Purpose: Maxillofacial trauma resulting from falls in elderly patients is a major social and health care concern. Most of these traumatic events involve mandibular fractures. The aim of this study was to analyze stress distributions from traumatic loads applied on the symphyseal, parasymphyseal, and mandibular body regions in the elderly edentulous mandible using finite-element analysis (FEA).
Materials And Methods: Computerized tomographic analysis of an edentulous macerated human mandible of a patient approximately 65 years old was performed. The bone structure was converted into a 3-dimensional stereolithographic model, which was used to construct the computer-aided design (CAD) geometry for FEA. The mechanical properties of cortical and cancellous bone were characterized as isotropic and elastic structures, respectively, in the CAD model. The condyles were constrained to prevent free movement in the x-, y-, and z-axes during simulation. This enabled the simulation to include the presence of masticatory muscles during trauma. Three different simulations were performed. Loads of 700 N were applied perpendicular to the surface of the cortical bone in the symphyseal, parasymphyseal, and mandibular body regions. The simulation results were evaluated according to equivalent von Mises stress distributions.
Results: Traumatic load at the symphyseal region generated low stress levels in the mental region and high stress levels in the mandibular neck. Traumatic load at the parasymphyseal region concentrated the resulting stress close to the mental foramen. Traumatic load in the mandibular body generated extensive stress in the mandibular body, angle, and ramus.
Conclusions: FEA enabled precise mapping of the stress distribution in a human elderly edentulous mandible (neck and mandibular angle) in response to 3 different traumatic load conditions. This knowledge can help guide emergency responders as they evaluate patients after a traumatic event.
Download full-text PDF |
Source |
---|---|
http://dx.doi.org/10.1016/j.joms.2014.10.014 | DOI Listing |
Am J Orthod Dentofacial Orthop
December 2024
Discipline of Orthodontics, School of Dentistry, Faculty of Medicine and Health, The University of Sydney, Sydney, Australia; Department of Orthodontics, Sydney Dental Hospital, Sydney Local Health District, Sydney, Australia; Division of Orthodontics, University Clinics of Dental Medicine, Faculty of Medicine, University of Geneva, Geneva, Switzerland. Electronic address:
Introduction: The dentoskeletal effects of clear aligner treatment (CAT) with Invisalign vs temporary skeletal anchorage device-anchored Sydney intrusion spring (SIS) were compared in consecutively treated growing patients with anterior open bite using cone-beam computed tomography scans.
Methods: Fifteen adolescents treated exclusively with Invisalign, and 14 with SIS (first-phase treatment) were assessed retrospectively. Rigid-wise, voxel-based registration of pretreatment and posttreatment cone-beam computed tomography scans were performed using the anterior cranial base, maxillary plane, and mandibular body as reference regions.
Vet Sci
December 2024
Department of Pathology, Division of Pathomorphology and Veterinary Forensics, Faculty of Veterinary Medicine, Wroclaw University of Environmental and Life Sciences, 50-375 Wroclaw, Poland.
Filling post-extraction alveoli with hydroxyapatite-based materials is becoming an increasingly common procedure in veterinary dentistry. In dogs, tooth roots vary in structure depending on the weight of the dog, but data on tooth length and volume have not yet been described. This study aimed to establish reference data on tooth root length and post-extraction alveolar volume for mature maxillary and mandibular incisors and canines in dogs.
View Article and Find Full Text PDFDent J (Basel)
November 2024
Department of Pediatrics, Faculty of Medicine, Juntendo University, Tokyo 113-8421, Japan.
: This study aimed to examine the connection between craniofacial morphology, particularly the horizontal and vertical dimensions of the mandible, and the severity of obstructive sleep apnea (OSA) in non-obese adult males by utilizing a cephalometric analysis and introducing a new skeletal ratio index. : A cohort of 44 non-obese adult males with OSA, diagnosed via the apnea-hypopnea index (AHI) from polysomnographic recordings, was evaluated using a lateral cephalometric analysis. OSA severity was classified as mild (5 ≤ AHI < 15) in 19 patients, moderate (15 ≤ AHI < 30) in 15 patients, and severe (AHI ≥ 30) in 10 patients.
View Article and Find Full Text PDFTissue Eng Part A
December 2024
Department of Bioengineering, Swanson School of Engineering, University of Pittsburgh, Pittsburgh, Pennsylvania, USA.
Long bone and craniofacial bone fractures amount to an overwhelming expenditure for patients and health care systems each year. Overall, 5-10% of all bone fractures result in some form of delayed or nonunion fractures. Nonunions occur from insufficient mechanical stabilization or a compromised wound environment lacking in vasculature and progenitor cells.
View Article and Find Full Text PDFNat Sci Sleep
December 2024
Department of Otorhinolaryngology Head and Neck Surgery, the Second Affiliated Hospital of Xi'an Jiaotong University, Xi'an, People's Republic of China.
Purpose: Aimed to analyze the developmental characteristics of craniofacial structures and soft tissues in children with obstructive sleep apnea (OSA) and to establish and evaluate prediction model.
Methods: It's a retrospective study comprising 747 children aged 2-12 years (337 patients and 410 controls) visited the Department of Otolaryngology-Head and Neck Surgery, the Second Affiliated Hospital of Xi'an Jiaotong University (July 2017 to March 2024). Lateral head radiographs were obtained to compare the cephalometric measurements.
Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!