Determining the position of the lingula and the mandibular foramen using the antilingula in orthognathic surgery.

BACKGROUND: The antilingula located on the lateral surface of the mandibular ramus has been served as a surgical landmark for the mandibular foramen on the medial surface for decades. However, whether the antilingula truly represents the lingula which is the bony prominence overlapping the mandibular foramen, or the foramen itself, is still unclear. This study thus aimed to examine the position of the antilingula in relation to three reference points: the lingula, the anterior and the posterior borders of the mandibular foramen, as well as to the reference plane used in the inferior alveolar nerve block, and to the posterior border of the mandible. METHODS: This observational study was performed in 113 Thai dry mandibles. The antilingula were identified followed by transferring the reference points to the lateral surface. The distances from the antilingula to the reference points, the reference plane and the posterior border of the ramus were then measured. Chi-square test was calculated for side-dependency of the antilingula. Paired t-test was calculated for difference in measurements in left and right sides. RESULTS: The antilingula could be identified in 92.48% of the mandibles with 86.67 - 90.00% accuracy and 86.67% reliability. There was no significant difference in the presence of the antilingula on left and right sides (p = 0.801). Only 2.5% and 0.83% of the antilingula correspond to the lingula and the anterior border of the mandibular foramen, respectively. However, 85% of the reference points were located within 11 mm radius. The antilingula was found located 2.80 mm inferior to the reference plane and 16.84 mm from the posterior border of the ramus. CONCLUSIONS: The antilingula does not concur with the reference points on the medial surface. Our study also suggests that the safe area for vertical osteotomy is 11 mm posterior to the antilingula or at 30% of the length from the posterior border parallel to the occlusal plane. The use of more accurate techniques in localizing the mandibular foramen combined with the antilingula is more recommended than using the antilingula as a sole surgical guide.

Mandibular canal vs. inferior alveolar canal: Evidence-based terminology analysis.

INTRODUCTION: The mandibular canal, as it was formerly named in Terminologia Anatomica (TA), has also been called the inferior alveolar (nerve) canal in many scientific publications. This study was conducted to investigate how these terms have been understood in different regions and different areas of expertise and to discuss the appropriate future application of the term "mandibular canal." METHODS: A literature search was conducted using PubMed, and articles using different terms for this structure were classified into two groups, inferior alveolar canal/inferior alveolar nerve canal (IAC/IANC) and the mandibular canal (MC). The 50 most recent articles in each group were included. Publication year, journal title, country of the first author, and affiliation of all authors were recorded in both groups for all 100 articles. RESULTS: There was a significant difference between the IAC/IANC and MC groups in the numbers of anatomy journals, other journals, and anatomy affiliations. Turkey published most frequently with a total of 15 articles, followed by Iran with 10 articles, and China/India/United States with seven each. When the six countries of the first author that had three or more publications in each group were compared, only Turkey appeared in both groups; otherwise, different countries were in the two groups. CONCLUSIONS: Based on the results of this analysis, and considering that the tentative new term "inferior alveolar foramen" is used in the latest TA, we suggest that the mandibular canal should be renamed the "inferior alveolar canal."

Mandibular canal versus inferior alveolar canal: A Delphi study.

The general principles of anatomical terminology indicate that the "mandibular canal" should be named the "inferior alveolar canal" as it accommodates the inferior alveolar neurovascular bundles. Therefore, we performed a Delphi study to evaluate the current understanding and use of the terminology in different geographical regions and areas of expertise and to determine the appropriate terminology for this bony canal. A Delphi panel was formed and questions sent and answered via email about: field of expertise (anatomy, oral surgery/oral and maxillofacial (OMF) surgery, oral radiology/OMF radiology, plastic surgery, ENT surgery, or dentistry with the exception of oral/OMF surgery and oral/OMF radiology), years of experience in the field of expertise, country currently working in, "what is the name of the bony canal that contains the inferior alveolar neurovascular bundle," and "what should the structure above be called, in general?" A total of 52 participants responded to the questionnaire. Half or more of the experts in anatomy, oral/OMF surgery, and ENT/plastic surgery considered "mandibular canal" to be the most appropriate name for this bony canal. In contrast, more than half of all experts in oral/OMF radiology and dentistry, that is, most fields of dentistry, considered "either mandibular canal or inferior alveolar canal" to be the appropriate name. The results of the Delphi study and general principles suggest that an alternative term for the "mandibular canal" should be "inferior alveolar canal."

Clinical anatomy of the accessory mandibular foramen: application to mandibular ramus osteotomy.

PURPOSE: An accessory foramen around the mandibular foramen is called an accessory mandibular foramen (AMF). The clinical anatomy of the AMF has not been well described. The aim of this study was to reveal the clinical anatomy of the AMF for a better understanding of its implication during ramus surgeries. METHODS: Twenty-two sides fresh-frozen cadaveric heads with a mean age of 76.2 ± 14.4 years at death underwent dissection. The neurovascular bundles passing through the AMF were observed. Additionally, a hemi-face of a latex injected embalmed cadaver was dissected medially to laterally and the neurovascular bundles of the AMF investigated. RESULTS: A unilateral foramen, bilateral foramina, and absence of foramina were found in 45.4%, 18.2%, and 36.4%, respectively. The origin of the neurovascular bundle entering the AMF was a branch of the maxillary artery in 20% and a tributary of the inferior alveolar vein in 80%. In the latex embalmed cadaver, the AMF was found to contain a branch from the maxillary artery and a tributary of the maxillary vein. CONCLUSION: Given the practical meaning of the specific AMF located in the operative field of the ramus osteotomy, we suggest these be named "foramina for ramus osteotomy."

CBCT study on the relationship between lingula and antilingula position in a Chinese Han population.

OBJECTIVE: The purpose of this article was to assess the anatomical relationship between the lingula and the antilingula by measuring the projection of lingula on the lateral side of the ramus on CBCT. METHODS: This study collected CBCT images of 204 mandibular halves in 102 Chinese patients without any damage. We projected the lingula to the lateral side of the mandibular ramus and examined the distance and position relationship between the projection point and the antilingula using three-dimensional computed tomography (3DCT) created by image software. RESULTS: In 204 sides the antilingula appeared in 92 cases, 52 on right and 40 on left. The antilingula was used as a fixed point, in four cases the lingula projection in the anterior superior part, 38 cases in the posterior superior part, 45 cases in the posterior inferior part and zero case in the anterior inferior part. Scatter plots diagrammatic representation in four quadrants centered on the antilingula showed that 79% cases (73/92) lied in a 90° fan shape ranged in 5-10 mm radius in the posterior superior and inferior quadrant. CONCLUSION: The lingula mainly located in the posterior superior and inferior part from the antilingula in a 90° fan shape ranged in 5-10 mm radius. The osteotomy incision should be avoided in this area.

Determination of mandibular morphology in a TURKISH population with Down syndrome using panoramic radiography.

BACKGROUND: Down syndrome (DS) is by far the most common known chromosomal disorder. Some characteristic features of DS are generalised growth deficiency, craniofacial abnormalities such as mandibular prognathism and underdevelopment of the midfacial region, dental abnormalities such as taurodontism and hypodontia. Individuals with DS have an increased prevalence of periodontal disease compared with age-matched control patients. The aim of the present study is to determine the morphologic features of the mandible among individuals with DS. METHODS: Thirty-four DS patients and thirty four age- and gender-matched control subjects underwent panoramic radiography, which included measurement of the mandibular canal (MC), the mandibular foramen (MF), the mandibular ramus (MR), the distance from the MC to the mandibular lower border (C-MLB), and the distance between the MC and the alveolar crest upper limit (C-AUL). Patients were separated into two groups based on age: < 15 (n = 15) and ≥ 15 (n = 19). In order to determine whether the MF, MR, MC, C-AUL, and C-MLB scores differed according to the groups (DS and control), one-way multivariate analysis of covariance (MANCOVA) was applied in which gender and age were taken as covariates. RESULTS: When the main effect according to the group was examined separately according to each measurement, the MF in the DS group was high with a moderate effect (F = 9207; p = 0.003). MR (F = 40,518; p < 0.001), MC (F = 23,747; p < 0.001), and C-AUL (F = 58,571; p < 0.001) in the DS group were lower with a larger effect. C-MLB did not significantly differ between the groups, and the effect size was quite low (p > 0.05). CONCLUSIONS: Mandibular canal morphology may exhibit anatomical variations in DS. The alveolar bone level may differ from non-DS due to growth development retardation and/or periodontal diseases.

Bilateral 'coronoid foramina' with accessory foramina on the 'lateral aspect of ramus' of mandible: an unseen variance discovery in humans.

The normal flexibility in morphology and topography of body structures may be termed as an anatomical variation. This manuscript, aims to present a unique discovery of 'coronoid foramina' bilaterally along with bilateral accessory foramina over the 'lateral aspect of the ramus of the mandible' which has never been seen or documented in the literature so far in a live patient. It is noteworthy to realize a trait of phylogenetic context in these discoveries.

A simple method to locate mandibular foramen with cone-beam computed tomography and its relevance to oral and maxillofacial surgery: a radio-anatomical study.

PURPOSE: The mandibular foramen (MF) cannot be palpated clinically and its location is variable at the medial surface of mandibular ramus. Nevertheless, determining its exact location is very important to the oral and maxillofacial surgeon for the relevant anesthetic and surgical ramus procedures. The aim of this study was to analyze the position of MF using cone-beam computed tomography (CBCT) to help the surgeon in identifying reliable 'target area' for the inferior alveolar nerve (IAN) block and 'safety zone' for mandibular ramus osteotomies approached extra-orally. MATERIALS AND METHODS: This radio-anatomical study examined all CBCT radiographs for patients treated over 2 years. Distances from MF to the anterior (A) and posterior (P) borders of the ramus, mandibular incisura (MI), mandibular notch (MN), and mandibular occlusal plane (O) were measured by a reliable examiner, followed by calculation of ratios to determine the horizontal and vertical position of MF. Patients' details were then recorded. Student's t test and One-Way-ANOVA test were used to analyze data. RESULTS: A total of 210 CBCT radiographs were included and belonged to 210 subjects; 91 males (43.3%) and 119 (56.7%) females, with mean age (± SD) of 43.70 ± 19.08 years. The horizontal and vertical positions of MF differed significantly (P < 0.001) according to age, but generally calculated at least 40% of AP and MIMN distances from P and MI, respectively. CONCLUSION: This study suggested the '40% rule' to locate the 'target area' for IAN block and 'safety zone' for ramus osteotomies approached extra-orally.

Evaluation of localisation of mandibular foramen in patients with mandibular third molar teeth using cone-beam computed tomography.

BACKGROUND: It is important to know the correct anatomical location of the mandibular foramen to obtain successful anaesthesia of inferior alveolar nerve and to prevent injury to the mandibular vessels and nerve, during a variety of oral and maxillofacial surgical procedures. The aim of this study is to evaluate localisation of the mandibular foramen in patients with the third molars using cone-beam computed tomography (CBCT). MATERIALS AND METHODS: Cone-beam computed tomography was used to determine the location of the mandibular foramen in 67 patients (totally 99 sides) with unilateral or bilateral impacted mandibular third molars. RESULTS: The distance from the posterior border of the mandibular ramus to mandibular foramen did not differ significantly among the other angulations. But the difference between vertical and horizontal angulation of the impacted mandibular third molars according to 'fd' values (the shortest distance between mandibular foramen and the posterior border of mandibular ramus) was found to be statistically significant (p < 0.05). CONCLUSIONS: The present study provides new information to the literature concerning relationship between the location of the mandibular foramen and the mandibular third molars.

Presence of antilingula and its relationship to mandibular foramen-An anatomical study.

Aim: Aim of this study was to evaluate the presence of antilingula and its relationship with mandibular foramen. Materials and Methods: In this study, a total of 50 specimens of dry human hemi-mandibles were studied to analyze the presence and relationship of antilingula to mandibular foramen. A 1-mm fissure bur was used to drill a hole perpendicular to bone from the deepest aspect of the concavity at the center of the mandibular foramen from the medial to lateral side, the drill perforated both the medial and lateral cortex of the mandible. The distance from the antilingula to hole was measured and recorded in both antero-posterior and supero-inferior planes. The data were collected and put to statistical analysis. Results: From this study, it was concluded that the antilingula was present in 90% (n = 45) of mandibles and was absent in 10% (n = 5) of mandibles. Antero-posteriorly, the antilingula was present anterior to mandibular foramen in 22.2% (n = 10) of mandibles, posteriorly in 57.7% (n = 26) of mandibles, and there was complete concordance in 20% (n = 9) of mandibles. The supero-inferior relation shows that antilingula was present superior to mandibular foramen in 97.8% (n = 44) of mandibles, and it was present inferiorly in 2.20 (n = 1) of mandibles. Conclusion: Although vertical ramus osteotomy is not a commonly used procedure in these days. From our study, it was concluded that antilingula was present as an elevation in 90% of cases on the lateral ramus border and the mandibular foramen is present inferior and anterior to the antilingula.

The location of mandibular foramen relative to the occlusal plane: a study on anatolian dry mandible.

Purpose: The study aims to evaluate the location of mandibular foramen (MF) with respect to the occlusal plane (OP) and its location on the ramus using Anatolian dry mandibles. Materials and methods: A total of 115 dry mandibles with mandibular molars were analyzed. The distance between the MF and the OP was examined with a flat metal plate. Group A was above the OP; group L was at level, and group B was below the OP. The distances between the MF and anterior border (A-MF), sigmoid notch (U-MF), posterior border (P-MF), and lower border (L-MF) were measured. The symmetry between the two sides was examined. Pearson chi-square and Student's t-test were performed for statistical analysis. Results: According to the analysis, 50.23% of MF was located below the OP (p<0.05). The mean distances of Groups A and B were 3.45 and 4.78 mm, respectively. There was no difference between the left and right in groups (p>0.05). The distance A-MF was 14.71 mm. There was no statistical difference between the distances A-MF and P-MF or U-MF and L-MF. Conclusion: Half of the MF (50.23%) was located below the occlusal plane with a mean distance of 4.78 mm. It may be helpful to place the needle 3-4 mm above the OP and 1.5-2 mm back of the anterior border to obtain a successful inferior alveolar nerve block. The MF was located at the center of the medial surface of the ramus.

Topography and morphometry of the infraorbital and mandibular foramen of the common sloth (Bradypus variegatus) for use in the application of perineural anaesthesia.

A local anaesthetic block performed in cranial and mandibular foramina contributes towards analgesia and the reduction of systemic anaesthesia in procedures in the oral cavity. However, anatomical differences between in wild animals may require adaptations to the anaesthetic and surgical manoeuvres of the head used in domestic animals. With that in mind, we aimed to describe the topography and morphometry of the infraorbital and mandibular foramina in Bradypus variegatus, to support perineural anaesthetic approaches in the cranio-mandibular region of this species. We demonstrated that in B. variegatus there is no significant variability in the morphometric data, allowing access to the studied foramina to occur in a similar way in adult individuals. Finally, we understand that the techniques for the infraorbital and mandibular foramen needed to be adapted due to the anatomical singularities of the species, which culminated in new reference points for more assertive needle positioning.

Cone Beam CT Assessment of Mandibular Foramen and Mental Foramen Positions as Essential Anatomical Landmarks: A Retrospective Study in Vietnam.

INTRODUCTION: The mandibular foramen (MnF) and the mental foramen (MF) are essential anatomical landmarks that should be considered before any surgical procedures in the mandible. This study aimed to investigate the characteristics of the MnF and MF in relation to adjacent anatomical structures, as well as age and gender differences, using cone beam computed tomography (CBCT) projections. METHODS: The study was conducted from August 2023 to January 2024 at the Can Tho University of Medicine and Pharmacy Hospital, Vietnam. In this retrospective study, 50 CBCT images of Vietnamese patients were randomly taken for various clinical purposes. Furthermore, relevant data, such as gender and age groups, were selected to evaluate the correlations, along with specific inclusion criteria. Patients within the age range of 18-69 with a symmetrical mandible were included. RESULTS: The distance of the MnF-MN was 29.6±5.0 mm (right) and 30.1±4.6 mm (left) in males and 25.0±4.2 mm (right) and 26.3±5.0 mm (left) in females. The distance of the MnF-posterior border of the ramus (P) was 16.2±3.6 mm (right) and 15.0±2.3 mm (left) in males. For females, it was 17.1±2.9 mm (right) and 13.8±1.7 mm (left). The distance of the MF-body mandible (MB) was 15.4±2.4 mm (right) and 15.6±2.0 mm (left) in males and 14.0±2.1 mm (right) and 14.3±1.6 mm (left) in females. The distance of the MF-mandibular midline (MM) was 27.0±2.6 mm (right) and 27.0±2.9 mm (left) in males and 25.3±2.0 mm (right) and 25.1±2.2 mm (left) in females. These distances showed statistically significant differences depending on gender (P<0.05). CONCLUSION: It can be said that CBCT provides comprehensive information about the MnF and the MF for dentists in research and clinical practice.

Positions of the Mandibular Foramen and Canal in Different Skeletal Classes and Implications for Bilateral Sagittal Split Osteotomy.

Objectives: To evaluate the positions of the mandibular foramen (MF) and mandibular canal (MC) between different skeletal classes to highlight the implications for bilateral sagittal split osteotomy (BSSO). Methods: A cross-sectional study was performed using cone-beam computed tomography on 90 patients classified into classes I, II and III. Linear measurements were performed on multiplanar reconstructions as follows: from the MF to the edge of the mandibular ramus (1), to the mandibular notch (2), to the ramus width (3) and to the occlusal plane (4); and from the MC to the alveolar crest (A), to the lower border of the mandible (B) and to the mandibular buccal cortical bone (C). Mandibular thickness (D), width (E) and height (F) of the MC were measured. Intra-class correlation coefficient (ICC) checked the reliability. Two-way ANOVA and Tukey's test were used to compare measurements and classes. Results: Linear measurements 2 presented a statistically significant difference between classes I and II. There was no statistically significant difference between the classes and measurements B, C, D, E and F. Linear measurements A were shorter in class III than in class II. Conclusions: Although most measurements suggest that the BSSO technique does not need to be modified for each skeletal class, measurements from the MF to the mandibular notch in class II and from the MC to the alveolar crest on distal of the second molars in class III could help surgeons to recognize critical regions.

Use of Adult Dry Human Mandibles to Study of Mandibular Foramen from Various Bony Landmarks.

Background: Precise knowledge of the mandibular foramen's location is essential for clinical and surgical procedures, especially the inferior alveolar nerve block. Variability in its position concerning different bony landmarks can significantly impact clinical outcomes. Materials and Methods: This study examined 30 Adult dry human mandibles to determine the mandibular foramen's positions in relation to specific bony landmarks: the occlusal plane, posterior border of the ramus, and lingula. Measurements were obtained using a calibrated digital caliper, and statistical analysis was performed. Results: The study revealed significant variations in the position of the mandibular foramen. In relation to the occlusal plane, the mandibular foramen was found at an average height of approximately 15.2 mm (±2.1 mm). Regarding the posterior border of the ramus, it was situated at an average distance of about 18.5 mm (±3.4 mm). In relation to the lingula, the average distance was approximately 21.8 mm (±4.0 mm). These results underscore the considerable individual differences and anatomical variations in the mandibular foramen's location among the studied specimens. Conclusion: The observed variations in the position of the mandibular foramen emphasize the need for clinicians and surgeons to be cognizant of these differences when performing procedures involving the inferior alveolar nerve block. Understanding these anatomical variations is crucial for enhancing clinical precision, reducing complications, and ensuring optimal outcomes.

Controversies on the position of the mandibular foramen - review of the literature.

Foramen of mandible is the most important point considering the Halsted anesthesia. Position of this foramen seems to be stable, however there are lots of controversies regarded to its position. Based on the current literature authors revised datas from literature considering the location of the mandibular foramen.

An Anatomical Study of Dry Mandibles to Determine the Important Surgical Reference Points in Ramus Osteotomy - An Evaluative Study.

Introduction: The variable relation and clinical significance of mandibular foramen (MF) and Lingula with inferior alveolar neurovascular bundle (IANB) is important for dental surgeons. Knowing the landmarks on the ramus of the mandible is of paramount importance to perform the surgery without causing damage to the neurovascular bundle. Materials and Methods: This study was conducted on 85 dry adult mandibles of unknown sex and age. The distances were measured from the anatomical reference points (anti-Lingula, Lingula and MF) using digital callipers. Results: The distance from the anti-Lingula to the anterior border of the ramus (A) was significantly longer on the right side (14.91 mm) than on the left side (14.5 mm). There was a significant difference in mean distances between the anti-Lingula and MF of both the sides (P ≤ 0.005). No significant difference was noted in the distances between the Lingula and the Anti-Lingula, observed for the posterior (B, P = 0.75) and the inferior margin of the mandible (D, P = 0.54). However we found correlation of vertical distances of anti-Lingula with Lingula and MF exhibited moderate positive correlation. Discussion: The IANB is prone to damage during mandibular surgery. Using anti-Lingula alone as a reference point is not guaranteed, but it is still an important anatomical landmark for the surgeon to operate.

Locating the Mandibular Lingula Using Cone-Beam Computed Tomography: A Literature Review.

This study aimed to review the literature on adult mandibular lingula (ML) locations and related distances determined using cone-beam computed tomography (CBCT). A search was conducted for studies on CBCT using the following databases: PubMed, Web of Science, and Embase. The search results were limited to studies published between 1970 and 2021. The inclusion criteria were the investigation of ML location, CBCT, and participants aged ≥18 years. Eligible studies were examined for the distances from the lingual tip to the anterior ramus border, posterior ramus border, sigmoid notch, inferior ramus border, and occlusal plane. Eight studies on CBCT qualified for inclusion in the study. The mean distances from the ML to the anterior ramus border were 15.57 to 20 mm. In most of these, the ML was located above the occlusal plane. No significant differences were observed in the location and related distances for the ML among patients of different sexes, ethnicities, or skeletal patterns.

A detailed radiomorphometric analysis of the mandibular foramen, lingula and anti-lingula with a special emphasis on mandibular prognathism.

INTRODUCTION: The aim of this study was to evaluate radiomorphometric differences of mandibular foramen (MF), lingula (Li), and anti-lingula (AL) between prognathic and non-prognathic patients, using cone-beam computed tomography (CBCT). METHODS: A total of 228 3D CBCT images of 57 prognathic and 57 non-prognathic patients were retrospectively evaluated. The distances between MF or Li to occlusal plane (OP), anterior border of ramus (AR), posterior border of ramus (PR), sigmoid notch (SN), gonion (Go) and distances Li to MF were measured. The presence of AL, and the distances to Li were also assessed in both groups. RESULTS: In prognathic patients the mean distances of MF-AR and Li-PR were lesser, and Li-OP was greater (p < 0.05). However, distances from MF or Li to the other ramal landmarks were similar in both groups (p > 0.05). Presence of AL was found at 53 sides in prognathic and 20 sides in non-prognathic groups (p < 0.05). The horizontal distance of Li-MF was greater in prognathic patients (p < 0.05). On the other hand, there was no difference between groups regarding the horizontal distance of Li-Al, and the vertical distances of Li-MF and Li-AL (p > 0.05). CONCLUSION: The present study provided valuable data regarding morphological differences of MF-AR, Li-MF and Li-OP, which should be considered in the preoperative assessment of patients with mandibular prognathism. Presence of AL was more common in prognathic patients and mainly located above Li. 3D CBCT applications facilitated assessment of AL and its relationship with Li.

Morphological Study of the Mandibular Lingula and Antilingula by Cone-Beam Computed Tomography.

The patterns of the lingula and antilingula are crucial surgical reference points for ramus osteotomy. Cone-beam computed tomography (CBCT) provides three-dimensional images, and patient radiation dose is significantly lower for CBCT than for medical CT. The morphology of the mandibular lingula and antilingula of ninety patients (180 sides) were investigated using CBCT. The lingula were classified as having triangular, truncated, nodular, and assimilated shapes. The antilingula were classified as having hill, ridge, plateau, and plain shapes. The patients' sex, skeletal patterns (Classes I, II, and III), and right and left sides were recorded. The most to least common lingula shapes were nodular (37.8%), followed by truncated (32.8%), triangular (24.4%), and assimilated (5%). The most to least common antilingulae were hill (62.8%), plain (18.9%), plateau (13.9%), and ridge (4.4%) patterns, respectively. The lingula and antilingula had identical patterns on both sides in 47 (52.2%) and 46 patients (51.1%), respectively. Sex and skeletal pattern were not significantly correlated to lingula and antilingula shapes. No significant correlation was observed between lingula and antilingula shapes.