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Background: The study examines a sample of patients presenting for viscerocranial computer tomography that does not display any apparent signs of asymmetry, assesses the three-dimensional congruency of the mandibular ramus, and focuses on differences in age and gender., Methods: This cross-sectional cohort study screened viscerocranial CT data of patients without deformation or developmental anomalies. Segmentations were obtained from the left and right sides and superimposed according to the best-fit alignment. Comparisons were made to evaluate three-dimensional congruency and compared between subgroups according to age and gender., Results: Two hundred and sixty-eight patients were screened, and one hundred patients met the inclusion criteria. There were no statistical differences between the left and right sides of the mandibular ramus. Also, there were no differences between the subgroups. The overall root mean square was 0.75 ± 0.15 mm, and the mean absolute distance from the mean was 0.54 ± 0.10 mm., Conclusion: The mean difference was less than one millimetre, far below the two-millimetre distance described in the literature that defines relative symmetry. Our study population displays a high degree of three-dimensional congruency. Our findings help to understand that there is sufficient three-dimensional congruency of the mandibular ramus, thus contributing to facilitating CAD-CAM-based procedures based on symmetry for this specific anatomic structure., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 The Authors. Published by Elsevier GmbH.. All rights reserved.)

Objective: The aim of this study was to present an innovative surgical protocol, navigation-based endoscopic enucleation (NBEE) for the treatment of large mandibular cystic lesions involving the mandibular ramus., Methods: Twelve patients who presented with a large mandibular cystic lesion involving the mandibular ramus were enrolled in this study. Preoperative planning and intraoperative navigation were performed in all 12 patients., Results: All patients in this study were treated with navigation-based endoscopic enucleation successfully. The follow-up period ranged from 7 to 10 months. Bone regenerated was found in all patients postoperatively. Three patients experienced temporary mandibular nerve palsy, and all relieved within 2 months. No pathological bone fracture was found during surgery., Conclusions: The use of navigation-based endoscopic enucleation (NBEE) for the treatment of large mandibular cystic lesions involving the ramus proved to be an effective method for complete and precise enucleation of the cystic lesion that also preserved the surrounding tissue., (© 2024. The Author(s).)

Background: The bone thickness of the human mandibular ramus is an important parameter in mandibular surgeries. The aim of this study was to systematically measure the bicortical bone thickness, the ramus dimensions and the position of the lingula. The measurements were tested on significant correlations to the patients' parameters., Methods: Based on CBCT scans 150 rami were reconstructed as 3D polygon surfaces. An anatomical grid was adapted to the ramus surface to mark the bone thickness measurement points and to achieve comparability between the measurements on different mandibles. The bone thickness, ramus height, ramus width and the gonion angle were measured. A cluster analysis was performed with these parameters to identify clinically relevant groups with anatomical similarities., Results: The median distribution of the bone thickness was calculated and visualized in a pseudo-colour map. The mean ramus height was 44.78 mm, the mean width was 31.31 mm and the mean gonion angle was 124.8°. The average distance from the lingula to the dorsal tangent was 53% of the total width and its distance to the caudal tangent was 65% of the total height. Significant correlations between the bone thickness and the ramus proportions could be identified. Age and sex had no significant influence on the mean bone thickness. The measured rami could be divided into two groups by cluster analysis., Conclusion: The dimensions of the human mandibular ramus can be determined from 3D reconstructed surface models from CBCT scans. Measurements could be made comparable by applying an anatomically oriented grid. A cluster analysis allowed the differentiation of two groups with different bone thickness distributions and geometries, which can be used for the optimization of osteosynthesis systems and their precision of adaptation to different ramus morphologies.

Anatomical variations of the mandibular canal as well as the presence of accessory canals and foramina are common findings in the human mandible. Here, we present a previously unreported type of anatomical variation, consisting of a large full-thickness bone defect of the right mandibular ramus, observed in a young male unearthed from a mediaeval cemetery located in North-Eastern Italy. The defect was located very close to, yet not directly connected with, the mandibular canal. Awareness of the existence of deviations from the anatomical norm such as that we describe here is strategic to avoid diagnostic misinterpretations, minimise technical hitches, and prevent clinical complications during invasive procedures in the region of the mandible.

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.

Purpose: The purpose of this study was to investigate the Gonial angle in relation to the position of the lingula using computerized image analysis to guide the oral surgeons to prevent injury to the inferior alveolar nerve and peripheral blood vessels during surgery., Methods: We measured Gonial angle sizes of bilateral rami and the distances from the lingula tip to the mandibular notch (LN), the anterior (LA) and posterior (LP) margin of the mandibular ramus, the mandibular base (LB) and the occlusive plane (h) in 407 Chinese adults with CBCT., Results: In males, the mean distance of LN was 17.64 mm in the low Gonial angle group while 16.76 mm in the high Gonial angle group, which was significantly different between two groups (P < 0.001). The distance of LA in LGA group was obviously longer than that in HGA group (P < 0.001). The mean distance LP of men was 17.94 mm in LGA group while 16.9 mm in HGA group (P < 0.001). In females, the mean distance of LB in LGA group was 33.32 mm and 32.37 mm in HGA group (P < 0.01)., Conclusion: We discovered that the segment of the mandibular branch, between the mandibular lingula and the mandibular angle, was obviously smaller in the HGA group than that in the LGA group.

Background: The identification of an individual from skeletal remains plays a vital role in forensic investigation as it is essential for the identification of the individual's age, sex, and/or race and further analysis. Skeletal characteristics differ from one population group to another since population-specific osteometric standards exist for sex determination. Since the mandible is the largest, strongest and most durable compact facial bone, it is the best preserved after death. While sexual dimorphism of the mandible is indicated by its shape and size, morphometric analysis is more accurate in the determination of sex from the skull. The aim of this study was to evaluate the morphometric parameters of the mandible in the Durban Metropolitan population., Materials and Methods: Various morphometric parameters of the mandible were measured and assessed in 265 digital panoramic radiographs aged between 16 and 30 years (n = 530). Each parameter recorded was statistically analysed using SPSS to determine if a relationship existed between the parameter, and sex and age., Results: In this study the morphometric parameters of the male mandibles were greater than that of the females. This concurred with the findings of previous studies. The length of the mandibular ramus on the right and left sides was statistically significant with sex., Conclusions: This correlated with previous studies, indicating that the length of the mandibular ramus generally has higher sexual dimorphism than any other morphometric mandibular parameter (p = 0.000). However, only the length of the right mandibular body was statistically significant when compared with sex (p = 0.040). The findings of this study may assist forensic investigators, anatomists, anthropologists and maxillo-facial surgeons.

Purpose: The aim of the present study was to morphometrically analyze the mandibular canal through the mandibular ramus by cone beam computed tomography (CBCT) and to relate the findings to performing sagittal split ramus osteotomy., Methods: CBCT of 200 patients were analyzed. Five parameters were measured at the axial scan, from the mandibular foramen to 21 mm below it (3-mm intervals). The canal was classified according to the position within the bone marrow space. Variations were evaluated according to age, sex, side, and number of mandibular teeth., Results/conclusions: The following measurements increased gradually towards the most inferior level of measurement: the total thickness of the mandibular ramus through the center of the mandibular canal, the width of the bone marrow space (both buccal and lingual), and the narrowest width from the mandibular canal inner cortical to the mandibular ramus external cortical. The inner diameter of the mandibular canal slightly decreased to the same direction. Concerning the mandibular canal position within the bone marrow space, the percentage of the separate type increased towards the most inferior level of measurement, and the contact and fusion types decreased. Age, number of teeth, and sex had no significant influence on the total thickness of the mandibular ramus and on the narrowest width from the mandibular canal inner cortical to the mandibular ramus external cortical.

Objectives: To consider the biologic behaviors of keratocystic odontogenic tumors (KCOTs) and ameloblastomas and dentigerous cysts., Methods: A 63-year-old Japanese man presented with swelling and discomfort in the left cheek during jaw movement. Examination revealed a multilocular lesion within the mandible extending from the left second premolar to the left mandibular ramus and coronoid process; the lesion contained a deviated impacted tooth. The tumor had expanded beyond the bone and was invading the masseter and medial pterygoid muscles. Marginal mandibulectomy with a free iliac bone graft was performed., Results: No recurrence was observed during a 7-year follow-up., Discussion: The histopathological diagnosis of the lesion showed it was a KCOT. These tumors usually grow within the bone, causing bone expansion. However, this tumor had expanded beyond the bone and invaded surrounding muscles. Thus, KCOTs can, in rare cases, manifest themselves as described here. Evaluating preoperative images and histopathological findings is important to determine the optimal treatment strategy.

Objective: The purpose of this study was to identify a surgical reference point on the mandibular ramus that can be used during ramus osteotomy to prevent injury to the inferior alveolar nerve., Materials and Methods: A total of 125 subjects' mandibles were analyzed and compared on a three-dimensional (3D) model constructed from computed tomography (CT). 25 volunteer subjects with normal class I occlusion (group I, control), 50 consecutive subjects (25 females and 25 males) diagnosed with mandibular retrognathism (group II), and 50 consecutive subjects (25 females and 25 males) with prognathism (group III) were included. This study created a landmark (the midwaist point) at the halfway point on a horizontal plane between the most concave points on the anterior and posterior borders of mandibular ramus, with the vertical plane bisecting the horizontal plane. The midwaist point was compared to other anatomic landmarks including antilingula, lingula, and mandibular foramen for correlation., Results: The distance from the midwaist point to lingula and mandibular foramen along the horizontal plane was not significantly different among three groups. Lingula and mandibular foramen were mostly located within 2 mm posterior of the midwaist point, whereas the locations of lingula and mandibular foramen along the vertical plane to the midwaist point were highly variable., Conclusion: The midwaist point is an excellent intraoperative reference point that can help surgeons to identify the position of the lingual and the mandibular foramen, thus preventing inferior alveolar nerve injury., (Copyright © 2013 European Association for Cranio-Maxillo-Facial Surgery. Published by Elsevier Ltd. All rights reserved.)

Purpose: To compare the peri-implant bone loss of mandibular complete-arch implant-supported fixed prostheses (FPSs) supported by three and four implants and to correlate with the size of the horizontal and vertical distal cantilever at prosthesis placement (T1) and after 1 year (T2). Materials and Methods: A total of 72 external hexagon (EH) type implants were placed in 20 participants. Of these, 24 supported an FPS with three implants (G3I) and 48 with four implants (G4I). The mandibular implants were named 1, 2, 3, and 4 according to their location in the arch, in a clockwise direction. Digital periapical radiographs were taken at times T1 and T2 for analysis and measurement of peri-implant bone loss. The horizontal and vertical distal cantilevers were measured with a digital caliper and correlated with peri-implant bone loss. Results: The survival rate of implants in G3I was 91.66%, and in G4I it was 97.91%. The mean bone loss in G3I was 0.88 ± 0.89 mm, and in G4I it was 0.58 ± 0.78 mm (P = .225). There was no correlation between distal horizontal cantilevers and bone loss in the studied groups, with G3I being -0.25 (P = .197) and G4I -0.22 (P = .129). Larger vertical cantilevers of implants 1 (P = .018), 3 (P =.015), and 4 (P = .045) correlated with greater bone loss in G4I. Conclusions: The number of implants in an FPS did not influence peri-implant bone loss after 1 year of follow-up. Larger vertical cantilevers influenced greater bone loss in complete-arch implant-supported fixed prostheses supported by four implants. [ABSTRACT FROM AUTHOR]

The aim of this study was to evaluate healing at the donor site following autogenous block graft harvesting from the mandibular ramus. In this retrospective study, cone beam computed tomography images taken at different time-points were examined, and the volumes of preoperative and postoperative regions of interest were calculated in the software. Images were classified into four groups: 0–3 months, 4–6 months, 7–12 months, and >12 months post-surgery. To characterize the healing process over time, statistical analyses were conducted for both the 70% and 80% healing thresholds. Nearly half (n = 15, 47%) of the 32 patients included in this study achieved 70% bone healing within 4–12 months post-surgery. At the end of the 28-month period covered by this study, 21 patients (66%) had achieved 70% bone healing. The median time to achieve 70% healing was 9 months, while the median time to achieve 80% healing was 28 months. The findings of this study validate the feasibility of reutilizing the mandibular ramus area for additional bone augmentation when other intraoral sites are unavailable. [ABSTRACT FROM AUTHOR]

Background: Relapses following orthognathic surgery have been reported to exceed 2% to 50%, depending on multiple factors. This study aimed to analyze the stability after orthognathic surgery in patients with mandibular ramus height asymmetry through 3D reconstruction using Cone-beam CT. Methods: This retrospective cohort study investigated patients who underwent mandibular setback surgery using bilateral sagittal split ramus osteotomy. Three-dimensional CT scans were taken at three different time points. Evaluation of the postoperative stability involved measuring changes in the x, y, and z axes as well as roll and yaw rotations of the mandible at specific landmarks (B point, mental foramen) on 3D CT scans obtained immediately after surgery and 6–12 months postoperatively. They were categorized into four groups based on bilateral mandibular height asymmetry through Asymmetry index (AI). The one-way ANOVA was implemented to compare the intergroup differences and Tukey's post hoc test was employed. Additionally, the Pearson correlation coefficient was also calculated. Results: A total of 24 patients were included in this study. The corresponding AI, representing the degree of asymmetry in both mandibles, were calculated as Group 1 was 1.25 ± 0.64%, Group 2 was 2.89 ± 0.47%, Group 3 was 5.03 ± 0.51%, and Group 4 was 9.40 ± 1.99%. The x-axis change in Group 4 was significantly larger at 1.71 mm compared to Group 1 at 0.64 mm. The mandibular roll, Group 4 showed a statistically significant increase at 1.33° compared to Group 1 at 0.35°. And there was a significant positive correlation observed between x-axis change and AI (p = 0.019), as well as between mandibular roll and AI (p = 0.025). Conclusion: After orthognathic surgery, stability was influenced by numerous factors, with the findings of this study suggesting that the degree of ramus height asymmetry in the mandible can be considered one contributing factor. [ABSTRACT FROM AUTHOR]

Objective: To apply the more accurate technique for mandibular superimposition and provide a valuable reference for the assessment of mandibular tooth movement and condylar remodeling before and after orthodontic treatment. Methods: This retrospective study involved 38 adult patients who underwent two cone beam computer tomography (CBCT) scans at different stages of treatment at Fujian Provincial People’s Hospital between September, 2020 and December, 2022. The software Dolphin was used for mandible segmentation, enabling voxel‐based mandibular superimposition with the mandibular ramus as the reference region. The Geomagic Wrap software was employed to process surface‐based mandibular superimposition with the mandibular ramus as a reference. Additionally, the voxel and surface‐based methods were compared for precision, with the mandibular ramus being the reference. Results: After voxel‐based mandibular superimposition using the mandibular ramus as a reference, with all measurement errors (< 0.20 mm). In contrast, the results of surface‐based mandibular superimposition with the same reference, and the measurement errors were all less than 0.10 mm. The Wilcoxon signed‐rank test revealed statistically significant differences between AS1 and BS1, AS2 and BS2, AS3 and BS3, and AS4 and BS4 (all r< 0.05). Moreover, the absolute mean distances of AS1-AS4 were all greater than those of BS1-BS4. Conclusion: All mandibular superimposition procedures, including the voxel‐ and surface‐based ones using the mandibular ramus as a reference, have acceptable surface errors (< 0.20 mm), indicating the good reliability of these techniques. Under the specified conditions, surface‐based mandibular superimposition appears to yield a higher degree of precision compared with the voxel‐based technique. [ABSTRACT FROM AUTHOR]

Background: The mandible, being a robust bone, remains intact postmortem and can be utilized for gender determination. Morphometric analysis of the mandibular ramus holds significance for anthropologists, anatomists, and prosthetists. This study aims to assess the height and breadth of the mandibular ramus and their association with gender. Materials and Methods: The study was conducted on 56 cadaveric mandibles (18 female and 38 male). The height and breadth of the mandibular ramus were measured.Results: The mean ± SD for ramus height and breadth on the right side for females was 41.18 ± 4.70 mm and 28.89 ± 2.28 mm, respectively, while on the left side, it was 43.03 ± 3.57 mm and 30.70 ± 7.62 mm, respectively. For males, the mean ± SD for ramus height and breadth on the right side was 47.34 ± 2.88 mm and 33.14 ± 3.26 mm, respectively, while on the left side, it was 47.39 ± 3.88 mm and 32.39 ± 3.85 mm, respectively. Conclusion: The mean ± SD for ramus height and breadth was greater in males than in females. Although this study was conducted on cadaveric mandibles, the mandibular ramus can be utilized for gender determination in medico-legal and forensic cases.Keywords: gender, mandible, morphometry, mandibular ramus

Background: The goal of treating broken mandibular condyles is to return the affected jaw to its pre-trauma state in terms of masticatory ability, occlusion, symmetry, and function. The two methods can be used to treat the mandibular condylar fracture. These protocols consist of two types: the closed therapy, which employs closed reduction to immobilise the fracture segments, and the open treatment, which involves open reduction of the fracture segments by surgery, followed by internal fixation. Aim: to compare the post-treatment results of closed therapy versus open surgical treatment for mandibular condyle fractures. Methods: 42 individuals were treated with either open reduction with internal fixation or closed reduction utilising IMF in 2 groups (n = 12). The clinical parameters of lateral excursion and protrusion, occlusion, mandibular ramus height, deviation/deflection during jaw opening, and pain evaluation using VAS were measured at 1stand 3rd day and at 1, 3, and 6 weeks. The gathered data were examined statistically. Results: For Group I and Group II, the inter-incisal opening was 8.125±0.3467mm and 6.016±.1528mm, respectively. These values were statistically significant (p ~0.00001). In the surgical groups, it climbed to 17.433±0.3822mm at 3 months and 19.175±0.3696mm at 6 weeks post-operatively. The interincisal opening for the non-surgical group was smaller during the first postoperative week, and subsequently it grew to 9.375±0.2734mm and 12.208±0.1881mm, respectively, at the third and sixth months. Both of these results have statistical significance (p ~<0.00001). At 1, 3, and 6 months recall, the protrusive movement increased in Group I, with means of 0.4667±0.403, 2.275±0.2006mm, and 2.7917±0.0289 mm, respectively. Conclusion: The current study concludes that, in terms of inter-incisal opening, lateral excursion and protrusive mandibular movement range, pain parameters, facial symmetry, occlusion, and ramal height restoration in a 6-week follow-up period, surgical open reduction and internal fixation treatment of the mandibular condylar fracture is superior to non-surgical closed reduction. [ABSTRACT FROM AUTHOR]

Purpose: To assess the presence of mandibular canal bifurcation (BMC) and classify these variations by correlating findings with sex, age and facial skeletal pattern, measurements were made, including height, width, and distance from bifurcation to anatomical cortical bones. Methods: BMC was identified in cone beam CT exams of 301 patients and classified according to its origin, location, direction, configuration and ending. The height and width of the MC before and after the bifurcation; height and width of the BMC; and distance from BMC to alveolar (C1), buccal (C2), lingual (C3) and basal (C4) bone cortices were measured. All data were correlated with sex, age, and facial skeletal pattern (class I, II, III). The significance level was 5%. Results: 67 BMC (22.26%) were identified in 55 patients (18.28%). Bifurcations were more prevalent in females (p = 0.57), aged 18–39 years (p = 0.40), class I (p = 0.77). Single bifurcations, located in the posterior region of the mandible, originating in the MC, with a superior direction and ending in the retromolar foramen were more prevalent (p > 0.05). Mean cortical measurements were higher in male individuals, with significant differences only at C1 (p = 0.03). The mean height and width of BMC were 2.24 (± 0.62) and 1.75 (± 0.45) mm. There was no association between BMC classification and the variables studied (p > 0.05). Conclusion: Approximately 1/5 of the population studied had BMC. There were no associations of BMC presence or characteristics with sex, age, and facial skeletal pattern. The distance from bifurcation to alveolar (superior) cortical bone is greater in male individuals. [ABSTRACT FROM AUTHOR]

Primate mandibular morphology is often associated with jaw functionality of the masticatory complex in the context of variation in diets. Recent research into the disparities between the diet and jaw functionality in male and female hominoids is inconclusive and suggests that sexual dimorphism in the mandible may be influenced by external factors such as temporalis and masseter muscle morphology, which in turn may be influenced by sexual selection. As the muscles associated with mastication (i.e., the type of chewing exhibited by primates and other mammals) encompass the mandible as well as the neurocranium, including the sagittal crest among some individuals, this study investigates sex‐specific associations between regions of the mandibular ramus and neurocranium associated with mastication in a dentally mature sample of Gorilla and Pongo. A total of four cranial and mandibular variables were measured in two Gorilla taxa (Gorilla gorilla gorilla and Gorilla beringei graueri) and one Pongo taxon (Pongo pygmaeus pygmaeus) (n = 220). For all three taxa, we investigate (a) whether the degree of sexual dimorphism in cranial regions associated with sagittal cresting (sagittal crest size (SCS) and temporalis muscle attachment area (TMAA)) is proportional to the degree of mandibular ramus area (MRA) and coronoid process height (CPH) sexual dimorphism, (b) whether there are sex differences in scaling relationships between TMAA and MRA, and (c) whether there are sex differences in the strength of association between TMAA and CPH. We show that for G. g. gorilla, variables associated with sagittal cresting show higher sexual dimorphism values than our two mandibular ramus variables, which is not the case for G. b. graueri or for P. p. pygmaeus. All three taxa show similar sex‐specific scaling relationships between TMAA and MRA, where for males this relationship does not diverge from isometry, and for females there is a negative allometric relationship. Our findings also show intraspecific sex differences in allometric slopes between MRA and TMAA for all three taxa. Only G. g. gorilla shows a significant association between TMAA and CPH, which is observed in both sexes. Although there are some statistical associations between the cranial and mandibular regions associated with mastication, our results show that among male gorillas and orangutans, patterns of variation in the sagittal crest, TMAA, mandibular ramus and the coronoid process cannot be explained by the muscle attachment hypothesis alone. These findings have implications surrounding the associations between social behaviour and the morphology of the craniofacial complex. [ABSTRACT FROM AUTHOR]

Background: The condylar process of mandible is an ellipsoid hard tissue (bony structure) with a thin neckline that joins to the mandibular ramus. The condylar processes are a critical anatomic component of the mandible that development of mandibular bone is attributed in the sagittal and vertical directions by condylar process. Objective: To radiographical assessment of condylar head measurements according to gender and site by uses cone beam computed tomography. Patients and Methods: The study samples consisted of sixty-five individuals (19 male and 46 female) with age range from (20-50) years old. Width of condylar head, length of condylar head and condylar head height were measured in the study by using cone beam computed tomography from radiology archive in specialist dental center in Diyala. Results: The results show condylar head width, condylar head height and condylar head length in sides (right and left), males have noted higher mean value than females. The results show condylar head width and condylar head length in left side, have recorded higher mean value than right side. While, condylar head height in left side, have recorded lower mean value than right side. Conclusion: Condylar dimensions and sizes may be associated with gender and site. Males have higher condylar dimensions and sizes than females. [ABSTRACT FROM AUTHOR]

In studies of mammalian mastication, a possible relationship has been proposed between bilateral recruitment of jaw adductor muscle force during unilateral chewing and the degree of fusion of the mandibular symphysis. Specifically, species that have unfused, mobile mandibular symphyses tend to utilize lower levels of jaw adductor force on the balancing (nonchewing) than the working (chewing) side of the head, when compared to related species with fused symphyses. Here, we compare jaw adductor recruitment levels in two species of musteloid carnivoran: the carnivorous ferret (unfused symphysis), and the frugivorous kinkajou (fused symphysis). During forceful chewing, we observe that ferrets recruit far more working‐side muscle force than kinkajous, regardless of food toughness and that high working‐to‐balancing side ratios are the result of increased working‐side force, often coupled with reduced balancing‐side force. We propose that in carnivorans, high working‐to‐balancing side force ratios coupled with an unfused mandibular symphysis are necessary to rotate the hemimandible for precise unilateral occlusion of the carnassial teeth and to sustain laterally oriented force on the jaw to engage the carnassial teeth during shearing of tough foods. In contrast, the kinkajou's flattened cheekteeth permit less precise occlusion and require medially‐oriented forces for grinding, thus, a fused symphysis is mechanically beneficial. Research Highlights: Ferrets' (unfused mandibular symphyses) use of asymmetrical jaw muscle activity may optimi forces for carnassial shearing. Kinkajous' more nearly equal force may be facilitated by their fused symphysis and flat cheek teeth. [ABSTRACT FROM AUTHOR]

The aim of this study was to introduce a novel intraoral technique for performing mandibular nerve blocks in dromedary camels (Camelus dromedarius). In this study, 18 adult camel skulls of varying ages and breeds were examined to determine the position of the mandibular foramen. Using a Vernier caliper, three dimensions in millimeters were measured: (1) the distance between the mandibular foramen (MF) and the caudal edge of the third molar tooth at the occlusal surface level, (2) the distance between the MF and the rostral edge border of the mandible's ramus (RER) at the occlusal surface level, and (3) the distance between the MF and the ventral margin border of the mandible (VM). The technique was evaluated using five intact camel cadaver heads (n = 5), and a total of ten mandibular nerve blocks were described. An 18-gauge 80-mm Tuohy needle was inserted into the mouth commissure and advanced caudally while injecting a saline-methylene blue solution. The accuracy of the injection was confirmed through the infiltration of the contrast dye into the target area using computed tomography (CT) and post procedural dissection. Anatomical study of the mandibular nerve site was performed to aid the blind insertion of the needle. The findings contribute to the development of veterinary anesthesia techniques and provide anatomical considerations for clinicians performing oral surgeries in sedated camels. The results demonstrated the successful implementation of the intraoral technique, highlighting its efficacy and reliability in achieving local anesthesia for oral surgeries involving the lower jaw and teeth in sedated camels. Further research studies are needed to evaluate the long-term efficacy and safety of the technique and to compare it with existing approaches. [ABSTRACT FROM AUTHOR]

Objective: The purpose of this study is to investigate the type of ridge (degree of angulation of the lingual concavity) and the buccolingual dimensions in the area of the first and second molars in both genders of different ages and how this will affect implant placement in the posterior mandible. Materials and Methods: This retrospective cross‐sectional study comprised cone beam computed tomography images of 150 dental patients (75 males and 71 aged ≥30). The following were measured/reported: type (morphology) of the ridge (convex [C], parallel [P], or undercut [U]), buccolingual width at the base and the crest of the ridge, and ridge height. The concavity angle, depth, and length of the U‐shaped ridge were measured too. Results: The prevalence of type U ridge ranged from 32.7% in the first molar region to 62.7% in the second molar region. Almost all measurements and ridge type distributions were comparable amongst the age groups (p >.05). Very few significant differences were found when comparing #36 versus #37 and #46 versus #47 teeth, with no differences in the distribution of the ridge types (p >.05). Quite the inverse, all measurements were statistically different when comparing #36 versus #37 and #46 versus #47 teeth, and type U ridge was more frequent in second molar compared to the first molar regions, respectively (p <.05). Many measurements were statistically higher in females; the inverse was true for a few measurements (p <.05). Type U ridge in #36 and #37 was found more frequently among males (p <.001). In contrast, the ridge types in #37 and #47 were not statistically different gender‐wise. Conclusions: The U type of ridge was more prevalent in the investigated population, encountered more frequently in the second molars generally and in the first molars of males than females. Most posterior mandibular measurements are similar age‐ and side‐wise but seem different gender‐ and tooth‐wise. [ABSTRACT FROM AUTHOR]

The aim of this study is to determine whether or not the breed and sex factors have an effect on the shape in the mandibles of Hamdani and Awassi sheep. A total of 31 mandibles were used. The samples were analyzed via geometric morphometric methods by using semilandmark. In the study, it was determined that the first principal component accounted for 36.52% of the total shape difference. According to principal component analysis, samples were clustered significantly in terms of breed; whereas, they were not clustered in terms of sex. In terms of the first principal component, the places where the shape differences were concentrated were the attachment sites of teeth to the mandible, between the second molar and ramus mandibulae, the processus coronoideus and the angulus mandibulae. The Mandibulae of Hamdani sheep had a higher body than the mandible of Awassi sheep. The mandibulae of male sheep was more voluminous than the mandible of female sheep, especially in the body area. Consequently, it is thought that the data obtained as a result of the study would serve as a reference for the ruminant mandible remains obtained from archaeological excavations. [ABSTRACT FROM AUTHOR]

Background: Mental foramen is a small foramen situated in anterolateral aspect of the body of the mandible. Normally, mental foramen is located below the interval between the premolars. It transmits mental nerve, artery and vein. Mental nerve is a branch of inferior alveolar nerve which supplies sensation to lower lip and the labial mucosa and lower canines and premolars. The most useful injection for anaesthetising the mandibular teeth is the inferior alveolar nerve block. Any foramen in addition to mental foramen in the body of the mandible is known as accessory mental foramen. Accessory mental foramen transmits the accessory branch of mental nerve. Materials and methods: The mandibles which were used for our study were procured from the Department of Anatomy, Siddhartha Medical College (Govt), Vijayawada over a period of 6 years. About 70 adult dry South Indian mandibles, irrespective of age and sex, with either all the teeth intact or with preserved alveolar margins, were used for our study. The bones with gross pathological deformities were excluded from our study. The number, shape and the orientation of the MF were determined by a visual examination. The shape of mental foramen in dry human adults was analyzed by visual examination of the both sides of the mandible. Result: The present study showed that the position of mental foramen from symphysis menti and posterior border of ramus of mandible was more on right side than left side and found to be insignificant while position of mental foramen from inferior border of body of mandible was more on left side than right side and found to be insignificant for right side while significant for left side. The shape of mental foramen on right side was found to be Oval shape - 65.7% and round shape - 34.3% while on left side Oval shape-71.4% and round shape - 28.6%. Conclusion: Hence, mental foramen plays a pivotal role in performing major facial surgeries and is an important landmark for several facial procedures performed. [ABSTRACT FROM AUTHOR]

Multiple myeloma (MM) is a plasma cell malignancy, and its typical radiographic presentation includes punched-out radiolucency of the skull. It is a bourgeois description of myeloma and often holds good in most cases. However, the diagnosis can get tricky when a patient walks into the clinic with non-specific signs and symptoms. Many suspicions arise when we examine a well-defined mandibular swelling, but the real picture is revealed with thorough screening. This article presents a rare mandibular swelling diagnosed as MM, emphasizing important differential diagnoses for maxillofacial surgeons and pathologists. [ABSTRACT FROM AUTHOR]

Introduction: The mandible is the largest and strongest bone in the facial skeleton, with the lingula and coronoid process serving as important landmarks for surgical procedures. Objective: The study's objective was to have significant ramifications for oral and faciomaxillary surgical procedures. Understanding the morphology of the lingula and coronoid process can help in bone grafting, reconstructive surgery, and other surgical procedures. Materials And Methods: : A total of 63 dried adult human mandibles from the GMC Srinagar department of anatomy were examined in this observational study. Manual vernier calipers were used to record morphological parameters of the lingula and coronoid process, and morphometric measurements were taken in relation to several mandibular characteristics. Results: The most common lingula morphology was triangular (50.79%), followed by nodular (21.42%), truncated (15.87%), and assimilated (11.9%). The average height of the lingula was 7.48 +/- 139 mm, with an average distance of 16.33 mm from the anterior border of the ramus and 15.31 mm from the posterior border. The most common coronoid process shapes were triangular, hook-shaped, and rounded, with mean heights of 18.44+1.99mm and 18.99+1.44 mm on the right and left sides, respectively Conclusion: The findings of this study have important implications for faciomaxillary and oral surgical procedures. The morphological knowledge of the lingula and coronoid process can aid in reconstructive purposes, bone grafting, and other surgical interventions. [ABSTRACT FROM AUTHOR]

Three-dimensional finite element models (FEMs) are powerful tools for studying the mechanical behaviour of the feeding system. Using validated, static FEMs we have previously shown that in rhesus macaques the largest food-related differences in strain magnitudes during unilateral postcanine chewing extend from the lingual symphysis to the endocondylar ridge of the balancing-side ramus. However, static FEMs only model a single time point during the gape cycle and probably do not fully capture the mechanical behaviour of the jaw during mastication. Bone strain patterns and moments applied to the mandible are known to vary during the gape cycle owing to variation in the activation peaks of the jaw-elevator muscles, suggesting that dynamic models are superior to static ones in studying feeding biomechanics. To test this hypothesis, we built dynamic FEMs of a complete gape cycle using muscle force data from in vivo experiments to elucidate the impact of relative timing of muscle force on mandible biomechanics. Results show that loading and strain regimes vary across the chewing cycle in subtly different ways for different foods, something which was not apparent in static FEMs. These results indicate that dynamic three-dimensional FEMs are more informative than static three-dimensional FEMs in capturing the mechanical behaviour of the jaw during feeding by reflecting the asymmetry in jaw-adductor muscle activations during a gape cycle. This article is part of the theme issue 'Food processing and nutritional assimilation in animals'. [ABSTRACT FROM AUTHOR]

Purpose: This study assessed the diagnostic performance of stitched and non-stitched cross-sectional cone-beam computed tomography (CBCT) images of non-displaced ovine mandibular fractures. Materials and Methods: In this ex vivo study, non-displaced fractures were artificially created in 10 ovine mandibles (20 hemi-mandibles) using a hammer. The control group comprised 8 hemi-mandibles. The non-displaced fracture lines were oblique or vertical, <0.5 mm wide, 10-20 mm long, and only in the buccal or lingual cortex. Fracture lines in the ramus and posterior mandible were created to be at the interface or borders of the 2 stitched images. CBCT images were obtained from the specimens with an 80 mm×80 mm field of view before and after fracture induction. OnDemand software (Cybermed, Seoul, Korea) was used for stitching the CBCT images. Four observers evaluated 56 (28 stitched and 28 non-stitched) images to detect fracture lines. The diagnostic performance of stitched and non-stitched images was assessed by calculating the area under the receiver operating characteristic curve (AUC). Sensitivity and specificity values were also calculated (alpha=0.05). Results: The AUC was calculated to be 0.862 and 0.825 for the stitched and non-stitched images, respectively (P=0.747). The sensitivity and specificity were 90% and 75% for the non-stitched images and 85% and 87% for the stitched images, respectively. The inter-observer reliability was shown by a Fleiss kappa coefficient of 0.79, indicating good agreement. Conclusion: No significant difference was found in the diagnostic performance of stitched and non-stitched crosssectional CBCT images of non-displaced fractures of the ovine mandible. [ABSTRACT FROM AUTHOR]

The anatomical characteristics and the cortico-cancellous nature of bone disrupted by the presence of teeth make the mandible more vulnerable to fractures during traumatic injuries of the face. Fractures of the angle region constitute about 30% of mandibular fractures due to the change in dentate bone to the lateral flare of ramus, change in grain pattern of the bone, and presence of third molars all weakening the region making it fragile and thus fracture. Several studies corroborated the effectiveness of Champy's technique as to have the lowest complication rate when compared to the other techniques. Though a well-sequenced procedure, fixing an angle fracture is practically challenging and here we describe our experience, with a modification of the sequence to aid in better surgical outcome. [ABSTRACT FROM AUTHOR]

Purpose: This study evaluated the long-term survival and success rates of dental implants placed with autogenous onlay block bone grafts harvested from the mandibular ramus. Materials and Methods: Patients treated with onlay bone graft from the mandibular ramus due to a severe vertical alveolar defect from 2001 to 2017 were included in this study. The marginal bone loss, success, and survival time of the implants were recorded and analyzed with clinical factors, such as time from bone graft to implant placement, type of implant prosthesis connection, history of periodontitis, and insertion depth. Results: Seventy-five implants in 40 onlay bone-grafted areas of 38 patients were included, with a mean follow-up period of 102 months (range: 14 to 192 months). Two grafts were removed before implant placement. Of the 75 implants, 11 implants were lost. History of periodontitis and marginal bone loss at 6 months after implant placement were significantly associated with implant success. The receiver operating characteristic curve showed that a marginal bone loss of 0.75 mm after 6 months of implant placement was related to implant success, with a sensitivity of 72.2% and specificity of 89.6%. Conclusion: Implants placed with onlay bone graft from ramal bone had more frequent biologic complications, and failures may be predicted by measuring the amount of implant bone loss after 6 months of placement. [ABSTRACT FROM AUTHOR]

Vertical ridge augmentation is a demanding and technique-sensitive surgical procedure. In the present case series, cone beam CT (CBCT) scans from the clinical routine of patients treated using a novel approach for vertical bone augmentation were assessed. All patients showed a single-tooth class 5 defect and were treated using a modification of the original shell technique. Cortical bone plates were replaced with a lamina composed of a partially demineralized porcine xenograft. CBCT scans of six consecutive patients were treated with the lamina and particulate bone from the mandibular ramus prior to a single tooth implant in the anterior maxilla were included. Pre- and postsurgical CBCT data sets were superimposed and analyzed digitally using surface matching and Boolean subtraction. The volume of the grafted area was calculated with and without the xenograft. The vertical gain of the ridge height measured in this case series varied from 7 to 11.3 mm. The mean vertical gain was 8.97 mm. The mean volume including the xenograft was 382.59 mm3 (SD 73.39) and 250.84 mm3 (SD 53.67) without the lamina. The modified shell technique used in this case series for the vertical augmentation of single-tooth class 5 defects provided sufficient bone for single implant restorations. [ABSTRACT FROM AUTHOR]

Sex identification of a deceased human individual by means of the mandible is very important for forensic dentistry. The aim of the present study was to determine the sex of Chilean individuals by mandible analysis in panoramic radiographies. Linear and angular parameters of the mandible were analyzed from panoramic radiographies (PR). The study included PR of adult Chilean individuals, of both sexes, with optimum solution and contrast, and which allowed the angles and rami of the mandible to be viewed. Sex was determined by univariate and bivariate discriminant function analysis. The sample consisted of 594 PR of individuals aged between 18 and 84 years. The best sex predictor using univariate discriminant function analysis was the mandibular ramus height (MRH) (74.1 %), followed by the distance from the mental foramen - mandibular base (DMF-MB) (69.1 %) and the bicondylar breadth (BC) (66.7 %). The parameters that presented the lowest sex prediction were the angle of the mandible (AM) with 55.0 % and the distance between mental foramina (DMF) with 53.7 %. The best sex prediction was obtained by the step model of discriminant function analysis (80.2 %), including only three parameters: MRH, BC and DMF-MB. The parameters height of the mandibular ramus, bicondylar breadth and distance from the mental foramen - base of the mandible are good predictors of sex in Chilean individuals when used in conjunction; they are therefore indicated for sex determination in the contemporary Chilean population. [ABSTRACT FROM AUTHOR]

Background: The human mandible is a complex bone that plays a critical role in various functional and aesthetic aspects of human anatomy. The morphologic and morphometric parameters of the mandible are essential for understanding the variations in the mandible among different populations. Objective: This study aimed to evaluate the morphologic and morphometric parameters of the human mandible. Methods: Fifty mandibles obtained from cadavers of different ages and genders were measured for morphologic features such as shape, size, and position of the mandible, as well as anatomical landmarks such as the angle of the mandible, ramus height, and body length. The data obtained were statistically analyzed using SPSS software, and the results were compared with previous studies in the literature. Results: The mandible was generally symmetrical in shape, and the size of the mandible increased with age. The angle of the mandible was wider in males than females, and the ramus height was higher in males than females. The body length of the mandible was also longer in males than females. Conclusion: This study provides valuable information about the morphologic and morphometric parameters of the human mandible. The results can be used in various fields such as forensic science, orthodontics, and maxillofacial surgery. The knowledge of these parameters can also aid in understanding the variations in the mandible among different populations. Further studies are needed to explore the ethnic and regional differences in the morphologic and morphometric parameters of the mandible. [ABSTRACT FROM AUTHOR]

This article from the Romanian Journal of Oral Rehabilitation discusses the diagnosis and treatment planning of mandibular laterognathism, a condition characterized by misalignments in the jaw. The study focuses on using virtual planning technology for an interdisciplinary approach to manage mandibular prognathism, a specific dental irregularity. The researchers were able to restore interocclusal relationships, achieve facial symmetry, and improve the aesthetic and functional appearance of patients with severe facial asymmetry. The article also emphasizes the importance of an interdisciplinary approach involving orthodontic treatment and orthognathic surgery for adult patients with class III malocclusion. [Extracted from the article]

Alveolar ridge augmentation of atrophic posterior mandibular ridge represents a challenge in oral and maxillofacial surgery to restore aesthetic and function. The aim of the study was to compare the clinical and radiographic outcomes of bone formation in atrophic posterior mandibles augmented using onlay symphysis cortico-cancellous bone block with that augmented using sandwich bone augmentation technique (Inlay). Twelve patients were selected with missing mandibular posterior teeth. CBCT were done for all patients preoperatively to assess the residual bone height, ranged between 5 and 7 mm from the inferior alveolar nerve with adequate sufficient alveolar ridge width more than 4 mm. Patients required bone augmentation procedure with autologous onlay chin graft (group I) versus those used as inlay sandwich technique (group II). Clinical and radiographic analysis were done to analyses the newly formed bone and bone height. Percent of change in bone height was also calculated and revealed that group I was higher than group II, however, statistically insignificant differences between the two groups were found regarding the percentage of newly formed bone. Vertical ridge augmentation procedures using onlay chin graft took lesser time than the interpositional grafting with fixation technique, however, both techniques are promising for vertical ridge augmentation. [ABSTRACT FROM AUTHOR]

The aim of this study was to evaluate the bone healing of tight‐fit implants placed in the maxilla and mandible of subjects compromised with metabolic syndrome (MS) and type‐2 Diabetes Mellitus (T2DM). Eighteen Göttingen minipigs were randomly distributed into three groups: (i) control (normal diet), (ii) MS (cafeteria diet for obesity induction), (iii) T2DM (cafeteria diet for obesity induction + Streptozotocin for T2DM induction). Maxillary and mandibular premolars and molar were extracted. After 8 weeks of healing, implants with progressive small buttress threads were placed, and allowed to integrate for 6 weeks after which the implant/bone blocks were retrieved for histological processing. Qualitative and quantitative histomorphometric analyses (percentage of bone‐to‐implant contact, %BIC, and bone area fraction occupancy within implant threads, %BAFO) were performed. The bone healing process around the implant occurred predominantly through interfacial remodeling with subsequent bone apposition. Data as a function of systemic condition yielded significantly higher %BIC and %BAFO values for healthy and MS relative to T2DM. Data as a function of maxilla and mandible did not yield significant differences for either %BIC and %BAFO. When considering both factors, healthy and MS subjects had %BIC and %BAFO trend towards higher values in the mandible relative to maxilla, whereas T2DM yielded higher %BIC and %BAFO in the maxilla relative to mandible. All systemic conditions presented comparable levels of %BIC and %BAFO in the maxilla; healthy and MS presented significantly higher %BIC and %BAFO relative to T2DM in the mandible. T2DM presented lower amounts of bone formation around implants relative to MS and healthy. Implants placed in the maxilla and in the mandible showed comparable amounts of bone in proximity to implants. [ABSTRACT FROM AUTHOR]

Background: Mandibular flexion (MF) is a complex biomechanical phenomenon, which involves a deformation of the mandible, due mainly to the contraction of the masticatory muscles, and it can have numerous clinical effects. The deformation of the lower jaw caused by mandibular flexion is generally very small, and it is often overlooked and considered irrelevant from a clinical point of view by many authors; however, it should be important to remember that median mandibular flexure (MMF) has a multifactorial aetiology. The main aim of the current systematic review is to highlight the different factors that can increase MF in order to help clinicians identify patients to whom they should pay more attention. As a secondary outcome, we wanted to analyse the preventive measures and suitable techniques to be adopted to minimise the negative effects of this phenomenon on oral fixed rehabilitations. Methods: The review, which was carried out in accordance with the "Preferred Reporting Items for Systematic reviews and Meta-Analyses" (PRISMA) flowchart, was recorded in the "International Prospective Register of Systematic Reviews" (PROSPERO). As research questions, "Patient/Population, Intervention, Comparison and Outcomes" (PICO) questions were employed. Using the ROBINS-I technique, the risk of bias in non-randomised clinical studies was evaluated. Results: The initial electronic search identified over 1300 potential articles, of which 54 studies were included in this systematic review. Information regarding the relationship between MF and individual factors, mandibular movements, impression taking, and fixed rehabilitations were obtained. Conclusions: The studies included in this systematic review showed that MF is greater during protrusive movements, in the posterior areas of the lower jaw, and in patients with brachial facial type, greater jaw length; small gonial angle; and less density, length, and bone surface of the symphysis. The biomechanical effects of mandibular flexion on fixed restorations are debated. Prospective clinical and radiological observational studies should be conducted to evaluate the potential short-, medium-, and long-term consequences of MF. [ABSTRACT FROM AUTHOR]

Neurofibromatosis is an autosomal dominant neurocutaneous syndrome characterized by skin lesions and central or peripheral nervous system tumors. Although neurofibromatosis is a neurocutaneous disease, it also involves multiple systems. For example, bone lesions have been reported in 40% of patients. As in this case, pathologies associated with the mandible and temporomandibular joint in neurofibromatosis are rarely reported in the literature. In our case, we aimed to emphasize that skeletal malformations may also be present in the rich clinical picture of neurofibromatosis. Maxillofacial computed tomography of a 24-year-old female patient who was followed up at Selçuk University Hospital with a diagnosis of neurofibromatosis revealed an appearance compatible with atrophy in the right half of the mandible. The mandibular ramus was 41.27 mm on the right and 53.44 mm on the left; the diameter of the condyloid process was 10.31 mm on the right and 15.71 mm on the left. The joint distance was increased on the right. Radiologic examinations in neurofibromatosis syndrome should be performed considering the possibility of bone lesions. These examinations are especially important for the prevention of pathologic fractures in bones. [ABSTRACT FROM AUTHOR]

Background/Aim. A lingual foramen (LF) is a small opening on the lingual surface of the mandible, most frequently located in the middle of the anterior part of the mandible, and shows significant variations in its location, size, and number. The aim of this study was to assess the location and anatomical characteristics of LF using cone beam computed tomography (CBCT). Methods. The research was designed as a retrospective study in which 99 CBCT scans were analyzed. The analysis covered the number of LF, their location concerning the teeth and the mandibular region itself, diameter, distance from the alveolar ridge crest, distance from the inferior border of the mandible, distance from the tooth apex, and position in relation to the tooth apex. Results. The average frequency of LF per patient was 2.4 ± 1.2. The largest number of LF were localized in the region of lower central incisors. Out of the total number of LF, 82.5% belonged to median LF, while 17.5% belonged to lateral LF. In 63.2% of cases, LF had a diameter of ≤ 1 mm, whereas, in 98.3% of cases, it was localized below the tooth apex. There was a statistically significant difference in the distance of LF from the alveolar ridge crest and the LF diameter in relation to gender (p = 0.019; p = 0.008). Conclusion. LF can be reliably localized and visualized using CBCT. It is recommended that CBCT scanning of the mandible be used while planning an oral surgical procedure and implant placement in order to prevent injuries of the neurovascular bundle, which passes through LF. [ABSTRACT FROM AUTHOR]

Objectives: Antidepressants, specifically Selective Serotonin Re‐uptake Inhibitors (SSRIs), that alter serotonin metabolism are currently the most commonly prescribed drugs for the treatment of depression. There is some evidence to suggest these drugs contribute to birth defects. As jaw development is often altered in craniofacial birth defects, the purpose of this study was to interrogate the effects of in utero SSRI exposure in a preclinical model of mandible development. Materials and Methods: Wild‐type C57BL6 mice were used to produce litters that were exposed in utero to an SSRI, Citalopram (500 μg/day). Murine mandibles from P15 pups were analysed for a change in shape and composition. Results: Analysis indicated an overall shape change with total mandibular length and ramus height being shorter in exposed pups as compared to controls. Histomorphometric analysis revealed that first molar length was longer in exposed pups while third molar length was shorter in exposed as compared to control. Histological investigation of molars and surrounding periodontium revealed no change in collagen content of the molar in exposed pups, some alteration in collagen composition in the periodontium, increased alkaline phosphatase in molars and periodontium and decreased mesenchymal cell marker presence in exposed mandibles. Conclusion: The results of this study reveal SSRI exposure may interrupt mandible growth as well as overall dental maturation in a model of development giving insight into the expectation that children exposed to SSRIs may require orthodontic intervention. [ABSTRACT FROM AUTHOR]

The purpose of this study was to evaluate the current evidence on marginal bone-level changes (ΔMBL) around internal connection implants with fixed prostheses by jaw location over time. An electronic literature search for ΔMBL (change in marginal bone level) was conducted in 6 databases. The data from the included manuscripts were categorized by jaw sextant of the implants and duration of follow-up (< 2 years, 2–5 years, and >5 years). Meta-analyses were performed on groups with at least 5 studies. A total of 1270 records were screened. Full-text review of 413 papers resulted in a total of 46 studies (representing 2259 patients with 4970 implants) included for quantitative synthesis and analysis. The ΔMBL was summarized at 2 time intervals with the following results: < 2 years (anterior maxilla = 0.393 mm [95% confidence interval {CI}, 0.172, 0.613], posterior maxilla = 0.468 mm [95% CI, 0.288, 0.648], and posterior mandible 0.559 mm [95% CI, 0.397, 0.72]), 2 to 5 years (anterior maxilla = 0.683 mm [95% CI, 0.224, 1.142], posterior maxilla = 0.645 mm [95% CI, 0.42, 0.87], and posterior mandible 0.563 mm [95% CI, 0.278, 0.849]). There were insufficient studies in the anterior mandible and with follow-up data over 5 years for quantitative synthesis. Within the limitations of this study, location within the maxillary and mandibular jaws does not seem to influence ΔMBL around internal connection bone level implants with fixed restorations. Although there may be a tendency for greater initial remodeling in the posterior mandible followed by long-term stability, additional studies are needed to evaluate this further. [ABSTRACT FROM AUTHOR]

Purpose: To assess the body of evidence of short versus regular implants after bone augmentation (BA) in the atrophic posterior mandible in the context of implant treatment success outcomes. Methods: Seven databases, two registries, and reference lists were searched for systematic reviews and meta-analysis (SR/MA), randomized controlled trials (RCTs) and longitudinal studies published in English, Spanish or German since 2012. Confidence in the SR/MA methodology was evaluated using AMSTAR-2 and the risk of bias of primary studies using Cochrane's RoB 2.0 and ROBINS-I. A random-effects meta-analysis and a meta-regression were performed for continuous and dichotomous outcomes. GRADE approach was used to assess the certainty of the evidence. Results: Eighteen SRs/MAs, most of them "critically low" and "low" confidence with substantial overlap, included 14 relevant RCTs with a high risk of bias. A cohort study with moderate risk of bias was added. Quantitative synthesis of 595 implants and 281 hemiarches/patients indicates that the use of short implants (< 10 mm) compared to regular implants and BA may reduce implant failure at 1-year follow-up, and marginal bone loss (MBL) at 3-, 5-, and 8-year follow-up; is likely to reduce the risk of biological complications at 1-, 3-, 5-, and 8-year follow-up; and may be the patient's preferred alternative. There is a correlation between bone height, MBL and biological complications. Conclusions: The available evidence partially suggests that the use of short implants could decrease implant failure, MBL, and biological complications, and increase patient satisfaction. However, given the need for further RCTs and real-world evidence to fully evaluate short- and long-term outcomes, it would be prudent for clinicians to carefully consider the individual needs and circumstances of the patients before deciding whether to use short implants. Trial registration PROSPERO CRD42022333526 [ABSTRACT FROM AUTHOR]

Introduction: The identification of skeletal remains is of paramount importance in medico-legal investigations. Identification of sex from skeletal remains is an important tool in forensic science. Mandibular ramus can be used for sex determination either on dry mandible or through orthopantomogram (OPG). Presence of a dense layer of compact bone makes it very durable and well preserved than many other bones. Mandibular ramus can be used to differentiate between sexes and it also expresses strong univariate sexual dimorphism. Aim and Objectives: The aim of the present study is to measure, compare, and evaluate various measurements of the mandibular ramus, observed in digital orthopantomographs and also to assess the usefulness of the mandibular ramus as an aid in gender determination. Materials And Method: A retrospective study is conducted using orthopantomographs of 50 subjects (25 males and 25 females) with age range between 21-50 years, taken using CS 8100 CARESTREAM Digital Panoramic machine (73 kVp, 12 mA, 13.9 s). This study is done using archival records from HPGDC, Shimla. Mandibular ramus measurements are carried out using GIMP 2.10.30 software. Results: In this study the data is tabulated and results are statistically analysed. [ABSTRACT FROM AUTHOR]

In the Shanshenmiaozui (SSMZ) fauna from Nihewan Basin, Canis chihliensis , Nyctereutes sp., Homotherium sp., Acinonyx sp., Lynx shansius and Pachycrocuta licenti have been identified. C. chihliensis is the dominant and best represented species whose fossil materials include crania, mandibles and postcranials, including nearly complete manus and pes. The giant cheetah Acinonyx sp. is only represented by postcranial skeletons (scapula, radius, proximal ulna and an almost complete manus), which represent the richest collection for its kind ever known in China. Nyctereutes sp. is only represented by a partial cranium and distal part of a humerus. Homotherium sp. is only represented by a partial lower m1. Lynx shansius is represented by a nearly complete mandible with p3 and m1 preserved in situ. The fossil materials of Pachycrocuta licenti include a juvenile mandible with dp2–4 and m1 attached, an isolated dp4 and a partial ascending ramus. The SSMZ carnivoran guild resembles those of the classic Nihewan fauna (CNF) and the Dmanisi fauna, which means they probably have a similar geologic age or slightly younger of the SSMZ fauna; and they also share the same open grassland/shrubland habitat. The postcranial bones of C. chihliensis and Acinonyx sp. from SSMZ represent the first records for their kinds in China. [ABSTRACT FROM AUTHOR]

Summary: A 15‐year‐old Hanoverian gelding was admitted for evaluation of a firm, expansive mass about 5 cm in diameter, in the horizontal ramus of the right mandible, between teeth 406 and 408. Histological examination revealed a highly invasive ameloblastoma with severe secondary fibrosis. Resection of the tumour was performed under general anaesthesia, a 4.5 locking compression plate with 14 holes was placed over the defect with eight locking screws, and the defect was filled with Cerasorb M. The horse received radiation therapy with a dose of 4.2 Gy every day for 10 consecutive days. Twenty months after surgery, the horse is in a good general condition and a repeat biopsy showed no signs of tumour recurrence. [ABSTRACT FROM AUTHOR]

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Sufficient bone volume is necessary for placing a dental implant in an ideal position. To restore severely insufficient bone volume, autogenous block graft procedures with various intraoral donor sites are presented in the literature. The aims of this retrospective study are to present the dimensions and volume of the potential ramus block graft site, and to evaluate possible effect of mandibular canal diameter and its position in relation to mandibular ramus block graft volume. Two-hundred cone-beam computed tomography (CBCT) images were evaluated. The maximum length, width, height, and volume of the potential ramus block graft site, mandibular canal diameter, mandibular canal–mandibular basis distance, and mandibular canal–crest distance were measured. Mandibular canal diameter, mandibular canal–crest distance, and mandibular canal–mandibular basis distance were 3.139 ± 0.446 mm, 15.376 ± 2.562, and 7.834 ± 1.285 mm, respectively. In addition, the dimensions of the potential ramus block graft sites were measured 11.156 ± 2.297 mm × 10.390 ± 3.420 mm × 8.816 ± 1.720 mm (height × length × width). Moreover, the potential ramus bone block volume was calculated as 1.076 ± 0.398 cm3. While a positive correlation was detected between mandibular canal–crest distance and the potential ramus block graft volume (r =.160, P =.025), a negative correlation was found between mandibular canal–mandibular basis distance and the potential ramus block graft volume (r = −.020, P =.001). Mandibular ramus is one of the predictable intraoral donor sites for bone augmentation procedures. However, ramus has some volumetric limitations related to its neighboring anatomic structures. It seems to be important to evaluate lower jaw in a 3-dimensional manner to prevent surgical complications. [ABSTRACT FROM AUTHOR]

Background: With the frequent use of Bisphosphonates (BPs), the morbidity of BP-related osteonecrosis of the jaw (BRONJ) is also increasing. However, the prevention and treatment of BRONJ is faced with enormous challenges. This study aimed to illuminate the influence of BP administration in the rat mandible and explore the feasibility of discriminating BRONJ lesion bone with Raman spectroscopy. Materials and methods: First, we explored the time- and mode-dependent effects of BP administration on the rat mandible with Raman spectroscopy. Second, the BRONJ rat model was constructed, and the lesion and healthy bone components were analyzed using Raman spectroscopy. Results: When only BPs were administered, no rats showed BRONJ symptoms, and no difference could be found in the Raman spectra. However, when combined with local surgery, six (6/8) rats showed BRONJ symptoms. The Raman spectra also showed a significant difference between the lesion and healthy bone. Conclusion: In the progression of BRONJ, BPs and local stimulation play an essential role. Both BPs administration and local stimulation need to be controlled to prevent BRONJ. Moreover, BRONJ lesion bone in rats could be discriminated with Raman spectroscopy. This novel method would become a complement in the treatment of BRONJ in the future. [ABSTRACT FROM AUTHOR]

Objective: This study aims to report the implant survival rate of dental implants of partially dentate patients in the anterior mandible and the potential risk indicators for implant failure. Materials and Methods: Patients with implant‐supported restorations of single or multiple teeth in the anterior mandible restored with fixed partial implant‐supported restorations were evaluated. Patient demographic data, implant placement timing, and loading protocol, biological and/or technical complications at the time of the last clinical and radiographic follow‐up visit were registered. Survival rate, success rate, and potential risk indicators for implant failure were calculated. Results: A total of 108 patients and 186 implants with a mean follow‐up period of 5.48 years (0.1–11.34 years) were included. The 11.3‐year cumulative survival rate was 90.9%. Immediate implant placement (OR = 2.75) (p =.08) and immediate implant loading (OR = 8.8) (p =.02*) indicated a higher risk of failure than late implant placement or loading. When combining both categories (type 1A), an OR = 10.59 (p =.04*) for implant failure was found compared to category 4C. Implants placed following static—computer‐assisted implant surgery (S‐CAIS) showed less risk of failure compared to freehand implant placement (OR = 0.18; 95% CI: 0.02–1.37) (p =.09). Conclusions: The survival rate of implants placed in the anterior mandible was considerably low (90.9%). S‐CAIS, late placement, and conventional loading are protective factor against implant failure in the anterior mandible. [ABSTRACT FROM AUTHOR]

The aim of this study was to investigate the value of 3D Statistical Shape Modelling for orthognathic surgery planning. The goal was to objectify shape variations in the orthognathic population and differences between male and female patients by means of a statistical shape modelling method. Pre-operative CBCT scans of patients for whom 3D Virtual Surgical Plans (3D VSP) were developed at the University Medical Center Groningen between 2019 and 2020 were included. Automatic segmentation algorithms were used to create 3D models of the mandibles, and the statistical shape model was built through principal component analysis. Unpaired t-tests were performed to compare the principal components of the male and female models. A total of 194 patients (130 females and 64 males) were included. The mandibular shape could be visually described by the first five principal components: (1) The height of the mandibular ramus and condyles, (2) the variation in the gonial angle of the mandible, (3) the width of the ramus and the anterior/posterior projection of the chin, (4) the lateral projection of the mandible's angle, and (5) the lateral slope of the ramus and the inter-condylar distance. The statistical test showed significant differences between male and female mandibular shapes in 10 principal components. This study demonstrates the feasibility of using statistical shape modelling to inform physicians about mandible shape variations and relevant differences between male and female mandibles. The information obtained from this study could be used to quantify masculine and feminine mandibular shape aspects and to improve surgical planning for mandibular shape manipulations. [ABSTRACT FROM AUTHOR]