Radiopaque Solution Research Articles

Efficacy of sonic and ultrasonic activation on irrigant penetration in different tapered preparations: An in vitro study

ABSTRACT Background: The traditional syringe needle irrigation method would compromise on cleaning the intricacies of the complex root canal system. Current literature has focused on the benefits of various irrigant activation techniques. The present study aims to evaluate the irrigant penetration in extracted single-rooted teeth using various irrigant activation systems in different tapered preparations. Materials and Methods: One hundred and twenty-four single-rooted teeth were selected for the present study. They were standardized at the level of cementoenamel junction and shaped to 30 size using 4% and 6% taper rotary instruments under a standard irrigation regimen. Once the complete root canal preparations were done based on activation protocols, they were divided into four groups as Group 1: Four percent preparation sonic activation (n = 31), Group 2: Six percent preparation sonic activation (n = 31), Group 3: Four percent preparation ultrasonic activation (n = 31), and Group 4: Six percent preparation ultrasonic activation (n = 31). A radiopaque solution in conjunction with radiography was utilized to evaluate the penetration of irrigants into the canal. Radiographs were taken after dye injection to measure the length of irrigant penetration in each technique. Results were statistically analyzed using SPSS software. One-way ANOVA and Post hoc Tukey tests were performed. Results: The results of the study revealed that ultrasonic activation after 6% taper instrumentation was better followed by ultrasonic activation after 4% taper instrumentation (P < 0.05). The results revealed a statistically significant difference (P < 0.05) between the irrigation techniques. Conclusion: Ultrasonic irrigant activation proved to be a better and an effective technique for cleaning the root canal.

Impact of the spatial orientation of the patient's head, metal artifact reduction, and tube current on cone-beam computed tomography artifact expression adjacent to a dental implant: A laboratory study using a simulated surgical guide.

The aim of this study was to evaluate image artifacts in the vicinity of dental implants in cone-beam computed tomography (CBCT) scans obtained with different spatial orientations, tube current levels, and metal artifact reduction algorithm (MAR) conditions. One dental implant and 2 tubes filled with a radiopaque solution were placed in the posterior region of a mandible using a surgical guide to ensure parallel alignment. CBCT scans were acquired with the mandible in 2 spatial orientations in relation to the X-ray projection plane (standard and modified) at 3 tube current levels: 5, 8, and 11 mA. CBCT scans were repeated without the implant and were reconstructed with and without MAR. The mean voxel and noise values of each tube were obtained and compared using multi-way analysis of variance and the Tukey test (α=0.05). Mean voxel values were significantly higher and noise values were significantly lower in the modified orientation than in the standard orientation (P<0.05). MAR activation and tube current levels did not show significant differences in most cases of the modified spatial orientation and in the absence of the dental implant (P>0.05). Modifying the spatial orientation of the head increased brightness and reduced spatial orientation noise in adjacent regions of a dental implant, with no influence from the tube current level and MAR.

The Use of Headless Screws in the Setting of an Acute Posterior Calcaneal Avulsion Fracture in the Pediatric Population: A Case Report

Background: Sever’s is the most common cause of heel pain in the pediatric population and increases the risk of calcaneal apophyseal avulsion fractures. This is an uncommon fracture that faces problems with tenuous soft tissue coverage and high shear forces at the fracture site. Multiple fixation techniques have been employed in addressing this injury, with no one method standing out as superior. Case Presentation: We present a case of a 13-year-old male with a calcaneal apophyseal avulsion fracture in which cannulated headless compression screws were used for fixation. This was found to provide adequate compression across the fracture with minimal hardware prominence. This also allowed for the injection of radiopaque solution through the cannulated screw to rule out subtalar intraarticular penetration. We believe this represents a novel method of addressing these injuries. Conclusion: Cannulated headless compression screws are a suitable fixation technique for pediatric apophyseal avulsion fractures that provide the added benefit of assessment of intra-articular penetration of the subtalar joint by the injection of radiopaque solution through the cannulated screw.

An in vitro radiological evaluation of irrigant penetration in the root canals using three different irrigation systems: Waterpik WP-100 device, passive irrigation, and manual dynamic irrigation systems.

Background:Instrumentation and irrigation of the root canal facilitating effective debridement is considered the most important single factor in the prevention and treatment of endodontic diseases.Aim:The aim of the study was to evaluate the depth of penetration of the irrigant depending on the final activation using Waterpik device modified with NaviTip needle, passive irrigation, and manual dynamic activation using the radiopaque solution in conjunction with digital dental radiography.Materials and Methods:Ninety freshly extracted single-rooted mandibular premolars based on the inclusion and exclusion criteria were used for this study. Access cavity preparation was done for all the samples, and the working length of each sample was determined using a size 10-k file. The radiopaque solution (Urografin) was delivered into (Groups A, B, and C) prepared canal of samples at the rate of 1 ml in 30 s with up-and-down motion.Results:The test results showed that Waterpik WP-100 group showed significantly high infiltration index values as compared to passive irrigation and manual irrigation group at P < 0.002 and P = 0.007, respectively.Conclusion:Sonic irrigation using a Waterpik device modified with a NaviTip needle permits better infiltration of the irrigant.

IMPACT OF THE COMBINED EFFECT OF EXOMASS-RELATED AND MOTION ARTIFACTS IN CONE BEAM COMPUTED TOMOGRAPHY

BACKGROUNDExomass-related and motion artifacts are commonly observed in the everyday clinic and negatively affect cone beam computed tomography (CBCT) image quality. These 2 entities can be expected to occur in conjunction; however, they have only been assessed separately by the scientific community.OBJECTIVE(S)To assess quantitatively the combined effect of exomass-related and motion artifacts on voxel value parameters in CBCT.STUDY DESIGNA cylindrical phantom was manufactured containing 21 tubes filled with a radiopaque solution, allowing the inclusion of 3 titanium implants in the periphery to induce exomass-related artifacts. The phantom was mounted on a robot simulating 0.75-, 1.5-, and 3-mm movements (nodding/lateral rotation/tremor). CBCT images with/without exomass and with/without movements were acquired in duplicate in 3 units: Cranex 3Dx, Orthophos SL-3D, and X1 (with motion artefact correction). A cylindrical volume of interest was defined in each tube and voxel value means and standard deviations were assessed. For each CBCT volume, the 21 mean voxel values were averaged, providing the overall mean voxel value (MVV). The standard deviation (among the 21 values) was calculated, providing overall voxel value inhomogeneity (VVI). The standard deviations from each of the 21 volumes of interest were averaged, providing overall image noise. The effect of the diverse tested situations was inferred from a repeated-measures analysis of variance, followed by Sidak's test (α = .05).RESULTSOverall, images acquired with exomass showed significantly lower MVV and higher VVI and image noise (P ≤ .05). Motion artifacts aggravated exomass-related alterations. MVV and VVI were mostly affected by 3-mm nodding movements. Motion artifact correction eliminated the deleterious effect of movement.DISCUSSION/CONCLUSIONSCBCT voxel value parameters are altered by exomass-related artifacts, and this finding is aggravated in the presence of motion artifacts. Motion artifact correction effectively eliminated the deleterious effect of movement. Exomass-related and motion artifacts are commonly observed in the everyday clinic and negatively affect cone beam computed tomography (CBCT) image quality. These 2 entities can be expected to occur in conjunction; however, they have only been assessed separately by the scientific community. To assess quantitatively the combined effect of exomass-related and motion artifacts on voxel value parameters in CBCT. A cylindrical phantom was manufactured containing 21 tubes filled with a radiopaque solution, allowing the inclusion of 3 titanium implants in the periphery to induce exomass-related artifacts. The phantom was mounted on a robot simulating 0.75-, 1.5-, and 3-mm movements (nodding/lateral rotation/tremor). CBCT images with/without exomass and with/without movements were acquired in duplicate in 3 units: Cranex 3Dx, Orthophos SL-3D, and X1 (with motion artefact correction). A cylindrical volume of interest was defined in each tube and voxel value means and standard deviations were assessed. For each CBCT volume, the 21 mean voxel values were averaged, providing the overall mean voxel value (MVV). The standard deviation (among the 21 values) was calculated, providing overall voxel value inhomogeneity (VVI). The standard deviations from each of the 21 volumes of interest were averaged, providing overall image noise. The effect of the diverse tested situations was inferred from a repeated-measures analysis of variance, followed by Sidak's test (α = .05). Overall, images acquired with exomass showed significantly lower MVV and higher VVI and image noise (P ≤ .05). Motion artifacts aggravated exomass-related alterations. MVV and VVI were mostly affected by 3-mm nodding movements. Motion artifact correction eliminated the deleterious effect of movement. CBCT voxel value parameters are altered by exomass-related artifacts, and this finding is aggravated in the presence of motion artifacts. Motion artifact correction effectively eliminated the deleterious effect of movement.

INFLUENCE OF THE DISTANCE OF A METAL FROM THE FIELD OF VIEW PERIPHERY ON CONE-BEAM COMPUTED TOMOGRAPHY ARTIFACTS

<h3>BACKGROUND</h3> The presence of metal in the exomass (zone between the x-ray source and the image receptor) negatively affects image quality in cone beam computed tomography (CBCT), which cannot be effectively corrected by metal artifact reduction algorithms. However, considering that a metallic object can assume different positions in the exomass, the distance from the field of view (FOV) periphery could affect this condition. <h3>OBJECTIVE(S)</h3> The aim of this study was to evaluate the influence of the distance of metallic materials from the periphery of the FOV on the behavior of the CBCT artifacts. <h3>STUDY DESIGN</h3> An imaging phantom was custom made with 16 polypropylene tubes filled with a homogeneous radiopaque solution. CBCT scans were obtained by using a Picasso Trio unit adjusted to 90 kVp, 3 mA, and voxel size of 0.2 mm. The phantom was centered on a 5 × 5 cm FOV under protocols varying the composition (titanium or cobalt-chromium), quantity (0, 1, 2, or 3), and distance from the FOV periphery (2 cm, 3.5 cm, and 5.5 cm) of an object in the exomass. Means of voxel values were obtained from the 16 tubes of the phantom and the standard deviation was calculated as a way of measuring the variability values of each acquisition. Analysis of variance and Tukey's test compared separately the mean voxel and variability values between the different protocols (α = .05). <h3>RESULTS</h3> The mean voxel values were significantly lower (<i>P</i> < .05) for titanium at 5.5 cm and for 2 or 3 cobalt-chromium objects at 2 cm. In most conditions, the variability was significantly higher (<i>P</i> < .05) when the metallic object was at 2 cm. <h3>DISCUSSION/CONCLUSIONS</h3> The shortest distance of metallic materials from the FOV periphery had a greater impact on the CBCT artifacts.

Mapping the periapex anatomical pattern of teeth involved in sodium hypochlorite accidents: a cross-sectional quasi-experimental study.

To determine the anatomical reasons for sodium hypochlorite (NaOCl) accidents by testing whether this mishap is likely to occur in cases where the anatomical apex of the teeth fenestrates the overlying buccal cortical alveolar bone, allowing NaOCl to gain direct access to buccal soft tissues. Following a cross-sectional, nonrandomized design, 13 patients who suffered unintentional NaOCl accidents whilst undergoing root canal treatment were included. After remission of symptoms, the root canals were fully irrigated with an innocuous radiopaque solution (saline diluted Claritrast 300) and subsequently CBCT scanned to create a 3D-map of the periapex and tracking of the irrigant pathway throughout the periapical tissues. An extra group of five control patients, who underwent root canal treatment with no NaOCl accident, was also CBCT-scanned after irrigation with the tracking radiopaque solution. The anatomical relationship of the cortical bone and the root apex, as well as the distribution of irrigation solution in the periapical tissue, was associated with patients undergoing a NaOCl accident or not, using a Fisher's exact test. The frequency of teeth with apical cortical fenestration was significantly higher in the NaOCl accident-positive group, compared to the negative (P<0.001). All 13 accident-positive patients had an anatomical apex in direct contact with the buccal soft tissue via fenestration of the overlying cortical bone and direct contact of the foramen with the soft tissues. The radiopaque solution was distributed in the soft tissue in these cases. In contrast, accident-negative patients had no fenestration of the buccal cortical bone and the anatomical root apex was within the cancellous bone or within a bone-confined periapical lesion. The radiopaque solution was also found in the cancellous bone or the periapical lesion, but patients had no manifestations of a NaOCl accident. This quasi-experimental cross-sectional clinical study suggests that, in addition to the presence of the extruded NaOCl solution, a patent foramen that fenestrates the cortical bone merging into the mucosal tissue might constitute a risk for the clinical manifestation of a NaOCl accident. Preoperative 3D scans aid in anticipating when an accident is likely to occur.

Cadaveric Evaluation of Injectate Distribution for Two Maxillary Nerve Block Techniques in Cats.

Regional nerve blocks have been shown to decrease general anesthetic drug requirements and improve pain management in patients undergoing surgery. Regional nerve blocks are used routinely in patients undergoing oral surgery, such as dental extractions. There is little published information regarding the efficacy of feline maxillary and infraorbital nerve blocks. The goal of the study was to compare injectate distributions of the infraorbital foramen and percutaneous maxillary nerve block techniques in feline cadavers using a combined dye and radiopaque contrast media solution to simulate an injection. There was no significant difference in length of stained nerve between the two different techniques. It was not necessary to advance the needle into the infraorbital canal to achieve effective staining of the maxillary nerve. There was no significant difference in injectate distribution between two different injectate volumes, 0.2 and 0.4 ml, indicating that the smaller volume injected at the infraorbital foramen resulted in adequate nerve staining.

Influence of the exomass on the detection of simulated root fracture in cone-beam CT - an ex-vivo study.

To evaluate the influence of exomass-related metal artefacts on the detection of simulated vertical root fracture (VRF) in cone-beam computed tomography (CBCT). 20 teeth were endodontically instrumented and VRF was induced in half of them. All teeth were individually placed in an empty socket of a human mandible. Metallic materials were differently arranged in the exomass [zone outside of the field of view (FOV) but between the X-ray source and the receptor] and/or endomass (zone inside of the FOV), and CBCT scans were obtained. Four radiologists evaluated the presence of VRF using a 5-point scale. Sensitivity, specificity, and area under the receiver operating curve (AUC) were compared using ANOVA. Also, the tooth of interest was replaced with a tube filled with a radiopaque solution and all CBCT scans were repeated to analyse the data objectively. Mean grey and noise values were obtained from the tube and compared using ANOVA followed by Tukey's test (α = 0.05). Mean grey values were significantly lower and noise was significantly higher when metallic materials were present in the endomass or both the exomass and endomass. Sensitivity, specificity, and AUC were not influenced by the artefacts from the metallic materials irrespective of the arrangement condition. Exomass-related metal artefacts did not influence the diagnosis of simulated VRF in CBCT.

Objective assessment of the combined effect of exomass-related- and motion artefacts in cone beam CT.

To assess quantitatively the combined effect of exomass-related- and motion artefacts on voxel value parameters in cone beam CT (CBCT). A cylindrical phantom was manufactured, containing 21 tubes filled with a radiopaque solution, allowing the inclusion of three titanium implants in the periphery to induce exomass-related artefacts. The phantom was mounted on a robot simulating 0.75-, 1.5-, and 3 mm movements (nodding/lateral rotation/tremor). CBCT images with/without exomass and with/without movements were acquired in duplicate in three units: Cranex 3Dx, Orthophos SL-3D, and X1 (with motion-artefact correction). A cylindrical volume of interest was defined in each tube and voxel value mean and standard deviation were assessed. For each CBCT volume, the 21 mean voxel values were averaged providing the overall mean voxel value (MVV), and the standard deviation (among the 21 values) was calculated providing overall voxel value inhomogeneity (VVI). The standard deviation from each of the 21 volumes-of-interest were averaged, providing overall image noise (IN). The effect of the diverse tested situations was inferred from a repeated-measures analysis of variance, followed by Sidak's test (α = 0.05). Overall, images acquired with exomass showed significantly (p ≤ 0.05) lower MVV, and higher VVI and IN. Motion artefacts aggravated exomass-related alterations. MVV and VVI were mostly affected by 3 mm nodding movements. Motion-artefact correction eliminated the deleterious effect of movement. CBCT voxel-value parameters are altered by exomass-related artefacts, and this finding is aggravated in the presence of motion artefacts. Motion-artefact correction effectively eliminated the deleterious impact of movement.

Are metal artefact reduction algorithms effective to correct cone beam CT artefacts arising from the exomass?

The aim of this study was to evaluate the effectiveness of metal artefact reduction (MAR) in cone beam CT (CBCT) artefacts arising from metallic objects in the exomass. A radiographic phantom composed of 16 polypropylene tubes filled with a homogeneous radiopaque solution was created. CBCT scans were obtained with two units: Picasso Trio (Vatech, South Korea) and ProMax (Planmeca, Finland). The phantom was centred in a 5 × 5 cm field-of-view (FOV) with titanium and CoCr inserts in the exomass. All scans were repeated after enabling MAR. Mean voxel values were obtained from the 16 tubes and standard deviation was calculated as a way of measuring voxel value variability. Mean values and voxel value variability were compared individually in the presence and absence of MAR by means of analysis of variance, followed by Tukey's test (α = 0.05). In the Picasso Trio, MAR significantly decreased mean voxel values (p ≤ 0.05) and increased voxel value variability (p > 0.05) in the presence of titanium. When CoCr was present, no statistical difference (p > 0.05) was observed. In the ProMax, MAR increased significantly mean voxel values (p ≤ 0.05) in the presence of titanium, and presented no significant difference (p > 0.05) for CoCr. Voxel value variability did not differ significantly (p > 0.05) for both materials. In conclusion, MAR was not effective to correct CBCT artefacts arising from metallic objects in the exomass in the two CBCT units used.

Radiological Evaluation of Penetration of the Irrigant according to Three Endodontic Irrigation Techniques.

Introduction. This experimental study is to compare radiographs based on the penetration depth of the irrigant following three final irrigation techniques. Material and Method. A sample of sixty teeth with single roots were prepared with stainless steel K files followed by mechanized Ni-Ti files iRace® under irrigation with 2.5% sodium hypochlorite. Radiopaque solution was utilized to measure the penetration depth of the irrigant. Three irrigation techniques were performed during this study: (i) passive irrigation, (ii) manually activated irrigation, and (iii) passive irrigation with an endodontic needle CANAL CLEAN®. Radiographs were performed to measure the length of irrigant penetration in each technique. Results. In comparison, passive irrigation with a conventional syringe showed infiltration of the irrigant by an average of 0.682 ± 0.105, whereas the manually activated irrigation technique indicated an average of 0.876 ± 0.066 infiltration. Irrigation with an endodontic syringe showed an average infiltration of 0.910 ± 0.043. The results revealed highly significant difference between the three irrigation techniques (α = 5%). Conclusion. Adding manual activation to the irrigant improved the result by 20%. This study indicates that passive irrigation with an endodontic needle has proved to be the most effective irrigation technique of the canal system.

Effect of maintaining apical patency and passive ultrasonic irrigation on irrigant penetration into the apical third of root canals: An in vivo study

Introduction: The aim of this study was to determine whether the use of a patency file and passive ultrasonic irrigation (PUI) is related to the presence of a radiopaque irrigating solution in the apical third of human root canals in vivo. Materials and Methods: 20 human root canals were randomly divided into 4 groups. 1: Conventional needle irrigation without apical patency, 2: PUI without apical patency, 3: Conventional needle irrigation with apical patency, 4: PUI with apical patency. Apical patency was maintained with a no. 10 K-file 1mm beyond the working length. PUI was done using an endosonic file attached to the ultrasonic unit. The canals were shaped with the Pro Taper system. Irrigation was performed with solution prepared with a radiopaque contrast medium and sodium hypochlorite 5.25%. Digital images were taken and a calibrated reader determined the presence or absence of the irrigating solution in the apical third. Results: Significantly more canals with irrigant in the apical third were found after PUI and after maintain apical patency. Conclusion: PUI and maintaining apical patency improves irrigant penetration.

Optimization and characterization of injectable chitosan-iodixanol-based hydrogels for the embolization of blood vessels.

Chitosan-thermosensitive hydrogels present interesting features for the embolization of blood vessels, but need to be better characterized and optimized. Chitosan polymer (degree of deacetylation (DDA) of 94%) was purified and combined with Visipaque (VIS), a nonionic isotonic contrast agent composed of iodixanol. A beta-glycerolphosphate (βGP) solution was then added to induce gelation at body temperature. The gelation process was monitored by rheometry, measuring the evolution of the sample storage (G') and loss (G″) moduli as a function of VIS and βGP concentration. Adding VIS significantly slowed down gelation kinetics, but a 12% and higher βGP concentration provided a radiopaque solution, which at 37°C, gels immediately. A custom-made in vitro embolization bench test was developed to assess the gel's occlusive properties, and its injectability through a small diameter catheter was verified. Results show that the short-term occlusive properties of the gel were insufficient when using a βGP concentration of 12% w/v (about 0.4M), but that increasing the βGP to 20% (0.6M) allowed an acceleration of the gelation and the immediate blocking of flow above physiological pressure. The contrast agent was rapidly released in solution, such that it would not interfere with future follow-up imaging. In accordance with the literature data, the cytotoxicity of gel extracts increased with βGP concentration and to a lesser extent with VIS concentration. Preliminary in vivo testing showed easy injection by catheter and good visibility under fluoroscopy. These results suggest that radiopaque CH/βGP20%/VIS hydrogels present significant potential as embolizing agents for blood vessels and aneurysms. © 2015 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 104B: 1551-1562, 2016.

Arterial vascularization of the flexor digitorum superficialis synovial flap. An anatomical study

Among the various techniques proposed to protect the median nerve from scarring and to provide it with a vascular supply, the synovial flap represents a simple and effective method. The flap is taken from the flexor tendons sheath and results in a thin and richly vascularized tissue that will act as a barrier to scarring and provide neovascularization to improve nerve regeneration and gliding. The aim of this study was to evaluate the arterial vascularization of this flap to assess its reliability. An anatomic study was carried out on 24 fresh upper limbs infused with colored and radiopaque solutions before or after flap elevation. Anatomical findings showed the synovial flap to be supplied by a consistent vascular pedicle arising from the ulnar artery 2 to 5 centimeters proximal to the pisiform bone and running between the flexor tendons of the ring and little fingers. The synovial flap is known to be a simple and effective method for protecting the median nerve. The present study shows that its consistent vascularization makes it a reliable technique. We believe this procedure is relevant for the treatment of recurring carpal tunnel syndrome.

TECHNIQUE FOR ULTRASOUND‐GUIDED INTRAARTICULAR CERVICAL ARTICULAR PROCESS INJECTION IN THE DOG

Ultrasound-guided intraarticular injection of cervical articular process joints is a well-established procedure in both humans and horses for neck pain resulting from osteoarthritis, but the technique has not been described in dogs. Aims of this study were to describe the ultrasonographic anatomy and landmarks for cervical articular process joint injections in the dog, develop a technique for articular process joint injections using these landmarks, and determine the accuracy of injections and factors that may influence it. Eleven canine cadavers were used and bilateral joint spaces from C2-3 to C7-T1 were injected under ultrasound guidance with a blue radiopaque solution. A computed tomographic scan was acquired following each injection, and an injection score was assigned and compared with other patient-specific factors. Of the 132 injections performed, 110 (83.3%) were intraarticular, 20 (15.1%) were periarticular within 5 mm, and 2 (1.5%) were periarticular beyond 5 mm from the joint. There was no significant difference in mean scores between dogs. Only C2-3 had a significantly lower mean score than any other joint. There was no significant correlation between injection score and any other factors measured. The transverse processes of the cervical vertebrae served as excellent ultrasonographic landmarks for identifying the cervical articular process joints in dogs regardless of the size of the dog or location along the vertebrae. Accuracy of ultrasound-guided intraarticular process joint injection was 83% in dogs and similar to published techniques in horses. Further studies are needed to examine the safety and efficacy of this procedure in live animals.

Fluoroscopic evaluation of gastrointestinal transit time in African Grey parrots

Contrast studies are commonly performed to evaluate the gastrointestinal tract. With ever increasing knowledge of Proventricular Dilation Disease (PDD) in psittacines, and its association with avian bornavirus, radiographic assessment of...

Fluoroscopic evaluation of gastrointestinal transit time in African Grey parrots

Contrast studies are commonly performed to evaluate the gastrointestinal tract. With ever increasing knowledge of Proventricular Dilation Disease (PDD) in psittacines, and its association with avian bornavirus, radiographic assessment of...

In Vivo Efficacy of Three Different Endodontic Irrigation Systems for Irrigant Delivery to Working Length of Mesial Canals of Mandibular Molars

IntroductionMany in vitro studies have debated over the ability of different irrigant delivery and/or agitation systems to reach the apical third of curved root canals; however, little is known about irrigant penetration in vivo. Therefore, the purpose of this study was to compare the efficacy of the conventional endodontic irrigation needle, passive ultrasonic irrigation (PUI), and a negative pressure system for irrigant delivery to working length (WL) of mesial canals of mandibular molars. MethodsThirty mesial canals of 30 vital mandibular first or second molars were randomly assigned into 3 groups (n = 10): (1) Monoject syringe with 27-gauge needle; (2) PUI with IrriSafe tip; and (3) EndoVac system. All canals were treated following the same preparation protocol to size 35/0.04 by using 5.25% NaOCl as irrigant during preparation procedure. Before obturation, canals were irrigated with 1 mL of a radiopaque solution by using the assigned irrigation system, and a digital radiograph was taken by using a parallel technique. With the aid of image editing software the distance between WL and maximum irrigant penetration was measured. ResultsMean distances for Monoject, PUI, and EndoVac groups were 1.51 mm, 0.21 mm, and 0.42 mm, respectively. Analysis of variance test showed statistically significant differences between groups (P < .001). Tukey honestly significant difference test showed statistically significant differences between the Monoject group and the other 2 groups (P < .001) but no significant differences between PUI and EndoVac groups (P = .06). ConclusionsPUI and EndoVac are more effective than the conventional endodontic needle in delivering irrigant to WL of root canals.

Effect of oesophagitis on proximal extent of gastro‐oesophageal reflux

Proximal oesophageal acid reflux is increased in gastro-oesophageal reflux disease (GORD) patients with oesophageal and extra-oesophageal symptoms, the latter particularly in presence of oesophagitis. This study was aimed to assess the proximal extent of reflux, both acid and weakly acidic, in GORD patients with and without oesophagitis and to characterize, using an animal model of GORD, the relationship between acute oesophagitis and proximal extent of reflux. Proximal extent of reflux was evaluated during 24-h pH-impedance monitoring in 17 oesophagitis, 27 non-erosive reflux disease (NERD) patients and 10 asymptomatic controls. In five adult cats, reflux events were simulated by intra-oesophageal retrograde injection of a radiopaque solution. Proximal extent of simulated reflux was fluoroscopically assessed before and after inducing acute oesophagitis. The percentage of proximal reflux was 11% in controls, 22% in NERD and 38% in oesophagitis patients (P < 0.05 vs NERD). Weakly acidic reflux showed higher proximal extent in oesophagitis than in NERD patients but it was less proximally propagated than acid reflux. In cats, proximal reflux was significantly increased during acute oesophagitis. Oesophagitis patients show higher proximal extent of reflux, acid and weakly acidic, when compared with NERD patients and controls. In the experimental model, acute oesophagitis favours proximal migration of simulated reflux.