Canal Volume Research Articles

Multipopulation evaluation of the internal morphology of mandibular first premolars from different South American countries. A micro-computed tomography study

ObjectiveTo evaluate and compare several anatomical parameters of mandibular first premolars from individuals from different Latin American countries using micro-computed tomography. DesignFive hundred extracted mandibular first premolars from Brazilian, Argentinian, Chilean, Colombian, and Ecuadorian individuals were scanned using micro-computed tomography (n = 100 teeth/country). Root canal configurations were classified according to established parameters. Analyses also included: canal volume and surface area, structure model index, distances from the apical foramen to the root apex or the cementoenamel junction, major/minor apical canal diameters, canal orifice shape, and prevalence of ramifications. ResultsA single root was the most common anatomy in all countries (range, 97%−100%). Vertucci’s type-I canal was the most frequent configuration (range, 36%−66%), followed by C-shaped and type-V canals. The oval-shaped canal orifice was the most predominant in all countries (range, 34%−58%), followed by the circular shape (range, 16%−47%). C-shaped canals occurred in all subpopulations (range, 14%−26%), always associated with radicular grooves. Ranges for canal ramifications were as follows: accessory canals, 36%−73%; lateral canals, 4%−12%; and apical delta, 4%−14% of the teeth. Many anatomic parameters differed significantly between countries (P < .05). ConclusionsVertucci’s types-I and -V, and C-shaped canals were the most prevalent configurations in the subpopulations investigated. Accessory canals and several complex anatomies were found, with some significantly different frequencies between countries.

Efficacy of OLIF combined with pedicle screw internal fixation for lumbar spinal stenosis on spinal canal changes before and after surgery

PurposeThe purpose of the study was to evaluate the efficacy of OLIF combined with pedicle screw internal fixation in the treatment of lumbar spinal stenosis by assessing the changes in spinal canal before and after surgery.MethodsIn this retrospective study, we included sixteen patients who underwent a combination of single-segment OLIF and pedicle screw internal fixation for the treatment of lumbar spinal stenosis at the Affiliated Hospital of Jiangxi University of Chinese Medicine between February 2018 and August 2022. The patients' pre- and post-operative data were compared. Intraoperative bleeding, duration of surgery, visual analogue score (VAS), Oswestry Disability Index (ODI), disc height (DH), cross-sectional area of vertebral canal (CSAVC), cross-sectional area of dural sac (CSADS), cross-sectional area of intervertebral foramen (CSAIF), spinal canal volume (SCV), spinal canal volume expansion rate, lumbar lordosis, and sagittal vertical axis were observed and recorded. The efficacy of OLIF combined with pedicle screw internal fixation for lumbar spinal stenosis on spinal canal changes before and after surgery was summarized.ResultsThe results showed that OLIF combined with pedicle screw internal fixation effectively restored disc height and increased the cross-sectional area of the spinal canal. It also had an indirect decompression effect. The intraoperative bleeding and duration of surgery were within acceptable ranges. The VAS and ODI scores significantly improved after surgery, indicating a reduction in pain and improvement in functional disability. The CSAVC, CSADS, CSAIF, SCV, and spinal canal volume expansion rate were all increased postoperatively. Additionally, there was improvement in lumbar lordosis and sagittal vertical axis. We conducted a follow-up of all patients at 1 year after the surgery. The results revealed that the parameter values at 1 year post-surgery showed varying degrees of decrease or increase compared to the immediate postoperative values. However, these values remained statistically significant when compared to the preoperative parameter values (P < 0.05).ConclusionsOLIF combined with pedicle screw internal fixation effectively restores disc height and increases the cross-sectional area of the vertebral canal in patients with LSS, reflecting the indirect decompression effect. Measuring parameters such as DH, CSAVC, CSADS, CSAIF, SCV, and SCV expansion rate before and after surgery provides valuable information for evaluating the efficacy and functional recovery of the lumbar spine in LSS patients treated with OLIF surgery.

Comparative Evaluation of the Canal Shaping Ability, Pericervical Dentin Preservation, and Smear Layer Removal of TruNatomy, WaveOne Gold, and ProTaper Ultimate—An Ex Vivo Study in Human Teeth

IntroductionInnovative file systems have been recently introduced, claiming improved effectiveness and superior ability to preserve the tooth structure, still allowing an efficient preparation and disinfection up to the apical region. Regardless, few data are available on the comparative effectiveness of the most recently developed systems. Thus, this ex vivo study aimed to comparatively evaluate, for the first time, the functionality of WaveOne Gold (WOG), TruNatomy (TN), and ProTaper Ultimate (PU) file systems regarding canal shaping, dentin preservation, and smear layer removal ability. MethodsHuman maxillary incisors were randomly divided for instrumentation with one of the assayed systems. Canal shaping ability and pericervical dentin preservation were characterized through microtomographic evaluation and morphometric assessment (n = 15). Smear layer removal ability was evaluated by scanning electron microscopy (SEM) (n = 6). ResultsTN and PU presented the lowest canal volume variation upon instrumentation, found to be significantly lower than that attained with WOG (P < .05). Pericervical dentin was reduced in all groups upon instrumentation, with TN evidencing the highest preservation, quantitatively similar to PU, and significantly higher than that attained with WOG (P < .05). SEM imaging revealed the presence of scattered remnants of the smear layer and partially opened dentinal tubules at the apical portion, with no significant differences between systems. ConclusionsTN and PU allowed for the highest tissue preservation, reporting the lowest volume variation and the highest preservation of the pericervical dentin. None of the assessed systems provided a complete removal of the smear layer in the apical region.

Modified posterior osteotomy for osteoporotic vertebral collapse with neurological dysfunction in thoracolumbar spine: a preliminary study

ObjectiveThe risk of osteoporotic vertebral collapse (OVC) associated with delayed neurological dysfunction (DND) is substantial, and performing surgery for this condition in elderly patients presents challenges. The focus of the current research is on simplifying surgical procedures while maintaining their effectiveness. This study was designed to contribute clinical data supporting the use of modified posterior osteotomy for treating thoracolumbar OVC with DND. The study compares perioperative clinical parameters, imaging data characteristics, and changes in efficacy outcome indicators to provide evidence for the advancement of this technique.MethodsA total of 12 patients diagnosed with osteoporotic vertebral collapse and neurological dysfunction were included in the study. All patients underwent modified posterior osteotomy. Data regarding perioperative and radiological parameters as well as complications such as surgery duration, blood loss, ASIA grade, VAS, ODI, regional kyphosis angle (RKA), anterior vertebral height ratio (AVHr), and spinal canal clearance ratio (SCCr), were collected retrospectively. These parameters were then analysed to evaluate the clinical efficacy and safety of the modified posterior osteotomy technique.ResultsA total of 12 patients were included in the study, with a mean age of 65.5 ± 9.7 years. The average follow-up period was 29.4 ± 5.0 months. The mean operative blood loss was 483.3 ± 142.0 ml, and the average operative time was 3.7 ± 0.7 h. The visual analogue scale (VAS) score decreased from a preoperative value of 5.8 ± 0.7 to a final follow-up value of 1.3 ± 0.8 (P < 0.05), indicating a significant improvement in pain. The ODI decreased from 65.2 ± 6.0 before surgery to 20.5 ± 7.0, indicating a decrease in disability, and the postoperative neurological function showed a significant improvement. Correction of the RKA was observed, with the angle changing from 35.8 ± 10.8° before surgery to 20.0 ± 3.5° after surgery and to 22.5 ± 3.1° at the final follow-up. Similarly, correction of the AVHr was observed, with the height changing from 39.3 ± 18.0 to 63.0 ± 14.3 after surgery and to 53.9 ± 8.9 at the final follow-up. Correction of the SCCr was also observed, with the ratio changing from 54.9 ± 5.4 to 68.1 ± 5.3 after surgery and to 68.68 ± 6.76 at the final follow-up.ConclusionsPosterior modified osteotomy is an effective treatment for thoracolumbar osteoporotic fractures with OVC combined with DND. It can significantly preserve vertebral height, increase vertebral canal volume, correct kyphotic angle, and improve postoperative neurological function. The simplified osteotomy also offers advantages in terms of operating time, blood loss, postoperative VAS score, and improvement in lumbar function.

Assessment of the root filling volume in C-shaped root canal on cone-beam CT and micro-CT in relation to nano-CT.

To assess the observed volume of filled C-shaped root canals from different CBCT and micro-CT having nano-CT as a reference. Twelve extracted mandibular molars with C-shaped root canals were endodontically treated using Reciproc Blue R25 (VDW GMBH, Munich, Germany) in a reciprocating system and filled with gutta-percha (Dentsply Maillefer) and AH Plus sealer (Dentsply DeTrey, Konstanz, Germany). CBCT scans were performed using 3 units-3D Accuitomo 170 (J. Morita, Kyoto, Japan), ProMax 3D Max (Planmeca, Helsinki, Finland), and NewTom VGi EVO (Cefla QR, Verona, Italy)-at two resolution modes: standard and high. Micro-CT and nano-CT scans were also obtained. The volume of all filled C-shaped root canals was obtained using CTAn software (Bruker, Kontich, Belgium), and the blooming artifact, in relation to nano-CT volume, was calculated. The data were evaluated by the Bland-Altman plots and ANOVA two-way for repeated measures (α = 0.05). All CBCT units and micro-CT showed significantly larger observed volume of root canal filling when compared to nano-CT. The blooming artifact of root canal filling in standard resolution was significantly larger than that in high resolution (p < 0.05) in all CBCT units. Endodontic filling material with AH Plus sealer causes blooming artifacts in CBCT units and micro-CT. Considering the anatomical complexity of C-shaped root canals and the challenges associated with endodontic treatment, CBCT is frequently recommended for follow-up evaluations. However, the presence of endodontic filling material can result in blooming artifacts that may potentially impact the accurate diagnosis of endodontic complications.

Numerical simulation and optimization of a circular open channel for fish farming using Computational Fluid Dynamics (CFD)

Open canals are one of the most common and cost-effective methods in water supply networks; they are widely used in different industries such as agriculture, water and sewage treatment, urban drainage, pisciculture and water parks. Due to global warming, the demand in clean energy to replace fossil fuels has caused using water turbines in riverbeds and aqueducts to be important. On this basis, optimizing key parameters such as flow motion and canal turbulence is crucial to reduce breakdowns while designing canals. In fact, the inappropriate adjustment of velocity and pressure within the canals may lead to the system failure: imbalance between inlet and outlet will increase the water level and the pressure on canal walls thus, leading to breakdown. In this paper, a circular open canal was designed for a pisciculture system. The velocity and height of the water canal is controlled by the canal inlet and outlet system and the water flows continuously inside the canal. By keeping the canal water volume constant in any time and the flow motion with constant velocity, the system makes the fishes feel infinite movement. Furthermore, the water particles and impurities (e.g., food and fish feces) are removed by the outlet from the canal bottom, transferred to the filtration system, and returned to the fish farm by the canal inlet after the filtration procedure; the mentioned technique causes the water canal to be kept at its optimal level. Computational Fluid Dynamics (CFD) has been used to simulate the canal flow. Solving the Navier-Stokes equations numerically and assuming incompressible, unsteady, and two-phase flow, the parameters of the canal flow were extracted. Also, by mounting the system outlet along the path of water movement, greatly reduces the adverse effects of the outlet suction force on the canal main flow. Moreover, by dividing the canal inlet with guide vanes, the inlet has been modified for the entrance of the clean water simultaneously with the distribution of the inlet flow to several smaller flows in order to make the canal water continue to move continuously without any turbulence.

Root Canal Preparation of a Commercial Artificial Tooth versus Natural Tooth—A MicroCT Study

This study aimed to evaluate by microCT the preparation of the artificial teeth (ATs), TrueTooth®, versus natural teeth (NTs): (1) the time and number of pecking movements needed for preparation; (2) the root canal volume increase; (3) if the pulp-colored medium has any effect on the 3D analysis. Material and Methods: Artificial and natural maxillary molars were used. Fourteen AT distobuccal canals and fourteen NT buccal canals were used for the first and second aim and fourteen AT mesiobuccal canals for the third aim. Results: No statistically significant differences were observed regarding the time and number of pecking movements (p &gt; 0.05); for the root canal volume increase, a statistically significant difference was observed (p &lt; 0.05) with a higher mean value for NTs; however, in the group of ATs, there was a volume decrease in three cases. The AT mesiobuccal root canal mean volume increase was also negative. Conclusions: There are no differences between the time and number of pecking movements between NTs and ATs, so TrueTooth® can potentially be used in endodontic training. The volume increase between ATs and NTs was higher in NTs. However, some samples showed negative values, also seen in the AT mesiobuccal canal, confirming that the pulp-colored medium has an effect on the 3D analysis.

How cervical curvature changes after ACAF and ACDF: a radiological retrospective study.

To assess changes in cervical curvature and demonstrate the feasibility of using ACAF technology to restore lordosis, imaging data from patients undergoing multilevel ACAF and ACDF surgeries were retrospectively analyzed. Forty-seven patients receiving multilevel ACAF and ACDF were included in the study. Total cervical curvature and anterior, middle, and posterior column curvature, spinal canal diameter, cervical range of motion, and surgical complications were measured and analyzed by non-parametric or chi-square tests before and after surgery. The Spearman correlation between imaging data was analyzed. Compared with ACDF, the operation time of the ACAF group was longer, the cervical motion was larger, the median and change value of the middle column curvature was larger, and the change value of the posterior column curvature was smaller (P < 0.05). The postoperative differences in cervical lordosis angle, vertebral canal diameter, and middle and posterior column curvature in the ACAF group were significantly greater than those in the ACDF group (p = 0.015). The expansion of vertebral canal diameter was significantly correlated with the difference in curvature between the middle and posterior columns (r = 0.523, P < 0.01), and the curvature of the anterior column was correlated with that of the middle and posterior columns (P < 0.05). The curvature change of the anterior column is closely related to the curvature change of the middle column and the posterior column. Compared with ACDF, ACAF expands the diameter and volume of the spinal canal by increasing the curvature of the middle column and reducing the anterior movement of the posterior column.

Intraradicular Dentinal Changes Following Fiber Postremoval: Micro-computed Tomography Analysis

Abstract Context: Excessive dentine wear during postremoval can occur due to the adhesion between the cement and the post. Aim: The aim is to evaluate dentine wear and microcrack occurrence following the removal of intraradicular fiberglass posts that were previously cemented with two types of resin cement. Methods: Distal roots (n = 38) of lower molars were instrumented, filled, prepared for intraradicular postinstallation, and divided into two groups according to the cement used for the posts: RelyX ARC or RelyX U200. The posts were removed through abrasion using ultrasonic diamond tips, after which the degrees of dentine wear (volume/mm3) and microcrack formation were assessed using microcomputed tomographic imaging. Statistical Analysis Used: The Mann–Whitney U (P ≤ 0.05) and Chi-squared tests (P ≤ 0.05) were used. Results: After the removal of the posts, no statistically significant difference in root canal volume or microcrack occurrence was observed between the groups (P &gt; 0.05). The procedure produced significant dentine wear regardless of the type of cement used (P &lt; 0.05). Conclusions: The removal of fiberglass posts caused extensive dentine wear but did not influence microcrack occurrence. The type of resin cement used did not affect the dentine loss or microcrack appearance that resulted from fiberglass postremoval.

Comparative Evaluation of a Dynamic Navigation System versus a Three-dimensional Microscope in Retrieving Separated Endodontic Files: An In Vitro Study

IntroductionThis study aimed to compare the effectiveness of a dynamic navigation system and a three-dimensional microscope in retrieving broken rotary Nickel-Titanium files when using trepan burs and the extractor system. Materials and MethodsThirty maxillary first bicuspids with 60 separate roots were split into 2 comparable groups based on a comprehensive cone beam computed tomography analysis of the root length and curvature. After standardized access opening, glide paths, and patency attainment with the K file (sizes 10 and 15), the teeth were arranged on 3D models (three per quadrant, six per model). Subsequently, controlled-memory heat-treated Nickel-Titanium rotary files (#25/0.04) were notched 4 mm from the tips and fractured at the apical third of the roots. The C-FR1 Endo file removal system was employed under both guidance to retrieve the fragments, and the success rate, canal aberration, treatment time, and volumetric changes were measured. The statistical analysis was performed using IBM SPSS software at a significance level of 0.05. ResultsThe microscope-guided group had a higher success rate than the dynamic navigation system guidance, but the difference was insignificant (P > .05). In addition, the microscope-guided drills resulted in a substantially lower proportion of canal aberration, shorter time to retrieve the fragments and less change in the root canal volume (P < .05). ConclusionAlthough dynamically guided trephining with the extractor can retrieve separated instruments, it is inferior to three-dimensional microscope guidance regarding treatment time, procedural errors, and volume change.

Shaping ability of BlueShaper, TruNatomy, DC Taper and HyFlex EDM in long oval canals: An ex vivo study.

This study evaluated and compared the shaping ability of four rotary instrument systems in long-oval root canals using microcomputed tomographic (micro-CT) evaluation. Currently, there is no data available on the canal shaping abilities of BlueShaper and DC Taper instruments. Sixty-four single-rooted mandibular premolars were matched based on similar root canal morphologic features as determined by (micro-CT) and randomly assigned to 1 of 4 experimental groups (n = 16) according to the instrument system used: BlueShaper, TruNatomy, DC Taper and HyFlex EDM One File. Changes in the root canal surface and volume, remaining dentine thickness, and number of prepared areas were assessed. No significant differences were found amongst the four instrument systems for the parameters evaluated (p > .05). There was a significant reduction in the number of unprepared areas and the remaining dentine thickness after each increase in size of the instruments tested (p < .05). The four instrument systems perform similarly in long oval root canals. Although none could prepare all canal walls, larger preparations incorporated significantly more surfaces in the final shape.

Comparison of the Effects of WaveOne Gold, TruNatomy, and Conventional Hand Files on Remaining Dentin Volume in the Coronal Part of the Root and Preparation Efficiency in Mandibular Molars

IntroductionThe use of file systems that work with different principles in root canal treatment is becoming widespread. The aim of this study was to evaluate the remaining dentine volume in the coronal region of the root and preparation efficiency after the use of conventional hand files, WaveOne Gold; which works with reciprocating motion, and TruNatomy; which works with rotational motion in the root canal treatment of mandibular molar teeth. MethodsAll canals of permanent mandibular molars (n = 36) were used. Root canals in each group (n = 12) were prepared with conventional hand files, WaveOne Gold, and TruNatomy. The three-dimensional images were evaluated for remaining dentine volume in the coronal two-millimeter region of the root and change in volume of the entire root canal space. ResultsThere was no statistically significant difference between the groups in terms of mean differences pre and postpreparation (P > .05). The mean differences after preparation were observed the most in the WaveOne Gold group and the least in the TruNatomy group in the coronal two-millimeter region of the root and entire canal volume, but the differences were not significant (P > .05, P > .05, respectively). ConclusionsConventional hand files, WaveOne Gold working with reciprocating motion, and TruNatomy working with rotational motion, which are the file systems used in the study, are not superior to each other in terms of remaining dentin volume in the coronal two-millimeter region of the root and preparation efficiency in the entire root canal space in mandibular molars.

Endoscopic dissection of the infraorbital canal in patients with sinonasal inverted papilloma

Intrоduction. Sinonasal papilloma is a benign tumor. The standard treatment for sinonasal inverted papilloma (SIP) is surgical intervention. The tumor is located primarily in the maxillary sinus (50.9 %). Sinonasal inverted papilloma originated from the maxillary sinus has aggressive characteristics and can dislodge local anatomical structures, infraorbital canal in particular.Aim. To present a descriptive characteristic of structural changes in the infraorbital canal during SIP growth and determine the optimal volume of canal dissection.Materials and methods. A retrospective study of patients with SIP was performed. From the total cohort (n = 37), 15 patients with primary localization of sinonasal inverted papilloma in the maxillary sinus were selected. In all cases, the same diagnostic algorithm was used. Separately, evaluation of infraorbital canal anatomy based on preoperative analysis of computed tomography of the paranasal sinuses and intraoperative endoscopic exam was performed. Surgical strategy used in all cases consisted of endoscopic SIP tissue removal, total resection of the mucoperiosteum and subperiosteal dissection of all walls of the maxillary sinus using a bur. During surgery material was collected for control histological examination.Results. In 20 % of cases, changes in the walls of the infraorbital canal in the form of hyperostosis, erosion and dehiscence were observed. In 13.3 % of cases, growth of sinonasal inverted papilloma caused distortions in the structure of infraorbital canal walls. In all cases, computed tomography data showed the same results as intraoperative endoscopic visualization. For removal of the lesion and pathologically changed walls of the infraorbital canal, transnasal endoscopic partial maxillectomies (type 3 or 4) were performed. Follow-up duration varied between 1 and 5 years, mean follow-up duration was 3 years. SIP resection was effective in all patients, no recurrences were observed.Conclusion. For SIPs growing in the maxillary sinus, condition of the infraorbital canal must be of special interest. The study showed the effectiveness and flexibility of the surgical strategy consisting of the combination of total mucoperiosteum resection with subperiosteal dissection of all walls of the maxillary sinus.

Age-related changes in the morphology of the root canal system of mandibular first molars: a micro-CT study.

This study aimed to evaluate changes on root canal morphology in patients with different ages using micro-CT technology. Mandibular first molars (n = 150) were scanned at a pixel size of 13.68µm, categorized into 3 groups according to patient's age and analyzed regarding configuration, orifices, apical foramina, root length, canal volume, and surface area. Morphological 2D and 3D parameters were evaluated in distal roots with Type I configuration (n = 109) as well as the morphology of isthmuses Types I and III in 68 mesial roots. One-way ANOVA post hoc Tukey and Kruskal-Wallis tests were used for statistical analyses (α = 5%). A great variation in the canal configuration was found. No difference was observed in roots' length (p > 0.05). Canal volume reduced with age (p < 0.05), while surface area increased (p < 0.05) in patients ≤ 30years. There was no difference in canal/root length, area, and from foramen to the apex in distal roots with Type I configuration (p > 0.05), but 2D and 3D parameters significantly decreased with age (p < 0.05). Overall, the diameter of the isthmuses' roof reduced with age (p < 0.05). In patients ≥ 31years with Type III isthmus the distance from the isthmus floor to the foramen of the mesiolingual canal also decreased (p < 0.05). Overall, the internal morphology of the mesial roots of mandibular first molars was more affected by aging than distal canals. The most relevant tested parameter that significantly reduced in both roots was the volume of the root canal systems. A detailed evaluation of fine anatomical aspects of the root canal system of mandibular first molars of patients with different ages showed that the internal morphology of mesial roots is more affected by aging than distal canals.

High Frequency Tympanometry in Early Infancy and Its Effect on Oto Acoustic Emissions.

The present study was conducted to study the benefit of high frequency tympanometry (HFT) in detecting middle ear pathologies in infants. This study also aims to find the effect of middle ear diseases on absent otoacoustic emissions (OAE). Our study was a prospective study which included 123 healthy neonates below 1 month of age. The babies were referred for the new born hearing screening programme. They were subjected to DPOAE followed by tympanometry with a 1000z probe tone (HFT). The study was approved by the institutions ethical committee. "Present" OAE result was obtained for 202 ears, while "absent" OAE result was obtained for 44 ears. High frequency tympanometry was also performed on all the participants, where a normal tympanogram was obtained in 170 ears and 76 ears showed an abnormal tympanogram. The following parameters were studied: peak pressure, ear canal volume and compliance. Descriptive statistics were obtained for the same. Association of OAE with HFT was studied. Out of the 44 ears with refer OAE, 34 ears had an abnormal tympanogram and among 202 ears with a present OAE, 160 ears had a normal tympanometric peak indicating a sensitivity and specificity of 77.3% and 79.2% respectively. High frequency tympanometry not only helps in early detection of middle ear pathologies but also to find the effect of middle ear diseases on absent otoacoustic emissions.

Does the activation of root canal dressings improve their filling quality on teeth with simulated internal root resorption?

This study aims to evaluate, by micro-computed tomography, the filling capacity of two root canal dressings (RCD) - Bio-C Temp and Ultracal - after different activation protocols in teeth with simulated internal root resorption. Eighty single-rooted bovine teeth were sectioned in the cervical portion, standardizing the roots at 16 mm. Then, the canals were prepared by the apex-crown technique until instrument #80 using 2mL of 2.5% sodium hypochlorite solution at each instrument change. Afterward, the roots were sectioned longitudinally, and internal root resorptions were simulated using a diamond bur 1016 at 5 mm from the root apex. Hemiroots were joined and fixed with cyanoacrylate, scanned in micro-computed tomography (micro-CT) to assess total canal volume and simulated internal resorption, and then divided by stratified randomization into experimental groups according to RCD and method of activation (n = 10): Ultracal/Syringe; Ultracal/PUI, Ultracal/XP Endo Finisher, Ultracal Easy Clean, Bio-C Temp/Syringe, Bio-C Temp/PUI, Bio-C Temp/XP Endo Finisher and Bio-C/Easy Clean. Another scanning was performed to assess the volume of voids after RCD activation methods. The ANOVA and Tukey tests compared the activation methods. Student's T-test compared the RCDs within each activation method. Initial root canal volume values were similar for all groups (P &gt; 0.05). There was no difference between activation protocols (P &gt; 0.05). Higher volumes of void spaces were observed for Bio-C Temp compared to Ultracal after all activation methods (P &lt; 0.05), except for Easy Clean (P &gt; 0.05). Due to this, it can be concluded that the agitation methods tested for the Bio-C Temp and Ultracal pastes did not improve the filling of bovine teeth with simulated internal root resorption.&#x0D;

Inter-rater agreement between 13 otolaryngologists to diagnose otitis media in Aboriginal and Torres Strait Islander children using a telehealth approach.

Telehealth programs are important to deliver otolaryngology services for Aboriginal and Torres Strait Islander children living in rural and remote areas, where distance and access to specialists is a critical factor. To evaluate the inter-rater agreement and value of increasing levels of clinical data (otoscopy with or without audiometry and in-field nurse impressions) to diagnose otitis media using a telehealth approach. Blinded, inter-rater reliability study. Ear health and hearing assessments collected from a statewide telehealth program for Indigenous children living in rural and remote areas of Queensland, Australia. Thirteen board-certified otolaryngologists independently reviewed 80 telehealth assessments from 65 Indigenous children (mean age 5.7±3.1 years, 33.8% female). Raters were provided increasing tiers of clinical data to assess concordance to the reference standard diagnosis: Tier A) otoscopic images alone, Tier B) otoscopic images plus tympanometry and category of hearing loss, and Tier C) as B plus static compliance, canal volume, pure-tone audiometry, and nurse impressions (otoscopic findings and presumed diagnosis). For each tier, raters were asked to determine which of the four diagnostic categories applied: normal aerated ear, acute otitis media (AOM), otitis media with effusion (OME), and chronic otitis media (COM). Proportion of agreement to the reference standard, prevalence-and-bias adjusted κ coefficients, mean difference in accuracy estimates between each tier of clinical data. Accuracy between raters and the reference standard increased with increased provision of clinical data (Tier A: 65% (95%CI: 63-68%), κ=0.53 (95%CI: 0.48-0.57); Tier B: 77% (95%CI: 74-79%), 0.68 (95%CI: 0.65-0.72); C: 85% (95%CI: 82-87%), 0.79 (95%CI: 0.76-0.82)). Classification accuracy significantly improved between Tier A to B (mean difference:12%, p<0.001) and between Tier B to C (mean difference: 8%, p<0.001). The largest improvement in classification accuracy was observed between Tier A and C (mean difference: 20%, p<0.001). Inter-rater agreement similarly improved with increasing provision of clinical data. There is substantial agreement between otolaryngologists to diagnose ear disease using electronically stored clinical data collected from telehealth assessments. The addition of audiometry, tympanometry and nurse impressions significantly improved expert accuracy and inter-rater agreement, compared to reviewing otoscopic images alone.

Shaping ability of WaveOne Gold and OneReci by using two apical sizes: a micro-computed tomographic assessment.

OneReci (MicroMega, Besançon, France) is a recently introduced single-file reciprocating system with scarce information revealed on its shaping ability. This study aimed to compare the shaping abilities of OneReci and a well-documented single-file reciprocating system WaveOne Gold (WOG; Dentsply Maillefer, Ballaigues, Switzerland) and evaluate the effect of increased apical enlargement on the preparation quality, using micro-computed tomography (micro-CT). After an initial micro-CT scanning, twenty mesial root canals of mandibular molars were anatomically matched. The canals were assigned to two experimental groups (n=10), using OneReci or WOG in different canals of the same root. The glide paths were created, and root canals were prepared twice, using size 25 and 35 instruments of the systems, respectively. The specimens were scanned with micro-CT after each preparation. The increase in canal volume, amount of dentin removal, unprepared root canal surface, canal transportation, centering ratio and preparation times were assessed. The data were analysed with independent sample t-tests, variance analyses, Friedman and Mann-Whitney U tests. The significance level was set at 5%. Each preparation increased the canal volume and dentin removal while decreasing the unprepared root surface. The difference between the systems became significant after preparation with size 35 instruments (p<0.05). Regarding canal transportation and centering ratio, the difference was insignificant (p>0.05). The first preparation step (glide path + size 25 instrument) was significantly faster in the OneReci group (p<0.05). Preparation with size 25 instruments of the systems appeared to be safe with similar shaping performances. Larger apical preparation promoted significantly higher dentin removal, volume increase, and prepared surface area in WOG.

Influence of brushing motions on the shaping of oval canals by rotary and reciprocating instruments.

The effects of brushing on shaping with three different instruments were assessed in oval canals. Mandibular incisors were assigned to 6 groups (n = 12/group) according to the system, each one with or without brushing: Reciproc Blue, VDW.Rotate, and Race EVO. Micro-computed tomography was performed before and after preparation. Brushing strokes caused no increase in canal volume, surface area, and structure model index independently of the system (p > 0.05), except for RaCe EVO in the full canal surface area (p < 0.05). Brushing did not increase the prepared areas (p > 0.05), except for Reciproc in the apical canal (p < 0.05). Reciproc with no brushing exhibited less pericervical dentin than with brushing (p < 0.05), while RaCe EVO with brushing resulted in less remaining dentin (p < 0.05). The brushing motion had no effects on the overall shaping performance of the 3 instruments tested. An exception was the increase in prepared surface area in the apical canal segment when the Reciproc instrument was used with brushing strokes.

Efficacy of Shock Wave-Enhanced Emission Photoacoustic Streaming (SWEEPS) in the Removal of Different Combinations of Sealers Used with Two Obturation Techniques: A Micro-CT Study.

This study sought to evaluate the efficacy of SWEEPS in the removal of epoxy-resin-based and calcium-silicate-containing endodontic sealer combined with single-cone and carrier-based obturation techniques through a micro-CT analysis. Seventy-six single-rooted extracted human teeth with single root canal were instrumented with Reciproc instruments. Specimens were randomly divided into four groups (n = 19) according to the root canal filling material and obturation technique: (1) AH Plus sealer + Reciproc gutta-percha, (2) TotalFill BC sealer + TotalFill BC Points, (3) AH Plus sealer + Guttafusion obturator, and (4) MTA Fillapex + Guttafusion obturator. All specimens were re-treated one week later using Reciproc instruments. Following re-treatment, root canals were additionally irrigated using the Auto SWEEPS modality. The differences in the root canal filling remnants were analyzed by micro-CT scanning of each tooth after root canal obturation, after re-treatment, and after additional SWEEPS treatment. Statistical analysis was performed using an analysis of variance (p < 0.05). The additional treatment with SWEEPS significantly reduced the volume of the root canal filling materials in all experimental groups compared to the removal of root canal filling using only reciprocating instruments (p < 0.05). However, the root canal filling was not removed completely from any of the samples. SWEEPS can be used to enhance the removal of both epoxy-resin-based and calcium-silicate-containing sealers, in combination with single-cone and carrier-based obturation techniques.