Second mesiobuccal canal segmentation with YOLOv5 architecture using cone beam computed tomography images.

The objective of this study is to use a deep-learning model based on CNN architecture to detect the second mesiobuccal (MB2) canals, which are seen as a variation in maxillary molars root canals. In the current study, 922 axial sections from 153 patients' cone beam computed tomography (CBCT) images were used. The segmentation method was employed to identify the MB2 canals in maxillary molars that had not previously had endodontic treatment. Labeled images were divided into training (80%), validation (10%) and testing (10%) groups. The artificial intelligence (AI) model was trained using the You Only Look Once v5 (YOLOv5x) architecture with 500 epochs and a learning rate of 0.01. Confusion matrix and receiver-operating characteristic (ROC) analysis were used in the statistical evaluation of the results. The sensitivity of the MB2 canal segmentation model was 0.92, the precision was 0.83, and the F1 score value was 0.87. The area under the curve (AUC) in the ROC graph of the model was 0.84. The mAP value at 0.5 inter-over union (IoU) was found as 0.88. The deep-learning algorithm used showed a high success in the detection of the MB2 canal. The success of the endodontic treatment can be increased and clinicians' time can be preserved using the newly created artificial intelligence-based models to identify variations in root canal anatomy before the treatment.

Radiopacity evaluation of calcium silicate cements.

BACKGROUND: The aim of this study was to compare the radiopacity of calcium silicate cements using a digital imaging method. METHODS: Four calcium silicate cements, NeoMTA 2, OrthoMTA, ProRoot MTA, and Biodentine, were used in this study. Disk-shaped samples were prepared from each material and placed on a plexiglass plate. An aluminum step-wedge was placed alongside the samples on a digital sensor and exposed to 70 kVp and 8 mA from 30 cm away for 0.32 s. The greyness values ​​of the tested materials were measured digitally with the system software and compared with those of the step-wedge to determine the equivalent aluminum thickness. RESULTS: The radiopacity values, expressed in equivalent millimetres of aluminum, of the studied materials ProRoot MTA, OrthoMTA, NeoMTA 2, and Biodentine were 4.32 ± 0.17 mm Al, 3.92 ± 0.09 mm Al, 3.83 ± 0.07 mm Al, and 2.29 ± 0.21 mm Al, respectively. Statistically significant differences were found between the mean radiographic density values of the tested materials (p < 0.05). CONCLUSION: ProRoot MTA was the most radiopaque root canal filling material among the tested materials. All materials, except Biodentine, were found to be compliant with the minimum radiopacity requirements of ISO 6876 and ADA 57 standards.

Effect of EDDY and manual dynamic activation techniques on postoperative pain in non-surgical retreatment: a randomized controlled trial.

BACKGROUND: During non-surgical retreatment process, the products such as dentin debris, root canal fillings, irrigation solutions, microorganisms and remaining pulp tissues can extrude to the apical area and can cause the postoperative pain and flare-up. Thus, the aim of this study was to evaluatethe effect of EDDY and manual dynamic activation (MDA) techniques on postoperative pain (PP) associated with retreatment. METHODS: Ninety patients scheduled for retreatment were treated at a single visit. Non-vital mandibular premolar teeth diagnosed with asymptomatic apical periodontitis were included in this study. The patients were divided into two groups (n = 45) on the basis of the need for additional irrigation activation procedures (EDDY and MDA). The patients' post-treatment pain levels were asked to rate the intensity of their pain on a 10-point numerical rating scale (NRS) at the 12th, 24th, 48th, and 72nd h and 7 days.The data were analyzed using the chi-square and Wilcoxon signed-rank test was used for within-group comparisons and Mann Whitney U test was used to compare the groups by time period. RESULTS: The difference in postoperative pain intensity between two groups was statistically significant at 12, 24, 48, and 72 h (p < 0.05). There was no significant difference at 7 days. Moreover, no statistically significant difference was found between the two groups in terms of gender and analgesic medication intake (p > 0.05). Pain intensity after the treatment was lesser in the MDA groupthanin the EDDY group at 12, 24, 48, and 72 h. CONCLUSION: This study could lead us to conclude that the two activation systems can be used during endodontic retreatment with no difference at PP 7 days later. However, a comparison of the groups indicated that the EDDY resulted in significantly more PP at 12, 24, 48, and 72 h. Trial registration ClinicalTrials.gov Identifier: NCT04726670.

Radiological Assessment of Prevalance and Quality of Periapical Status of Endodontic Treatments.

BACKGROUND The aim of this study was to determine the current prevalence and quality of endodontic treatments and investigate the relationship of various factors with posttreatment endodontic disease (PTED) in a Turkish subpopulation. MATERIAL AND METHODS The cone beam computed tomography (CBCT) images of 1069 patients (male, 50.9%; female, 49.1%; mean age, 45.32±13.50 years) were retrospectively analyzed. A total of 20 646 teeth were examined; 1604 had undergone root canal. Periapical status was assessed using a modified CBCT periapical index. The relationship between periapical status and quality of root canal fillings (RCFs) was analyzed statistically using the chi-square test. Multivariate logistic regression was performed to evaluate the effect of individual parameters by adjusting them for other variables. RESULTS A total of 7.8% of all teeth had RCF. The prevalence of poor filling (having at least 1 procedural error) was 54.1%; the prevalence of PTED was 56.8%. The prevalence of PTED was 44.3% in teeth with short RCF, 10.8% with overextended RCF, 35.7% with nonhomogeneous RCF, and 15.5% in teeth with untreated root canals. The rate of RCF teeth with procedural errors associated with PTED was 76.2%. There was no significant difference between sexes in apical periodontitis (P>0.05), which developed more frequently in teeth with procedural errors. CONCLUSIONS The overall prevalence of poor fillings (having at least 1 procedural error) among RCF teeth was high (54.1%) in this subpopulation. There is a substantial need to improve the technical quality of endodontic treatment.

Nocardiosis in a patient with pemphigus foliaceus treated with rituximab.

Rituximab is a chimeric human/murine monoclonal anti-CD20 antibody. This agent is an effective therapeutic option in severe types of pemphigus. However, rituximab may cause opportunistic infections if used in immunosuppressed patients. We reported a case of diffuse Nocardia infection following rituximab treatment in pemphigus foliaceus. Rheumatoid arthritis protocol applied in our patient. Rituximab was used at a dose of 1000 mg every 2 weeks. Because the disease was not adequately controlled, rituximab treatment was administered six times every 15 days. One week after the sixth dose of the rituximab, she presented lassitude and multiple palpable masses in soft tissue of the upper extremity. Thereafter, the aspirate culture of the abscess on the left shoulder was taken and confirmed to be disseminated nocardiosis. She was treated with linezolid and meropenem for 1 month; however, amikacin was added because the patient did not respond adequately to linezolid and meropenem therapy. The patient died of cardiac arrest because of her comorbidities. In this case, prolonged administration of rituximab therapy may have caused the development of nocardiosis. Therefore, all patients should have a sensible balance of risk and benefit, considering the use of rituximab.

Dentofacial traumatic injuries: A survey of knowledge and attitudes among emergency medicine physicians in Turkey.

BACKGROUND/AIM: Emergency department (ED) visits for dental issues are mostly related to traumatic injuries. The knowledge of ED physicians about the diagnosis and treatment of dentofacial injuries is crucial for prognosis. The aim of this study was to evaluate the attitude and knowledge as well as education and self-confidence levels of emergency medicine physicians in ED regarding the diagnosis and treatment of dentofacial traumatic injuries. MATERIAL AND METHODS: A total of 109 emergency medicine physicians participated in the study. Participants were residents and specialists who attended a national emergency medicine symposium held in Turkey. A questionnaire was distributed during the symposium relating to general data about physicians, their attitudes, basic knowledge, and confidence levels which were believed to be indicative of their capabilities in managing of traumatic dental and maxillofacial injuries. RESULTS: The questionnaire was answered by 109 physicians who were general practitioners (11%), emergency medicine residents (56.8%), and emergency medicine specialists (32.2%). The most experienced group of physicians were emergency medicine specialists. Regardless of the physicians' titles, dentofacial trauma knowledge levels of ED physicians were found to be insufficient. Having a dentist in the family (P < 0.01), the duration of emergency service experience (P = 0.04), and the age of the physicians (P < 0.001) were significantly related to the knowledge level. CONCLUSIONS: The majority of ED physicians had low knowledge regarding the diagnosis and treatment of dentofacial traumatic injuries. There is a need for education during and after medical training for ED physicians to provide appropriate primary management of dentofacial trauma.

Radiologic assessment of third molar tooth and spheno-occipital synchondrosis for age estimation: a multiple regression analysis study.

For forensic age estimation, radiographic assessment of third molar mineralization is important between 14 and 21 years which coincides with the legal age in most countries. The spheno-occipital synchondrosis (SOS) is an important growth site during development, and its use for age estimation is beneficial when combined with other markers. In this study, we aimed to develop a regression model to estimate and narrow the age range based on the radiologic assessment of third molar and SOS in a Turkish subpopulation. Panoramic radiographs and cone beam CT scans of 349 subjects (182 males, 167 females) with age between 8 and 25 were evaluated. Four-stage system was used to evaluate the fusion degree of SOS, and Demirjian's eight stages of development for calcification for third molars. The Pearson correlation indicated a strong positive relationship between age and third molar calcification for both sexes (r = 0.850 for females, r = 0.839 for males, P < 0.001) and also between age and SOS fusion for females (r = 0.814), but a moderate relationship was found for males (r = 0.599), P < 0.001). Based on the results obtained, an age determination formula using these scores was established.

Endodontic management of C-shaped root canal system of mandibular first molar by using a modified technique of self-adjusting file system.

AIM: C-shaped canal system is a seldom-found root canal anatomy which displays a challenge in all stages of endodontic treatment. According to the literature, this type of canal morphology is not a common finding in the mandibular first molar teeth. BACKGROUND: This case report presents endodontic management of a mandibular first molar with a C-shaped canal system. CASE REPORT: Root canal system was cleaned and shaped by nickel-titanium (NiTi) rotary instruments combined with self-adjusting file (SAF). Obturation was performed using warm, vertical condensation combined with the injection of warm gutta-percha. Follow-up examination 12 months later showed that the tooth was asymptomatic. The radiological findings presented no signs of periapical pathology. CLINICAL SIGNIFICANCE: The clinician must be aware of the occurence and complexity of C-shaped canals in mandibular first molar teeth to perform a successful root canal treatment. The supplementary use of SAF after application of rotary instruments in C-shaped root canals might be a promising approach in endodontic treatment of this type of canal morphology.

Evaluation of dentinal defect formation after root canal preparation with two reciprocating systems and hand instruments: an in vitro study.

The purpose of this study was to evaluate the presence of dentinal defects after root canal preparation with hand instruments and two different reciprocating instruments. Sixty freshly extracted mandibular incisor teeth were selected for this in vitro study. On the basis of root length, mesiodistal and buccolingual dimensions, the teeth were allocated into three identical experimental groups (n = 15) and one control group (n = 15). The teeth in the control group were left unprepared. The other groups were: stainless steel hand instruments, WaveOne® Primary instruments and RECIPROC® R25 instruments. The reciprocating instruments were used with a reciprocating gentle in-and-out motion in a torque-limited electric motor at the appropriate preset mode. Horizontal sections were made 3, 6 and 9 mm from the apex. Samples were stained with methylene blue and viewed through a stereomicroscope. The presence of dentinal defects (fractures, incomplete cracks and craze lines) and their locations were investigated by two endodontists. These data were analysed statistically by Fisher's exact and chi-square tests. No defects were observed in the unprepared group. All instruments caused dentinal defects, with no significant differences between the instrument systems. All experimental groups demonstrated significantly more defects at the 3-mm level in comparison with the unprepared group (p = 0.032). At the other levels, there was no significant difference between the experimental groups and the control group. The use of hand or reciprocating instruments could induce the formation of dentinal defects during root canal preparation.

Nail changes in patients receiving systemic isotretinoin therapy.

In this study, it was aimed to describe isotretinoin-induced nail changes and increase patients' treatment compliance. A total of 200 patients diagnosed with acne vulgaris were included in the study. 100 of the patients were started systemic isotretinoin treatment and 100 control patients were receiving topical acne treatment. Age and gender of all of the participants, duration of treatment, total doses per month, and type of nail changes were recorded. Patients with persistent nail changes were followed at the 3rd and 6th months after treatment. A total of 34 patients had nail changes in the isotretinoin group. These changes included onychoschizia (55.9%), leukonychia (11.8%), onychorexis (8.8%), median nail dystrophy (5.9%), pyogenic granulomas (5.9%), chronic paronychia and granulation tissue (5.9%), onycholysis (2.9%) and Beau's line (2.9%). The rate of nail changes in the isotretinoin group was significantly higher than in the topical treatment group (34% vs. 11%, p:0.001). Isotretinoin increases the risk of nail changes, primarily onychoschizia. The risk of developing nail changes is not associated with treatment duration but is associated with the total cumulative dose. Nail findings induced by isotretinoin are completely reversible.

Evaluation of Dermatology Life Quality Index, Depression-Anxiety-Stress Scores of Patients with Genital Dermatoses.

Background: Genital dermatoses contain a group of diseases that affect the skin of the genital area. Genital dermatoses are classified as venereal and nonvenereal. They can affect a patient's life quality and can cause depression, anxiety and stress. Aims: This study aimed to evaluate and compare the quality of life index, depression, stress and anxiety in patients with genital dermatoses. Materials and Methods: Patients admitted to the dermatology outpatient clinic with genital skin complaints between October 2020 and March 2021 were included. A questionnaire including demographic information, a 10-item dermatology life quality index (DLQI) and a 21-item depression anxiety stress score (DASS-21) was filled out by the patients and was calculated. Results: A total of 103 patients were included in this study. Seventy-seven (74.8%) were male and 26 (25.2%) were female. A total of 48.5% (n = 50) patients had venereal genital dermatoses, and 51.5% (n = 53) of the patients had nonvenereal genital dermatoses. In the venereal diseases, syphilis had the highest DLQI, depression, anxiety and stress score while in the nonvenereal diseases, scabies had the highest DLQI, depression, anxiety and stress score. In the nonvenereal group, the mean DLQI score, depression, anxiety and stress scores were statistically significantly higher than the venereal genital dermatoses group (P < 0.01, P = 0.04, P = 0.03 and P = 0.02). Conclusion: The quality of life of patients with genital dermatoses is often poor, with significant levels of depression, anxiety and stress. We believe that screening these patients with DLQI and DASS-21 scores at their first admission and follow-up will benefit dermatologists and patients.

The Efficiency of the BTR-Pen System in Removing Different Types of Broken Instruments from Root Canals and Its Effect on the Fracture Resistance of Roots.

The study aimed to evaluate the efficiency of the BTR-Pen system in removing different types of instrument fragments from root canals and to assess its effect on fracture resistance of the roots after the removal of the instruments. One hundred thirty human teeth were divided into 10 groups (2 control groups and 8 study groups) according to the localization and type of the fractured fragment as well as the retrieval techniques. Broken instruments were extracted either with BTR-Pen system loops or removed using solely ultrasonic tips. The success rate of instrument removal and consumed time were recorded. All the teeth were subjected to a load at a 1 mm/min rate in a universal testing machine for mechanical testing. The success of removing broken instruments using the BTR-Pen and ultrasonic was 86.7% and 83.3%, respectively (p > 0.05). When the time is compared, the BTR-Pen system (23.97 ± 8.35 min) showed similar results to that of the ultrasonic technique (24.1 ± 8.28 min) (p > 0.05). The BTR-Pen group required less force to fracture than the ultrasonic group (p = 0.024). In conclusion, the BTR-Pen and ultrasonic groups showed no significant difference in terms of the success rate and removal time. The roots that underwent instrument removal using the BTR-Pen system had less fracture resistance.

Prevalence, classification and dental treatment requirements of dens invaginatus by cone-beam computed tomography.

Background: This study aimed the evaluation of the prevalence, characteristics, types of dens invaginatus (DI) and co-observed dental anomalies to understand dental treatment requirements in anterior teeth that are susceptible to developmental anomalies by using cone-beam computed tomography (CBCT). Methods: In this retrospective study, the anterior teeth of 958 patients were evaluated by using CBCT for the presence of DI. The demographic features, types of DI and treatment requirements were also recorded. The association between sex and the presence of DI was evaluated using chi-squared test. Results: Seventy-three DI anomalies were detected in the anterior teeth of 49 patients (18 females, 31 males). The frequency of DI was 5.11% and the most frequently involved teeth were lateral (57.53%). Forty-six teeth were classified as Type I (63.01%), 24 as Type II (32.87%), and three as Type III (4.10%). Apical pathosis was found to be 20.54% in all DIs detected and accounted for all Type III and one-third of Type II. Conclusions: CBCT imaging can be effective in the detection of dental anomalies such as DI and planning for root canal therapy and surgical treatments. Prophylactic interventions might be possible to prevent apical pathosis with the data obtained from CBCT images.

Comparative Evaluation of Artifacts Originated by Four Different Post Materials Using Different CBCT Settings.

The aim of this study was to evaluate whether cone beam computed tomography (CBCT) images in the presence of four different post materials, obtained from different kVps with varying resolutions and varying metal artifact reduction (MAR) algorithms, differed in artifact estimation, and to compare tooth regions in terms of artifact value. MATERIALS AND METHODS: Forty premolar teeth were used in this study. Root canals were treated, and teeth were randomly distributed into four subgroups (n = 10) for the preparation of post materials: titanium, gold (Nordin), quartz fiber (Bisco DT Light), and glass fiber (Rely X). The CBCT images were taken with two different kVps, three different metal artifact reduction (MAR) algorithm options, and two different resolutions. For each protocol, the effective dose was calculated according to the dose area production (DAP) value. The standard analysis of variance technique and the Tukey multiple comparison adjustment method were used to assess interactions among material types, kVp, MAR, and voxel settings. RESULTS: More artifacts were found in the middle third than in the cervical third (p < 0.05). The mean value of artifacts was highest for gold (Nordin), 90 kVp, no MAR, and 100 voxel size. Glass or quartz fiber posts at low resolution, with high MAR and 96 kVp, originated fewer artifacts. Moreover, the use of 90 and 96 kVp with 200 voxel size and high MAR provided the least amount of radiation. CONCLUSION: The best setting for radiographic follow-up of post materials on the Planmeca ProMax is 96 kVp with low resolution and high MAR; this setting produced one of the lowest effective doses. CLINICAL SIGNIFICANCE: This study estimated the best scanning protocol by lowering the effective dose to a minimum level according to the "as low as reasonably achievable" principle, as well as assessing the tooth region and the post material generating the fewest artifacts, in order to prevent image interpretation challenges such as false-positive and false-negative results stemming from the deterioration of the visibility of the root canal due to perforation, fractures, and voids in the root canal region.

Effectiveness of Various Final Irrigation Techniques on Sealer Penetration in Curved Roots: A Confocal Laser Scanning Microscopy Study.

OBJECTIVE: To compare the efficacy of various techniques used for final irrigation on sealer penetration in the apical one-third of curved root canals. Material and Methods. Sixty-five freshly extracted maxillary first molar teeth with mesiobuccal roots having more than 20° of root curvature were used. The root canals were instrumented and randomly divided into four experimental groups and one control group. In the 4 experimental groups, 3 ml of 17% EDTA followed by 3 ml of 5.25% NaOCl was delivered with the use of the following protocols: Group 1: manual dynamic activation (MDA), Group 2: sonic irrigation (SI), Group 3: passive ultrasonic irrigation (PUI), and Group 4: conventional needle irrigation (CI). All teeth were obturated with gutta-percha and AH Plus sealer labeled with fluorescent dye. Transverse sections at 2 mm and 4 mm distance from the root apex were examined with the aid of confocal laser scanning microscopy. Total percentage (%) and maximum depth (µm) of sealer penetration were measured. RESULTS: All the experimental groups exhibited significantly higher penetration rates than the control group at both sections (p < 0.05). However, no significant differences were found in the penetration depth and percentage among the four experimental groups evaluated at both sections (p > 0.05). CONCLUSION: PUI, SI, and MDA did not significantly improve sealer penetration in the apical portion of curved root canals when compared to conventional needle irrigation.

Fracture strengths of endocrown restorations fabricated with different preparation depths and CAD/CAM materials.

The objectives of this study were to compare the fracture strength of endocrown restorations fabricated with different preparation depth and various CAD/CAM ceramics, and to assess the fracture types. Endodontically treated 100 extracted human permanent maxillary centrals were divided into two preparation depth groups as short (S: 3-mm-deep) and long (L: 6-mm-deep), then five ceramic subgroups, namely: feldspathic-ceramic (Vita Mark II-VM2), lithium-disilicate glass-ceramic (IPS e.max CAD-E.max), resin-ceramic (LAVA Ultimate-LU), polymer infiltrated ceramic (Vita Enamic-VE) and monoblock zirconia (inCoris TZI-TZI) (n=10/subgroup). The endocrowns were fabricated by CAD/CAM and were cemented with resin cement (RelyX U200). The teeth were thermally cycled (5,000cycles) and fracture tests were performed at 45º angle to the teeth. The data were statistically analyzed (Kruskal-Wallis, Mann Whitney U), failure modes were evaluated with stereomicroscopy. Zirconia group provided the statistically highest fracture strength, but also exhibited non-repairable failures. Preparation depth has an effect on the fracture strength only for feldspathic ceramic.

Evaluation of Dentin Defect Formation during Retreatment with Hand and Rotary Instruments: A Micro-CT Study.

The purpose of this study was to compare the incidence and longitudinal propagation of dentin defects after gutta-percha removal with hand and rotary instruments using microcomputed tomography. Twenty mandibular incisors were prepared using the balanced-force technique and scanned in a 19.9 µm resolution. Following filling with the lateral compaction technique, gutta-percha was removed with ProTaper Universal Retreatment (PTUR) or hand instruments. After rescanning, a total of 24,120 cross-sectional images were analyzed. The numbers, types, and longitudinal length changes of defects were recorded. Defects were observed in 36.90% of the cross sections. A total of 73 defects were comprised of 87.67% craze lines, 2.73% partial cracks, and 9.58% fractures. No significant difference in terms of new defect formation was detected between the retreatment groups. The apical and middle portions of the roots had more dentin defects than the coronal portions. Defects in three roots of the PTUR instrument group increased in length. Under the conditions of this in vitro study, gutta-percha removal seemed to not increase the incidence of dentin defect formation, but the longitudinal defect propagation finding suggests possible cumulative dentinal damage due to additional endodontic procedures. Hand and rotary instrumentation techniques caused similar dentin defect formation during root canal retreatment.

Contrast-to-noise ratio with different settings in a CBCT machine in presence of different root-end filling materials: an in vitro study.

OBJECTIVES: To compare the contrast-to-noise ratio (CNR) of multiple acquisition settings for four types of retrograde filling materials in CBCT images taken for endodontic surgery follow-up. METHODS: 20 maxillary central incisors were endodontically treated and obturated with 4 different root-end filling materials: amalgam, mineral trioxide aggregate, SuperEBA(™) (Harry J Bosworth Company, Skokie, IL) and Biodentine™ (Septodont, Saint-Maur-des-Faussés, France). Teeth were placed in a skull and scanned, one by one, with the Planmeca ProMax(®) 3D Max (Planmeca, Helsinki, Finland); at different voltages: 66, 76, 84 and 96 kVp; with low, normal and high resolution and high definition (HD); with and without metal artefact reduction (MAR). Images were analyzed using ImageJ software (National Institutes of Health, Bethesda, MD) to calculate the CNR. The dose-area product was registered, and the effective dose calculated. RESULTS: No statistically significant difference was noted between the four materials. 84 and 96 kVp with low resolution and the use of MAR-generated images that have statistically better CNR than 66 and 76 kVp with HD, normal and high resolutions and without MAR. The use of low resolution also generated the smallest value of effective dose. CONCLUSIONS: The best setting for radiographic follow-up in an endodontic surgery with retrograde filling on the Planmeca ProMax is 96 kVp with low resolution and high MAR; this setting produced one of the lowest effective doses.

Evaluation and Reduction of Artifacts Generated by 4 Different Root-end Filling Materials by Using Multiple Cone-beam Computed Tomography Imaging Settings.

INTRODUCTION: After endodontic surgery, radiographic assessment is the method of choice to monitor bone defect healing. Cone-beam computed tomography scans are useful to check and identify the reasons of failure of surgical intervention or confirm healing; however, the artifact generated by some root-end filling material might compromise this task. The objective of the study was to compare the amount of artifacts generated by 4 root-end filling materials and to test multiple exposure settings used with these materials, when the effective dose generated by each protocol was taken into consideration. METHODS: Twenty central incisors were endodontically treated with retrograde obturation by using amalgam, Biodentine, MTA, and Super-EBA (5 of each). They were placed in a skull with soft tissue simulation and scanned by using the Planmeca Promax Max with different kilovolt peaks (kVp): 66, 76, 84, and 96 with and without the use of metal artifact reduction (MAR) algorithm and with low, normal, and high resolution and high definition. The Dose Area Product was registered, and the effective dose was calculated. RESULTS: Amalgam generated the highest amount of artifacts, whereas MAR and low resolution created fewer artifacts than other settings. The artifacts were also reduced with 96 kVp. The effective dose calculated with low resolution was remarkably lower than other resolutions. CONCLUSIONS: When used as root-end filling material, Biodentine, MTA, and Super-EBA generated fewer artifacts than amalgam. The use of 96 kVp with MAR and low resolution also reduced artifacts on the image and at the same time generated the lowest effective dose.

Use of cone-beam computed tomography and three-dimensional modeling for assessment of anomalous pulp canal configuration: a case report.

Three-dimensional (3D) reconstruction of cone-beam computed tomography (CBCT) scans appears to be a valuable method for assessing pulp canal configuration. The aim of this report is to describe endodontic treatment of a mandibular second premolar with aberrant pulp canal morphology detected by CBCT and confirmed by 3D modeling. An accessory canal was suspected during endodontic treatment of the mandibular left second premolar in a 21 year old woman with a chief complaint of pulsating pain. Axial cross-sectional CBCT scans revealed that the pulp canal divided into mesiobuccal, lingual, and buccal canals in the middle third and ended as four separate foramina. 3D modeling confirmed the anomalous configuration of the fused root with a deep lingual groove. Endodontic treatment of the tooth was completed in two appointments. The root canals were obturated using lateral compaction of gutta-percha and root canal sealer. The tooth remained asymptomatic and did not develop periapical pathology until 12 months postoperatively. CBCT and 3D modeling enable preoperative evaluation of aberrant root canal systems and facilitate endodontic treatment.