Comparison of the accuracy of apex locator, digital radiography, and cone-beam computed tomography in root canal working length determination in teeth with external root resorption: An in vitro study.

Background: The aim of this study was to compare the accuracy of apex locator, digital periapical radiography, and cone-beam computed tomography (CBCT) for determining the root canal working length (WL) in teeth with external root resorption (ERR). Materials and Methods: In this in vitro study, the sample consisted of 54 extracted permanent single-rooted human teeth. ERRs were performed at the 3 mm apical root using 65% of nitric acid for 24 h. After determining the actual WL by K-file #10 (gold standard) with the visualization method, the teeth were mounted in alginate and the WL of each tooth was determined using the electronic apex locator (EAL) equipped with a K-file #15. The teeth were mounted with wax in the teeth sockets of a dry human mandible, and the images were obtained by digital phosphor plate receptors and CBCT scans. The mean registered WL of each method was statistically compared with the gold standard WL using one-way ANOVA with P < 0.001. Results: The mean ± standard deviation (SD) of actual WL was 16.00 ± 2.24. The mean ± SD of WLs determined by CBCT, EAL, and digital radiography were 15.38 ± 2.19, 15.52 ± 2.32, and 16.83 ± 2.20, respectively. This study showed that the mean measured WL with ERR in all methods was significantly different from the actual WL (P < 0.001). Conclusion: This study showed that there was a significant difference between the actual mean WL and the EAL, digital periapical radiography, and CBCT mean WL. Thus, the combination of EAL and CBCT could be a reliable method for determining WL in the presence of ERR.

Effect of premedication on the success of inferior alveolar nerve block in patients diagnosed with irreversible pulpitis: An umbrella review.

Successful management of pain during endodontic treatment is essential for both patients and dentists. Achieving adequate pulp anesthesia in mandibular molars is a significant concern for patients with irreversible pulpitis during endodontic treatment. The increased sensitization of nociceptors due to inflammation decreases the success of inferior alveolar nerve block (IANB). The main focus is on reducing inflammation before delivery of local anesthesia to increase the success of anesthetic drugs. This umbrella review aimed to revise, qualify and summarize the existing body of evidence on the effect of premedication on IANB in patients with irreversible pulpitis. A literature search was conducted using electronic databases (PubMed, Scopus, the Web of Science, and the Cochrane Library) with no date restriction until September 2021 to identify the relevant studies. All the cross-references of the selected studies and grey literature were also screened. Four systematic reviews assessing the effect of premedication on the success of IANB were selected. A conclusion was drawn that premedication with >400 mg of ibuprofen can positively affect the success of IANB.

The effect of micro-osteoperforation on root resorption, pulp vitality, and biological changes of teeth subjected to orthodontic tooth movement: A systematic review study.

Background: These days minimally invasive micro-osteoperforation (MOPs) has accelerated orthodontic tooth movement (OTM). However, there are some conflicting reports about their various impacts; hence, the present systematic review study aimed to evaluate the effect of MOP on root resorption, pulp vitality, and the biological changes of teeth subjected to OTM. Materials and Methods: Search in electronic databases of English literature including PubMed, Scopus, Web of sciences, Cochrane, and Google scholar as well as a manual search was performed from 2013 to 2022. Most of the studies included in this article were randomized controlled trials. Results: From the total number of 321 found articles, 31 duplicated and 268 irrelevant articles were excluded regarding the defined inclusion and exclusion criteria. Consequently, 22 articles were subjected to the quality assessment process, and finally, 18 articles were selected for the review phase. Root resorption during tooth movement using the MOP approach was reported only in one study. Besides, except for two animal studies, all of the relevant included articles showed that MOPs significantly increased the expression of some inflammatory biomarkers known to recruit osteoclast precursors and increase the number of osteoclast cells. On the other hand, two animal studies showed no differences in osteoclast counts by using MOPs in comparison to their control groups, which was consequently the result of biologic variability between animal and human and also probably the small sample sizes of these two studies. Conclusion: In this systematic review, according to the adverse effects of MOP on root resorption, one study showed higher levels of root resorption among patients undergoing MOP. However, this outcome was due to the different methods used to evaluate the effect of MOPs on root resorption. Moreover, a high certainty of evidence supports that MOP causes biological changes and an elevation in cytokines, chemokines, and other biomarkers that stimulates osteoclasts differentiation which in turn accelerate OTM. There was no change in pulp vitality status based on available evidence.

Effect of Citric Acid Versus EDTA on Radiographic Root Development in Regenerative Endodontic Treatment: An Animal Study.

INTRODUCTION: Regenerative endodontic treatment was introduced with the aim of reinforcing the root and enabling further root development. In the process of dentin mineralization, bioactive molecules are entrapped in the dentin matrix, which can be released later by rinsing the dentin with chelating agents. This study aimed to compare the effects of citric acid and EDTA on radiographic root development in regenerative endodontic treatment in an animal model. METHODS: Premolars of 3 beagle dogs were used in this study. The teeth at 1 side of the jaw were irrigated with EDTA according to the regeneration protocol of the American Association of Endodontists. The teeth in the other quadrant were irrigated with citric acid in the second treatment session. Follow-up radiographs were obtained at 6 months, and the primary and final data were analyzed in SPSS Version 23 (IBM Corp, Armonk, NY) using the analysis of covariance. RESULTS: There was no significant difference between the 2 irrigating solutions regarding the increase in root length (P = .668); however, EDTA showed significantly superior efficacy in increasing the root dentin thickness compared with citric acid (P = .022). CONCLUSIONS: Within the limitations of this study, the use of citric acid versus EDTA was not superior on radiographic root development in regenerative endodontic treatment.

Anatomy assessment of permanent mandibular premolar teeth in a selected Iranian population using cone-beam computed tomography.

BACKGROUND: Appropriate cleaning and shaping and three-dimensional obturation of the root canal system lead to a successful endodontic treatment. To achieve this, complete knowledge of the internal anatomy of root canals is necessary. Therefore, this study evaluated the number and shape of mandibular premolar roots and canals and classified their Vertucci classification using cone-beam computed tomography (CBCT) images of an Iranian sample population. MATERIALS AND METHODS: This in vivo study was performed on CBCT images of patients aged 20-70 years who had attended a dental radiology center in Isfahan. CBCT images were examined in coronal, sagittal, and especially axial dimensions. Descriptive statistics were calculated. Groups were compared using the Chi-square of the Statistical Package for the Social Sciences. The level of significance was predetermined as 0.05. RESULTS: In both first and second premolars, the most common classes were Type I followed by Type V. The Chi-square did not show significant differences between males and females in terms of Vertucci classes in the first (P = 0.305) or second premolar (P = 0.315). CONCLUSION: Since a thorough knowledge of root canal anatomy is necessary for successful root canal treatment and almost one out of ten mandibular premolars has additional canal in their root canal system, accurate evaluating of preoperative radiographs, taking CBCT images if necessary, and probing the root canal system with fine and precurved files should be done to negotiate the entire canal system.

Effect of Phentolamine as Reversal of Soft-Tissue Anesthesia on Post-Endodontic Pain in Patients with Symptomatic Irreversible Pulpitis: A Randomized Clinical Trial.

Introduction: Phentolamine mesylate (OraVerse) is mostly used to reverse soft tissue anesthesia after dental procedures. The aim of the present study was to evaluate the effect of the injection of OraVerse on postoperative pain after root canal treatment in patients with symptomatic irreversible pulpitis. Methods and Materials: In this randomized single-blind clinical trial study, 100 patients (50 per group) with symptomatic irreversible pulpitis in the first or second mandibular molars, randomly received either OraVerse or sham treatment after a single-visit root canal therapy. Each patient recorded their pain score, using a Heft Parker visual analogue scale, before and after 6, 12, 24, 36, 48, and 72 h of the treatment. They also monitored their soft-tissue anesthesia every 15 min for 5 h. Data were analyzed by t-test and repeated measured ANOVA statistical tests. The level of significance was set at 0.05. Results: Patients who received phentolamine had significantly higher pain scores at 6- and 12-h postoperative intervals compared with those receiving sham treatment (P=0.01 and P=0.00 respectively). Consumption of analgesics in OraVerse group was significantly higher than that of the sham group (P=0.48). Conclusion: Although phentolamine accelerated the reversal of normal soft tissue sensation after the dental visit, it increased postoperative pain in patients suffering from symptomatic irreversible pulpitis, which may limit phentolamine administration in this group.

Evaluation of Relationship between Exposure Parameters and Maxillofacial Bone Quality with Salivary Glands Absorbed Dose in Cone Beam Computed Tomography Imaging.

AIM: The purpose of this study was to evaluate the protective effect of jaw bone on the dose of salivary glands and its relationship with radiation conditions. MATERIALS AND METHODS: In this cross-sectional study, seven dried human skulls were used. In each mandible, six dosimeters were placed in six salivary gland regions numbered in visible light absorbent envelopes. Cone beam computed tomography (CBCT) images were taken from each mandible with a constant kV of 90 and mA varied from 6, 8, and 10. The absorbed dose was calculated using SOLAR 2A. The bone quality of each of the six areas was obtained using densitometry tool in On Demand software. Finally, the results were analyzed using Statistical Package for the Social Sciences (SPSS) software version 23 with covariance and Tukey tests (α = 0.05). RESULTS: The results of covariance analysis and Tukey test indicated that the sublingual salivary gland had the highest absorption dose. Meanwhile, the results of the analysis showed that the absorption rate of the glands increased by increasing the radiation conditions from 6 to 8 and increasing from 8 to 10 mA (p < 0.001). The results of Pearson analysis showed an inverse relationship between absorbed dose and bone quality (r = -0.327) (p < 0.001). CONCLUSION: The results of this study showed that the absorption rate of salivary glands will increase with increasing radiation conditions, while increasing the quality of mandibular bone, the absorption dose will decrease. CLINICAL SIGNIFICANCE: The clinical significance is to reduce patient's absorbed dose in order to decrease the risk of mutation and cancer formation.

Comparison of Accuracy of determining the Distance between Alveolar Crest and Cementoenamel Junction in Digital Radiography with Scanora and DentalEye Software Programs.

AIM: To compare the accuracy of determining the distance between alveolar crest and cementoenamel junction (CEJ) in digital radiography with two image processing software programs. MATERIALS AND METHODS: In this in vitro study, 63 sites in a dried human mandible underwent digital periapical radiography. The distance from the alveolar crest to the CEJ was calculated using DentalEye and Scanora software programs and compared with the standard mode (measured on the skull). Statistical analysis was performed with analysis of variance (ANOVA) and paired t-test using Statistical Package for the Social Sciences (SPSS) 23 at α = 0.05. RESULTS: There were significant differences in the distances between CEJ and the alveolar crest at the mesial surfaces as measured by the three techniques in standard mode, using DentalEye and Scanora (p-value ≤ 0.03) softwares; however, there were no significant differences between the results on distal surfaces (p-value = 0.248). CONCLUSION: Under the limitations of the present study, the measurements made to determine the distance from the CEJ to the alveolar crest with DentalEye and Scanora, relative to each other, and relative to the standard mode, were accurate only on distal surfaces of teeth. CLINICAL SIGNIFICANCE: Digital dental software programs are useful assets that can enhance the diagnosing ability and reduce the need of taking extra images.