Mandibular Incisive Canal Research Articles

Imaging Aspects of the Mandibular Incisive Canal: A PROSPERO-Registered Systematic Review and Meta-Analysis of Cone Beam Computed Tomography Studies

This study aimed to perform a systematic review and meta-analysis of the literature on the mandibular incisive canal (MIC) studies using cone beam computed tomography (CBCT). A PROSPERO-registered systematic review (#42017056619) was conducted following the PRISMA statements to summarize current knowledge on the CBCT aspects of the MIC. A search was performed in PubMed's Medline and Scopus databases, without date or language restrictions, using the algorithm {[(Interforaminal region) OR (mandibular incisive channel) OR (mandibular incisive nerve) OR (mental mandible) OR (anterior mandible) (cone beam computed tomography). Also, the references were crosschecked. The Meta-Analysis of Statistics Assessment and Review Instrument and meta-analysis was used to evaluate the selected studies. A total of 410 articles were found, and 25 studies were selected after a two-step selection process. The CBCT systems differed regarding field of view (FOV) (large, n = 3; medium, n = 2; small, n = 4; not informed, n = 16) and voxel size (0.15 to 0.4 mm). Geographically, the studies were distributed across four continents (South America, North America, Asia, and Europe), and there was a statistical significance of studies from the American and Asian continents (P < .0001). From 3,421 CBCT exams, the number of female patients was slightly higher than male, and the mean age ranged from 29.8 to 59.1 years. The overall mean prevalence of MIC was 89.6% ± 15.08%, and bilateral occurrence was statistically significant (P < .0001). The studies using a voxel size lower than 0.3 mm showed the highest mean prevalence (93.88%) in comparison with voxel size described as ≥ 0.3 mm (89.33%). Diameter (0.45 to 4.12 mm) and length (6.6 to 40.3 mm) showed great variability among the included studies. In summary, the results of this systematic review evidenced a high worldwide prevalence of MIC. There was no prevalence of MIC in relation to sex, and its presence was mainly related to adults between the fourth and sixth decades of life. In addition, great heterogeneity of methodologies was observed.

Relationship between mandibular incisive canal and mental foramen using cone-beam computed tomography in a selected Brazilian Amazon population

Introduction: The mandibular canal is an anatomic structure that extends bilaterally from the mandibular foramen to the mental foramen. Objective: To identify the presence, extension, and length of the mandibular incisive canal with a cone-beam computed tomography, and to determine correlations with the positioning of the mental foramen and mandibular canal in a selected BrazilianAmazon population. Material and methods: The measurements of the incisive canal that ends at the mandible’s lower buccal and lingual border, at its initial and terminal portions, were obtained from 95 odontological examinations using cone-beam computed tomography. These measurements were compared with the measurements of the distance between the mandibular canal ending at the same cortices in 2 distinct regions at the mental foramen region. Pearson’s correlation test was used to establish a relationship between these measurements. Results: The mandibular incisive canal’s bilateral identification mean age was of 44.29 ± 11.04 y and the mean length was 10.38 ± 4.01 mm.Moderate correlations were found between the measurements of the mandibular incisive canal, mental foramen, and mandibular canal. Conclusion: The mandibular incisive canal can reach the region of the median line, and it did not present differences between the genders or for the length and distance of the mandibular incisive canal to the cortices ending at the mandible base.

Relationship between mandibular incisive canal and mental foramen using cone-beam computed tomography in a selected Brazilian Amazon population

The mandibular canal is an anatomic structure that extends bilaterally from the mandibular foramen to the mental foramen. Objective: To identify the presence, extension, and length of the mandibular incisive canal with a cone-beam computed tomography, and to determine correlations with the positioning of the mental foramen and mandibular canal in a selected Brazilian Amazon population. Material and methods: The measurements of the incisive canal that ends at the mandible’s lower buccal and lingual border, at its initial and terminal portions, were obtained from 95 odontological examinations using cone-beam computed tomography. These measurements were compared with the measurements of the distance between the mandibular canal ending at the same cortices in 2 distinct regions at the mental foramen region. Pearson’s correlation test was used to establish a relationship between these measurements. Results: The mandibular incisive canal’s bilateral identification mean age was of 44.29 ± 11.04 y and the mean length was 10.38 ± 4.01 mm. Moderate correlations were found between the measurements of the mandibular incisive canal, mental foramen, and mandibular canal. Conclusion: The mandibular incisive canal can reach the region of the median line, and it did not present differences between the genders or for the length and distance of the mandibular incisive canal to the cortices ending at the mandible base.

Analysis of the frequency of visualization of morphological variations in anatomical bone features in the mandibular interforaminal region through cone-beam computed tomography.

The purpose of this study was to analyze the frequency of visualization of anatomical bone features and their possible variations in the mandibular interforaminal region through cone-beam computed tomography (CBCT). This is a cross-sectional study that evaluated CBCT scans of the mandible of 141 women and 61 men, obtained by imaging archives from two private clinics of dental radiology. The study analyzed the frequency of visualization of: lingual symphyseal foramen (LSF), additional mental foramen (AdMF), absence of mental foramen (AbMF), mandibular incisive canal (MIC), and anterior loop (AL). Length measurements for MIC and AL were determined at first and following that the respective distances towards vestibular and lingual cortical walls were also individually verified. Statistical analyses included: Student's t test, Chi-square test, and ANOVA for the evaluation of the anatomical features observed through panoramic and parasagittal images' reconstructions. LSF presence was found in 97%, MIC in 75.9%, AL in 24%, AdMF in 4.7%, and AbMF in 2.5%. Chi-square tests demonstrated value results of p < 0.05 only for the presence of left AL in women when compared to men. Mean values for length measures of MIC and AL were of 10.1 and 2.12mm, respectively. Mean distance from AL towards vestibular and lingual cortical walls was of 2.53 and 4.05mm, respectively. Anatomical variability concerning the mandibular interforaminal region emphasizes the importance of performing CBCT in pre-operative assessment of the mandible for surgical procedures with oral implants.

Comparative Anatomy of Mandibular Neurovascular Canals in Modern Human and Great Apes: A Pilot Study with Cone Beam Computed to Mography

The aim of the present study was to compare mandibular neurovascular canal anatomy in human and great apes by using cone beam computed tomography (CBCT). The anatomical variability of mandibular neurovascular canals (mandibular, incisive and lingual canals) of 129 modern humans and great apes (Homo, Pan and Gorilla) were analyzed by linear measurements on CBCT images. The Kruskal-Wallis non-parametric test and Dunn’s all pairs for joint ranks were applied to compare the variability of mandibular canals among these groups. Human, Chimpanzee and Gorilla groups showed significant differences in the dimensions of the mandibular canal, mental foramen, incisive canal, lingual canal and anterior mandibular bone width. Bifid mandibular canals and anterior loops were the anatomical variations most frequently observed in the Gorilla. Humans had a larger mental foramen and a distinctive incisive canal. The latter could not be identified in the Gorilla group. The variability in the anatomy within mandibles of human and non-human primates, shows different forms in the neurovascular structures. In comparison to the mandible of great apes, the incisive canal is suggested to be a feature unique to the human mandible.

Changes in dimension of neurovascular canals in the mandible and maxilla: A radiographic finding in patients diagnosed with MRONJ.

BackgroundThe aim of this retrospective study was to compare the morphological features of neurovascular canals and foramina of patients with medication-related osteonecrosis of the jaws (MRONJ) and healthy individuals by using cone beam computed tomography (CBCT).Material and MethodsThe CBCT images of 58 patients under bisphosphonate therapy diagnosed with MRONJ and age gender- matched controls were retrospectively evaluated. The diameter of mandibular and nasopalatine canal and mandibular, mental and lingual foramina were measured on several sections of CBCT. The value of mental index (MI) and panoramic mandibular index (PMI) were also assessed.ResultsThe mean value of diametric measurements for all neurovascular canals and foramina in MRONJ patients were narrower than controls. Left mandibular foramen was the most affected area (p<0.001). There were significantly difference in all measurements of mental foramen, lingual foramen and mandibular incisive canal between two groups (p<0.05). PMI of MRONJ subjects were also significantly differences in both sides (p<0.05).ConclusionsIn MRONJ patient, neurovascular canals and foramina are affected due to the alterations in bone remodeling. Therefore, the diametric measurement of neurovascular canals and assessment of MI and PMI on CBCT, is a potentially useful method for detection of early changes associated with bisphosphonate therapy and for predict areas where new necrosis may occur. Key words:Bisphosphonate, MRONJ, CBCT, neurovascular canals, PMI.

Evaluation of the incidence and dimensions of the mandibular incisive canal – aspects of implantological treatment planning

Evaluation of the incidence and dimensions of the mandibular incisive canal – aspects of implantological treatment planning

Assessment of the mandibular incisive canal by panoramic radiograph and cone-beam computed tomography

Background: This study aimed to evaluate the location and characteristics of mental foramen, anterior loop and mandibular incisive canal using cone beam computed tomography (CBCT) and digital panoramic radiograph (DPR). Methods: 430 patients both DPRs and CBCTs scans for the location of mental foramen, anterior loop and mandibular incisive canal visibility were included in this retrospective study. All CBCTs were generated with a cone-beam volumetric tomography device. Results: The mandibular incisive canal (MIC) at least one side in the interforaminal region was detected in 17.7% of panoramic images and 89.1% of CBCT images. There was statistically significant difference between two methods (p=.000) in terms of MICs detection. Conclusion: When planning a surgical operation between the mental foraminas, possibility of the presence of MIC should be taken into consideration. Besides, DPR is not a reliable technique in detecting MIC. In critical situations, use of CBCT is recommended.

Characteristics of intrabony nerve canals in mandibular interforaminal region by using cone‐beam computed tomography and a recommendation of safe zone for implant and bone harvesting

Cone-beam computed tomography can accurately show anatomic structure of intrabony nerve canals in mandibular interforaminal region. The aim was to evaluate the characteristics of intrabony nerve canals in mandibular interforaminal region by using cone-beam computed tomography (CBCT) and determine a safe zone for implant and bone harvesting. Hemimandibles (824) CBCT images were obtained. The length of the anterior loop (AL), the length and diameter of the mandibular incisive canal (MIC) and its spatial distance in various landmarks were measured. The prevalence of the AL was 93.57%, and the MIC was 97.33%. The mean lengths of the anterior extension of the anterior loop (aAL), caudal extension of the anterior loop (cAL) and the MIC were 2.53 ± 1.27 mm, 6.04 ± 1.66 mm, 9.97 ± 5.15 mm, respectively. The MIC was closer to buccal border and inferior margin of mandible. The length of the AL and diameter of the MIC varied with gender. The safe zone recommended for implant surgery is 4 mm anterior and 8 mm inferior to the mental foramen, and 10 mm above the inferior margin of mandible. The chin bone should be harvested at least 10 mm below the tooth apices along with a limited depth of 4 mm.

Study of the mandibular incisive canal anatomy using cone beam computed tomography

The aim of this study was to identify the range of individual variability in dimensions and topography of the mandibular incisive canal (MIC) in vivo. One hundred cone beam computed tomography (CBCT) scans of patients from dental outpatient hospitals of Minsk, Belarus were performed on Galileos GAX5 using standard exposure and patient positioning protocol. Reformatted panoramic and sagittal CBCT images were analyzed. The MIC was visualized in 92% of CBCT images. It was detected in the first premolar root region in 93% of cases, and only in 21% of cases it reached the central incisors root area. The MIC started prior to the mental foramen opening with formation of the anterior mental loop in 48% of cases. The MIC started at the level of the mental foramen or close to it in 52% of cases. The degree of MIC visibility and its internal vertical diameter decreases when it comes closer to the midline of the mandible. The distance from the roots of teeth to the upper wall of MIC increases in the mesial direction, while the position of MIC in relation to the base of the mandible remains virtually unchanged. The MIC can appear in a different length and can reach the level of the root of the central mandibular incisor. Individual topography of MIC should be determined during the preoperative radiological examination and surgical procedures in the anterior region of the mandible.

Prevalence of the inferior alveolar nerve's anterior loop and mandibular incisive canal by use of Cone Beam Computed Tomography (CBCT) in an Iranian population

Prevalence of the inferior alveolar nerve's anterior loop and mandibular incisive canal by use of Cone Beam Computed Tomography (CBCT) in an Iranian population

Mandibular incisive canal in Han Chinese using cone beam computed tomography

The aim of this study was to provide reference information for implantology and chin bone harvesting in people of Han Chinese ethnicity by studying the mandibular incisive canal (MIC) using cone beam computed tomography (CBCT). Fifty subjects were included in the study. CBCT scans were obtained for all subjects, and 22 also underwent panoramic radiography to evaluate the visibility of the MIC. The CBCT data of the 50 subjects were reconstructed to measure MIC diameter, length, and location within the mandible. A MIC was identified in 38.6% of panoramic radiographs, with good clarity in 13.6%, while a MIC was identified in 100% of CBCT images, with good clarity in 63.6%. The diameter of the MIC decreased from origin to end. The left and right average MIC lengths were 17.84mm and 17.73mm, respectively. The MIC was close to the buccal cortical border and lower margin of the mandible. In conclusion, the MIC is an anatomical structure in the mandible that can be identified reliably with CBCT. On insertion, implants should be inclined slightly towards the lingual aspect of the anterior mandible to protect the MIC. The chin bone harvesting depth should be limited to 4mm; the harvesting site can be adjusted to the region above or below the MIC.

Can the Inversion Filter Improve the Visibility of the Mandibular Incisive Canal?

Background:One of the anatomic structures in the mental interforaminal area is the mandibular incisive canal (MIC). Using various manipulation tools in the digital system may affect the visibility of MIC.Objectives:The purpose of this study was to assess the effect of inversion filter (IF) on the visibility of mandibular incisive canal in panoramic radiographs.Patients and Methods:In this cross-sectional study, 2580 digital panoramic images of 18 to 70-year-old patients were inspected for presence of MIC. Visibility of MIC and extension of the canal were registered separately on each side using IF and conventional mode. Data were analyzed by Kappa test using SPSS version 20 software. A probability value of P < 0.05 was considered statistically significant.Results:There was no significant differences between IF and conventional mode regarding visibility of MIC (P > 0.05).Conclusion:Although using IF caused improved visibility of MIC, the difference with conventional mode was not statistically different.

Volumetric analysis of chin and mandibular retromolar region as donor sites for cortico‐cancellous bone blocks

To test whether the mandibular retromolar region renders different results from the chin region with respect to the amount of bone available for the harvesting of block grafts. Sixty cone beam computed tomography (CBCT) scans of mandibles of adult patients without pathologic findings in the chin and retromolar region were included. According to the number of mandibular teeth, 20 CBCT data sets were allocated to each of the following groups: group M1: dentition 36-46; group M2: dentition 37-47; and group M3: dentition 38-48. For the potential donor sites in the chin and the retromolar regions, the volume (VChin , VRetro ), the length (LChin , LRetro ), the height (HChin , HRetro ) and the width (HChin , HRetro ) were assessed using a computer software. Moreover, the chin was examined for the presence and the localization of the mandibular incisive canal. To compare the donor sites in the chin and in the retromolar regions, the quotients VRetro /VChin , LRetro /LChin , HRetro /HChin and WRetro /WChin were calculated and tested using the Wilcoxon signed-rank test or the sign test. The mean bone volume VChin measured 3.5±1.3cm(3) (SD), whereas the overall VRetro amounted to 1.8±1.1cm(3) (SD). VRetro amounted to 2.6±1.4cm(3) (SD) in the group M1, 1.8±0.5cm(3) in the group M2 and 1.0±0.4cm(3) in the group M3. For the group M1, VRetro /VChin measured 82±39% (P=0.036). VRetro /VChin reached 57±20% in the group M2 and 32±12% in the group M3 (P<0.001). The mandibular incisive canal was detected in 97% of the CBCT scans. The distance between the mandibular incisive canal and the apices of the central incisors measured 10.5±3.5mm. The amount of bone available for the harvesting of cortico-cancellous blocks in the chin region was superior in comparison with the mandibular retromolar region. In the absence of the second and the third molars, the amount of bone harvestable in the retromolar region reached approximately 80% of the bone volume available in the chin region. In the majority of the cases, the mandibular incisive canal was detected within the donor site in the chin region.

Panoramic radiographs underestimate extensions of the anterior loop and mandibular incisive canal.

PurposeThe purpose of this study was to detect the anterior loop of the mental nerve and the mandibular incisive canal in panoramic radiographs (PAN) and cone-beam computed tomography (CBCT) images, as well as to determine the anterior/mesial extension of these structures in panoramic and cross-sectional reconstructions using PAN and CBCT images.Materials and MethodsImages (both PAN and CBCT) from 90 patients were evaluated by 2 independent observers. Detection of the anterior loop and the incisive canal were compared between PAN and CBCT. The anterior/mesial extension of these structures was compared between PAN and both cross-sectional and panoramic CBCT reconstructions.ResultsIn CBCT, the anterior loop and the incisive canal were observed in 7.7% and 24.4% of the hemimandibles, respectively. In PAN, the anterior loop and the incisive canal were detected in 15% and 5.5% of cases, respectively. PAN presented more difficulties in the visualization of structures. The anterior/mesial extensions ranged from 0.0 mm to 19.0 mm on CBCT. PAN underestimated the measurements by approximately 2.0 mm.ConclusionCBCT appears to be a more reliable imaging modality than PAN for preoperative workups of the anterior mandible. Individual variations in the anterior/mesial extensions of the anterior loop of the mental nerve and the mandibular incisive canal mean that is not prudent to rely on a general safe zone for implant placement or bone surgery in the interforaminal region.

Assessment of mandibular incisive canal using cone-beam computed tomography in Korean population

Purpose: This study was performed to investigate the characteristics of mandibular incisive canal (MIC) in Korean population. Materials and methods: A total of 97 subjects (60 males and 37 females) who underwent cone-beam computed tomography were included in the study. The anatomic features of MIC was assessed according to gender. Length, diameter and distance to inferior, lingual and buccal border were measured at the origin and the terminal. Also the distribution of MIC at each tooth position was evaluated. Results: Of 97 patients included, 75(77.3%) presented bilateral MIC and 13(13.4%) presented unilateral MIC. Of 194 hamimandibles, MIC was detected in 102(85%) sites in male and 61(82.4%) sites in female. Gender and side showed no statistically significant differences in detectability. The length, diameter and distance to adjacent structures were bigger in male than in female except the distance to lingual border. MIC travelled anteriorly in a slightly downward and lingual direction and usually terminated between the first premolar and the canine. On cross-sectional view, MIC showed individually scattered distribution both buccolingually and superoinferiorly. Conclusion: MIC is well detected with cone-beam computed tomography. Considered that the length and the location of MIC has large variations between individuals, its localization using cone-beam CT is highly recommended before performing surgical procedures such as implant placement and bone harvesting.

Characterization of anatomical structures using panoramic X-rays: Part II: Mandibular incisive canal

IntroductionThe mandibular incisive canal (MIC) is the anterior extension of the mandibular canal which contains the mandibular incisive nerve and blood vessels that provide blood supply and innervation to the mandibular anterior teeth. MethodsIn order to determine the detectability, extent, and position of the MIC, conventional panoramic radiographs of 215 Chilean patients were analyzed. ResultsThe MIC was detected in 35.9% of cases, and was more frequently observed in male patients (37.5% in males and 34.7% in females) and on the right side of the mandible (44.6% in the right side and 27.4% in the left side). The results showed a tendency for the detectability of the MIC to decrease with age. The average extensions of the MIC on the right and left sides of the mandible were found to be 8.16mm and 5.58mm, respectively. The average minimum and maximum distances from the lower limit of MIC to the lower margin of the mandible were 11.7mm and 13.2mm, respectively. DiscussionPanoramic radiographs have limited effectiveness when being used to determine the presence, extent, and precise location of the MIC. Since there are significant differences in detectability, length, and path of the MIC between panoramic radiographs and anatomical studies, the use of cone beam (CT) scans is recommended for invasive treatments of the interforaminal jaw area.

Histologic features and fascicular arrangement of the inferior alveolar nerve

ObjectivesKnowledge of the various possible morphologies and courses of the inferior alveolar nerve and artery is important for successful and safe surgical procedures in the mandibular region. The purpose of this study was to verify the histologic features and fascicular arrangement of the inferior alveolar nerve and artery relative to tooth region. Materials and methodsTwenty embalmed dentulous hemimandibles were examined (eight males and two females; mean age, 58.2 years). The hemimandibles were prepared for routine histology and stained with hematoxylin–eosin and Masson’s trichrome. The histologic features, fascicular arrangement, courses, and areas of the inferior alveolar nerve and artery were investigated with the aid of a light microscope. ResultsThe inferior alveolar neurovascular bundle comprised the inferior alveolar nerve, which appeared as a large trunk comprising two major nerves (the mental and dental nerves), and the inferior alveolar artery, which occupied a relatively small portion of the bundle. The mental nerve was located inferolingually in the third molar region and turned to the buccal side in the first molar region, separating from the dental nerve before reaching the mental foramen. The mandibular incisive canal with a bony wall was not found in the lateral incisor region; instead, small dental nerve fascicles and arteries presented consistently in the intertrabecular spaces. The inferior alveolar artery traveled above the inferior alveolar nerve over the entire mandibular canal. ConclusionsThese results provide data that are relevant to treatment planning for operative procedures such as implant placement, endodontic treatment, and osteotomy in the mandibular region.

Measurement of mandibular incisive canal by cone beam CT

Objective This study was conducted to measure the mandibular incisive canal (MIC) by cone beam computed tomography (CBCT) and to assess 3-dimensional structure, course and adjacent structure of the MIC, in order to ensure safe region for surgery of the mandibular interforaminal area. Methods A total of the CBCT images from 83 patients were studied and measured. The detection rates of MIC were calculated The diameter of the MIC and the distances from MIC to the labial and lingual cortices and the inferior border of the mandible and tooth tips were measured at canines and lateral incisors. Results MIC was found in 67.8% of the patients. In the position of canine, the diameter of MIC, the mean distance of the MIC to the tips of the teeth, to the buccal border of the mandible, to the lingual border of the mandible and the inferior border of the mandible were (1.3±0.4), (8.9±2.9), (4.3±0.9), (5.2±1.1) and (8.6±1.5) mm, respectively. In the position of the incisor, the distance of MIC, the mean distance of the MIC to the tips of the teeth, to the buccal border of the mandible, to the lingual border of the mandible and the inferior border of the mandible were (1.0±0.3), (13.3±4.0), (4.2±0.9), (5.9±0.9) and (8.9±1.8) mm, respectively. Conclusion CBCT clearly show three dimensional structure, course and adjacent structure of the MIC. Preoperative CBCT can provide vital information for surgery of the mandibular interforaminal area. Key words: Cone-beam computed tomography; Dental implantation; Mandibular prosthesis implantation; Mandibular incisive canal; Tomography,x-ray computed

Assessment of the mandibular incisive canal using panoramic radiography

Assessment of the mandibular incisive canal using panoramic radiography