mohammad mahdi yaghooti khorasani

To be successful in root canal therapy, the dentists must be aware of the possible variation in the root canal and should know not only the natural anatomy of the pulp, but also a variety of possible morphologies. Frst of all, the dentists should be familiar with the possible anatomy of the root canal and then with the extraction of organic tissue from pulp chamber and root canal, increasing the chances of treatment success. Therefore, in this study, we decided to investigate the internal anatomy of root canals in the maxillary permanent molar teeth in Khoy city.

In this in vitro study, 100 extracted human molars in Khoy city in West Azerbaijan province were collected. In all teeth, the access cavities were prepared, then they were decalcified and colored with India ink and evaluated by clearing technique. Data were collected based on Vertucci's classification which entered into SPSS23 software. The descriptive statistics in the form of numbers and percentages in tables and graphs were used to analyze the data.

The most common type observed in the mesiobuccal root of the first molars was type IV by 44%, in distobuccal root was type I by 92%, and in palatal root was type I by 94%. Also, in the mesiobuccal root of the second molars, the most common type was type I by 70%, in distobuccal root was type I by 94%, and in palatal root was type I by 96%.

The mesiobuccal root of the first molar had the most variation in the internal anatomy. Also, the most common type of Vertucci in the mesiobuccal root of first molar was type IV and in the other roots of the first and second molar teeth was type I.

The students’ self-confidence level is a key factor affecting the success of endodontics learning. This study aimed to determine the confidence level of dental students who performing root canal treatment at Rafsanjan University of Medical Sciences in 2021.

In this cross-sectional study a questionnaire including demographic information, endodontic experience, attitude toward confidence in performing different stages of root canal treatment, and suggestions for improving the quality of endodontic education was distributed to dentistry students of 54 5th and 6th-year in the last month of the academic semester. Data were analyzed using t-test, Pearson, and ANOVA tests (α = 0.05).

According to the results, from 49 dental students, 24.5% reported the first cases of root canal treatment to be severe. The lowest confidence was reported for finding all root canals in teeth with multiple root canals, preparing access cavity and understanding and managing root canal treatment risks. According to the results of chi-square analysis test, the total confidence score between 5th and 6th year students was not significantly different (p value = 0.648). Also, the relationship between general self-confidence and students' self-confidence level was not seen (p value = 0.372). There was no significant relationship between the Confidence level and age, academic year, the difficulty level of the first endodontic treatment, and number of endodontic treatments (p value > 0.05).

Students had lower self-confidence finding all the canals in multi-canal teeth, how to properly manage the treatment risks, and preparing the access cavity. Endodontics training should also be improved by increasing clinical sessions and using recent advances in endodontics.

Due to the association of post- and pre-endodontic pain, using non-steroidal anti-inflammatory drugs (NSAIDs) before root canal therapy could interfere with the subsequent inflammatory process and reduce post-endodontic pain. The present study aimed to compare the effectiveness of prophylactic gelophen, Advil (two types of NSAIDs), and placebo in controlling the pain after root canal therapy.
This triple-blind clinical trial was conducted on 48 patients with a vital, single root canal anterior tooth. The teeth samples were divided into three groups. The patients in each group received one capsule as pre-treatment prophylaxis, which contained gelophen, Advil or placebo depending on the codes. Standard root canal therapy was performed by a general dental practitioner. Level of pain in each patient was recorded before the treatment and at 6, 12, 24, 48, and 72 hours after the treatment using the visual analog scale (VAS). After collecting the data, mean pain score was compared in the study groups. Data analysis was performed using Chi- square and repeated measures ANOVA.
In the patients administered with Advil and gelophen, pain reduction was more significant than the placebo group at all the intervals after the treatment compared to the pre-treatment phase. However, no statistically significant difference was observed between the intervals in this regard (P>0.05).
According to the results, the prophylactic use of Advil and gelophen is effective in the reduction of post-endodontic pain, while there is no significant difference in their efficacy.

Background. Digital radiography has widespread use in endodontics. Determining a correct working length is vital for a proper endodontic therapy. The aim of this study was to compare the accuracy of conventional and digital radiographic techniques for root canal working length determination.
Methods. After determining the real working lengths of 50 permanent maxillary central incisors (gold standard), the conventional (E- and F-speed films) and digital (CCD, PSP) images were obtained using the parallel technique. The mean registered working length of each modality was compared with the other and with the gold standard using one-way ANOVA at PResults. No significant difference was found between the recorded working length values using the conventional and digital radiographic techniques (P=0.828).
Conclusion. Within the limitations of this study, it was concluded that there was no difference between the measurement accuracy of CCD, PSP and conventional imaging techniques in root canal working length determination.

Bacteria and their products have an important role in root treatment failure and their continued presence in seemingly well-filled canals, cause disturbances in healing process after the treatment. Thus the use of proper disinfectants for mechanical cleaning of canals has a great importance. Nowadays, scientists are seeking better alternatives with greater efficiency and less toxic effect for common chemical disinfectants. Therefore, the aim of this study was to evaluate the antimicrobial effects of Matrica and Chlorhexidine compared to Sodium hypochlorite on Enterococcus faecalis and Candida albicans in the laboratory conditions.
In this in vitro study, Candida albicans and Enterococcus faecalis microorganisms were cultured with Kirby Bauer method on Mueller Hinton agar medium. Then paper disks impregnated with Matrica (pure and 50%), chlorhexidine (0.2% and 0.1%) and sodium hypochlorite 1% were placed on the medium. Forty-eight hours later, the zone of growth inhibition was measured in terms of millimeters. Data were analyzed by SPSS-18 software using ANOVA and TUKEY statistical tests.
According to the findings of this study, the highest mean diameter of inhibition zone of bacteria Enterococcus faecalis and Candida albicans, was for sodium hypochlorite 1% followed by chlorhexidine 0.2%, chlorhexidine 0.1%, pure Matrica and Matrica 50%, respectively (P Considering the results of this study, it seems that the antimicrobial effect of herbal composition of Matrica is not as efficient as sodium hypochlorite and chlorhexidine.

Root canal therapy of teeth can stop the endodontic pain, but the cousequent post-endodontic pain and discomfort are undesirable effects. There are many studies on various drugs for alleviation of post-endodontic pain. The purpose of this study was to compare the Efficacy of prophylactic use of Teltonal in comparison with Ibuprofen on post- endodontic pain. In this triple-blind clinical trial study, 57 patients with anterior vital single rooted teeth and severe decay were selected. Patients were divided into three groups of A, B and C. One capsule was given to each patient as prophylaxis before the treatment, which according to its code contained Ibuprofen, Teltonal or Placebo. Intensity of pain was recorded by the patients before treatment and 6,12,24,48 and 72 hours after the treatment using a VAS scale. The collected data were processed in SPSS-21, and to compare pain during the evaluation periods in all three groups studied, two-way repeated measure ANOVA was used. In each of the three study groups during the evaluation period, the average pain was significantly reduced (P<0.001). However, the difference between the gtoupd was not statistically significant (P=0.347). Since no statistically significant difference was observed between the groups, prophylactic use of these drugs for reduction of post-endodontic pain is not suggested.

Good apical seal plays a critical role in the success of endodontic treatment and the smear layer reduces the efficacy of the apical seal. The aim of this study was to evaluate the effect of Nd:YAG laser irradiation on the apical seal of root canal-treated teeth using the fluid filtration technique. In this in vitro study, 44 human maxillary central incisors were selected. After preparation, the specimens were randomly assigned to 4 groups: group A, the control group (n=20); group B, the laser-treated group (n=20); group C, the positive control group (n=2); and group D, the negative control group (n=2). All the groups were prepared using the crown-down technique. Group B was irradiated with Nd:YAG laser before obturation. Groups A, B and D were obturated with gutta-percha and sealer and group C was obturated with gutta-percha and without sealer. The coronal end of the specimens were sealed with amalgam and then stored in an incubator for one week. Then, the outer surface of groups A, B and C, except for 2 mm in the apical area, and group D were entirely covered with two layers of nail polish and one layer of sticky wax. Apical microleakage was then evaluated using fluid filtration technique. Data were analyzed with SPSS 18, using Kolmogorov-Smirnov and independent t-test (α=0.05). The means of apical leakage in the laser and control groups were 4.35±2.88 and 5.34±3.13 µL/min/cm H2O, respectively, with no significant differences (p value = 0.305). Under the limitations of this study, use of Nd:YAG laser in root canal therapy had no significant effect on apical microleakage.

Endodontic treatment causes local trauma and subsequent inflammation, making pain and discomfort common side effects of endodontic treatment. Since there is an important relationship between post- endodontic pain and preendodontic pain, use of non-steroidal anti-inflammatory drugs (NSAIDs) before root canal therapy can suppress the inflammatory process before it starts, and reduce the pain after root canal therapy. The aim of this study was to compare the efficacy of prophylactic Ibuprofen Sulindac (both are NSAIDs) and placebo in controlling pain after root canal therapy. In this triple-blind clinical trial study, 48 patients with vital, single rooted anterior teeth were selected. These teeth were divided into three groups. One capsule was given to every group as prophylaxis before the treatment, which according to its code, contained Ibuprofen, Sulindac, or placebo. The treatment was then performed by one person (a general practitioner) according to standard methods. The pain of each patient was recorded before treatment and at 6, 12, 24, 48, and 72 hours after the treatment using a VAS scale. The results were collected and comparison of the means of pain between the three groups was conducted statistically. A reduction in pain was seen in Sulindac and Ibuprofen group at 6,12,24,48, and 72 hours after treatment compared to before treatment and placebo group, but the difference was not statistically significant (P>0.05). Since no statistically significant difference was observed between the groups, prophylactic use of these drugs for reduction of post-endodontic pain is not suggested.

Applying the suitable mouthwash can kill bacteria or reduce the bacterial growth; in the same context, diluting mouthwashes can decrease their probable side effects. In this study, the maximum inhibitory concentrations of two common mouthwashes were evaluated. In this in vitro study, agar dilution and disk diffusion methods were used. Sixty-nine bacterial plates were cultured to evaluate the effects of thymol and chlorhexidine mouthwashes on Streptococcus mutans and Streptococcus sanguis. The results of agar dilution method were recorded as "growth' and "no growth", and the results of disk diffusion were recorded as means of growth inhibitory halos. Data was analyzed by Kruskal-Wallis test using SPSS software. (α = 0.05). Growth inhibitory halos for different concentrations of the two mouthwashes decreased with an increase in dilution rate. In agar dilution method, dilutions less than 80% of the initial concentration for thymol-based mouthwash and less than 70% for chlorhexidine could not inhibit bacterial growth. Growth inhibition halos with 100% thymol-based mouthwash (Orion®) were 10.15 ± 0.1 mm for Steptococcus mutans and 9.2 7 ± 0.16 mm for Streptococcus sanguis. Mean rank of the two mouthwashes was statistically significant for the two bacterial strains under study (p value < 0.001). Both mouthwashes were effective on the bacteria under study; however, this efficacy was higher for Streptococcus sanguis. Chlorhexidine mouthwash was more potent to inhibit bacterial growth than thymol-based mouthwash if diluted.

It is not possible to avoid the occurrence of emergency accidents in private dental offices. In order to manage the emergency accidents, scientific and practical knowledge is necessary. The present study aimed to assess the presence of both medicine and ancillary equipments in dentists’ emergency kit of private dental offices in four southeast cities in Iran. In this descriptive study‚ all dentists working in their private dental offices were invited to help with this survey in four southeast cities in Iran (2007-2008). Data collection method included interview with the dentists‚ observing emergency kit and filling in the checklist by trained experts. Data were analyzed using parametric (t-test) and non-parametric (chi-square & Fisher’s Exact) tests. Among the 126 dentists, 117 dentists accepted to help with the survey (Response rate=92.9%). Mean age of respondents was 36±7.6 years. Mean duration of respondents working in their private offices was 6.6±6.9 years. 53% of respondents had participated in emergency medicine courses and only 39.3% had the emergency medical kit in their private offices. Unfortunately‚ all of the kits were incomplete. Mean age of dentists shows that they would work in their private dental offices for a long time. On the other hand, our results showed that a majority of private dental offices in our study did not have emergency kits or existed emergency kits were incomplete. These results confirm the need for planning and managing emergency medicine courses both for dentists and students in dental schools.