Mandibular Foramen Research Articles

Accuracy of Mandibular Foramen Localization Using Digital Orthopantomogram (OPG) in Middle Eastern Population.

Locating the mandibular foramen (MF) through imaging is clinically important for inferior alveolar nerve (IAN) anesthesia and mandibular ramus osteotomies. Although cone-beam computed tomography (CBCT) is superior in imaging the mandible, an orthopantomogram (OPG) is preferred for its ease of use and availability. Therefore, the present study aimed to evaluate the accuracy of digital OPG in localizing the MF, in a subset of the Middle Eastern population. Radiographic images (OPG and CBCT) of selected patients (adults, dentulous and no mandibular abnormalities) were used to locate the MF through digital measurements (mm) of the anteroposterior distance from the anterior border of the ramus (MF-AP) and the superoinferior position from the mandibular occlusal plane (MF-SI). Measurements were statistically compared between OPG and CBCT for accuracy. Differences in measurements between OPG and CBCT were compared against the anatomic location (right/left), age and biological sex, assuming a p-value < 0.05 as significant. A total of 204 radiographic records (males: 100/females: 104/mean age: 34.65 ± 11.55 years) were evaluated. The measurements for the MF were MF-AP-OPG (right: 13.53 ± 2.44/left: 13.19 ± 2.25), MF-AP-CBCT (right: 13.61 ± 2.39/left: 13.36 ± 2.19), MF-SI-OPG (right: 5.25 ± 1.71/left: 5.41 ± 1.65) and MF-SI-CBCT (right: 5.59 ± 1.66/left: 5.52 ± 1.61). Measurements between OPG and CBCT were not significantly different, except for MF-SI (right) (p = 0.042). While the overall difference between OPG and CBCT (MF-AP/MF-SI) measurements showed a significant association (p < 0.01) with the anatomic location (right/left), a significant association (p < 0.05) with biological sex was observed only for MF-AP. Based on this study's outcomes, digital OPG is an accurate modality to locate the MF based on anteroposterior (MF-AP) and superoinferior (MF-SI) measurements. This would be clinically beneficial for dental and oral surgeons to achieve the optimum IAN block anesthesia based on preoperative panoramic radiographs. Similarly, it would assist maxillofacial surgeons in planning mandibular orthognathic surgeries and ramus osteotomies without complications.

Anatomical variations of the human mandible and prevalence of duplicated mental and mandibular foramina in the collection of the State University of Londrina

BackgroundThe knowledge of the morphology of the human mandible is essential for diverse dental procedures. The potential anatomical variations of the bone, including the presence of accessory foramina, may culminate in significant clinical outcomes and implications, directly impacting dental surgery and anesthesia. Aim of studyThis study aimed to evaluate the general morphology of human mandibles in the collection of the State University of Londrina, South Brazil, and to determine the presence of anatomical variations. Materials and methodsA total of 63 mandibles were measured bilaterally with a pachymeter for various dimensions, and a proportional calculation of each parameter was obtained, based on the size of the length of each mandibular base. In addition to the general descriptive morphology of the mandibles, considering that six mandibles presented duplicated foramina, they were divided into two groups, and the mandibles with no anatomical variation (normal group, N = 57) were compared to those with duplicated foramina (N = 6). Data were checked for normal distribution and then tested statistically. ResultsSix out of 63 mandibles (9.52 %) presented duplicated foramina, either mental or mandibular. Significant differences between the normal group and the duplicated foramina group were found in the lengths between mandibular angle and condylar process on both sides (right: 65.14 mm vs. 74.91 mm, p = 0.001; left: 65.04 mm vs. 72.34 mm, p = 0.019); between mandibular angle and coronoid process on the right side (59.55 mm vs. 67.67 mm, p = 0.007); and in the diameter of the left mandibular foramen (3.71 mm vs. 4.64 mm, p = 0.04), with the duplicated foramina group presenting a higher average for all parameters. ConclusionThese findings provide a morphological pattern for the Department of Anatomy of the State University of Londrina collection and highlight the presence of anatomical variations of the human mandible, specifically regarding duplicated foramina. The presence of accessory mental and mandibular foramina is clinically significant for dental procedures, potentially impacting the anesthesia. Understanding these variations is crucial for dental surgeons to prevent complications. Future research should further explore the functional implications and clinical significance of these variations.

Unveiling an uncommon anatomical variation: a case report on mandibular coronoid foramen

Unveiling an uncommon anatomical variation: a case report on mandibular coronoid foramen

Examination of Mandibular Lingual Foramen Variations with Cone Beam Computed Tomography: A Pilot Study

Examination of Mandibular Lingual Foramen Variations with Cone Beam Computed Tomography: A Pilot Study

Evaluation of mandibular trabecular bone by fractal analysis in pediatric patients with hypodontia of the mandibular second premolar tooth

BackgroundIt is still unclear whether the trabecular structure of the jaw is different in individuals with hypodontia than in those without hypodontia; this is important for clinicians. The aim was to determine whether the mandibular trabecular bone structure of children and adolescents with hypodontia differs from the control group by using the fractal analysis (FA) method in this study.MethodsA total of 138 panoramic radiographs of 69 cases and 69 control subjects (mean age 13.2 ± 10.1) were evaluated. The age and gender of subjects in the case and control groups were matched. Three regions of interest (ROIs) were selected from the panoramic radiographs. ROI1 refers to the center of the ramus rising above the mandibular foramen. ROI2 refers to the area between the apical level of the mandibular molar and the upper border of the mandibular canal. ROI3, the missing tooth region, refers to the apical third of the mesial side of the erupting or fully erupted permanent mandibular first molar. Mann-Whitney U and Wilcoxon tests were used. p < 0.05 was accepted for the significance value.ResultsThe mean fractal dimension (FD) values of ROI1, ROI2, and ROI3 were 1,25, 1,20, and 1,13, respectively. The means FD values obtained from the ramus region were higher than the other regions (p < 0.05). The FD values did not differ significantly according to gender and age (p > 0.05). The FD values of the case group were lower than the control group for ROI3 (p < 0.05).ConclusionThe results of this study showed that the mandibular trabecular bone quality of pediatric patients with one missing tooth was different from the healthy group. The difference in the mean FD values from the ROIs indicates that the ramus has a denser structure than the mandibular corpus. Clinicians should factor this into their dental treatment planning process.

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

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). 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. 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. 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.

Determination of Location of Mandibular Foramen of Sri Lankans with Reference to Nearer Anatomic Landmarks by using Dry Mandibles

Objective: The mandibular foramen serves as a reference point in the inferior alveolar nerve block and is at risk in some maxillofacial surgeries. Therefore, it is crucial to localize the position of the mandibular foramen. Worldwide many studies have been conducted regarding this but in Sri Lanka, there aren’t any recorded studies. The objective of this study was to determine the location of the mandibular foramen with reference to nearer anatomical landmarks of the Sri Lankans according to gender.Methods: A total of 20 dry mandibles collected from the Department of Anatomy, Faculty of Medicine, Wayamba University Sri Lanka were included in this study. The distances from the mandibular foramen to 8 bony landmarks were measured using the digital vernier caliper. The data were analyzed using SPSS 23.0 Version. The mean distances were calculated and compared according to gender using the independent samples t-test. The differences in mean measurements between the right and left sides of the mandibles were compared according to gender using the paired samples t-test.Results: There was a significant difference between male and female mandibles in mean distances from the posterior border of the mandibular ramus on the left side, and from the angle of the mandible bilaterally. There was no statistically significant difference between any of the measurements of the right and left sides of the male mandibles, but there was a statistically significant difference in some of the measurements between the right and left sides of the female mandibles. Out of the 40 mandibular foramina observed, there was only one accessory mandibular foramen.Conclusions: According to the study it was proven that there’s a difference in the location of mandibular foramen according to gender. The location of the mandibular foramen in the Sri Lankan population was different from the documented locations of the mandibular foramen of various populations around the globe.

EVALUATION OF THE RELATIVE POSITION OF THE MANDIBULAR FORAMEN IN YEMENI CHILDREN AS A REFERENCE FOR INFERIOR ALVEOLAR NERVE BLOCK USING AN ORTHOPANTAMOGRAPH

Aim and objectives: A crucial component of managing a kid dentistry patient's behavior is pain control. For mandibular teeth, the most used local anesthetic method is inferior alveolar nerve block (IANB). So, an effective IANB anesthetic requires knowledge of the mandibular foramen's location. Using digital panoramic radiography pictures, the mandibular foramen's position in relation to the occlusal plane and the deepest point of the anterior border of the ramus was assessed in a sample of Yemeni children aged 4 to 12. Materials and Methods: This retrospective study consisted of 501 orthodontic charts that were analyzed and divided into three groups: Group 1: 4-6 years, Group 2: 7-9 years and Group 3: 10-12 years. The OPGS were traced directly on radiographic films and measurements were taken from the mandibular foramen to the occlusal level and to the deepest point of the anterior border of the ramus, respectively, on the right and left sides of the mandible. Data were analyzed and the mean and SD were determined and compared for different gender, age groups and side (right/left). Results: Male participants showed slightly higher mean distance values for MF-AB-Right compared to females (16.276±2.03 mm VS 15.952±1.82), but the contrast was not statistically significant. The study found significant differences in the mean MF distances of ABR between the 10-12 year age group and the 4-6 year age group (16.518±1.86 mm VS 15.487±1.95 mm), (p=0.0001). The mean OP-MF distances for the 10-12 year age group were also significant, with significant differences observed in the right side and left side. Conclusion: The results were similar for the total children, regardless of gender. The study suggests that the mandibular foramina position may vary among different age groups. For inferior alveolar nerve block, the needle should be inserted slightly below the OP in 4-6 years old girls and at the same level of OP in 7-9 years old girls, and 4-6 years old boys. Peer Review History: Received 23 March 2024; Revised 6 May 2024; Accepted 29 June; Available online 15 July 2024 Academic Editor: Dr. Asia Selman Abdullah, Pharmacy institute, University of Basrah, Iraq, asia_abdullah65@yahoo.com Average Peer review marks at initial stage: 6.0/10 Average Peer review marks at publication stage: 7.0/10 Reviewers: Dr. A.A. Mgbahurike, University of Port Harcourt, Nigeria, amaka_mgbahurike@yahoo.com Dr. Masoumeh Divar, Shiraz University, Shiraz, Iran, zhaledivar@gmail.com

Topography landmarks of the infraorbital, mandibular and mentual foramens of Saimiri collinsi (Osgood, 1916) for anesthetic access and blocks.

Due to events related to the urbanization process, specimens of Saimiri collinsi are often referred to veterinarians specializing in the treatment of wild animals. With these professionals and the oral health of this species in mind, we evaluated the skull and the exact location of the infraorbital, mentual and mandibular foramens, with the aim of supporting the anesthetic block for dental procedures in Saimiri collinsi. The infraorbital foramen was located in the maxillary bone and was arranged with one on each side, except in one individual, with a pair in each antimer. The mentual foramen was located in the diastema between the canine tooth and the lateral incisor. The mandibular foramen was located medially on the ramus of the mandible, close to the mandibular incisure. The distances between the foramina and the main reference points, were greater in females than in males (p < 0.05). For access purposes, in the foramens investigated we suggest using a Gingival Needle 30G 21mm Short, positioned externally at 15º to the maxillary bone to access the infraorbital foramen. Externally, perpendicular to the chin, in the diastema between the lower lateral incisor tooth and the canine tooth, to approach the mentual foramen, and ventral to the edge of the mandibular body, at a 90º angle, to access the mandibular foramen.

Injury to Anatomic Structures Due to Fixation Device in Management of Mandibular Fracture.

ORIF is the gold standard for the management of mandibular fractures. The chances of postoperative complications are due to infection, damage of the inferior alveolar nerve canal, or tooth root during the fixation of the fracture fragments. Fixation hardware placed in the vicinity of the vital structures may encroach on the anatomic structures, leading to postoperative complications. The aim of this study is to evaluate the injury to the anatomic structures in the proximity of the fracture line due to the fixation device. This retrospective study was conducted in a tertiary care teaching hospital from July 2021 to June 2023. The cases of maxillofacial trauma reported and referred from peripheral centers were considered duly, applying the inclusion and exclusion criteria. Patients having mandibular fractures from one mandibular foramen to another with or without associated other facial fractures were treated by ORIF under general anesthesia. The patient was followed up at 1 week, 1 month, 3 months, and 6 months. The cases of postoperative complications were further investigated by CBCT. There were 67 patients (56 males and 11 females) with 86 fracture lines in the age group of 18-55 years with an average age of 35.2 years. Postoperatively 7 patients presented with unilateral paresthesia of the lower lip and chin region. CBCT revealed that the mean distance of the screw from the inferior alveolar nerve canal was 3.02mm. None of these cases had injury to the nerve canal or roots of teeth. All the patients recovered from paresthesia within 6 months. Complications like injury to the inferior alveolar nerve (IAN) with sensory disturbances to the lower lip and chin, as well as tooth/tooth root fractures, may occur due to mandibular fracture, surgical manipulation, and fixation devices. The anatomic structures in the vicinity of the fracture line can be damaged during the fixation of the fracture fragments by the bone plates and screws. In the present study, it was found that 7 out of 67 patients presented with unilateral paresthesia of the lower lip and chin. CBCT analysis showed a considerable distance of 3.02mm from the inferior alveolar nerve canal to the screws. There was no evidence of hardware encroachment on the IAN or tooth roots. Selection and placement of appropriate fixation devices, particularly the length of the bone screws, are crucial to avoid injury to the anatomic structures.

Assessment of lingula and foramen mandibulae morphology and their implications for inferior alveolar nerve block: a comparative study of contemporary and medieval individuals.

In this study, we conducted a detailed morphological analysis of the lingula and foramen mandibulae, aiming to examine their anatomical characteristics and relationships within contemporary and medieval individuals. Our primary objective was to provide valuable insights to assist clinicians in minimizing potential intraoperative complications during anesthesia procedures targeting the inferior alveolar nerve. To accomplish this, we examined the mandibular structures of 22 adults, 11 children aged 6-12 from archaeological findings in the Târgu Mureș area, and 14 contemporary adults. Our observations encompassed the size, shape, and spatial relationships of the lingula and foramen mandibulae concerning various points along the ascending branch of the mandible. The study revealed a distinct order of lingula shapes among medieval children and adults, with the triangle, trapezoid, nodular, and assimilated shapes being most prevalent. In modern adults, the order of nodular and assimilated shapes was reversed. Additionally, oval foramina were more common in adults, while round foramina predominated in children. Notably, there was no statistically significant difference between children and adults in the distance from the most prominent point of the lingula to the anterior edge of the ascending branch. Our findings imply that the depth at which the inferior alveolar nerve can be accessed remains relatively consistent between children and adults. Furthermore, we identified a correlation between the relationship of the shape of the lingula and the position of the mandibular foramen, providing valuable insights for clinical practice. Keywords: lingula, foramen mandibulae, morphology, inferior alveolar nerve block

Unusually Pronounced and Expansive Mandibular Foramen. A Incidental Radiological Finding

Unusually Pronounced and Expansive Mandibular Foramen. A Incidental Radiological Finding

Location of mandibular foramen in dry mandibles in relation to various anatomical landmarks

To localize the mandibular foramen in dry mandibles of adult and old age groups of South Indian origin by estimating its average distance from different anatomical landmarks and to provide a specific and precise site for inferior alveolar nerve block. : A total of 51 mandibles were taken for the study and the distance between the mandibular foramen and the various anatomical landmarks were measured using a digital vernier caliper. Presence of accessory mandibular foramen was observed and recorded. Difference between the sides and the correlation between the gonial angle and various distances were carried out.:Distance of mandibular foramen from anterior border was 16.41±2.44 mm and 16.85±2.55 mm, from posterior border was 10.28±2.08 mm and 10.13±2.02 mm, from mandibular incisure 22.5±3.13mm and 21.9±3.08mm, from mandibular base 23.72±3.37 mm and 24.5±3.27 mm, from third molar 15.27±11.99 mm and 16.85±11.60 mm, from apex of retro molar trigone 18.28±3.02 mm and 19.79±3.18 mm on right and left side respectively. There was no significant difference between the measurements of right and left sides. The measurements had a negative association with gonial angle. Accessory foramina were found to be present in 21and 23 mandibles on right and left side respectively.:Precise localization of mandibular foramen is clinically very important to achieve effective inferior alveolar nerve block prior to dental surgeries in the lower jaw. The present study establishes the presence of bilateral symmetry in the position of mandibular foramen with respect to various anatomical landmarks and the utility of gonial angle in localizing the mandibular foramen.

Measurement plane of the cross-sectional area of the masseter muscle in patients with skeletal Class III malocclusion: An artificial intelligence model

This study aimed to determine a measurement plane that could represent the maximum cross-sectional area (MCSA) of masseter muscle using an artificial intelligence model for patients with skeletal Class III malocclusion. The study included 197 patients, divided into subgroups according to sex, mandibular symmetry, and mandibular plane angle. The volume, MCSA, and the cross-sectional area (CSA) at different levels were calculated automatically. The vertical distance between MCSA and mandibular foramen, along with the ratio of the masseter CSA at different levels to the MCSA (R), were also calculated. The MCSA and volume showed a strong correlation in the total sample and each subgroup (P<0.001). The correlation between the CSA at each level and MCSA was statistically significant (P<0.001). The peak of the r and the correlation coefficient between the CSA at different levels and MCSA were mostly present 5-10 mm above the mandibular foramen for the total sample and the subgroups. The mean of RA5 to RA10 was>0.93, whereas the corresponding correlation coefficient was>0.96, both for the entire sample and for the subgroups. MCSA could be used as an indicator for masseter muscle size. For patients with skeletal Class III malocclusion, the CSA 5-10 mm above the mandibular foramen, parallel to the Frankfort plane, could be used to estimate the masseter muscle MCSA.

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

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. 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. 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). It can be said that CBCT provides comprehensive information about the MnF and the MF for dentists in research and clinical practice.

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

BackgroundThe 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.MethodsThis 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.ResultsThe 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.ConclusionsThe 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.

Exploring the morphological and morphometric characteristics of the mandibular lingula in dry mandibles of South African population

BackgroundThe lingula of the mandible is a small tongue-shaped bony prominence that partially overlaps the mandibular foramen. It has variable shapes among different populations which impacts its significance as a bony landmark in maxillofacial and oral surgeries. This study aimed to explore the morphological and morphometric characteristics of the mandibular lingula in dry mandibles of a South African population, to provide more knowledge on its structural variations, and location for surgeons involved with maxillofacial and oral surgeries. MethodologyThe study utilized 45 (n = 90 sides) dry human mandibles. The shapes were classified into five types, as per the classification scheme proposed by Tuli et al. (2000) and Varma and Sameer (2013). Three morphometric parameters were utilized to determine the location of the lingula. A p-value of <0.05 was considered statistically significant. ResultsThe most common type of the lingula was the truncated type 36/90 (40%), followed by the triangular type 23/90 (25.56%) and, nodular type 22/90 (24.44%). The mean height (mean ± SD) of the lingula was 7.57 ± 1.56 mm. The mean distance from the lingula to the anterior border of the mandibular ramus was 20.05 ± 3.25 mm while the mean distance from the lingula tip to the posterior border of the ramus of the mandible was 16.58 ± 2.26 mm. The mean distance was 15.81 ± 2.15 mm from the lingula to the mandibular notch. ConclusionThe present study contributes to the existing body of knowledge on the structural variation of the lingula which is important for precise location of the mandibular foramen and related structures, especially when performing any maxillofacial surgical procedures within a South African population group.

Comparative efficacy of digital panoramic radiograph and cone beam computed tomography in locating mandibular foramen.

The aim of this study was to compare the accuracy of panoramic radiographs (PAN) with cone-beam computed tomography (CBCT) in locating the position of the mandibular foramen (MF). A total of 100 patients who underwent CBCT and panoramic imaging were included in the study. The location of the MF was evaluated anterior-posteriorly and superior-inferiorly on both CBCT and panoramic radiographs. Measurements were taken by two examiners, reviewed by a radiologist, and intra-examiner variability was assessed. A comparison of statistical analysis was performed using the Mann-Whitney U test, independent and paired t-test. A p-value ≤0.05 was deemed significant. The mean age of the patients was 35.03 years, with 51% females and 49% males. CBCT and panoramic radiographs showed comparable accuracy in locating the left (p=0.937) and right (p=0.371) MF anterior-posteriorly. In the superior-inferior dimension, the accuracy of CBCT and panoramic radiographs were comparable in locating the right (p=0.292) and left (p=0.640) MF. The gender-based accuracy of PAN and CBCT radiographs in locating the right (p=0.353) and left (p=0.985) MF was comparable. The study concludes that panoramic radiographs showed comparable accuracy in effectively locating MF in comparison to CBCT. The influence of gender and anatomic location (right and left sides of MF) on MF identification with panoramic radiographs was insignificant. Digital panoramic radiographs are an effective tool in accurately identifying MF location in clinical practice.

ANATOMICAL VARIABILITY OF THE SEGMENTS OF THE INFERIOR ALVEOLAR NERVE IN THE PEOPLE OF SECOND PERIOD OF MATURE AND OLDER AGE

To avoid complications of bicortical implantation, great importance is attached to the study of individual morphological features of the mandible and its structures, in particular, the anatomical variability of the inferior alveolar nerve (IAN) and mandibular canal. The purpose of the study was to fi nd out the peculiarities of the structure, topography and individual anatomical variability of the IAN in persons of the second period of maturity and older age. Cone-beam computer tomography of 54 people of both sexes aged 45-65 years with three- dimensional reconstruction, morphometry and statistical analysis was studied. On the basis of our own research on the topographical and anatomical features of the IAN and its syntopy with the mandible, in particular, with the mandibular canal, we propose to distinguish 4 of its divisions: extra- canal – from the place of formation to the entrance to the mandibular canal; intracanal – from the mandibular foramen to the mental foramen; mental – after exiting the mandibular canal; incisive – after the departure of the mental branch. The topographical and anatomical features and anatomical variability of the IAN were studied. In people of the second period of mature and elderly age, anatomical variability of the macroscopic structure and topography of the IAN was established, which manifested itself in high (4.0-11.0 mm) and low (22.0-33.0 mm) levels, relative to the foramen ovale its beginning and form (one or two trunks) of departure from the mandibular nerve. The largest number of nerve connections with other branches of the mandibular nerve is formed by the extracanal section of the IAN: with the auriculo-t emporal nerve (29 cases – 53.7 %), with the lingual nerve (5 cases – 9.26 %), with the nerve of the medial pterygoid muscle (3 observations – 5.56 %) and with the nerve of the lateral pterygoid muscle (2 specimens – 3.7 %). A diff erent level of departure of the nerve to mylohyoid from the extracanal section of the IAN was established: high (5.0-7.0 mm) and low (27.0-31.0 mm). Anatomical variability of the intracanal part of the IAN was manifested by structural variants: a single trunk (43 cases, 79.6 %), rarely – two trunks (11 observations, 20.4 %) and very rarely – the lower dental plexus (6 specimens, 11,11 %). The proximity of the roots of the 7th and 8th teeth to the IAN can be the cause of severe pain in the pathology of these teeth and cause nerve damage during their removal. Nerve connections occur between the right and left incisive nerves, the knowledge of which is an important practical value for performing anesthesia of the front row of teeth. The number of branches to the teeth, interalveolar septa and gingiva from the IAN signifi cantly decreases with age and with a violation of the integrity of the dentition.

Changes in masseter muscle morphology after surgical-orthodontic treatment in patients with skeletal Class III malocclusion with mandibular asymmetry: The automatic masseter muscle segmentation model

This study evaluated the masseter muscle changes after surgical-orthodontic treatment in patients with a skeletal Class III malocclusion using automatic segmentation. Images of 120 patients with skeletal Class III malocclusion were obtained and reconstructed at T0 (pretreatment), T1 (presurgery), and T2 (6-12-month postsurgery). The patients were divided into symmetrical and asymmetrical groups. The volume, major axis length, maximum cross-sectional area, horizontal cross-sectional area 5 mm above the mandibular foramen (CSAF), and orientation were calculated automatically. In the asymmetrical group, the volume and major axis length on the deviated side were lower than on the nondeviated side at T0, T1, and T2 (P<0.05). There were no significant differences in maximum cross-sectional area and CSAF bilaterally. The orientation was coronally more vertical and sagittally more forward on the deviated side (both P<0.001). In the symmetrical group, there were no significant bilateral differences at T0, T1, and T2. The volume, major axis length, and CSAF decreased, and the coronal orientation was more vertical on the nondeviated side at T2 than at T0 in both groups (P<0.05). The coronal plane orientation was more inclined on the deviated side at T2 than at T0 in the asymmetrical group (P<0.05). The smaller volume on the deviated side at T2 indicates the need for myofunctional training after surgery. The masseter muscle volume and the cross-sectional area did not recover to the preorthodontic levels. Studies with longer follow-up durations are needed to confirm these findings.