The fate of overfilling in root canal treatments with long-term follow-up: a case series

Cytotoxicity and Bone Biocompatibility of the C-Root SP Experimental Root Canal Sealer

This study evaluated the cytotoxicity and biocompatibility of a new strontium silicate-based root canal sealer (C-Root SP), in comparison with those of iRoot SP and AH plus. The sealer extract was diluted to the concentrations of 100%, 75%, 50%, and 25%. L929 cells were cultured for 24 h, and the absorbance value was determined. Two-way analysis of variance (two-way ANOVA) and sealers were implanted in the tibia of Sprague-Dawley (SD) rats, At 2, 6, and 12 weeks, rats were euthanised. The tissue reaction was evaluated by HE staining. The least significant difference (LSD) t-test and Kruskal-Wallis test were used. The cytotoxicity of C-Root SP and iRoot SP was found to be less than that of AH plus. At 12 weeks, new bone formation was induced around C-Root SP and iRoot SP sealer, but minimal evidence of bone formation was found in AH plus. C-Root SP has low cytotoxicity and superior biocompatibility.

Comparison between AH plus sealer and total fill bioceramic sealer performance in previously untreated and retreatment cases of maxillary incisors with large-sized periapical lesion: a randomized controlled trial

OBJECTIVE

This study aims to assess the efficacy of bioceramic (BC) sealer when applied using the single cone technique (SCT), in comparison to AH Plus sealer applied with the cold lateral condensation technique (LCT), concerning their impact on the healing of large-sized periapical lesions in both untreated and retreatment cases.

MATERIALS AND METHODS

A randomized controlled trial was conducted on 41 patients who had 60 permanent teeth in the maxillary incisors that were accompanied by large-sized periapical lesions. The included teeth were radiographed with cone beam computed tomography (CBCT) images and divided equally into two groups according to the endodontic treatment statute (30 untreated previous cases and 30 retreated cases). Subsequently, teeth received uniform preparation, irrigation, and dressing procedures. Then each group was divided equally according to the used sealer (15 teeth obturated using AH plus sealer with LCT and 15 teeth obturated using BC sealer with SCT). All cases were followed up after 6 and 12 months with CBCT images. Subsequently, the change in periapical lesion diameter (PLD) was observed as an indicator to determine the treatment outcome score. One-way ANOVA and Mann-Whitney U test were used to analyze the PLD changing and scoring the treatment outcome during the follow-up periods. The significance level was set at α = 0.05.

RESULTS

There were no statistically significant differences between untreated and retreatment cases neither using AH plus sealer with LCT nor BC sealer with SCT regarding changes in PLD in the follow-up periods. Moreover, there were no significant differences between groups regarding treatment outcome scores in the follow-up periods. All groups showed a high success rate.

CONCLUSIONS

Successful treatment was achieved for untreated or retreatment maxillary incisor cases accompanied by large-sized periapical lesions using either BC sealer with the SCT or AH Plus sealer with LCT with a similar high success rate up to 12 months follow-up period.

Assessment of dental students' knowledge and performance of master gutta-percha cone selection and fitting during root canal treatment: a pilot study

BACKGROUND

Misconceptions should be detected early in dental students' training to improve their clinical performance. Accordingly, this study aimed to assess undergraduate dental students' knowledge and performance of master gutta-percha (GP) cone selection and fitting during clinical endodontic courses at the College of Dentistry, King Saud University.

METHODS

Ninety-nine undergraduate dental students completed an online survey about their knowledge of master GP cone selection. Forty-five of these students were observed by faculty members in clinical endodontic courses while they fitted master GP cones during root canal treatments. The observers recorded the details of each student's cone-fitting techniques. The data were analysed using t-tests, one-way analysis of variance, and chi-square tests (p < 0.05). Inter- and intra-observer reliability were tested using Fliess' Kappa.

RESULTS SURVEY

All participants had good knowledge of over-extended cone management, while 80.8% knew how to properly manage a short cone. The proper flaring assessment method was selected by 86.9% of the female and 34.2% of the male students, and this difference was statistically significant (p = 0.0001).

OBSERVATION

The students labelled the working length on the master GP cone with an indentation in 64.4% of the cases and by bending the cone 35.6% of the time. Of all students, 84.4% encountered an apical stop, and this rate correlated significantly with the length of the cone on the master apical cone radiograph (p = 0.001). Improper shaping of the canal was the most common cause of ill-fitting cones (83.3%), while 16.7% of the students chose the wrong cone size. The final obturation length was adequate in 80% of the cases; 57.8% of the students were helped by instructors.

CONCLUSIONS

Most students had the basic knowledge required to solve problems related to the selection of master GP cones. However, in the clinical setting, more than half of the students required the assistance of an instructor to adjust their cone's fit. The presence of an apical stop had the most significant effect on the length of the fitted master GP cone on radiography. The most common cause of ill-fitting master cones was improper shaping of the canal.

Comparison of Easydo Activator, ultrasonic and needle irrigation techniques on sealer penetration and smear layer removal in vitro

The effects of Easydo Activator (EA), a new sonic irrigation system, on sealer penetration at the root apex were compared to needle irrigation (NI) and passive ultrasonic irrigation (PUI) in this study. Forty-two single-rooted teeth were prepared and randomly divided into three groups (n = 14): group 1: NI; group 2: PUI; and group 3: EA. A solution of 3% sodium hypochlorite (NaOCl) was used for irrigation. Nine teeth in each group were filled with AH Plus sealer mixed with CY5 fluorescent dye and a single gutta-percha cone. The sealer penetration area, maximum penetration depth and percentage of sealer penetration at 5 mm and 1 mm from the apex were analyzed by confocal laser scanning microscopy (CLSM). The remaining 5 teeth in each group were subjected to test smear layer scores by scanning electron microscopy (SEM). The CLSM evaluation showed that increases in the area, depth and percentage of sealer penetration were detected at 1 and 5 mm from the root apex in the PUI group compared with the NI group, and greater increases were observed in the EA group (P < 0.05). The SEM experiment showed that the lowest scores for the smear layer and debris removal were achieved by the EA group when compared with the PUI and NI groups (P < 0.05). In conclusion, EA was superior to PUI and NI regarding sealer penetration at the root apex during endodontic treatment, and it could provide a new technical idea for clinical root canal therapy.

The effectiveness of single antibiotic paste nitrofurantoin V/S double antibiotic paste in alleviation of post-operative pain of patients suffering from symptomatic irreversible pulpitis-A randomized controlled trial

Objective

The present research evaluated and compared effectiveness between nitrofurantoin and double antibiotic paste in alleviating post-operative pain in patients suffering from symptomatic irreversible pulpitis.

Methods

There were 60 subjects enrolled who were allotted among three groups: Group 1 - Nitrofurantoin, Group 2 - double antibiotic paste, and Group 3 - Control. Succeeding access opening and chemo mechanical preparation, intracanal medicament was placed in the root canals. Using a numerical pain scale, pain scores were measured at the following time intervals: preoperative, 12, 24, 48, and 72 h. One-way ANOVA and post hoc statistical analysis were conducted, with a p-value of ⩽ considered as statistically significant.

Results

Preoperatively, most patients experienced moderate to severe pain. The patients in groups 1 and 2 reported considerable reduction in their pain scores (p ⩽ 0.001) on each time interval. However, patients in group 3 experienced a higher level of pain even at 72 h. No considerable distinction was found among participant's pain scores of groups 1 and 2 (p = 0.193).

Conclusion

For effective pain-relieving, both nitrofurantoin and double antibiotic paste can be successfully used in patients suffering from symptomatic irreversible pulpitis. However, when calcium hydroxide was used, patients experience high levels of pain.

A Review of the research methods and progress of biocompatibility evaluation of root canal sealers

The function of root canal sealer was to achieve an appropriate three-dimensional filling effect by filling the root canal and some irregular lumen, thereby inhibiting the residual bacteria. There were many types of sealers, but research to find the most suitable ones was still ongoing. In recent years, researchers had continuously improved the performance of sealers by developing new sealers or adding active ingredients to the sealers. However, most sealers exhibit varying degrees of cytotoxicity and tissue responses, which affect clinical therapy efficacy. This review describes different technical approaches, and recent research progress in the biocompatibility evaluation of root canal sealers and provides brief insights into this field by summarising the performance studies of different root canal sealers.

The Assessment of Quality of the Root Canal Filling and the Number of Visits Needed for Completing Primary Root Canal Treatment by Operators with Different Experience

The main goal of root canal treatment (RCT) is to eradicate or essentially diminish the microbial population within the root canal system and to prevent reinfection by a proper chemo-mechanical preparation and hermetic final obturation of the root canal space. The aim of this study was to assess the quality of the root canal filling and the number of visits needed for completing RCT by operators with different experience, including dentistry students (4th and 5th year), general dental practitioners (GDPs), and endodontists. Data from medical records of 798 patients were analyzed, obtaining 900 teeth and 1773 obturated canals according to the inclusion and exclusion criteria. A similar number of teeth was assessed in each group in terms of density and length of root canal filling and number of visits. The larger number of visits and the lower quality of treatment was observed for 4th year students than for other groups (p < 0.05); in contrast, the endodontists needed the lowest number of visits to complete RCT and more often overfilled teeth than other operator groups (p < 0.05). Interestingly, no statistical difference in quality of root canal filling was noted between 5th year students, GPDs and endodontists. The treatment of lower teeth demanded statistically more visits than that of upper teeth (p < 0.05). The results of the study emphasize that most of the root canal filling performed by operators was considered adequate, regardless of tooth type, files used and number of visits.