Search Results (13)

Background: It has been suggested that the mandible may differ according to gender. The fact that the mandible and the anatomical structures on it show various changes with age and gender differences is important in gender and age determination. The aim of this study was to evaluate the morphometric variation in the condyle and coronoid processes and the gonial angle, which are anatomical structures forming the mandible, with gender and age. Methods: Cone beam CT images of 141 individuals (78 female, 63 male) were used in this study. The images of all patients were obtained with the same X-ray device; the images were obtained at 70 kVp, 10 mA, and a 32 s exposure time in accordance with the manufacturer’s recommendations. Images displayed with 0.3 mm voxel with the IRYS 15.0 program were examined in the axial, sagittal, and coronal planes, and measurements were taken. The gonial angle, coronoid notch, condyle height, condyle–coronoid distance, and sigmoid notch depths were evaluated. Results: The average age of 141 individuals was 43.21 ± 15.96 years, and 55.3% of them were female and 44.7% were male. The mean right gonial angle in females (128.66 ± 5.50°) was significantly higher than in males (125.68 ± 5.10°) (p < 0.005). Similarly, the mean left gonial angle in females (128.84 ± 5.97°) was significantly higher than in males (125.26 ± 4.89°) (p < 0.005). The sigmoid notch depth was found to be greater in men, with an average of 13.88 ± 2.46 mm, while in women, it had an average of 13.13 ± 1.80 mm, and this difference was statistically significant (p < 0.005). The relationship between the two sides’ coronoid notch height, sigmoid notch depth, condyle height, and condyle–coronoid distance and age groups was not statistically significant (p > 0.005). Conclusions: Overall, our findings indicate that the male mandible may have a longer condyle, a narrower gonial angle, and a wider sigmoid notch depth than that of females. It has been observed that ramus measurements such as condyle length and sigmoid notch depth may be important in gender discrimination, and the male mandible exhibits larger values in these parameters. No differences in parameters were observed between age groups. Full article

Introduction: Elbow primary stability is guaranteed by the anatomical congruency between the humeral trochlea and the greater sigmoid notch (GSN). Elbow dislocation typically occurs in a semi-extended position, but computed tomography (CT) scans are typically acquired at 90° of elbow flexion, which may misleadingly suggest that the apex of the coronoid aligns with the trochlear center of rotation. This study aims to evaluate the anatomical features of the coronoid and GSN in a dislocated versus non-dislocated group, demonstrating that a more prominent coronoid process is more commonly observed in elbows without dislocation compared to those with dislocation. Materials and Methods: A total of 50 CT scans, equally divided between dislocated elbows and non-dislocated elbows, were analyzed, and the critical coronoid angle (CCA) was measured on a specific slice of the CT scan (level of evidence III). The CCA was calculated from two lines that arise in the center of the GSN, with the first one crossing the coronoid tip and the second parallel to the posterior olecranon cortex. Results: A significant difference in the CCA (p < 0.001) between the two groups was highlighted. In particular, it was found that 14/25 patients from the dislocated elbow group had a CCA below or equal to 27°, and all the non-dislocated subjects had a CCA ≥ 27°. These preliminary results suggest that a CCA ≤ 27° could be a threshold for requiring further imaging of soft tissues or closer follow-up. This may result from either a hypoplastic coronoid process or a decreased concavity of the GSN. Based on the CCA values, a logistic regression model (DAM model) was proposed to associate a coefficient of protection to the CCA, the angle of flexion during dislocation (FdD), and a parameter X, which is a factor that encompasses the contribution of soft tissues. Conclusions: A low CCA is statistically more frequent in dislocated elbows versus non-dislocated ones, creating a specific anatomical condition. The CCA should be carefully evaluated by elbow surgeons to guide patient-specific treatment. The DAM model can permit the stratification of patients eligible for further diagnostic analysis. Full article

The aim of this study was to determine the influence of limb positioning on computed tomographic (CT) measurement of radio-ulnar incongruity (RUI) in canines. The sample population was comprised of twenty thoracic limbs harvested from ten adult canine cadaveric specimens of medium-size breeds without concurrent orthopedic disease. CT scans of each elbow were performed using two different flexion angles (90° and 135°) in combination with five different supination and pronation angles (−35°, −15°, 0°, 15° and 35°). The limbs were aligned using a custom-made fixation device. For each scan, RUI was measured at the apex (AMC) and base (BMC) of the ulnar medial coronoid process and compared with each elbow joint in the study. As the values followed a normal distribution and the one-factorial analysis of variance produced a significant result, a Dunnett post hoc test was performed to compare the individual test conditions pairwise for significant differences. The results show no significant differences in the measurement of RUI between 90° and 135° of elbow flexion. The RUI measured at the AMC showed significant maximum deviations (p < 0.001) of 18.14% at −15° and 15° and 31.31% at −35° and 35°. Measurement of RUI at the BMC showed no significant differences at 15° of pronation; 15° of supination resulted in small deviations of 5.51% (p < 0.001). Angulation of 35° resulted in average maximum deviations of 11.51% (p < 0.001). Supination resulted in greater changes in the RUI than pronation. This study concludes that pronation and supination affect the congruity of the radio-ulnar joint space, most evident at 35°. These findings should be considered during the positioning of the forelimbs for diagnostic purposes. Full article

This retrospective study aimed to evaluate a possible correlation between the characteristics of the mandibular ramus and lower third molar impaction by comparing a group of subjects with an impacted lower third molar and a second group with normal eruption for an early prediction of this pathology. This comparison was made using linear and angular measurements, which were taken on digital panoramic radiographs. Materials and methods: A total of 726 orthopantomographs (OPT) were examined, and 81 were considered suitable for the present study. The results were divided into two groups: a control group and an experimental group. The control group comprised 38 cases in which patients had at least one lower third molar that had erupted, and the experimental group comprised 43 cases in which patients had at least one lower third molar that was impacted or partially impacted. In total, 16 variables (11 linear, 4 angular, and 1 ratio) were determined and measured by an experienced observer. Results: The control group had a larger retromolar space, a larger impaction angle and a higher ratio of retromolar area to the third molar, compared to the experimental group. In contrast, the experimental group showed a deeper sigmoid notch depth than the control group did. In the control group, moderate positive correlations were found between both the length of the coronoid and the width of the third molar, and the retromolar space. Furthermore, in the experimental group, moderate positive correlations were found between both the angular condyle–coronoid process and the inclination of the lower posterior teeth, and the retromolar space. Conclusion: this study showed that the angle of a lower third molar, in relation to mandibular pain, can be an index for predicting tooth inclusion. Full article

Gender determination is the first step in forensic identification, followed by age and height determination, which are both affected by gender. This study assessed the accuracy of gender estimation using mandibular morphometric indices on panoramic radiographs of an Iranian population. This retrospective study evaluated 290 panoramic radiographs (145 males and 145 females). The maximum and minimum ramus width, coronoid height, condylar height, antegonial angle, antegonial depth, gonial angle, and the superior border of mental foramen were bilaterally measured as well as bicondylar and bigonial breadths using Scanora Lite. Correlation of parameters with gender was analyzed by univariate, multiple, and best models. All indices except for gonial angle were significantly different between males and females and can be used for gender determination according to univariate model. Condylar height, coronoid height, and superior border of mental foramen and ramus were still significantly greater in males than in females after controlling for the effect of confounders (p < 0.05). Based on the best model, a formula including five indices of bicondylar breadth, condylar height, coronoid height, minimum ramus width, and superior border of mental foramen was used for gender determination. Values higher than 56% indicate male gender, while lower values indicate female gender, with 81.38% specificity for correct detection of females and 88.97% sensitivity for correct detection of males. Despite the satisfactory results, future research should focus on larger populations to verify the accuracy of the present findings. Full article

There are significant discrepancies in the reported prevalence of condylar process fractures among all mandibular fractures (16.5–56%) in the available literature. In addition, it seems that the actual number of difficult-to-treat fractures of the mandibular head is unknown. The purpose of this study is to present the current incidence of the different types of mandibular process fractures with a special focus on mandibular head fractures. The medical records of 386 patients with single or multiple mandibular fractures were reviewed. Of the fractures found, 58% were body fractures, 32% were angle fractures, 7% were ramus fractures, 2% were coronoid process fractures, and 45% were condylar process fractures. The most common fracture of the condylar process was a basal fracture (54% of condylar fractures), and the second most common fracture was a fracture of the mandibular head (34% of condylar process fractures). Further, 16% of patients had low-neck fractures, and 16% had high-neck fractures. Of the patients with head fractures, 8% had a type A fracture, 34% had a type B fracture, and 73% had a type C fracture. A total of 89.6% of the patients were surgically treated with ORIF. Mandibular head fractures are not as rare as previously thought. Head fractures occur twice as often in the pediatric population than in adults. A mandibular fracture is most likely related to a mandible head fracture. Such evidence can guide the diagnostic procedure in the future. Full article

(1) Objective: This study aimed to evaluate the association between unilateral premolar scissors bite and mandibular symmetry of adults via the 3D distance mapping method. (2) Methods: A total of 53 cone-beam computed tomography (CBCT) images of adults with unilateral premolar scissors bite were set as study samples. A total of 53 age- and sex-matched samples without scissors bite were in the control group. Three-dimensional mandibular models and seven mandibular functional units, including condylar process (Co), coronoid process (Cr), mandibular ramus (Ra), mandibular angle (Ma), alveolar process (Ap), mandibular body (Mb), and chin process (Ch) were constructed and mirrored. After superimposition of the original and the mirrored models, 3D distance maps and deviation analysis were performed to evaluate the mandibular symmetry and morphology. (3) Results: In the study group, the matching percentages of the entire mandible (50.79 ± 10.38%), Ap (67.00 ± 12.68%), Mb (66.62 ± 9.44%), Ra (62.52 ± 11.00%), Ch (80.75 ± 9.86%), and Co (62.78 ± 13.56) were lower than that of the entire mandible (58.60 ± 5.52) (p < 0.01), Ap (73.83 ± 8.88%) (p < 0.01), Mb (72.37 ± 8.69%) (p < 0.01), Ra (68.60 ± 7.56%) (p < 0.01), Ch (85.23 ± 6.80%) (p < 0.01), and Co (67.58 ± 10.32%) (p < 0.05) in the control group. However, Cr and Ma showed no significant difference (p > 0.05). (4) Conclusions: The 3D distance mapping method provided a qualitative and quantitative mandibular symmetry and morphology assessment. Mandibular asymmetry was found in adults with unilateral premolar scissors bites. Mandibular functional units, including the alveolar process, mandibular body, mandibular ramus, chin process, and condylar process, showed significant differences, while no significant difference was observed in the coronoid process and mandibular angle. Full article

Study Design: In the year 2020, we saw the emergence of severe acute respiratory syndrome coronavirus 2 causing COVID-19 into a full blown pandemic. This resulted in constraints on healthcare resources, and the attention was shifted to reduce cross contamination and prevent spreader events.Maxillofacial trauma carewas also affected similarly, and most of the cases were managed by closed reduction whenever possible. A retrospective study was conducted to document our experience in treating maxillofacial trauma cases before and after nationwide lockdown due to COVID-19 pandemic in India. Objective: The objective of the study was to compare the effect of pandemic in reported pattern ofmandibular trauma and the result of closed reduction procedures in the management of single or multiple fractures in mandible during this time period. Methods: The study was conducted in the Department of Oral and Maxillofacial Surgery, Maulana Azad institute of Dental Sciences, Delhi, for a period of 20 months, that is, 10 months before and after nationwide lock down which was effective from 23 March 2020 due to COVID-19 pandemic. The cases were grouped into Group A (those reporting from 1 June 2019 to 31 March 2020) and Group B (those reporting from 1 April 2020 to 31 January 2021). Primary objectives were assessed and compared according to etiology, gender, location of the mandibular fractures, and treatment provided. Quality of life (QoL) associated with the treatment outcome by closed reduction was assessed after 2 months as a secondary objective using General Oral Health Assessment Index (GOHAI) in Group B. Results: A total of 798 patients sought treatment for mandibular fractures and included 476 patients in Group A and 322 in Group B. The groups showed similar age and male: female ratio. Cases showed a steep fall during first wave of pandemic, and most of the cases occurred as result of RTA followed by fall and assault. The fractures due to fall and assault showed an obvious rise during the lockdown period. There were 718 (89.97%) patients having exclusive mandibular fractures and 80 (10.03%) patients having involvement of both mandible and maxilla. Single fractures of mandible constituted 110 (23.11%) and 58 (18.01%) in Group A and B, respectively. 324 patients (68.07%) and 226 patients (70.19%) had multiple fractures involving mandible in respective groups. Parasymphysis of mandible was most commonly involved (24.31%) followed closely by unilateral condyle (23.48%) then Angle and Ramus of mandible (20.71%) with coronoid being the least fractured. During the initial 6 months after lockdown, all the cases were treated successfully using closed reduction. GOHAI QoL assessment conducted in cases having exclusive mandibular fracture (210 Multiple, 48 Single) showed favorable results with significant (p < 0.05) difference between the single and multiple fractures. Conclusions: After one and half years and recovering fromthe secondwave of pandemic that hit the country, we have come to understand COVID-19 better and embraced better management protocol. The study reveals that IMF remains the gold standard for the management of most of the facial fractures in pandemic situations. Itwas evident fromthe QoL data thatmost of the patients were able to carry out their day-to-day functions adequately. As the country prepares for a third wave of pandemic, management ofmaxillofacial trauma by closed reduction will remain the norm for most unless indicated otherwise. Full article

Apart from genetics, environmental factors, such as food consistency, may affect craniofacial morphology and development. The present systematic review aims to systematically investigate and appraise the available evidence regarding the effect of diet consistency on the anatomical structures of the basal bone of the rat mandible. The search was performed without restrictions in five databases (PubMed, Scopus, Web of Science, ProQuest Dissertations and Theses Global, including grey literature) and hand searching through January 2022. A total of 14,904 references were initially identified, and 16 articles were finally included in the systematic review. Rats that consumed hard diets were found to exhibit an increase inbigonial width, corpus height, condylar depth, condylar base inclination, condylar process inclination, mandibular plane inclination, height and length of angular process, mandibular body height, depth of antegonial notch, growth rate in the gonial angle, angular process convexity and height of condylar process. It was also noted that mandibular depth, mandibular height, ramus angle and angle between the angular process and mandibular plane were decreased in rats that were fed with a hard diet. On the other hand, there were conflicting results about the growth of mandibular length and width, corpus length, mandibular body length, ramus height, condylar length and width, gonial angle and height of coronoid process. From the abovementioned results, it can be concluded that food consistency may affect the morphology of anatomical structures and the overall growth and development of rat mandibles in various ways. Full article

Ankyloses in the area of the temporomandibular joint (TMJ) are mentioned as a potential etiological factor of mandibular growth disorders and facial asymmetry. The aim of this case study was to evaluate the changes in the mandible of a child with zygomatic-coronoid ankylosis during the first five years of life, in which two adhesion release procedures were performed. The adopted symmetrical approach is based on the assumption of symmetry of the structure of the stomatognathic system in relation to the sagittal median plane. However, the assessment of pathological changes in the structure of the skeletal system was performed using an asymmetrical approach. Computed tomography techniques and a system of computer-aided diagnosis (CAD) were used in the case study. During the child’s growth, linear and angular measurements were made thrice (at the age of 16, 25 and 54 months). The degree of asymmetry was estimated in the measurements made on the right and left sides of the three-dimensional mandible. Unilateral congenital hypoplasia of the articular process and zygomatic-coronoid adhesion caused asymmetrical growth of the mandible in the child along with shortening of the mandibular branch and body on the damaged side and a visible difference in the size of the mandibular angles. Removal of the adhesions during surgical procedures made it possible to reduce the asymmetry of the mandible and catch-up growth, although at the age of five, the mandible was still smaller than the mandible in healthy peers. It was shown that the early adhesion release procedures supported by the CAD analysis enabled the restoration of mandibular symmetry. Full article

This tutorial outlines the details of the AOCMF image-based classification system for fractures of the mandible at the precision level 2 allowing description of their topographical distribution. A short introduction about the anatomy is made. Mandibular fractures are classified by the anatomic regions involved. For this purpose, the mandible is delineated into an array of nine regions identified by letters: the symphysis/parasymphysis region anteriorly, two body regions on each lateral side, combined angle and ascending ramus regions, and finally the condylar and coronoid processes. A precise definition of the demarcation lines between these regions is given for the unambiguous allocation of fractures. Four transition zones allow an accurate topographic assignment if fractures end up in or run across the borders of anatomic regions. These zones are defined between angle/ramus and body, and between body and symphysis/parasymphysis. A fracture is classified as “confined” as long as it is located within a region, in contrast to a fracture being “nonconfined” when it extents to an adjoining region. Illustrations and case examples of mandible fractures are presented to become familiar with the classification procedure in daily routine. Full article

As the angle is a weak region in the continuity of mandible, so it is more prone to fracture. It has been proven time and again that coronoid fracture results from a strong sudden contraction of temporalis. Muscular forces influence the remodeling of bones. Orofacial dystonia is a centrally mediated disease in which there is an uncontrolled spasmodic contraction of facial and masticatory muscles. This continuous force applied over a long period of time has the potential to unfavorably remodel or weaken bone. A case is presented in which the dystonic action of facial musculature gradually resorbed the bone to such an extent that there was spontaneous fracture at the right angle of mandible as well as the contra lateral coronoid. Management of this fracture posed a challenge at every step eventually leading to resection of the ramus-condyle unit. No case has been reported so far in the literature where dystonic movements have resulted in fracture of the mandible. Full article

Systemic sclerosis (SSc) is a multisystem connective tissue disease of unknown etiology. The hallmark of SSc is scleroderma, referring to the presence of thickened, hardened skin. Oral and maxillofacial manifestations of the disease are numerous including masklike appearance, trismus, muscular atrophy, thin atrophied lips, secondary microstomia, xerostomia, rigidity of tongue and lips, widening of the periodontal ligament space, trigeminal neuralgia, and resorption of the mandible. A 35-year-old woman with limited cutaneous SSc presented with bilateral mandibular condylysis, severe class II mandibular deficiency, and large anterior open bite and limited range of mandibular opening at 27 mm. Surgical correction consisted of bilateral total temporomandibular joint reconstruction with stock prostheses combined with Le Fort I maxillary impaction and functional advancement genioplasty. This resulted in a functional occlusion with elimination of her open bite and a more esthetic profile. Her occlusion has remained stable at 7 months. The incidence of mandibular resorption in SSc has been found to be 20% to 33%. The mandibular angles are most commonly involved (37.6%), followed by the condyle (20.8%), coronoid process (20.0%), and the posterior border of the ascending ramus (14.4%). Bilateral condylysis is present in 13.7% of the cases. Very few cases of surgical correction of malocclusion induced by SSc-related condylysis have been reported in the literature. To the best of our knowledge, this is the first case report of bilateral condylysis from SSc where surgical replacement of the resorbed condyles was attempted. Bilateral total temporomandibular joint replacement can give these patients a functional occlusion, improved facial balance, and improved quality of life. Full article