Accessory Canals Research Articles

Cone-beam computed tomography of accessory canals of the canalis sinuosus and analysis of the related risk factors.

Cone-beam computed tomography (CBCT) was used in this study for evaluating the diameter, prevalence, spatial location, and risk factors of the accessory canal (AC) of the canalis sinuosus. A comprehensive assessment of the incidence rate, diameter, three-dimensional (3D) spatial location, and direction of travel of AC was performed on 1003 CBCT images. The CBCT data were used to reconstruct a 3D model of the maxilla to determine the alveolar bone volume. The obtained data were further analyzed and processed. AC was present in 50.1% of images. Male patients more frequently had ACs than female patients did (P < 0.01) and was positively correlated with the maxillary alveolar bone volume (P < 0.001, OR 1.532). Age or nasopalatine canal diameter were not significantly associated with the occurrence of AC (P > 0.05). Among the 502 patients with AC, AC was present on the left side, right side, and bilaterally in 189, 98, and 215, respectively. The maximum number of ACs observed per individual was eight. The average AC diameter was 0.89 ± 0.26mm (minimum, 0.5mm; maximum, 2.02mm). As the prevalence of AC and its trajectory display considerable variation among individuals, surgeons must consider the possibility of the presence of AC when devising surgical plans involving the anterior maxillary region.

Accessory optic canals and a caroticoclinoid foramen in an infant: considerations for anterior clinoidectomy in the pediatric population

Abstract: Anterior clinoidectomy is a routine neurosurgical procedure for the management of paraclinoid aneurysms and tumors in adults; however, it has been performed less extensively in children. The anterior clinoid process of the sphenoid bone is closely related to vital neurovascular structures including the optic nerve, internal carotid artery, and the ophthalmic artery. Therefore, sphenoidal variants, such as the accessory optic canal and caroticoclinoid foramen, pose serious complications in anterior clinoidectomy including potential blindness and death. Case report: This report presents a novel case of concomitant bilateral accessory optic canals and a right-sided caroticoclinoid foramen found within an infantile sphenoid of a 12-month-old black male. The case report documents two co-occurring, clinically relevant variants known to complicate anterior clinoidectomy in an individual from a population that has been underrepresented in the literature. Conclusion: Caroticoclinoid foramina and accessory optic canals can be mistaken for each other on preoperative imaging, and accessory optic canals can additionally be mistaken for pneumatization of the anterior clinoid process, lesser sphenoidal wing, or optic strut. A high index of suspicion for these anatomic variants on preoperative imaging could enable the prevention of adverse outcomes, including hemorrhaging of the internal carotid artery and/or ophthalmic artery and subsequent blindness or death.

A cone-beam computed tomography study of canalis sinuosus and its accessory canals in a South African population.

Canalis sinuosus (CS) is a clinically relevant structure in the anterior maxilla. The present study aimed to determine the prevalence and distribution of CS and its accessory canals (ACs) in the South African population and describe its anatomical variations. In total, 500 cone-beam computed tomography (CBCT) scans of the anterior maxilla were assessed for prevalence, sidedness, diameter, and distribution of CS. The frequency, number, diameter, configuration, and point of termination of ACs were also recorded. Statistical analysis was performed using analysis of variance, Kruskal-Wallis, chi-squared, and Fisher Exact tests with P < 0.05. CS was present in most cases (99.6%), and commonly occurred bilaterally (98.8%). The mean diameter of CS was 1.08mm (range: 0.50mm-2.39mm). Sex, population group, and age had no significant effect on the prevalence or sidedness of CS. Additionally, 535 ACs were observed in 58.8% of the sample, with 42.9% of ACs found bilaterally and 57.1% unilaterally. The mean diameter of the ACs was 0.86mm on the left and 0.87mm on the right (range; 0.50mm-1.52mm). The majority of ACs maintained a straight vertical configuration (72.3%). ACs most commonly terminated in the anterior palatal region of the maxilla (57.2%). No significant differences were found in any groups mentioned (P > 0.05). A high prevalence of CS as well as ACs were observed in thesample population. Due to their clinical significance, surgical planning with the aid of high quality CBCT scans of the anterior maxilla is advisable.

Micro computed tomography (Micro-CT) characterization of root and root canal morphology of mandibular first premolars: a systematic review and meta-analysis

IntroductionMandibular first premolars are familiar with their varied root canal morphology, causing difficulties and challenges for successful endodontic procedures. This systematic review and meta-analysis aim to study the characterization of root and canal morphology of the first mandibular premolar using micro-computed tomography.MethodologyThe literature search was conducted using electronic web databases like PubMed, Scopus, ScienceDirect and Cochrane with the chosen MeSH key words and data was retrieved until May 2023. Further to perform the statistical analysis, R v 4.3.1 software with "meta", 'metafor" "metaviz" " ggplot2" package was used, and results were represented by odds ratios (OR) and the percentage of forest plots along a 95 per cent confidence interval (CI).ResultsThe total number of studies meeting the inclusion criteria was 13; these studies were conducted on mandibular first premolar using Micro-CT; the total sample size was 1817. To scan the sample, an X-ray micro-focus CT system (Siemens Inveon CT, Erlangen, Germany) was used in four studies and seven different machines were used in the respective studies. Mimics 10.01 software (Materialize, Leuven, Belgium) and NRecon v.1.6.9 software (Bruker, Kontich, Belgium) were commonly operated. The minimum and maximum voxel size ranges between 11.94 and 50 μm. Vertucci’s classification was frequently used (9), while one study applied Ahmed et al. and Vertucci’s classification.ConclusionThis systematic review provides essential information about the root and canal configurations, radicular grooves, accessory canals, and apical foramina through Micro-CT, aiming to improve the accuracy of endodontic treatment and help practitioners.

Controversial terminology in root and canal anatomy: A comprehensive review.

Discipline-specific terminology is a central element of the vocabulary used by dentists and scientists in the context of their professional activities and plays a critical role in the understanding of dentistry. A number of controversial terms and non-standardized definitions exist in the field of endodontology. For example, in root and canal anatomy, variations exist in the definitions of root morphology (including apical bifurcation, fusion and dilaceration), pulp chamber anatomy (including the outline of the floor, pulp horns and location of the root canal orifice), apical root canal bifurcations, canal isthmuses, accessory canals and apical foramen. This narrative review provides a critical analysis of a range of controversial terms currently used to describe root and canal anatomy. It also addresses the consequences of using such controversial terms on the accuracy and reliability of research findings and clinical practice.

Performance of obturation techniques in anatomical irregularities located at different thirds of the root canal system.

This study aimed to compare the quality of root canal obturation (ratio of area occupied by gutta-percha (G), sealer (S), and presence of voids (V)) in different anatomical irregularities (intercanal communications, lateral irregularities, and accessory canals) located at different thirds of the root canal system of mandibular molar replicas. Sixty-seven 3D printed replicas of an accessed mandibular molar were prepared using ProGlider and ProTaper Gold rotatory systems. Three specimens were randomly selected to be used as controls and did not receive further treatment. The rest were randomly distributed in 4 experimental groups to be obturated using either cold lateral compaction (LC), continuous wave of condensation (CW), and core-carrier obturation (ThermafilPlus (TH) or GuttaCore (GC)) (n=16 per group). AHPlus® sealer was used in all groups. The three controls and a specimen from each experimental group were scanned using micro-computed tomography. The rest of the replicas were sectioned at the sites of anatomical irregularities and examined at 30× magnification. The G, S, and V ratios were calculated dividing the area occupied with each element by the total root canal area and then compared among groups using the Kruskal-Wallis test. Voids were present in all obturation techniques with ratios from 0.01 to 0.15. CW obtained a significantly higher G ratio in the irregularity located in the coronal third (0.882) than LC (0.681), TH (0.773), and GC (0.801) (p<0.05). TH and GC achieved significantly higher G ratios in those located in the apical third (p<0.05). The worst quality of obturation was observed in the loop accessory canal with all obturation techniques. Whitin the limitations of this study, it can be concluded that CW and core-carrier obturation are respectively the most effective techniques for obturating anatomical irregularities located in the coronal and the apical third.

A Rare Case of Radicular Cyst in the Maxillary Sinus Masquerading as Mucous Retention Cyst

Abstract Cysts are pathological cavities lined by the epithelium that contains fluid or semifluid material. The term “odontogenic cyst” refers to the cyst related to the teeth. One of the most common odontogenic cysts, the periapical cyst, also known as the radicular cyst, is linked to a dead or nonvital tooth. Most often, the apices of the affected nonvital teeth serve as the epicenter of these cysts, although they can also be discovered on the lateral aspects of the roots in connection with lateral accessory root canals. There is something provocative about them. Most radicular cysts are small, but on rare occasions, they may enlarge to the point where they press against the maxillary sinus. In this instance, you can distinguish between pathology coming from the maxillary sinus itself and pathology with an odontogenic origin that is causing the sinus to be displaced by performing a comprehensive examination in conjunction with computed tomography (CT) imaging. This article highlights the use of advanced 3D diagnostic technologies like CT that details the care of a rare case of a huge radicular cyst involving the maxillary sinus in a 50-year-old female requiring surgical intervention.

A micro-computed tomographic evaluation of maxillary first molar accessory root canal morphology in a Black South African subpopulation.

The aim of this study was to investigate the accessory root canal morphology of maxillary first molars in a Black South African subpopulation. Micro-computed tomography was used to investigate 101 maxillary first molars (from 50 male and 51 female teeth, right 53 teeth, left 48 teeth). The prevalence of chamber canals, and the number, type and location (root third) of accessory canals were recorded. The relationships between arch side, sex and age were examined using chi-squared tests of association. Intra- and inter-observer reliability were assessed using Cohen's kappa test. Intra- and inter-rater agreement was 96.9% and 98.1%, respectively. Variations in accessory root canal anatomy according to side, sex and age were evident. Chamber canals were identified in 10.9% of teeth. Accessory canals were found mainly in the apical third of most teeth in the sample, and distributed predominantly in the mesio-buccal root. Apical deltas were most prevalent in the mesio-buccal root, and their frequency decreased in the palatal and then finally the disto-buccal root. Accessory root canals were common in this population, and showed a diverse range of anatomy. The present findings will be of assistance to clinicians during endodontic treatment and will also be valuable for educational purposes.

Comparison of Root Canal Morphology in Intraoral Periapical Radiographs and Cone-Beam Computed Tomography: An In vitro Study

Backgrounds and Objectives: Intraoral periapical radiographs (IOPAR) are routinely used to fulfill the preoperative, par-operative and postoperative imaging needs in endodontic treatment. IOPAR is not a sensitive tool for identification of complex root canal morphology with failure rates of up to 34%. Cone-beam computed tomography (CBCT) provides three-dimensional imaging and has been recommended when endodontic imaging needs cannot be met by IOPAR. There is a need to understand which anatomic parameters are better viewed in CBCT and which on IOPAR. Hence, this study is planned to compare the root canal morphology on IOPAR and CBCT and correlate with chemically cleared tooth. Methods: One hundred recently extracted teeth were collected and subjected to IOPAR and CBCT scanning. A total of six root canal morphologies were compared in both the imaging modalities and with the teeth itself after making it chemically transparent. Results: CBCT and IOPAR showed a good agreement in detection of fractured tooth roots with P &lt; 0.005. However, CBCT was better than IOPAR in detection of the number of accessory canals, ramifications, and obliterations in the root canal and fractures with P &lt; 0.005. IOPAR showed reduced artifacts with P &lt; 0.005. During working length measurement, both CBCT and IOPAR showed increased values than the cleared teeth although CBCT was more accurate. Conclusion: We can conclude from this study CBCT is more accurate in detection of root canal morphologies in comparison to IOPAR.

Morphometric micro-CT study of contralateral mandibular incisors

ObjectivesThis study aimed to determine the degree of similarity and symmetry in the anatomy of contralateral mandibular incisors. Three-dimensional (3D) models of extracted teeth were obtained from microtomography (micro-CT) scans. Qualitative and quantitative assessments of the morphology and comparison of contralateral pairs were made. The null hypothesis was that contralateral mandibular incisors could not be considered identical in simple morphometric measurements.MethodsSixty pairs of mandibular incisors were extracted from 30 patients and scanned with micro-CT. Virtual models of the cemento-enamel junction to the root apex were rendered. Parameters such as length, canal width, dentinal thicknesses, tortuosity, centerline length, accessory canals, root canal configurations, and root canal orifice cross-sections were used to compare the teeth. Width and thickness comparisons between paired teeth in the same individual were made by paired t-test (Wilcoxon signed-rank test for variables not normally distributed). An online randomization tool generated randomized pairs (independent of the individual/patient). Subsequently, an unpaired t-test (or Mann–Whitney U test for non-normally distributed parameters) and a correlation analysis were conducted. Canal configurations were classified according to preexisting classification schemes. The number and location of accessory canals and apical foramina were registered and compared.ResultsUtilizing advanced imaging techniques and quantitative analyses, our study establishes that contralateral mandibular incisors exhibit a remarkable degree of symmetry in multiple morphological parameters, including length, canal width, and dentinal thicknesses. The apical third showed a high degree of inter-variability for the contralateral pairs. The rigorous statistical analysis of the normalized parameters by Z-score showed no statistically significant differences between the contralateral mandibular incisors. Comparisons between central and lateral teeth revealed differences in root length but no significant disparity in the distribution of accessory canals. Central teeth, on average, were longer, while accessory canals were distributed relatively evenly between central and lateral teeth.ConclusionsThe findings of this study further establish the significant similarities between contralateral mandibular incisors, reinforcing their suitability as a reliable substrate for root canal comparison studies.Clinical relevanceThe absence of statistically significant differences between contralateral pairs in normalized parameters underscores their potential as a reliable reference point for root canal comparison studies in clinical dentistry. Furthermore, our findings emphasize the importance of individualized treatment planning, considering the natural symmetry in mandibular incisors to enhance clinical decision-making. This research contributes valuable insights to the field of endodontics, offering a standardized approach to sample selection and enriching the understanding of dental anatomy.

Internal Morphology of Mandibular Second Premolars Using Micro-Computed Tomography.

To examine root canal morphology of mandibular second premolars (Mn2P) of a mixed Swiss-German population by means of micro-computed tomography (micro-CT). Root canal configuration (RCC) of 102 Mn2P were investigated using micro-CT unit (µCT 40; SCANCO Medical AG, Brüttisellen, Switzerland) with 3D software imaging (VGStudio Max 2.2; Volume Graphics GmbH, Heidelberg, Germany), described with a four-digit system code indicating the main root canal from coronal to apical thirds and the number of main foramina. A total of 12 different RCCs were detected. 1-1-1/1 (54.9%) was most frequently observed RCC, followed by 1-1-1/2 (14.7%), 1-1-2/2 (10.8%), 1-2-2/2 (4.9%), 1-1-3/3 (3.9%), 1-1-1/3 (2.9%), 2-1-1/1 (2.9%) and less frequently 1-1-2/3, 1-2-1/2, 2-1-2/2, 1-1-2/5, 1-1-1/4 with each 1.0%. No accessory foramina were present in 35.3%, one in 35.3%, two in 21.6%, three and four in 2.9%, and five in 2.0%. In 55.9% Mn2Ps, accessory root canals were present in apical third and 8.8% in middle third of a root. Connecting canals were observed less frequently (6.9%) in apical and 2.9% in the middle third, no accessory/connecting canals in coronal third. Every tenth tooth showed at least or more than three main foramina. Almost two thirds of the sample showed accessory root canals, predominantly in apical third. The mainly single-rooted sample of Mn2Ps showed less frequent morphological diversifications than Mn1Ps.

Optic Canal Size is an Indicator for the Accessory Optic Canal: Applications for Anterior Clinoidectomy

BackgroundThe ophthalmic artery normally travels with the optic nerve through the optic canal. However, sometimes, the ophthalmic artery travels through a foramen within the optic strut named an accessory optic canal, double optic canal, or ophthalmic canal. This variant puts individuals at an increased risk for blindness or death during anterior clinoidectomy due to unforeseen hemorrhage of the ophthalmic artery or internal carotid artery when the optic strut is separated from the body of the sphenoid bone. Several features make the accessory optic canal difficult to recognize on imaging: its variant nature, small size, and ability to masquerade as a caroticoclinoid foramen or a pneumatized sphenoidal structure. Hence, improved methods of presurgical identification are warranted. The aim of this study was to assess the size and shape of the optic canal, with and without a concomitant accessory optic canal, to determine whether measurement of the optic canal may provide useful information regarding the presence of an accessory optic canal. MethodsIn 191 dry crania, optic canals with and without concomitant accessory optic canals were assessed for the following parameters: canal area, canal perimeter, circularity, solidity, the axes and aspect ratio of a best fit ellipse, and roundness. ResultsNormal optic canals were found to have a larger area (p=0.036), perimeter (p=0.043), and minor axis of a best fit ellipse (p=0.031) than the optic canals that occurred alongside accessory optic canals. ConclusionsAsymmetry in optic canal size can help indicate the presence of a unilateral accessory optic canal prior to surgery.

CBCT and Micro-CT analysis of the mandibular first premolars with C-shaped canal system in a Chinese population author

ObjectivesThe purpose of this study was to survey the prevalence of C-shaped root canal system in mandibular first premolar in Chinese population by reading Cone-beam computed tomography (CBCT) images and to analyze its anatomical characteristics by CBCT and Micro–computed tomography (Micro-CT).Methods and materialsThe prevalence and the morphologic features of C-shaped root canal system were evaluated by observing CBCT images of 760 patients (1520 mandibular first premolars). 66 mandibular first premolars with C-shaped root canal system were scanned by Micro-CT. The morphologic features including radicular groove, C-shaped root canal categories in the cross-sections and in the 3D models, accessory and connecting canals, apical foramina and accessory foramina, were analyzed using image software.ResultsC-shaped root canal system was identified in 16.9% of mandibular first premolars. The minimum mesial wall thickness most commonly occurred at the lingual site (69.7%). Regarding to the cross-sectional classification, the maximum was C2 (41.5%). In the 3D classification, the most common was S (34.8%). Accessory canals were observed in 36.4% of the samples and occurred mostly in the middle and apical regions. 42.4% samples had 1–3 variable connecting canals, and 40.9% samples had only one apical foramen.ConclusionsThe incidence of C-shaped root canal system in mandibular first premolars was 16.9% in the Chinese population. The anatomy was very complex and variable, mostly distributed in the middle and apical regions of the root canal. The mesial wall of C-shaped canal was extremely thin on the lingual side.

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.

A Cone-Beam Computed Tomographic Analysis of Mesiobuccal Root Canals of Maxillary First Molars.

The maxillary first molar is crucial for proper bite formation and jaw positioning in adulthood. The prevalence of dental caries in the study's sample population suggests it is a common candidate for endodontic therapy. Multiple studies have shown that the canal and root morphology of the maxillary first molar are abnormal. The distobuccal and palatal roots of 286 maxillary first molars were removed at the furcation. The mesiobuccal roots were then imaged using cone-beam computed tomography (CBCT) on all specimens. The specimens were analyzed in comparison with one another. The following factors were studied. The number and arrangement of canals, as described by Vertucci; the presence or absence of an isthmus, as described by Kim; the canal curvature angle, as measured by the Schneider method; characteristics such as calcified segments, lateral canals, and an apical delta.For the flow analysis, CBCT was utilized to examine the root channel architecture of 286 mesiobuccal (MB) permanent maxillary first molar. Type I canal arrangement was found in 51.6% of teeth, Type II in 33.3%, Type III in 4.6%, Type IV in 4.2%, Type V in 2.5%, and Type VII in 1.5%. Type I, II, III, and V isthmus were each present in 26%, 6.7%, 9.5%, and 10.2% of the samples, respectively. Teeth with MB1 canal angulations of 0-20 degrees, 21-40 degrees, and more than 40 degrees were found in 56, 188, and 41 teeth, respectively. From 0 to 20 degrees, 21 to 40 degrees, and more than 40 degrees, 15 teeth, 88 teeth, and 25 teeth, respectively, had angulations in their MB2 canals. Only 9.8% of the samples had lateral canals, while 16.1% had both accessory canals and apical deltas. There were 19 cases with calcified segments in the coronal third of the MB1 canal and 13 cases in the middle third. There were no calcifications at the distal end of the MB1 canal. Thirteen of the specimens showed calcification only in the most caudal third of the MB2 canal, whereas the middle and distal thirds were uncalcified. Utilizing a noninvasive approach, a CBCT scan has the capacity to provide valuable insights into the root canal configuration.

Ex vivo detection of mandibular incisors’ root canal morphology using cone-beam computed tomography with 4 different voxel sizes and micro-computed tomography

BackgroundIn recent years, cone-beam computed tomography (CBCT) has been widely used to evaluate patients’ root canal anatomy due to its high resolution and noninvasive nature. As voxel size is one of the most important parameters affecting CBCT image quality, the current study evaluated the diagnostic potential of CBCT with 4 different voxel sizes in the detection of double root canal systems and accessory canals (ACs) in permanent mandibular incisors.MethodsA total of 106 extracted mandibular permanent incisors were collected from the dental clinics, and then were scanned by using micro-CT with a voxel size of 9 μm. The teeth were then fixed in the tooth sockets of human dry mandibles and scanned by using a CBCT device with 4 different voxel sizes (300, 200, 250, and 125 μm). Four observers detected in blind the root canal morphology of the teeth according to the CBCT images, and the presence or absence of a double root canal system, and the presence or absence of ACs, were scored according to a 5-point scale, respectively. Receiver operating characteristic (ROC) analysis was performed, and DeLong test was used to compare the area under the curve (AUC) values and the micro-CT data was taken as a gold standard.ResultsAmong 106 sample teeth, 25 specimens with a double root canal system were identified by the micro-CT. ROC curve analysis of the data obtained by the four observers showed that in the detection of double root canal systems, the AUC values ranged from 0.765 to 0.889 for 300 μm voxel size, from 0.877 to 0.926 for 250 μm voxel size, from 0.893 to 0.967 for 200 μm voxel size, and from 0.914 to 0.967 for 125 μm voxel size (all p < 0.01). In general, we observed a trend that the AUC values, sensitivity, and specialty increased with the decrease in the voxel size, and significantly higher AUC values were detected in 125 μm voxel size images. In the detection of ACs, ROC curve analysis showed that among the four observers, the AUC values ranged from 0.554 to 0.639 for 300 μm voxel size, from 0.532 to 0.654 for 250 μm voxel size, from 0.567 to 0.626 for 200 μm voxel size, and from 0.638 to 0.678 for 125 μm voxel size. CBCT images at a voxel size of 125 μm had a weak diagnostic potential (AUC: 0.5–0.7, all p < 0.05) in the detection of AC, with a lower sensitivity ranging from 36.8 to 57.9% and a higher specialty ranging from 73.6 to 98.8%.ConclusionsCBCT with 300 μm voxel size could only provide moderate diagnostic accuracy in the detection of a double canal system in mandibular incisors. CBCT with a voxel size of 125 μm exhibited high diagnostic value in the detection of double canal systems, while showing low but statistically significant value in the detection of ACs.

Mandibular Canal Branching Assessed With Cone-Beam Computed Tomography.

This study aimed to evaluate the prevalence and type of mandibular canal branching in a sample of the Iranian population through cone-beam computed tomography (CBCT) images. This cross-sectional study was performed on CBCT records of 300 patients (112 males and 188 females; mean age 30.14 ± 10.96 y). The presence of mandibular canal branch (MCB) was evaluated by reconstructing multiple panoramic views and buccolingual cross-sections, according to Naitoh's classification. The prevalence of MCB, the type of MCB, and the demographic information of all patients were recorded. The maximum number of branching and the maximum type of branching were also registered for each patient. Mandibular canal branching was observed in 131(43.7%) of 300 CBCT images without side or sex differences ( P > 0.05). The most frequent type was dental, followed by the retromolar, forward, and buccolingual types, respectively. There was a statistically higher frequency of retromolar canal in females than in males (odds ratio: 1.14 ± 4.25; P = 0.013). About 46% of patients with MCB had more than one accessory canal and 29% displayed more than one type of MCB. The coincidence of dental and retromolar canals in a patient was the most prevalent combination. Considering the relatively high prevalence of MCB (43.7%), it is recommended to keep in mind the possibility of anatomical variations of the inferior alveolar nerve during dental procedures to avoid postsurgical complications. The high possibility of observing multiple numbers and types of branching in the patients should also be considered during preoperative assessments.

Should we be concerned about accessory mandibular foramina and canals? A cone-beam computed tomography study

Objective: Analyze the prevalence of mandibular accessory foramina and canals using cone-beam computed tomography (CBCT). Methodology: 136 mandibles divided into 10 predetermined areas were analyzed through CBCT looking for accessory foramina and canals. The Chi-square and Wilcoxon tests were used. Results: We found 1.316 accessory foramina, which 486 were accompanied by canals. 70.3% of accessory foramina were on the internal mandibular surface, most below the mylohyoid line and genial tubercles. The M1 area had the highest number of foramina, especially in the internal surface. The right mandibular side revealed a significantly greater number of foramina when compared to the left side. The mean diameter of accessory foramina analyzed was 0.85mm. Most of the accessory canals were on the internal mandibular surface, with a longer average length when compared to external surface canals. Conclusion: Our study showed that more detailed studies of accessory mandibular foramina and canals should be carried out, since a high prevalence of these structures and they have not named or classified yet. Furthermore, procedures that reach the internal mandibular surface, especially the anterior region, may be more subject to complications, as well as failure of anesthetic blocks on the right side of the mandible.

Prevalence and characteristics of accessory mandibular canals in an eastern Chinese population by cone beam computed tomography.

This retrospective study aimed to determine the prevalence and morphological characteristics of accessory mandibular canals (AMCs) in an eastern Chinese population to provide clinical guidance for reducing intraoperative and postoperative complications. Cone beam computed tomography (CBCT) scans of 300 Chinese patients were used to identify AMCs according to a modification of Naitoh's classification. The length of the branch (L0) and the upper and lower angles between the branch and mandibular canal were measured on sagittal images. Additionally, the branches were divided into narrow or wide types by calculating the ratio of the branch diameter to the main canal diameter. The location of the bifurcation point was characterized by measuring its distance to the buccal wall of the mandible (L1), lingual wall of the mandible (L2) and alveolar ridge (L3). The prevalence rate of AMCs was 40.7% (95% CI: 35.1-46.3), and the most common type was the retromolar canal, followed by the forward canal, dental canal, trifid mandibular canals (TMCs) or others, inferior canal and buccolingual canal. Twenty-one cases of multiple branches with unusual patterns were observed in the study. The average values of L0, L1, L2 and L3 were 15.05 ± 0.63mm, 5.79 ± 0.14mm, 4.40 ± 0.18mm and 14.61 ± 0.31mm, respectively. The mean upper angle and lower angle were 141.59° ± 2.44° and 50.64° ± 2.57°, respectively. Approximately 20.8% of the branches were defined as wide type, and no statistical significance was found between different types. AMCs are not rare anatomic variations of the mandibular canal in the eastern Chinese population; thus, CBCT examination is highly recommended for precise evaluation before surgeries involving the mandibles.

Stevia vs. triple antibiotic paste: An intracanal battle?

Intracanal medicaments are vital in treating the infections of the deciduous dentition due to the large percentage of accessory canals that hasten the microbial spread to the periradicular region. Though countless medicaments have been produced to reduce the microbial load and aid symptomatic relief, they still do not fulfill every function of an ideal medicament. The aim of the present study was to evaluate and compare the antimicrobial efficacy of Stevia rebaudiana (S. rebaudiana) and triple antibiotic paste (TAP) against Enterococcus faecalis (E. faecalis). The present in vitro, parallel, double-blinded study had an equal allocation ratio. The specimens were prepared, randomly divided into 4 groups and inoculated with E. faecalis (ATCC35550). Following incubation, the first 3 groups were treated with S. rebaudiana, triple antibiotic therapy or carbopol gel, respectively, with the 4th negative control group left untreated. The microbial samples were collected before and after treatment, and the counts of colony-forming units (CFUs) were compared. The results were analyzed using the Kruskal-Wallis, Dunn's post-hoc and Wilcoxon's signed rank tests. The first 2 groups displayed a significant decrease in CFUs after drug application, while the carbopol and control groups showed an exponential increase. There was no statistically significant difference between the stevia and TAP groups (p = 0.630). Stevia gel was comparable to TAP in terms of antimicrobial efficacy, and can therefore be considered a new alternative in intracanal treatment.