiographic technical quality of root canal treatment performed ex vivo by dental students at Valencia University Medical and Dental School, Spain

Objectives: To evaluate radiographically the quality of root canal fillings and compare manual and rotary preparation performed on extracted teeth by undergraduate dental students. Study Design: A total of 561 premolars and molars extracted teeth were prepared using nickel-titanium rotary files or manual instrumentation and filled with gutta-percha using a cold lateral condensation technique, by 4th grade undergraduate students. Periapical radiographs were used to assess the technical quality of the root canal filling, evaluating three variables: length, density and taper. These data were recorded, scored and used to study the “technical success rate” and the “overall score”. The length of each root canal filling was classified as acceptable, short and overfilled, based on their relationship with the radiographic apex. Density and taper of filling were evaluated based on the presence of voids and the uniform tapering of the filling, respectively. Statistical analysis was used to evaluate the quality of root canal treatment, considering p < 0.05 as a statistical significant level. Results: The percentage of technical success was 44% and the overall score was 7.8 out of 10. Technical success and overall score were greater with rotary instruments (52% against 28% with a manual one, p < 0.001; 8.3 against 6.7 respectively, p < 0.001). Conclusions: It appears that inexperienced operators perform better root canal treatment (RCT) with the use of rotary instrumentation.

Key words:Dental education, endodontics, rotary instrumentation, radiographs, root canal treatment, undergraduate students.

Evaluation of an improved endodontic teaching model: do preclinical exercises have an influence on the technical quality of root canal treatments?

AIM

To investigate whether the preclinical application of an electronic root canal length measurement device (ERCLMD) leads to more accurate working length (WL) determinations in a preclinical endodontic course and if this exercise effects the technical quality of root canal procedures when treatments are performed on patients for the first time.

METHODOLOGY

Root canal treatments performed by two consecutive groups of third year students (group 1: n = 39, group 2: n = 44) were compared in the preclinical course and when root canal treatments were performed on patients in the following term. Two different teaching models were applied in the preclinical endodontic course. WL in group 1 was determined with radiographs only. The teaching model applied in group 2 allowed the application of an ERCLMD. When treatments were performed on patients, both groups used the same technique to determine WL. It was first determined using an ERCLMD and verified radiographically. Master cone and root filling lengths were evaluated using radiographs, and comparisons between both groups were made using Fischer's exact test.

RESULTS

Root fillings performed by students of group 2 were more often classified as acceptable. This observation was made in the preclinical endodontic course and when treatments were performed on patients.

CONCLUSIONS

The application of an ERCLMD in combination with radiographs is more accurate to determine WL than radiographs alone. Students practiced the use of ERCLMDs with the new model and benefited from this experience when performing their first root canal treatments on patients.

Radiographic assessment of the technical quality and periapical health of root-filled teeth performed by general practitioners in a Turkish subpopulation

Aim. The aim of this study was to evaluate by means of radiographs the technical quality of root fillings performed by dental practitioners. Methods and Material. Standardized periapical radiographs were made on 484 patients who received endodontic treatment in private practice. A total of 831 endodontically treated teeth with 1448 roots were evaluated for technical quality of the root canal filling and the periapical status of the teeth. Also, the apical status of each root-filled tooth was assessed according to the length, density, and taper of root fillings, and the presence of apical transportation, broken root instruments, and overfilled sealer or gutta-percha material was recorded for each root canal. Results. Of the endodontically treated teeth 26.6% had healthy periapical tissues, while technically good endodontic treatment constituted 12.8%. Based on the treatment success, there was no significant difference between the tooth groups. Statistical analysis of the data did not demonstrate statistically significant differences between the various parameters that were evaluated (P < 0.05). Conclusions. Technical quality of root fillings in a population who received treatment in private practice was poor and was consistent with a low prevalence of apical health. The probable reasons for this failure are multifactorial and may be improved if the operators improve their skills with continuing postgraduate education programs.

Dental students' perceptions about the endodontic treatments performed using NiTi rotary instruments and hand stainless steel files

This study evaluated the perceptions of Brazilian undergraduate dental students about the endodontic treatments performed using NiTi rotary instruments and hand stainless steel. Data were collected using a questionnaire administered to undergraduate dental students enrolled in endodontic disciplines. The students were divided into 3 groups: G1, students who had treated straight canals with SS hand instruments; G2, students who had treated curved canals with SS hand instruments; and G3, students who had treated both straight and curved canals with NiTi rotary instruments. The number of endodontic treatments performed, types of treated teeth, students' learning, time spent, encountered difficulties, quality of endodontic treatment and characteristics of the employed technique were analyzed. There was a 91.3% rate of return for the questionnaires. Mandibular molars were the most frequently treated teeth, followed by maxillary incisors. The Kruskal-Wallis test showed no differences in learning (p=0.528) or in the characteristics of the technique employed (p=0.560) among the three groups. G3 students performed a greater number of endodontic treatments (p<0.001) in a smaller time (p<0.001) than did G1 and G2 students. Difficulties were reported primarily by students in G2 and G3 compared with G1 (p=0.048). The quality of endodontic treatments differed only between G1 and G2 (p=0.045). The use of NiTi rotary instruments should be included in undergraduate dental curriculum, contributing to the increase of patients assisted and consequently to improve the clinical experience of the students.

Effect of waiting interval on chemical activation mode of dual-cure one-step self-etching adhesives on bonding to root canal dentin

OBJECTIVES

The purpose of this study was to evaluate the effect of waiting interval on the chemical activation of dual-cure one-step self-etching adhesives before placing resin core materials on the regional bond strength to root canal dentin.

MATERIALS AND METHODS

Forty-eight post spaces prepared in human lower premolars were applied with four dual-cure one-step self-etching adhesives Estelite Core Quick: ECB/ECQ, Clearfil DC Core Automix: CDB/CDC, Unifil Core EM: UNB/UNC, BeautiCore: BTB/BTC as the manufacturers' instructions. These adhesives were cured with light activation for 10 s, or chemical activation with 0, 10, and 30 s waiting intervals prior to placing resin core material. Resin core materials were then placed into the post space and light-cured for 60 s. After 24h water storage, each specimen was serially sliced into 8, 0.6 mm × 0.6 mm thick beams for the μTBS test. The regional μTBS data were analyzed using three-way ANOVA and Dunnett's T3 test (p < 0.05).

RESULTS

For the chemical activation with 10 and 30 s waiting intervals, ECB and CDB exhibited significantly improved μTBS, whereas for UNB and BTB, the μTBS were not significantly different but increased with waiting interval. On the other hand, light-activation of all the adhesives produced significantly higher μTBS to root canal dentin than chemical activation (p < 0.05), except for the UNB group.

CONCLUSIONS

For the chemical activation of dual-cure one-step self-etching adhesives, a waiting interval prior to placing resin core material improved μTBS to root canal dentin. Polymerising the adhesives before polymerisation reaction of resin core material would be effective for bonding to root canal dentin.

CLINICAL RELEVANCE

For chemical activation mode as well as light activation mode, pre-curing of adhesive layer before proceeding polymerisation of resin filling material would produce higher bonding performance to dentin in the cavity.

Radiographic quality of root fillings performed by undergraduate students

AIM

To evaluate the radiographic technical quality of root fillings and the incidence of iatrogenic errors in treatment provided by undergraduate students.

METHODOLOGY

Endodontic records and periapical radiographs of 759 root filled teeth were selected following exclusion of 25 (3.3%). A final total of 734 cases were used to assess the technical quality of root fillings in 1109 root canals performed by 4(th) and 5(th) undergraduate students. Two variables were examined: the length and the density of the fillings, categorized as acceptable and non-acceptable. The presence of ledges, root perforation, foramen perforation and fractured instruments were also investigated. Chi-square tests were used for statistical analysis.

RESULTS

Acceptable root fillings were found in 55% of canals. More ;acceptable' root fillings occurred in maxillary compared to mandibular teeth (58 and 51% respectively) (P < 0.05) and in anterior compared with premolar (71 and 61%) and molar root canals (39% respectively) (P < 0.05). Insignificantly more (5.4%) acceptable root fillings were provided by 5(th) year students. Most of the underfillings and iatrogenic errors were detected in molars for both academic years (53 and 65% respectively). Ledges were noted in 55% of cases treated by both academic years and significantly more foramen perforations were detected in the 5(th) compared with the 4(th) year students (P < 0.05).

CONCLUSIONS

There is a need to improve the technical quality of root fillings performed by the undergraduate students, especially in molar teeth.

Radiographic evaluation of the technical quality of root canal fillings performed by dental students

The objective of this study was to evaluate radiographically the technical quality of root canal fillings performed by dental students at the School of Dentistry, University of the West Indies. The school's database between 2000 and 2004 was investigated for patients with completed root canal treatment. The final sample consisted of 198 patients with 288 root-filled teeth and 460 canals. The length, presence of voids, taper, curvature of canal and fractured instruments were recorded and scored. Chi-squared analysis was used to determine statistically significant differences between the technical quality of root fillings and tooth type. Sixty-three per cent, 27.6% and 72.2% of root-filled canals had adequate length, density and taper respectively. The overall acceptability of root fillings having adequate length and taper, absence of voids and no fractured instruments was found in 10.9% of canals. Changes in teaching methods may be required to improve the technical quality of root canal treatment done by dental students.