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Introduction The objective of this research was to analyze the effect of orthodontic treatment with maxillary permanent first molar extraction on the occlusal stress distribution and displacement in the human skull. Methods A 3-dimensional finite element model was constructed on the basis of a computed tomography scan, and it was used as the pretreatment model. The software used for geometric modeling was Solid Works (Dassault Systemes, Paris, France). For the extraction model, the maxillary permanent first molar was removed, followed by a repositioning of the anterior and posterior segments to create a space closure model. Stress distribution was evaluated under the simulation of 1000 N for occlusal forces and 400 N for masseter muscle force. Results The highest von Mises stress was observed at the zygomatic process of the temporal bone across all 3 models (25 MPa), whereas stress at the pterygomaxillary suture area was almost 50% less. However, the stress in the pterygomaxillary suture area was lowest in the extraction model (18%) and space closure (30%). Stress in the zygomatic process of the frontal bone and frontal process of the maxilla increased from pretreatment to extraction model followed by space closure model. Conclusions The occlusal forces were transferred through maxillonasal, maxillozygomatic, and maxillopterygoid stress trajectories. The mesial displacement of the molars may weaken the role of maxillopterygoid stress trajectory while strengthening the role of maxillonasal stress trajectory.

Zygomatic root abscess is a rare extracranial extratemporal complication of otitis media. To the best of our knowledge, there are only a few scattered cases of zygomatic root abscesses reported in the literature. We present an unusual case of a zygomatic root abscess in a 24 years old adult. He presented with one month duration of right zygomatic swelling. Otoscopic examination revealed superior and posterior external auditory canal wall sagging with an intact tympanic membrane. High Resolution Computed Tomography (HRCT) temporal bone revealed a rim enhancing lesion lateral to the zygomatic process with fluid filled mastoid air cells. He was managed with antibiotics and staged surgical interventions. He recovered well. Our case serves to shed light on the pathways of infection, clinical manifestations and timely staged surgical intervention in this rare pathology.

Background: Pneumatized articular eminence (PAT) and roof of the glenoid fossa (PRGF) are recognized when accessory air cells are found within the zygomatic process of the temporal bone. Pneumatization in this region facilitates the spread of tumors and fractures. During Zygomatic implant placement and TMJ surgical procedures, namely eminectomy and miniplate insertions, various complications might arise due to pneumatized PAT and PRGF. Cone-beam computed tomography (CBCT) provides reliable and accurate information to determine the characteristics, the extent of pneumatization, and its relationship to the adjacent structures. So, recognizing the variations of PAT and PRGF in different populations is of clinical importance. Objective: The purpose of this study was to assess the prevalence of pneumatization of articular tubercle (PAT) and pneumatization of PRGF in the North- East Indian population by using CBCT. Materials and Methods: The study was carried out among 500 patients. The prevalence and significance of differences among the variables were carried out by analysis of variance (ANOVA) and Chi-square test. Data were analyzed by using Statistical Package for the Social Sciences (SPSS) software program, version 21 (IBM). Results: The mean age with pneumatization was 45.27 ± 18.00 years. The prevalence of PAT and PRGF was found to be 24.6% and 24.4%, respectively. Bilateral PAT was detected in (6%) patients. The occurrence of unilateral PAT cases was found to be more than bilateral PAT cases (

Fractures of the Zygomatic-Maxillary Complex (CZM) are considered one of the most common fractures of the facial region, due to their projection from the bones that make up this region. They represent about 25% of all facial fractures and are usually the result of industrial accidents, sports injuries and interpersonal fights. This study aims to review the literature on fractures of the zygomatic complex, emphasizing its diagnosis, surgical protocol and possible complications after operative treatment. For the construction of this article, a bibliographic survey was carried out in the SciVerse Scopus, Scientific Electronic Library Online (Scielo), Virtual Health Library (BVS) and U.S. National Library of Medicine (PUBMED). Articles from the years 2000 to 2022 were selected. From the literary search, 22 articles were included in the present study. The management of zygomatic fractures remains a challenge and controversies persist. New technologies and approaches may ultimately allow for more accurate correction of fractures when using less invasive or less visible access. The surgeon must carefully evaluate the different tools and strategies available to provide patients with surgical options that provide the most stable and accurate reduction while also minimizing iatrogenic morbidity. Las fracturas del Complejo Cigomático-Maxilar (CZM) se consideran una de las fracturas más comunes de la región facial, debido a su proyección de los huesos que componen esta región. Representan alrededor del 25% de todas las fracturas faciales y suelen ser el resultado de accidentes laborales, lesiones deportivas y peleas interpersonales. Este estudio tiene como objetivo revisar la literatura sobre fracturas del complejo cigomático, enfatizando su diagnóstico, protocolo quirúrgico y posibles complicaciones después del tratamiento quirúrgico. Para la construcción de este artículo se realizó un levantamiento bibliográfico en SciVerse Scopus, Scientific Electronic Library Online (Scielo), Virtual Health Library (BVS) y U.S. Biblioteca Nacional de Medicina (PUBMED). Se seleccionaron artículos de los años 2000 a 2022. De la búsqueda literaria, 22 artículos fueron incluidos en el presente estudio. El manejo de las fracturas cigomáticas sigue siendo un desafío y persisten las controversias. En última instancia, las nuevas tecnologías y enfoques pueden permitir una corrección más precisa de las fracturas cuando se utiliza un acceso menos invasivo o menos visible. El cirujano debe evaluar cuidadosamente las diferentes herramientas y estrategias disponibles para brindarles a los pacientes opciones quirúrgicas que brinden la reducción más estable y precisa y al mismo tiempo minimicen la morbilidad iatrogénica. As fraturas do complexo Zigomático-Maxilar (CZM) são consideradas uma das fraturas mais comuns da região facial, devido a sua projeção dos ossos que compõem essa região. Representam cerca de 25% de todas as fraturas faciais e são normalmente resultado de acidentes industriais, lesões esportivas e brigas interpessoais. Este estudo possui como objetivo revisar a literatura acerca das fraturas do complexo zigomático, enfatizando seu diagnóstico, protocolo cirúrgico e possíveis complicações pós tratamento operatório. Para a construção deste artigo foi feito um levantamento bibliográfico nas bases de dados SciVerse Scopus, Scientific Eletronic Library Online (Scielo), Biblioteca Virtual em Saúde (BVS) e U.S. National Library of Medicine (PUBMED). Foram selecionados artigos contemplados entre os anos de 2000 a 2022. A partir da busca literária, 22 artigos foram contemplados no presente estudo. O manejo das fraturas zigomáticas continua sendo um desafio e as controvérsias persistem. Novas tecnologias e abordagens podem, em última análise, permitem uma correção mais precisa de fraturas ao usar acesso menos invasivo ou menos visível. O cirurgião deve avaliar cuidadosamente as diferentes ferramentas e estratégias disponíveis para fornecer às pacientes opções cirúrgicas que fornecem o mais estável e redução precisa, minimizando também a morbidade iatrogênica.

Background After cranioplasty, in many cases a not negligible soft tissue defect remains in the temporozygomatical area, also referred to as a hollowing defect of the temple. Objective To assess the precise localization and volume of the hollowing defect, to optimize future cranioplasties. Methods CT data of patients who received craniectomy and conventional CAD cranioplasty in our institution between 2012 and 2018 were analyzed. CT datasets prior to craniectomy and after cranioplasty were subtracted to quantify the volume and localization of the defect. Results Out of 91 patients, 21 had suitable datasets. Five cases had good cosmetic results with no defect visible, 16 patients had an apparent hollowing defect. Their average defect volume was 5.0 cm3 ± 4.5 cm3. The defect localizations were in the area behind the zygomatic process and just below the superior temporal line, covering an area of app. 3x3 cm2. Surgical attempts of temporal muscle restoration were more often found in reports of good results (p Conclusion This work supplies evidence for the indication of a surgical corrective during cranioplasty in the small but cosmetically relevant area of the “frontozygomatic shadow”. Based on our 3D data analysis, future focused surgical strategies may obtain better aesthetical results here.

Background The exophthalmos and class III malocclusion seen in Crouzon syndrome can be treated by Le Fort III advancement/distraction. However, reconstructive options for zygomatic retrusion are limited. The authors describe the repair of isolated exorbitism in a patient with Crouzon syndrome, via bilateral zygomatic rotation-advancement. Methods A 34-year-old woman with Crouzon syndrome complained of exorbitism and malar hypoplasia. Four years prior, she declined Le Fort III advancement and underwent orthodontic/orthognathic correction of malocclusion. Radiographs were used to develop a computerized surgical plan. Bilateral periorbital osteotomy with advancement/rotation of the zygomatic process was performed using custom osteotomy guides and plates. Images obtained immediately postoperative and 3- and 19-month postoperative were compared to assess surgical stability, accuracy, and soft tissue changes. Results Decreased globe exposure and increased malar prominence have improved facial balance. Superimposed pre- and postoperative radiographs demonstrate bilateral advancement of the zygomatic body and inferior orbital rim. Superimposition of immediate postoperative and 19-month radiographs showed no relapse. Soft tissue histogram showed increased prominence of the malar eminence, lateral orbital rim, and cheek. Conclusions Zygomatic rotation-advancement proved a safe, effective, stable, and predictable treatment for isolated malar hypoplasia in a patient with Crouzon syndrome. Virtual planning can enhance novel complex craniofacial procedures.

Osteochondroma of mandibular condyle is an uncommon entity. In the temporomandibular region, they usually present as restriction in mouth opening and pain in the joint. They can grow to a large size to impinge upon the cranial fossa. We present the imaging features of two such rare cases, one was giant condylar osteochondroma and the other one was condylar osteochondroma associated with contralateral osteochondroma of the zygomatic process of the temporal bone and congenital block cervical vertebrae. Computed tomography, magnetic resonance imaging of the temporomandibular joint and bone scan findings are discussed in detail along with the follow-up of patients.

This is a prospective observational cross sectional study comprising of 57 patients who were having symptoms of chronic rhinosinusitis which were evaluated with the help of computed tomography scan (coronal and axial sections) to measure the thickness of all walls of maxillary sinus and it’s volume. Computed tomographic imaging of sinonasal region has become the gold standard in the evaluation of patients with chronic sinusitis. The maxillary sinus is pyramidal in shape with lateral wall of nose forming its base and its apex is directed towards zygomatic process. All three dimensions of the maxillary sinus were measured and the volume of each maxillary sinus was also calculated. Hyperostosis of maxillary sinus tended to increase maxillary sinus walls thickness which ultimately results into decrease in maxillary sinus volume in chronic rhinosinusitis patients.

The temporomandibular joint (TMJ), the most complex and evolved joint in humans, presents two articular surfaces: the condyle of the mandible and the articular eminence (AE) of the temporal bone. AE is the anterior root of the zygomatic process of the temporal bone and has an anterior and a posterior slope, the latter being also known as the articular surface. AE is utterly important in the biomechanics of the TMJ, as the mandibular condyle slides along the posterior slope of the AE while the mandible moves. The aim of this review was to assess significant factors influencing the inclination of the AE, especially modifications caused by aging, biological sex or edentulism. Studies have reported variations in the angles of the slopes of the AE between medieval and recent human dry skulls, as well as between subjects of different racial origin. Recent articles have emphasized the significant role that tooth loss has on the flattening of the AE. Although some papers have described biological sex or age as factors which could be associated with differences in AE angulations, edentulism seems to be a significant factor impacting on the inclination of the AE.

Trigeminal neuralgia is a painful condition, usually treated through surgical procedures focusing on the foramen ovale (FO). A detailed localization of FO relative to reference landmarks is therefore crucial to avoid possible complications.The present study aims at assessing the position of FO according to the surrounding bone structures: 100 CT-scans of patients, equally divided between sexes, aged between 18 and 86 years were examined. From each subject, the 3D models of FO and the maxillary bones, the zygomatic bones and the zygomatic process of the temporal bones were segmented through ITK-SNAP software. The distance between the center of the FO and subnasale, zygion, and the upper edge of the zygomatic bone at the origin of the frontal process were measured on 3D models. On CT-scans three cranial measurements were taken as well (distance between anterior and posterior nasal spine, upper facial height and bizygomatic breadth).Statistically significant differences in the three distances according to side and sex were assessed through two-way ANCOVA test, using the three cranial measurements (ANS-PNS, NP, ZZ) as covariates (P

Although the middle temporal artery is used for maxillofacial and otological flap surgeries, the anatomical knowledge of the artery is insufficient to corroborate its usage. This study has investigated the interrelationship between the artery and the temporal fascia to enhance its availability. The middle temporal artery was dissected in ten cadavers, and its spatial relations with the temporal fascia and muscle and the adjacent structures were examined. The middle temporal artery arose behind the mandibular head or neck and in front of the external acoustic meatus. It penetrated the temporal fascia external to the junction between the zygomatic process and the supramastoid crest. The artery gave off a thin branch in the space between the superficial and the deep layers of the fascia and is divided into two branches piercing the deep layer to supply the temporalis. The anterior branch anastomosed with the deep temporal artery; furthermore, it gave off the slender ramus coursing on the base of the zygomatic process to communicate with the masseteric artery. The posterior branch passed along the supramastoid crest, gave off a slender ramus and ascended in the groove of the temporal bone. The branching pattern of the middle temporal artery and its positions relative to the temporal fascia and the landmark structures are helpful in identifying the artery, designing favourable flaps and avoiding unfavourable bleeding during surgery. They are also beneficial in developing the clinical usage of the artery.

Objective: The aim of this study was to evaluate the thickness of the zygomatic-maxillary cortical bone using computed tomography in different skeletal patterns. Methods: A total of 54 patients of both sexes, divided into three groups according to the vertical skeletal pattern, were evaluated for cortical bone thickness of the anterior slope of the zygomatic process of the maxilla, using cone beam computed tomography. Measurements were made at 2mm, 4mm, 6mm, 8mm and 10mm above from first molar mesial root apex. Vertical skeletal pattern was determined by Frankfurt mandibular angle (FMA). Results: The hyperdivergent pattern had the lowest cortical thickness value, nevertheless, no patient in the hyperdivergent group presented cortical thickness exceeding 2mm, and no patient in the hypodivergent group presented cortical thickness less than 1mm. However, the correlation between cortical thickness and mandibular plane angle was weak and not significant. Conclusion: Although higher prevalence of thick cortical was observed in the hypodivergent patients, and thin cortical groups in the hyperdivergent group, the vertical skeletal pattern could not be used as determinant of the zygomatic-maxillary cortical thickness. RESUMO Objetivo: O objetivo do presente estudo foi avaliar a espessura da cortical óssea zigomático-maxilar por meio de tomografia computadorizada em diferentes padrões esqueléticos. Métodos: Um total de 54 pacientes de ambos os sexos, divididos em três grupos, de acordo com o padrão esquelético vertical, foi avaliado quanto à espessura da cortical óssea na vertente anterior do processo zigomático da maxila, por meio de tomografia computadorizada de feixe cônico. As medidas foram feitas a 2mm, 4mm, 6mm, 8mm e 10mm acima do ápice da raiz mesial do primeiro molar. O padrão esquelético vertical foi determinado pelo Ângulo do Plano Mandibular (FMA). Resultados: O padrão hiperdivergente apresentou o menor valor de espessura de cortical. No entanto, nenhum paciente do grupo hiperdivergente apresentou espessura cortical superior a 2mm e nenhum paciente do grupo hipodivergente apresentou espessura cortical inferior a 1mm. No entanto, a correlação entre a espessura da cortical e o ângulo do plano mandibular foi fraca e não significativa. Conclusão: Embora tenha havido uma maior prevalência de cortical espessa no grupo hipodivergente e cortical fina no grupo hiperdivergente, o padrão esquelético vertical não pode ser utilizado como determinante da espessura cortical zigomático-maxilar.

Background : Craniomandibular osteopathy (CMO) is a degenerative, osteopetrotic, and self-limiting bone disease that is rare in the canine species. The most affected bones and joints are the branches of the mandible, tympanic bulla, and temporomandibular joint (TMJ) with generalized thickening of the bone trabeculae, increased lines of bone cementation, and bone proliferation. The aim of the present study was to evaluate 2 cases of CMO in mixed-breed dogs belonging to the same litter sent to the Laboratorio Regional de Diagnostico, Faculdade de Veterinaria, Universidade Federal de Pelotas (LRD / FV / UFPel). Cases : Three canines (mixed-breed, 2 female and 1 male) belonging to the same litter presented at eight months of age with increases in volume and pain in the face, difficulties in moving the jaw, anorexia, and sialorrhea. The 2 female dogs were euthanized and sent to LRD / FV / UFPel for necropsy. The animals underwent radiography of the left and right lateral and dorsoventral lateral projections in the imaging sector of the Hospital de Clinicas Veterinaria (HCV) at UFPel. During the necropsy, fragments of organs from the abdominal and thoracic cavities, as well as the central nervous system and head bones, were collected and fixed in 10% buffered formalin. The tissue samples were cleaved, processed routinely, embedded in paraffin, cut into sections of 3 µm thickness, and stained using hematoxylin and eosin (HE). The bone fragments were decalcified in a 50/50 solution of 8% hydrochloric acid and 8% formic acid and subsequently cleaved and stained with HE. The head and jaw of one of the animals was dissected and subjected to maceration in water at room temperature. Radiographic examination of the two remaining animals showed irregular and exuberant bone proliferation in the mandible and temporomandibular region. In the tympanic bullae, occipital bone, and zygomatic process, thickening of the structures was observed with increased opacity. On necropsy, the animals were cachectic with marked muscle atrophy and increased volume of the mandibular branches and head bones, in addition to marked edema in the adjacent subcutaneous tissue. The regional lymph nodes were enlarged, and in one of the animals, bilateral lesions in the femurs were also observed. In the head subjected to biological maceration, areas of bone proliferation and rarefaction were observed, with increased volume and destruction of the TMJ. On histopathological evaluation of the ventral portion of the mandibular bodies, a network of bony trabeculae was observed, composed of a chondroid matrix with different degrees of mineralization. The cortical portion of the bones exhibited loss of lamellar compactness, with greater spread of the bone trabeculae. The bone trabeculae were perpendicular to the long axis of the cortical of the mandible and were distributed in the medullary spaces, presenting some dense foci of inflammatory infiltrates composed predominantly of neutrophils, lymphocytes, and plasma cells. Discussion : The breeds most predisposed to developing CMO are the West Highland White Terrier and Scottish Terrier; however, the disease has also been described in other non-Terriers. Nevertheless, there are no descriptions in the literature of mixed-breed animals (SRD), with this report being the first of CMO in SRD dogs. The bones most frequently affected in CMO are those of the head. In Terrier dogs, the TMJ is also affected. In the cases of this study, severe CMO occurred, affecting both the head bones and TMJ, and in 1 of the animals, it also affected the femurs. Although CMO has not previously been reported in SRD dogs, the condition can seriously affect these animals, and differential diagnosis should always be made. Keywords : degenerative bone disease, bone proliferation, lion jaw, TMJ. Titulo: Osteopatia craniomandibular em caes sem raca definida Descritores: doenca ossea degenerativa, proliferacao ossea, mandibula de leao, ATM.

Lateral craniofacial skeleton is a complex anatomical area and presents unique challenges for reconstruction. Important aesthetic regions for lateral facial region include ear, lateral aspect of the forehead subunit, temple, cheek subunits – zygomatic and mandibular, and neck. Lateral craniofacial skeleton includes the zygomatic process, zygoma, temporal bone, mandible – coronoid, condyle, temporomandibular joint, ramus, angle and posterior body, maxilla. Characteristics of the involved structures must be thoroughly understood and the resultant consequences when these structures are removed. For reconstructive purposes, the defects can be classified into auricle only, cutaneous defect, contour with or without cutaneous defects and extended contour defects. Options for reconstruction can be divided into local flaps such as cervicofacial rotation flap, pedicled flaps, and free tissue transfers. This chapter provides important considerations and anatomic defect-based approach to the reconstruction of the lateral craniofacial reconstruction.

The aim of the study was to describe the clinical and imaging findings of three dogs diagnosed with orbital ligament avulsion. Three immature dogs presented following a facial bite trauma, including multiple skull fractures and ventral, ventrolateral or rostrolateral displacement of the affected eye. The extent of lesions and orbital ligament avulsion were assessed and diagnosed using CT (n=2) or MRI (n=1). Orbital ligament avulsion was identified as an interruption of the linear structure between the zygomatic process of the frontal bone and the frontal process of the zygomatic bone. One dog was treated surgically to correct a visual axis alteration, while the remaining two dogs were managed conservatively. Orbital ligament avulsion is an uncommon condition that should be considered following a facial trauma. Concurrent lesions might necessitate surgical intervention, but it remains unclear if the avulsion of the orbital ligament itself requires a specific treatment.

Background In order to assess skeletal expansion, alveolar bone bending, and dental tipping after maxillary expansion, linear and angular measurements have been performed utilizing different craniofacial references. Since the expansion with midfacial skeletal expander (MSE) is archial in nature, the aim of this paper is to quantify the differential components of MSE expansion by calculating the fulcrum locations and applying a novel angular measurement system. Methods Thirty-nine subjects with a mean age of 18.2 ± 4.2 years were treated with MSE. Pre- and post-expansion CBCT records were superimposed and compared. The rotational fulcrum of the zygomaticomaxillary complex was identified by localizing the interfrontal distance and modified interfrontal distance. Based on the fulcrum, a novel angular measurement method is presented and compared with a conventional linear method to assess changes of the zygomaticomaxillary complex, dentoalveolar bone, and maxillary first molars. Results From 39 patients, 20 subjects have the rotational fulcrum of the zygomaticomaxillary complex at the most distant points of the interfrontal distance (101.6 ± 4.7 mm) and 19 subjects at the most distant points of the modified interfrontal distance (98.9 ± 5.7 mm). Linear measurements accounted for 60.16% and 56.83% of skeletal expansion, 16.15% and 16.55% of alveolar bone bending, and 23.69% and 26.62% of dental tipping for right and left side. Angular measurements showed 96.58% and 95.44% of skeletal expansion, 0.34% and 0.33% alveolar bone bending, and 3.08% and 4.23% of dental tipping for the right and left sides. The frontozygomatic, frontoalveolar, and frontodental angles were not significant different (P > 0.05). Conclusions In the coronal plane, the center of rotation for the zygomaticomaxillary complex was located at the most external and inferior point of the zygomatic process of the frontal bone or slightly above and parallel to the interfrontal distance. Due to the rotational displacement of the zygomaticomaxillary complex, angular measurements should be a preferred method for assessing the expansion effects, instead of the traditional linear measurement method.

Objective To describe a surgical approach for preplanned orbital exenteration. Animals studied Indications included intraconal orbital mass lesions. Four dogs were included, 3 with neoplasia and one with retro bulbar nodular fasciitis. Procedure To facilitate complete removal of lesions, exenteration was performed by a new procedure for wide access. The frontalis and temporalis muscles were elevated and retracted through a single U-shaped skin incision. Zygomatic arch osteotomy was performed, followed by a 360-degree peritomy and zygomatic process osteotomy. The eyelids were divided from each other through the lateral cantus and then folded forward to expose the globe. The orbit was exenterated by blunt and sharp dissection. Osteotomies were closed with cerclage wires, soft tissues closed and the skin wound sutured in a T-shape. Results The present exenteration procedure gave excellent access to remove orbital contents flush with the optic foramen and orbital fissure. Postoperative swelling and pain were limited and healing uneventful. Two of the 3 neoplasia cases experienced tumor recurrence involving the brain at 18 and 20 months postoperatively, respectively. Both of these had optic canal or intracranial tumor extension preoperatively. Long-term complications included mild concavity of the operated side of the face. Conclusions The present approach for preplanned exenteration offers excellent access for complete removal of orbital contents to the level of the optic foramen. Complications due to the surgical method are few and limited.

This case report demonstrates the use of a 10‐hole 2.7‐mm locking compression plate (LCP) to repair a depressed, comminuted fracture of the zygomatic process of the frontal bone, in a 4‐month‐old Thoroughbred colt foal. Loss of motor function of the right upper eyelid was noted following placement of the LCP and persisted for 5 weeks, the LCP was removed, and intensive medical management of the eye and two temporary tarsorrhaphies were performed over the course of 10 weeks, while motor function very slowly, but gradually improved. The LCP fixation resulted in an excellent cosmetic outcome. Eyelid motor function was almost completely restored 15 weeks after initial trauma to the zygomatic process, avoiding the need for a permanent lateral tarsorrhaphy. This case report demonstrates the excellent cosmetic outcome and healing of a depressed, comminuted fracture in this area. It also suggests that intensive medical management and a prolonged rehabilitation period may be beneficial in cases where cosmetic outcome is a significant factor. Periorbital fractures are common in horses and often associated with trauma. Most minimally displaced fractures of the zygomatic process of the frontal bone heal without fixation. However, displaced fractures may result in ocular injury (corneal ulceration, exophthalmos, globe rupture, blindness etc), nonhealing wounds due to instability or sequestration/infection, and/or poor cosmetic outcome. Surgical reduction and stabilization is often recommended for such cases.1, 2, 3, 4, 5, 6, 7, 8, 9 To the authors’ knowledge, there is no report documenting the use of an LCP in such a location.

Background Pneumatic spaces represent sites of minimal resistance, facilitating the spread of various pathological processes into the joint such as tumors, infection or fractures or vice versa. Considering the clinical importance of temporomandibular joint, prevalence of pneumatic spaces of the temporal bone in relation to TMJ in the roof of the TMJ fossa; articular eminence; zygomatic process and peritubal area was determined using Computed tomography. Laterality and gender wise prevalence of pneumatic spaces around the TMJ was also assessed. Materials and methods A total of 100 high-resolution CT images of adult patients subjected to CT scan for the base of skull/temporal bone were utilized. Axial, reformatted coronal and sagittal images were analyzed on a DICOM viewer for the presence and distribution of pneumatic spaces of the temporal bone around TMJ in the roof of TMJ fossa, articular eminence, zygomatic process and peritubal area. Results The extent of pneumatization of the temporal bone varied considerably. The prevalence of pneumatization of the roof of the TMJ fossa was 52%, articular eminence (12%), the root of the zygomatic process (5%) and peritubal area was 56%. Higher frequency of bilateral pneumatization was seen. No statistically significant correlation was seen in gender wise distribution of pneumatization. Conclusion The present study revealed higher prevalence of pneumatization of temporal bone around TMJ. The knowledge of these air spaces is helpful for the interpretation of imaging studies and to understand the spread of pathological processes into the joint.

Linear marks were observed on the maxillary zygomatic process of the early Pleistocene hominin fossil Stw53 from the Sterkfontein cave site. The taxonomic allocation of this specimen is still under debate, as it has been attributed either to the genusHomoorAustralopithecus. Two alternative hypotheses have been proposed regarding the taphonomic agent responsible for the linear marks observed on this specimen. These modifications were initially assigned to anthropic cutmarks inflicted by stone tools, thus representing the earliest cutmarks discovered on hominin remains. Conversely, these linear marks were interpreted by others as non-anthropic modifications. In order to better understand the origin of the linear marks, a new taphonomic appraisal of these modifications was conducted using a multivariate statistical approach complemented by butchery and trampling experiments on extant mammal bones. This new study of Stw53 linear marks does not provide evidence for anthropic activities but, rather, supports the unintentional origin hypothesis.

Purpose To make a comparative evaluation, by means of the finite element method, of the stress generated on supporting tissues and prosthetic system components, using zygomatic implants with the exteriorized and extramaxillary techniques, and different placement positions, associated either with inclined anterior implants, or those without inclination. Materials and methods Eight (8) tridimensional models were created to represent the clinical situations being researched, using the dataset of scanned images of an edentulous model. The implants and prosthetic components were photographed on millimeter paper and inserted into Rhinoceros 3D modeling computer software. From the measurements made on the image, the virtual models were made. The application force was distributed on the occlusal surface of the working side of the left maxillary first molar, first and second premolars, and incisal regions of the central incisor, simulating the occlusal load during mastication, in a total of 150 N. Results The extramaxillary technique presented considerable variation in increased tension on the prosthesis screws and bone tissue. In the exteriorized technique, the highest tension values occurred in the region of the ridge, and the lowest, on the zygomatic process; the absence of cantilever reduced the stress on bone tissue in almost all regions. Conclusion The exteriorized technique was shown to be more favorable to the distribution of stresses on the micro-unit screws and bone tissue, with the model with zygomatic implant placed in the region of the first molar and inclined anterior implant presenting the best results., Highlights • The extramaxillary technique showed considerable variation in stress increase. • In the exteriorized technique, the highest stress occurred in the alveolar ridge region. • The alveolar bone support for zygomatic implants reduced the internal stress generated by the vertical force.

Pompe disease is a rare neuromuscular disorder characterized by orofacial muscle weakness with consequent dysphagia and poor weight gain. We report the first case of severe trismus due to abnormal elongation of the coronoid process of the mandible in a child with infantile-onset Pompe disease. Bilaterally elongated mandibular coronoid processes cause abnormal impingement between the coronoid process and the zygomatic process, which in this patient, resulted in a maximal interincisal opening of only 6 mm. Although rare, clinicians should be aware of the development of coronoid process elongation in neuromuscular disorders with hypotonia, specifically those involving hypotonic orofacial muscles.

Background Internal maxillary artery (IMax) is a relatively new donor vessel used in the extracranial-intracranial bypass surgery. However, unfamiliarity and relatively elaborate techniques of its harvest precluded its widespread use. Objective To present a simplified technique of IMax harvest based on constant anatomical landmarks without the need of extensive skull-base drilling while providing adequate space for proximal anastomosis. Methods Cadaveric dissection on 4 cadaveric heads (8 sides) was performed. Zygomatic osteotomy was performed and temporal muscle was dissected off the zygomatic process of the frontal bone and the frontal process of the zygomatic bone and reflected inferiorly into the bony gap created by the zygomatic osteotomy. Posterior wall of the maxilla (PWoM) was palpated. Following PWoM inferiorly leads to pterygo-maxillary fissure (PMF), which is a constant landmark IMax passes through. Results IMax was localized following this technique before its entrance into PMF in every specimen. Proximal dissection was carried on to the exposed adequate length of the vessel. Depending on the relationship with the lateral pterygoid muscle, this might need to be incised to allow for identification of the IMax. After its transection, proximal stump is mobilized superiorly into the surgical field. Clinical application of this technique was demonstrated on an aneurysm case. Conclusion Using the palpation of the PWoM as a landmark for localization of PMF facilitates harvesting of IMax without need for extensive skull-base drilling and shortens the time of the surgery.

The locality of Calta has yielded one of the richest collection of fossil canids belonging to the raccoon dog genus NyctereutesTemminck, 1838. This locality is situated in central Anatolia and its age is determined as early Pliocene, c. 4 Ma. Ginsburg (1998) studied these canid remains and identified them as N. donnezani, which was previously known from some early Pliocene localities in southern France and Spain. Some later studies questioned this attribution. The present study provides a new description of all available material, housed in collections in Paris, Lyon and Ankara, and a detailed comparison of the cranial and dental characters with other known species of Nyctereutes. This study is completed by a cladistic analysis of cranial and dental characters to document the phylogenetic relationships of the Calta raccoon dog. This analysis was done on the locality-based data, using the main occurrences of each species. Both morphological and cladistic analyses favour attribution of the Calta raccoon dog to N. donnezani, in agreement with Ginsburg (1998). In addition, this study reveals that possible sexual dimorphism in the size and proportions of some cranial elements, such as stronger sagittal and nuchal crests, a better defined temporal line, a thicker zygomatic process of the maxillary bone, a braincase that is elongated but less round and, in particular, stronger subangular lobe in male individuals.

Made available in DSpace on 2022-04-30T22:00:01Z (GMT). No. of bitstreams: 0 Previous issue date: 2019-06-30 The species of the Ciconiidae family (Ciconiiformes), commonly known as storks, exhibit a cosmopolite distribution, being represented by swamp birds of medium and large size. The present work aimed to describe minutely and comparatively the cranial osteology of Leptoptilus species. The study was performed based on the description of cranial bones of the species Leptoptilus dubius, L. crumeniferus, and L. javanicus. The studied specimens were previously prepared (dry crania and mandibles). Among the studied characteristics, it was possible to observe some structures of systematic importance, such as the zygomatic process, the temporal fossa, the ectethmoid, the superior maxilla, the quadrate bone that interconnects the palate, the neurocranium, and the mandible, performing a key role in the work of cranial kinesis. Leptoptilus javanicus possesses, in the lateral portion of the cranium, an emargination of the rostrodorsal edge of the postorbital process, not observed in either Leptoptilus dubius or Leptoptilus crumeniferus. The fossa ventralis possesses a projection in the caudal extremities in L. dubius and L. crumeniferus, which is absent in L. javanicus. The transpalatine process is present in both L. dubius and L. crumeniferus and is absent in L. javanicus. The pterygoid process of the palatine is short in both L. dubius and L. crumeniferus, and long in L. javanicus. The ectethmoid is reduced in both L. dubius and L. javanicus, whereas in L. crumeniferus, besides being more developed, it presents a U shape. Based on the present study, L. dubius and L. crumeniferus are phylogenetically closer to each other than L. javanicus. Federal University of Piauí São Paulo State University São Paulo State University

The relative position of the zygomatic root to the dentition plays a crucial role in determining the overall strength of the face in response to bite forces. The powerful superficial head of the masseter arises there and the zygomaticoalveolar crest (ZAC) is discussed as a buttressing feature of the face. For instance, a more forwardly or backwardly positioned zygomatic root or a lower or higher vertical distance to the dentition could be indicative for evolutionary adaptations to particular loading regimes which are associated with diet. We therefore examined the morphology of the maxilla using state-of-the-art 3D Geometric Morphometric methods. The data set was reduced to a minimum of relevant measurements and includes five landmarks (pr, ol, zm, lingual and buccal midpoint of second molar alveoli) and three curves with semilandmarks along the lingual and buccal alveolar rim and the ZAC. Results show a stunning overlap in shape variation. We find no clear pattern of shape that would allow separating different hominid groups with confidence, except two extreme forms-Paranthropines and Neanderthals. We also find no clear trend over time. Australopithecines, Habilines, Erectines, and Middle Pleistocene Homo can be very similar to modern humans. Even great apes are within or not far from the central shape distribution of Homo, but they separate clearly from gracile and robust Australopithecines. We discuss the shape factors underlying our data. The geometry studied allows simple measurements and analyses and is thus potentially interesting for classification purposes of extreme forms. Anat Rec, 300:160-170, 2017. © 2016 Wiley Periodicals, Inc.

The human zygomatic structure, consisting of the zygomatic bone and the zygomatic process of the temporal bone, is an essential part of the masticatory apparatus and has been shown to reflect population history and sexual dimorphism to varying degrees. In this study, we analyzed the predictive value of the outlines vs. the complete surface shape of the zygomatic bone in a sample of 98 Chinese (50 ♀, 48 ♂) and 96 Germans (49 ♀, 47 ♂). We first applied a surface registration process based on statistical shape modeling. A dense set of 1,480 pseudo-landmarks was then sampled automatically from the surface of the pooled mean shape and three curves were digitized manually along the outlines of the zygomatic bone. Both sets of pseudo-landmarks were automatically transferred to all specimens. Analysis of sex and population affinity showed both factors to be independently significant, but the interaction between them was not. Population affinity could be predicted quite accurately with correct classification of 97.9% using the surface data and 93.3% with the curve data. Sexual dimorphism was less distinct with 89.2% correct sex determination when using surface information compared with 77.8% when using the curve data. Population-related shape differences were captured primarily in the outlines, while sexual dimorphism is distributed more uniformly throughout the entire surface of the zygomatic structure. Anat Rec, 300:226-237, 2017. © 2016 Wiley Periodicals, Inc.

To elucidate the macroscopical and microscopical structure of dog's lacrimal gland, 15 adult dogs (Canis familiaris) wereutilized in this study. Macroscopically, the lacrimal gland was located on the dorsolateral aspect of the eyeball andbounded dorsolaterally by the orbital ligament, zygomatic process of the frontal bone and frontal process of malar bone.Its shape was nearly rectangular with the average width (1.38 ± 0.13 cm) and length (1.52 ±0.12 cm). In between thedorsal and lateral rectus muscles, the lacrimal artery, vein and nerve were observed. Microscopically, the lacrimal glandwas enveloped by the fibromuscular capsule and lobulated. Each lobule was formed of secretory endpieces and ducts.The secretory endpieces were mucous and serous. However, the mucous type was predominant. The lining cells of thesecretory endpieces expressed a positive reaction to alcian blue and Periodic acid Shiff. A series of duct system withinthe lobules and septa was seen. The scanning electron microscopic examination revealed that the secretory endpiecescovered with granular secretory substance. Several crystals with sharp taper ends were seen around the secretoryendpieces

Reduction malarplasty surgery has become increasingly popular in recent years, especially in many East Asian countries. This is, in part, because many Asians consider a small, smooth, and feminine face to be more attractive and aesthetically desirable. Among the various reduction malarplasty methods, the L-shaped osteotomy technique, through intraoral and sideburn incisions, is now one of the most frequently performed surgical techniques. During the surgical procedure, it is important to shave the zygomatic process of the temporal bone through the sideburn incision. By carrying out this simple adjunctive procedure, several remarkable results can be achieved. The facial width is reduced, especially in those patients with protrusion of the posterior portion of the arch. The outward curvature of the zygomatic arch is changed to point inward. And finally, the bony step that originates from the medial repositioning of the zygomatic arch is reduced, resulting in decreased palpability.

To describe the normal ultrasonographic appearance of the temporomandibular joint (TMJ) in cattle, and to describe the ultrasonographic pathology of the TMJ as assessed in one cow with TMJ disease.The TMJ of 12 healthy Holstein-Friesian cows were examined using a portable ultrasonographic unit with a 7.5 MHz linear probe and a 6.0 MHz convex probe. Each TMJ was scanned in a rostrolateral, lateral and caudolateral plane. In addition, the TMJ of one 2-year-old cow with clinical signs of food retention in the mouth, head tilt, swelling and pain in the right TMJ region and an infected horn fracture was examined ultrasonographically.The bone surfaces of the temporal process, the zygomatic process and the temporal bone, the larger muscles of the TMJ region, the superficial temporal vein, and the parotid salivary gland could be imaged in all normal healthy cattle. Using the linear probe, the joint capsule was visible in 17/24 (71%) cases in the caudolateral plane, but the articular disc could not be visualised. With the convex probe, the joint capsule could be imaged in all cases in the caudolateral plane, and the articular disc in 13/24 (54%) cases in the caudolateral plane. It was never possible to see the synovial pouch in healthy cattle using either probe. By contrast, in the cow diagnosed with septic arthritis of the right TMJ, a marked anechoic and heterogeneous hypoechoic effusion of the TMJ with distension of the joint capsule was visualised.The results of this descriptive study serve to provide a reference for ultrasonography of pathological conditions of the TMJ region in cattle.As many veterinarians are equipped with ultrasound machines with 5-8 MHz linear rectal probes, the authors recommend using these probes for further investigation of clinical cases with swelling of the TMJ region and/or masticatory problems of unclear origin to exclude or diagnose TMJ disorders.

Inioidea, which consists of Iniidae and Pontoporiidae, includes only four extant species, all of which occur in South America. Inioids were, however, more diversified and widely distributed in the past, starting from the late middle Miocene, as recorded from the eastern Pacific, North and South Atlantic, North Sea and the riverine systems of South America. In this paper, the author describes a new extinct inioid, Awadelphis hirayamai gen. et sp. nov. (WU SILS G 408), from the uppermost Miocene Senhata Formation (6.3–5.7 Ma) of Chiba, central Japan. Morphological cladistic analysis supports placement of this new taxon within the Inioidea. The new species is characterized by a right premaxillary eminence with a pronounced overhang on the right maxilla and a short zygomatic process of the squamosal. This is the first fossil record of an inioid not only from Japan but also from the North Pacific. The discovery of this new taxon considerably extends the paleobiogeographic range of inioids, and indica...

Objective The objective of this study is to introduce and describe a surgical technique called Osteoplastic Orbitozygomatic-Mastoid-Transattical Craniotomy (Osteoplastic OZ-MT) and to show the possibility of accomplishing osteoplastic craniotomies for other classical lateral transcranial approaches. Technique The Osteoplastic OZ-MT combines many lateral transcranial approaches. The surgical approach involves structures of lateral and basal portions of the skull, from the frontal bone, superolateral-inferolateral-posterolateral walls of the orbit, zygoma, zygomatic process, sphenoid greater and lesser wings, temporal fossa, mandibular fossa, zygomatic process of the temporal bone, petrous pyramid, mastoid, up to the parietal and occipital regions. The temporal muscle is totally preserved and attached to the one-piece-only bone flap. Results We have developed and used routinely the technique, including its variants and combinations, for about twenty years in children and adults to treat and/or remove mainly mesial, basal, intra, and/or extra-cranium lesions, from the anterior fossa, passing through the middle fossa and going up to the regions of the clivus, basilar artery, and cerebellum-pontine angle, with greater surgical degree of freedom and consequent reduction of morbidity and mortality. So far, we have not had any complications nor important sequels, and the aesthetic and functional results are quite favorable. Conclusion The Osteoplastic OZ-MT is a very systematic, anatomical, feasible, and safe craniotomy. The synthesis is easy to do and can be reopened quickly if necessary. Variants and combinations allow us to opt for a more appropriate approach according to each case.

Understanding of orbital and periorbital anatomy is critical to the diagnosis and therapy of orbital disorders. Twenty-six cat heads were obtained from the dissecting room in the Discipline of Veterinary Sciences, College of Public Health and Veterinary Sciences, James Cook University, Townsville, Australia for use in this study. After macerating the heads and cleaning the skulls they were grouped by morphology into 15 round-headed and 11 flat-headed skulls. In the flat-headed group, the skulls were elongated with a prominent constriction between the cranium and facial bones and a prominent external sagittal crest, which extended from the nuchal crest. Furthermore, complete to nearly complete fusion of the zygomatic process of the frontal bone with the zygomatic arch resulted in a complete bony orbit. The skulls were radiographed, and a total of 32 parameters measured for each group: the skull, cranium, face, orbit and mandible were compared and analyzed. The sites of injecting the infra-orbital, mandibular alveolar and mental nerves were confirmed in both groups of cat skulls. We conclude that old age plays a major role in forming the skull shape (rounded versus flattened) and clo- sure of the orbital rim.