Lateral Canal Research Articles

Correlation between cognitive tests with scales, vestibular exam and questionnaires for dizziness in the elderly

AbstractBackgroundThe vestibular system interacts with various cognitive functions, including spatial navigation processes, spatial perception, body representation, mental images, attention, memory, risk perception and social cognition. Studies inform that cognitive impairment is an important risk factor for changes in motor performance and body balance.MethodCross‐sectional, observational and analytical study. The sample consisted of 38 elderly people with vestibular dysfunction confirmed by cervical and ocular VEMP exams and/or Video Head Impulse Test (v‐HIT). The procedures of this research were approved by the Ethics Committee of the University under the number CAAE 49714221.0.0000.5149. All participants signed the Informed Consent Form (FICF). Cognitive tests were applied in a room with the patient seated. Paper and pencil were used and all cognitive tests, scales and vestibular exams were performed by the same trained researcher. Analysis using the SPSS program ‐ version 22.0. The distribution of variables was verified using the Kolmogorov‐Smirnov test. Correlation analysis was performed using the Pearson test. We adopted a significance level of 5% (p<0.05).ResultA positive correlation was found between the MMSE with the gain of the left semicircular canal and negative with the asymmetry of the lateral canals. The Frontal Assessment Battery was negatively correlated with the VAS and positively correlated with the left semicircular canal. The Pfeffer questionnaire showed a positive correlation with the VAS, DHI and its functional and emotional subscales, in addition to a negative correlation with the Berg balance scale. The geriatric depression scale correlated negatively with the VAS and the Berg balance scale and positively correlated with the total DHI and its functional and emotional subscales.ConclusionIn this study, cognitive aspects, depressive symptoms and functionality were correlated with decreased gain of the left semicircular canal, greater asymmetry of the lateral canals, higher scores on the visual analogue scale, greater impact of dizziness on quality of life and greater risk of falls.

Vestibular mapping in Ramsay-Hunt syndrome and idiopathic sudden sensorineural hearing loss.

To observe vestibular impairment patterns in patients with Ramsay Hunt syndrome with dizziness (RHS_D) and sudden sensorineural hearing loss with dizziness (SSNHL_D) using hierarchical cluster analysis (HCA) to interpret results with possible mechanisms. The data of 30 RHS_D and 81 SSNHL_D patients from January 2017 to August 2022 in a single tertiary referral center were retrospectively analyzed. Video head impulse test (vHIT) and vestibular evoked myogenic potential (VEMP) were used for vestibular analysis of peripheral vestibular organs, and the results of vHIT and VEMP were analyzed. HCA was used to analyze vestibular impairment patterns. In RHS_D patients, the lateral semicircular canal (LSCC) was the most impaired semicircular canal (SCC), followed by the anterior semicircular canal (ASCC) and the posterior semicircular canal (PSCC), and the utricle was more impaired than the saccule. In SSNHL_D patients, the PSCC was the most impaired SCC, followed by the LSCC and the ASCC, and the utricle was more impaired than the saccule. In HCA of RHS_D patients, the ASCC and utricle were initially clustered, followed by the LSCC, PSCC and saccule in order. In the HCA of SSNHL_D patients, the PSCC was solely merged and independently clustered. There were different patterns of vestibular impairments between RHS_D and SSNHL_D patients. The vestibular analysis and HCA results of SSNHL_D showed tendency of skip lesion, which could be explained by vascular pathophysiology.

Menière's Syndrome Associated With Fibrous Dysplasia of the Temporal Bone.

Menière's Syndrome Associated With Fibrous Dysplasia of the Temporal Bone.

Abnormal Nystagmus Induced by Peripheral Vestibular Disorders

Electrophysiological measurement of the eye rotation axis using stimulation of a single semicircular canal nerve showed that the eye rotated around the axis perpendicular to the plane of the stimulated semicircular canal. Therefore, the affected semicircular canal can be identified by analyzing the eye rotation axis in cases of abnormal nystagmus. When the main component of the abnormal nystagmus is horizontal, the origin of the nystagmus is the lateral semicircular canal. When the main component of the abnormal nystagmus is torsional, the origin of the nystagmus is the anterior and/or posterior semicircular canal. The eye rotation axis in cases of excitatory nystagmus is quite the same as that in cases of inhibitory nystagmus, although the direction of eye rotation is opposite between cases of excitatory and inhibitory nystagmus. Vestibular neuritis mostly involves the superior vestibular nerve. The superior vestibular nerve transmits sensory information transmitted by from the vestibular hair cells located in the anterior and lateral semicircular canals. Therefore, patients with vestibular neuritis exhibit nystagmus with both horizontal and torsional components caused by inhibition of both the anterior and lateral semicircular canals. In patients with Ménière's disease, during a vertigo attack, excitatory nystagmus of anterior and/or posterior and/or lateral semicircular canal origin can be seen. Because the involving ratio of each contributing ratios of the three semicircular canals to nystagmus can vary, the ratio of the torsional component of the nystagmus to the horizontal component also varies. While nystagmus is purely horizontal in some cases, it is purely torsional in others. In the posterior canal type of BPPV, during the Dix-Hallpike maneuver, transient torsional nystagmus with the torsional component directed toward the affected side can be seen. In the lateral canal type of BPPV (canalolithiasis), geotropic positional nystagmus can be seen when the patient is supine. In the lateral canal type of BPPV (cupulolithiasis), apogeotropic positional nystagmus can be seen when the patient is supine.

Root and canal morphology of third molar teeth

Restorative and prosthetic considerations usually necessitates endodontic treatment of third molars in order to retain them as a functional component of the dental arch. However, the anatomy of third molars has been described as unpredictable. To date, there has been little published work on root and canal morphology of third molars, with an adequate sample size. The aim of this study was to investigate root and canal morphology of third molars. Maxillary and mandibular third molars were gathered from dental surgeries within north Jordan. Following access cavity preparation, pulp tissue was removed and root canals stained. Teeth were subject to examination after rendering them clear by immersion in methyl salicylate, and the following features evaluated: (1) number of roots; (2) number and type of root canals; (3) number and position of lateral canals; and (4) presence of inter-canal communications. Out of the examined 592 maxillary third molars, 69.9% had three roots, 10.81% had one, 9.79% had two, 9.12% had four, and 0.34% had five roots. Most had three (52.36%) and four canals (28.2%) with less frequency of two (11.48%), one (5.91%) and five canals (2.03%). Of the 639 mandibular third molars, 89.76% had two roots, 7.35% had three, 2.5% had one, and 0.47% had four roots. Most had three (55.71%) and two canals (29.42%) with less frequency of four (13.61%), one (1.09%) and five canals (0.15%). The majority of maxillary third molars had 3 roots, while the majority of mandibular third molars had two. Overall, nearly half of the maxillary and mandibular third molars had three canals. New canal configurations, not previously described in the literature nor included in Vertucci’s classifications, were identified in both maxillary and mandibular third molars.

Comparative evaluation of post-operative pain & analgesic intake after root canal treatment using three bioceramic sealers- An In-vivo study

To evaluate the occurrence and intensity of post-operative pain & number of analgesic tablets intake after single visit endodontic treatment using three different Bioceramic sealers.45 single rooted teeth diagnosed with asymptomatic irreversible pulpits requiring endodontic treatment were randomly assigned to three groups (n=15) according to sealer used during obturation. To avoid bias in post-operative pain perception, each sealer is evaluated in three different single rooted teeth of the same patient. The different groups are Group 1-MTA-Fillapex, Group –II Ceraseal RCS, Group-III BioRoot RCS. Single visit Endodontic treatment was performed and teeth were obturated using cold lateral compaction and different root canal sealers with no radiographic material extrusion beyond the apex. Severity of post obturation pain was assessed by Visual Analog Scale (VAS) with score ranging from 0 to 10 at 6hrs, 12hrs, 24hrs and 48hrs intervals. The need for analgesic (Tab. Aceclofenac 100 mg) intake was also recorded. Differences in incidence of postoperative pain were analyzed using the Kruskal Wallis test followed by Mann Whitneys Post Hoc to compare the mean VAS score & number of analgesics taken between three groups at different time intervals (p<0.05).MTA Fillapex shows statistically significant difference in mean VAS score (more pain) at 6hrs, 12hrs (p value < 0.001) & at 24hrs (p<0.005) than Ceraseal RCS and BioRoot RCS. There is statistically significant difference in the no. of analgesic intake for MTA Fillapex i.e., more tablets taken by the patient to relive pain (p<0.001) as compared to Ceraseal RCS and BioRoot RCS. The decrease in pain was statistically significant for each time intervals from 6hrs to 48hrs for all the three groups.The teeth of the patients where MTA Fillapex sealer was used as a sealer in the obturation showed significantly more pain at 6hrs & 12hrs and needed to take more analgesics than teeth obturated with other two sealers. This probably could be due to leaching out of resin constituents from MTA Fillapex.

Treating benign paroxysmal positional vertigo of the lateral semicircular canal with a shortened forced position.

Benign paroxysmal positional vertigo (BPPV) is the peripheral vestibular disorder that is most frequently encountered in routine neuro-otological practice. Among the three semicircular canals, the lateral semicircular canal (LSC) is the second most frequently interested in the pathological process. In most cases, LSC BPPV is attributable to a canalithiasis or cupulolithiasis mechanism. The clinical picture of LSC BPPV is that of positional nystagmus and vertigo evoked by turning the head from the supine to the side lateral position. With such a movement, a horizontal positional (and often also paroxysmal) direction-changing nystagmus is generated. Depending on whether the pathogenetic mechanism is that of canalithiasis or cupulolithiasis and depending on where the dense particles are located, LSC BPPV direction-changing positional nystagmus is geotropic or apogeotropic on both lateral sides. Due to its mechanical nature, BPPV is effectively treated by means of physical therapy. In the case of a LSC BPPV, one of the most effective therapies is the forced prolonged position (FPP), in which the patient is invited to lie for 12 h on the lateral side on which vertigo and nystagmus are less intense, to move the canaliths out from the canal (or to shift them inside of the canal from one tract to another) exploiting the force of gravity. Despite its efficacy, FPP is not always well tolerated by every patient, and it cannot be done during the diagnostic session because of its duration. The present study aimed to verify the efficacy of a different forced position, shortened forced position (SFP), with respect to the original FPP. SFP treatment would allow patients to more easily bear the forced position and physicians to control the outcome almost immediately, possibly enabling them to dismiss patients without vertigo. After 1 h of lying on the side where vertigo and nystagmus are the less intense, 38 out of 53 (71.7%) patients treated with SFP were either healed or improved. Although the outcomes are not as satisfying as those of the original FPP, SFP should be considered as a therapeutic prospect, especially by those physicians who work in collaboration with emergency departments or otherwise encounter acute patients to cure them of vertigo as soon as possible.

An inter-observer assessment of mastoid pneumatization and degree classification using sigmoid sinus: comparing two levels of temporal bone computed tomograms

BackgroundThe degree of mastoid pneumatization of the temporal bone (TB) has been implicated in the pathogenesis of TB diseases and surgical implications, and planning of a few otologic surgeries. However, there is lack of consensus in the classification of the degree of pneumatization. This study aimed to suggest a simple, quick, and less-burden classification system for assessing and rating the degree of pneumatization by comparing two levels of TB computed tomographs (CTs) using the SS as a reference in an inter-observer assessment among otologists.MethodsThis was a randomized pilot survey among otologists. A questionnaire consisting of different axial CTs of TB taken at two levels: the level of malleoincudal junction (MIJ) and the level of lateral semicircular canal (LSCC), with different pneumatization patterns, was used to assess participants' impressions of the degree of pneumatization. The terms “hypo-,” “moderate,” “good,” and “hyper-” pneumatization were listed as options to rate their impressions on the degree of mastoid pneumatization of the TB images using the SS as a reference structure. Likert scale was used to assess their level of agreement or disagreement with using SS as a reference in evaluating mastoid pneumatization.ResultsParticipants who correctly rated images taken at the level of LSCC according to their respective degree of pneumatization were significantly higher (p < 0.05) regardless of their year of experience compared to those that correctly rated corresponding images taken at the level of MIJ. A 76% positivity in their level of agreement with the use of sigmoid sinus in evaluating mastoid pneumatization was observed on the Likert-scale chart.ConclusionFindings from this study suggest that evaluating air cells around the SS at the level of LSCC on CTs could be easier in assessing and classifying the degree of mastoid pneumatization.

What is the most important factor to preserve hearing in lateral semicircular canal fistula surgeries, fistula size or bony structure?

Cholesteatoma on lateral semicircular canal (LSCC) fistula > 2mm in size is likely to be unmanipulated due to the risk of sensorineural hearing loss. However, the matrix can be successfully removed without hearing loss when it is > 2mm. The purpose of the study was to evaluate surgical experience over the past 10years and to suggest the important factor for the hearing preservation in LSCC fistula surgeries. According to the fistula size and symptoms, 63 patients with LSCC fistula were grouped as follows: Type I (fistula < 2mm), Type II (≥ 2mm and < 4mm without vertigo), Type III (≥ 2mm and < 4mm with vertigo), Type IV (≥ 4mm), and Type V (any size fistula but with deafness at the initial visit). The cholesteatoma matrix was meticulously manipulated and removed by experienced surgeons. Only two patients completely lost their hearing after surgery (4.5%). However, the loss was inevitable because their cholesteatomas were highly invasive and there was also facial nerve canal involvement; thus, the bony structure of the LSCC was already destroyed by the cholesteatoma. Unlike these two Type IV patients, Type I-III patients, and those with a fistula size < 4mm, did not lose their sensorineural hearing. If the structure of the LSCC was maintained, hearing loss did not occur even if the fistula size ≥ 4mm. The preservation of the labyrinthine structure is more important than the defect size of the LSCC fistula. If the structure is intact, cholesteatoma matrices lying on the defect can be safely removed, even though the size of bony defect is large.

Demystifying C shaped canals

Introduction: Knowledge of root canal anatomy is essential in order to achieve a successful root canal treatment. C shaped canal anatomy is most commonly seen in mandibular second molars and to some extent mandibular premolars. Such canals are difficult to negotiate, debride/disinfect and obturate due to its high incidence of fins, webs, lateral canals and anastomoses. Inability to identify and debride such canal anatomy may lead to endodontic failure.Case Report: These case series highlights on two different c shaped canals with two different obturation techniques.Conclusion: Complexity of C shaped canal morphology can be managed successfully with proper irrigation and obturation techniques.

Evaluation of root canal morphology of mandibular central and lateral incisor in Mosul city by using CBCT

Background: Lower incisor endodontic treatment failures are primarily due to missing canals, notably the lingual canal. Aim: The incisors' root architecture and the number of canals of the mandibular would be evaluated using computed tomography using a cone beam (CBCT). Methods: 220 patients with age (18-75) years who visited Al Noor Dental Center in Mosul over the course of two years had their 780 central and lateral incisors of the jaw evaluated using 3D CBCT images. The classification of the Vertucci system was applied to determine how the root canal was shaped. Results: A comparison between the incisors of lateral and central canal shape using the Vertucci method, the number of central incisors with only one root was higher than the lateral incisors with the roots of the same number. Where it was found that the central incisors of the first type are 377 teeth, while the number of incisors Lateral 358, the number of incisors in the second type was 5 teeth, and the lateral 3 teeth. Conclusions: The root morphology of the sexes differs significantly. Various morphological alterations should be anticipated by the dental professional when undertaking endodontic treatment. To ascertain the morphological traits of the conductor's anterior tooth roots, additional research is required.

Rare Coding Variants in Patients with Non-Syndromic Vestibular Dysfunction.

Vertigo due to vestibular dysfunction is rare in children. The elucidation of its etiology will improve clinical management and the quality of life of patients. Genes for vestibular dysfunction were previously identified in patients with both hearing loss and vertigo. This study aimed to identify rare, coding variants in children with peripheral vertigo but no hearing loss, and in patients with potentially overlapping phenotypes, namely, Meniere's disease or idiopathic scoliosis. Rare variants were selected from the exome sequence data of 5 American children with vertigo, 226 Spanish patients with Meniere's disease, and 38 European-American probands with scoliosis. In children with vertigo, 17 variants were found in 15 genes involved in migraine, musculoskeletal phenotypes, and vestibular development. Three genes, OTOP1, HMX3, and LAMA2, have knockout mouse models for vestibular dysfunction. Moreover, HMX3 and LAMA2 were expressed in human vestibular tissues. Rare variants within ECM1, OTOP1, and OTOP2 were each identified in three adult patients with Meniere's disease. Additionally, an OTOP1 variant was identified in 11 adolescents with lateral semicircular canal asymmetry, 10 of whom have scoliosis. We hypothesize that peripheral vestibular dysfunction in children may be due to multiple rare variants within genes that are involved in the inner ear structure, migraine, and musculoskeletal disease.

Preceding Balance Disorders Affect Vestibular Function in Persistent Postural-Perceptual Dizziness.

Persistent postural-perceptual dizziness (PPPD) is induced by preceding conditions that cause balance disorders. To investigate the association between vestibular function and preceding balance disorders in PPPD patients, a retrospective chart review was performed. Vestibular function in 55 PPPD patients was measured using the caloric test, cervical vestibular evoked myogenic potential testing to air-conducted sound (ACS cVEMP), ocular vestibular evoked myogenic potential testing to bone-conducted vibration (BCV oVEMP), and video head impulse testing (vHIT). Patients were classified according to the type of preceding balance disorder. The age-stratified Cochran-Mantel-Haenszel (CMH) test and the exact test for the common odds ratio were conducted to evaluate the association between preceding n ≥ 4 balance disorders and present peripheral vestibular dysfunction. PPPD patients with preceding vestibular neuritis presented a significant positive association with abnormal caloric responses (p = 0.013), while those with preceding benign paroxysmal positional vertigo (BPPV) had significantly lower rates of abnormal BCV oVEMP (p = 0.003). Furthermore, patients with preceding vestibular neuritis showed lateral semicircular canal dysfunction, while those with preceding BPPV presented normal utricular functions. These results present the influence of preceding balance disorders on the vestibular function in PPPD.

Outcomes of canal wall down mastoidectomy in cholesteatoma: a 5-year experience

BackgroundCholesteatoma is an atticoantral disease that potentially causes life-threatening complications. Therefore, canal wall down mastoidectomy is a well-established technique to eradicate the disease, especially in extensive cholesteatoma.AimTo evaluate the status of dry ear and hearing outcome post-retrograde canal wall down mastoidectomy.MethodsA retrospective study of patients with cholesteatoma who underwent modified radical mastoidectomy (MRM), a form of canal wall down mastoidectomy between January 2014 and December 2018.ResultsFifty-seven patients were included with a mean age of 40 years. The majority of cases were adults, 86%, and 14% were children. Most of them complained of ear discharge (73.7%), followed by hearing loss (31.6%). Intraoperatively, cholesteatoma was primarily found in cases involving mastoid air cells, antrum, attic, and mesotympanum (47.4%). The presence of granulation tissue with cholesteatoma was noted in 57.9% of cases. Furthermore, 73.7 % of ossicular chain erosion cases involved erosion of all ossicles (47.6 %). In 26.3 % of cases, tegmen erosion was identified. Facial canal dehiscence accounted for 15.8% of MRM cases, sclerotic mastoid was noted for 10.5%, and lateral semicircular canal dehiscence involved 5.3%. Up to 3 months of follow-up post-MRM showed 70.2% had a dry ear. After 6 months, there were 15.8% complaints of ear discharge in the subsequent follow-up. In this study, 33 out of 57 patients underwent a postoperative hearing evaluation, and 21.2 % of patients showed an improvement in the air-bone gap.ConclusionCanal wall down mastoidectomy is a treatment of choice in extensive cholesteatoma to achieve a dry and safe ear with maintaining functional hearing outcomes.

Assessment of the distribution and volume of air chambers around the inner auditory canal on high-resolution computed tomography scans of the temporal bone.

Assessment of the distribution and volume of air chambers around the inner auditory canal on high-resolution computed tomography scans of the temporal bone.

IMPACT OF THE PASSIVE/ACTIVE ULTRASONIC ACTIVATION ON THE ENDODONTIC IRRIGANTS EFFECTIVENESS - A REVIEW

Introduction: various irrigation devices and chemical solutions are being developed and improved nowadays for better penetration deep into the complex root canal system. Activation of irrigating solutions enhances the solution effectiveness. Evidence in the literature suggests that ultrasonic irrigation is much more effective in this respect than syringe irrigation alone. Passive ultrasonic irrigation (PUI) and/or ultrasonically activated irrigation (UAI): nowadays, the two terms, PUI and UAI, are interchangeable in the literature and represent the same technique. Literature data have shown that combining ultrasonically activated NaOCl with EDTA results in significantly greater removal of the smear layer. Conclusion: the use of ultrasonic activation of the irrigating solution after root canal preparation significantly improves the removal of debris from hard-to-reach areas such as isthmuses, lateral canals and the apical delta.

Hybrid surgery of percutaneous transforaminal endoscopic surgery (PTES) combined with OLIF and anterolateral screws rod fixation for treatment of multi-level lumbar degenerative diseases with intervertebral instability

BackgroundOblique lumbar interbody fusion (OLIF) has been used to treat lumbar intervertebral instability, which has some advantages including less trauma, less blood loss, faster recovery and bigger cage. However, it usually needs posterior screws fixation for biomechanical stability, and possible direct decompression for relieving neurologic symptoms. In this study, OLIF and anterolateral screws rod fixation through mini-incision were combined with percutaneous transforaminal endoscopic surgery (PTES) for the treatment of multi-level lumbar degenerative diseases (LDDs) with intervertebral instability. The purpose of study is to evaluate the feasibility, efficacy and safety of this hybrid surgery.MethodsFrom July 2017 to May 2018, 38 cases of multi-level LDDs of disc herniation, foramen stenosis, lateral recess stenosis or central canal stenosis with intervertebral instability and neurologic symptoms undergoing one-stage PTES combined with OLIF and anterolateral screws rod fixation through mini-incision were recruited in this retrospective study. The culprit segment was predicted according to the position of patient’s leg pain and PTES under local anesthesia was performed for the culprit segment in the prone position to enlarge the foramen, remove the flavum ligamentum and herniated disc for the lateral recess decompression and expose bilateral traversing nerve roots for the central spinal canal decompression through an unilateral incision. During the operation, communicate with the patients to confirm the efficacy using VAS. And then mini-incision OLIF using allograft, autograft bone harvested in PTES and anterolateral screws rod fixation were performed in the right lateral decubitus position under general anesthesia. Back and leg pain were preoperatively and postoperatively evaluated using VAS. And the clinical outcomes were evaluated with ODI at the 2-year follow-up. The fusion status was assessed according to Bridwell’s fusion grades.ResultsThere were 27 cases of 2-level, 9 cases of 3-level and 2 cases of 4-level LDDs with single-level instability on the X-ray, CT and MRI. Five cases of L3/4 instability and 33 cases of L4/5 instability were included. PTES was performed for 1 segment of 31 cases (25 cases of instability segment, 6 cases of no instability segment) and 2 segments including instability segment of 7 cases. Then, all instability segments were treated using mini-incision OLIF and anterolateral screws rod fixation. The average operation duration was 48.9 ± 7.3 min per level for PTES and 69.2 ± 11.6 min for OLIF and anterolateral screws rod fixation. The mean frequency of intraoperative fluoroscopy was 6 (5–9) times per level for PTES and 7 (5–10) times for OLIF. There was a mean blood loss of 30 (15–60) ml, and the incision length was 8.1 ± 1.1 mm for PTES and 40.0 ± 3.2 mm for OLIF. The mean hospital stay was 4 (3–6) days. The average follow-up duration was 31.1 ± 4.0 months. For the clinical evaluation, the VAS pain index and the ODI showed excellent outcomes. Fusion grades based on the Bridwell grading system at 2-year follow-up were grade I in 29 segments (76.3%) and grade II in 9 segments (23.7%). One patient encountered nerve root sleeves rupture during PTES and did not confront cerebrospinal fluid leakage or other abnormal clinical symptoms. There were two cases of hip flexion pain and weakness, which was relieved during 1 week after surgery. No patients had any form of permanent iatrogenic nerve damage and a major complication. No failure of instruments was observed.ConclusionsThe hybrid surgery of PTES combined with OLIF and anterolateral screws rod fixation is a good choice of minimally invasive surgery for multi-level LDDs with intervertebral instability, which can get direct neurologic decompression, easy reduction, rigid fixation and solid fusion, and hardly destroy the paraspinal muscles and bone structures.

Anatomic Comparison of Contralateral Maxillary Second Molars Using High-Resolution Micro-CT

The present study aimed to measure and compare anatomic parameters in contralateral maxillary second molars. A total of 18 intact maxillary second molar pairs (n = 36) extracted from 18 patients were scanned with micro-computed tomography (micro-CT) and then reconstructed. Axial, sagittal, and cross-sectional slices were used to analyze the parameters (lengths, widths, and thicknesses) and evaluate the symmetry of the right and left sides. The number of root canals and their internal patterns were classified following Vertucci’s classification. The number of lateral canals and their locations were also noted. Contralateral second molar pairs demonstrated a high degree of similarity in terms of the linear measurements (lengths, widths, and thicknesses). The root canal anatomy configuration symmetry of mesiobuccal, distobuccal, and palatal roots according to Vertucci’s classification were 41.1%, 88.2%, and 94.4%, respectively. In total, 41.6% of mesiobuccal roots, 2.7% of distobuccal roots, and 30.6% of palatal roots had at least one lateral canal. The apical third (38.7%) was the most frequent location of lateral canals, followed by the middle third (32.3%) of the root. This study provides insight into the anatomy of the root canals of contralateral maxillary second molars, which is valuable for both practitioners and researchers.

Research on congenital severe-to-profound sensorineural hearing loss associated with central lucency of the bony island of the lateral semicircular canal

Background Central lucency of the bony island of the lateral semicircular canal (LSCC) is commonly found in patients with congenital severe-to-profound sensorineural hearing loss (SNHL). Objective Exploring the significance of bony island lucency of LSCC in congenital severe-to-profound SNHL patients. Material and Methods Retrospective measurements of the inner ear structures were made on axial temporal bone CT scans from 182 (364 ears) congenital severe-to-profound SNHL patients and 50 (100 ears) tympanic membrane perforation (TMP) patients. Results The incidence of bony island lucency of LSCC was 46.7% in the congenital severe-to-profound SNHL group and 0% in the TMP group. There was a statistically significant difference in inner ear structures among congenital severe-to-profound SNHL patients with normal inner ear structure and bony island lucency of LSCC, congenital severe-to-profound SNHL patients with normal inner ear structure and no bony island lucency of LSCC, and TMP patients. The importance of the bony island lucency of LSCC was further confirmed through multiple linear regression analysis. Conclusions and Significance Bony island lucency may have significance in congenital severe-to-profound SNHL and may be a manifestation of largely overlooked SCC malformation or hypoplasia of the inner ear.

Clinical identification and endodontic management of furcation canals: a case series.

In the case of endodontic infection, the presence of furcation canals can be at the origin of a periodontal lesion located in the furcation. The furcation being very close to the marginal periodontium, this type of lesion can be favorable to the genesis of an endo-periodontal lesion. These furcation canals are lateral canals located on the pulp chamber floor and constitute one of the many physiological communication pathways between endodontic and periodontal tissues. These canals are most often difficult to localize, shape, and to fill because of their small diameter and length. The disinfection of the pulp chamber floor with sodium hypochlorite solution may contribute to the disinfection of furcation canals when they are not identified, shaped, and/or filled. This case series illustrates the endodontic management of visible furcation canals associated with an endo-periodontal lesion. These furcation canals had a large diameter which allowed their identification during the endodontic treatment.