Zygomatic Bone Research Articles

Three-dimensional soft tissue changes after reduction malarplasty in female patients

The aim of this study was to determine the three-dimensional soft tissue changes after reduction malarplasty. Soft tissue changes relative to the amount of movement of the zygomatic bone were studied. Pre- and postoperative cone beam computed tomography images of 21 female patients were superimposed. The anterior-most point of the body osteotomy (point A), arch osteotomy site (point D), and points dividing line A–D into thirds (points B and C) were marked on lateral view images. The vertical distances from the midsagittal line to the centre of the zygomatic bone and the outer prominence of the soft tissue were measured on the coronal view of each image. The proportion of the change in soft tissue to that of the bone before and after surgery was calculated for each point. The relationship between body mass index and the soft tissue change ratio, and the differences in soft tissue changes at each point were analysed. Mean soft tissue changes for points A, B, C, and D were 53.43%, 66.66%, 63.67%, and 57.23%, respectively. The amount of soft tissue change at point B was greater than that at points A and D, which were osteotomy sites. There was no statistical correlation between body mass index and the soft tissue change ratio at each point.

Repair of Enophthalmus in Neglected Tetrapod Zygoma Fracture with Diced Cartilage Graft and Fascia Lata Sling Graft: A Case Report

Introduction: Zygoma fractures with orbital involvement, are the most common midfacial traumas, which cause severe aesthetic and functional sequelae. Late reduction of orbital floor fracture may result in entrapment of orbital soft tissue, predisposing the occurrence of enophthalmos. This article aimed to report enopthalmus correction in neglected tetrapod zygoma fracture case with autologous diced cartilage graft and fascia lata graft.Case Presentation: A 42-year-old female was injured in a traffic accident 8 years ago. Facial fracture was not repaired surgically, resulting in facial asymmetry and diplopia. Physical examination revealed right-sided zygoma deformity, 5mm dystopia, depressed malar eminence, gaze restriction and enophthalmus on the right eye. 3D CT scan confirmed a malunited neglected tetrapod zygoma fracture.Result: Corrective osteotomy was performed to reconstruct the tetrapod zygoma fracture using combination of bicoronal, infracilliary, and maxillary vestibular approach. 4-point fixation and stepladder modification was used. 1.6 cc of cartilage-derived diced bone graft was inserted on the posterior orbital floor to repair enophthalmos. Six months follow-up revealed improved dystopia and malar prominence. Additional surgery was done to repair scleral show and smoothen and augment lower lid volume using 4.5x0.6 cm fascia lata graft hammocked from the medial canthus to lateral orbital bone.Discussion & Conclusion: Long neglected zygoma fracture possessed a difficulty in reconstructing malunited zygoma articulation. Good aesthetic and functional outcome are achievable following use of diced cartilage and fascia lata graft for enophthalmus correction in neglected zygoma-orbital fracture, suggesting the role of fascia lata sling graft for treatment of scleral show and lower lid volume replacement.

Teamwork Approach in Management of Zygomaticomaxillary Complex (ZMC) Fracture with Globe Rupture: A Case Report

Introduction : Zygomaticomaxillary complex (ZMC) fractures are one of the most common fractures of the facial skeleton. Zygomatic fractures can cause ocular and mandibular functional impairment, along with cosmetic defects. The characteristic clinical signs of zygomatic bone fracture include diplopia, infraorbital nerve paraesthesia, flattening of the cheek, and trismus, whereas maxillary fracture may typically cause flattening of the midface and malocclusion. Therefore, surgical reconstruction is required to restore the function and appearance.Case Report : A 31-year-old man with ZMC fracture and globe rupture underwent open reduction and internal fixation using plate and orbital mesh. We collaborated with an ophthalmologist who performed enucleation and tarsorrhaphy.Discussion : The reconstruction improved functional and physical aspects and therefore psychological wellbeing. The main goal of the ZMC fracture treatment is to reconstruct the face in terms of functions and aesthetic. Furthermore, reconstruction of the left orbit (orbital rims and walls) as a secondary objective despite the blind eye, improved his appearance enabling formation of a pocket into which an eye implant was inserted. Satisfying functional and aesthetic outcome was achieved in this patient.Conclusion: A teamwork approach in surgical reconstruction for this case with ZMC fracture which always has an orbital component, was recommended to obtain an effective and optimal result. Both plastic surgeon and ophthalmologist can elaborate patient needs for facial reconstruction especially orbital region with good result.

Oral Mucosal Melanoma: A Case Report and Literature Review

Oral mucosal melanoma is an unusual and aggressive malignant tumor that mainly affects the palate of men aged between 50 and 60 years. We present a literature review focusing on the etiopathogenesis and the clinicopathologic features of this entity. In addition, we reported a rare case of an oral mucosal melanoma arising in the left cheek of a 60-yea r- old man. Computed tomography scan revealed infiltration of the tumor to other anatomic structures including the maxillary sinus, the zygomatic bone and the pterygoid processes. Based on its extension, the lesion was considered inoperable and treatment with three-dimensional conformal radiation therapy was proposed but the patient only attended to the first session and died from cancer progression 6 months after the diagnosis. This paper reinforces the importance of inclusion of this malignant tumor in the differential diagnosis of pigmented lesions of the oral mucosa.

CURRENT INFORMATION ON THE DEVELOPMENT AND FORMATION OF THE STRUCTURE OF SMALL BONES OF THE FACIAL DIVISION OF THE SKULL

The development of the cranial vault bone system is ensured by the sequential development and displacement of various rudiments, which merge, spread and take an indirect part in the formation of the face. The analysis of modern scientifi c literature allows us to come to the conclusion that, despite a number of scientifi c works in human anatomy, the morphogenesis of small bones of the facial skull remains an actual direction of modern medicine. As you know, the small bones of the facial skull include the lacrimal, nasal, zygomatic, palatine bones, the lower nasal concha, which are paired, and the unpaired – the scapula and hyoid bone. Primary ossifi cation of the lacrimal bone appears in the third month of fetal development. Among the anomalies of the nasal conchas, pneumatization, agenesis, and their doubling are quite often detected. The ossifi cation of the ploughshare develops from two connective tissue plates, which fuse together in the process of ossifi cation (beginning in the third month of embryogenesis). Ossifi cation of the nasal bone is determined from one point of ossifi cation, which appears in the third month of embryogenesis. The zygomatic bone undergoes the connective tissue and bone stages of development, the ossifi cation of the nucleus appears in the 8th week of intrauterine development. For a long time, the hyoid bone has been the object of anatomical discussions regarding the peculiarities of its embryonic origin, variants of its structure, position and function. Conclusion. On the basis of the conducted research, it can be stated that in the scientifi c literature there are isolated data on the development and formation of the small bones structure in the perinatal period of ontogenesis of the facial skull. Currently there are no comprehensive studies on the density of bone tissue, morphometric characteristics and correlative relationships of the small bones of the facial skull with the parameters of the face and skull as a whole during the fetal and early neonatal periods of ontogenesis. Last is the basis for determining the morphological prerequisites for the appearance of variants of the facial structure and its congenital defects and determine the need for further anatomical study.

Dynamic navigation for prosthetically driven zygomatic implant placement in extensive maxillary defects: Results of a prospective case series.

Zygomatic implants (ZIs) that are anchored in remote locations can significantly improve the retention and stability of prosthetic obturation in maxillary defect sites without the need for complex surgical reconstruction. However, ZI placement without alveolar bone guidance is challenging, especially when identifying the ideal three-dimensional location of the "coronal part" of the implant fixture for further rehabilitation. To investigate the feasibility and accuracy of surgical navigation for ZI placement using prosthetically driven plans to treat extensive maxillary defects. Software was used to virtually plan the number and distribution of ZIs for maxillary defect patients according to the existing residual maxillofacial bone. The "coronal part" of the ZI was identified based on the existing maxillodental prosthetic flange, virtually planned infrastructure framework and superstructure. ZI placement was fully guided by surgical navigation. Ten patients were enrolled. One patient had loose reflective spheres, which resulted in an inaccurate back-reflection of the position during navigation. A total of 27 ZIs in the remaining 9 patients were placed uneventfully. The mean of the "coronal part" of the ZI, entry point of the zygomatic bone, apical deviation, and apical angle deviation were 1.50 mm, 1.39 mm, 1.95 mm, and 2.32°, respectively. A Computer-aided design and computer-aided manufacture milled bar and additional attachments were fabricated according to preoperative planning. No osseointegrated implant loss was detected. Six ZIs in three patients received implant surface polishing to reduce soft tissue irritation, and one ZI was submerged. Surgical navigation facilitated the accurate and feasible placement of prosthetically driven ZIs that were preoperatively planned in patients with extensive maxillary defects.

Skin landmarks to main cerebral structures: how to identify the main cerebral sulci? A radiological study about lateral, central, and parietooccipital sulci.

In a previous cadaveric work, we identified and described useful and reproducible surface skin landmarks to lateral sulcus, central sulcus and preoccipital notch. Potential limitations of this cadaveric study have been raised. Thus, the objective of this study was to confirm radiologically the accuracy of these previously described surface skin landmarks on brain magnetic resonance imaging (MRI) of healthy subjects. Healthy adult volunteers underwent a high-resolution brain MRI and measurements of the orthogonal skin projection (OSP) of the anterior sylvian point (AsyP), the superior Rolandic point (SroP) and the parietooccipital sulcus were made from nasion, zygomatic bone and inion, respectively. These measures were compared to our previous cadaveric findings. Thirty-one healthy volunteers were included. ASyP was 33 ± 2mm above the zygomatic arch, and 32.3 ± 3mm behind the orbital rim. The lateral sulcus was 63.5 ± 4mm above the tragus. The SRoP was 196.9 ± 6mm behind the nasion. The superior point of the parietooccipital sulcus was 76.0 ± 4mm above the inion. These measurements are comparable to our previously described cadaveric findings. We here described three useful, simple and reproducible surface skin landmarks to lateral, central and parietooccipital sulci. Knowledge of these major landmarks is mandatory for Neurosurgical practice, especially in an emergency setting.

Analysis of aging-related changes in the lower eyelid tissue structure in Han Chinese women

To analyze aging-related regional changes in the lower eyelid tissue structure of Han Chinese women as data reference and theoretical basis for rejuvenation treatment of lower eyelids. Magnetic resonance imaging (MRI) data of healthy Han Chinese women with a body mass index (BMI) between 18.5-23.9kg/m2 were collected and stratified by age. MRI of the mid-sagittal plane of the eyeball was analyzed. The orbital margin was marked as the coordinate O point while the surface of the zygomatic bone was marked as the coordinate y-axis. The vertical line between the O point and y-axis was marked as the x-axis. The position of each point of the orbicularis oculi muscle contour and the subcutaneous fat tissue contour on the coordinate axis was measured. The thickness and contour morphology of the subcutaneous fat and orbicularis oculi muscle at different positions were calculated according to the coordinate position of each point. Age-related changes in the structure, contour, and position of the subcutaneous tissue in the lower eyelid area were analyzed. With aging, the thickness of the orbicularis oculi muscle decreased while its width increased. Notably, the radian of the orbicularis oculi muscle in the tarsal portion protruding to the skin increased. The subcutaneous fat of the orbital margin thinned while the subcutaneous fat below the orbital margin thickened with age. The subcutaneous tissue structure of the lower eyelid region in Han Chinese women showed regular changes during aging, chiefly characterized by the widening and thinning of the orbicularis oculi muscle, and the gradual shifting of the subcutaneous fat to the middle and lower regions.

The Cognitive Load of Learning Anatomy in a Virtual World

IntroductionCognitive load refers to the amount of working memory that is being used in a task, like memorizing the anatomical landmarks on distinct boney specimens. Critically, cognitive load may be compromised when the load imposed by the environment and the content to be learned together exceeds a student’s capacity. Previous research shows that stereoscopic materials delivered in virtual reality (VR) can be more mentally taxing compared to desktop (i.e., two dimensional) delivery but may be similar to that encountered in real life. There is no data on the cognitive load of autostereoscopic displays. Given the increased reliance upon digital media for teaching in learning in anatomy classrooms, it is prudent to better understand the cognitive load imposed on learners across a variety of modalities employed.MethodsCognitive load will be compared across three different learning modalities: immersive virtual reality (VR, displayed on the Oculus Quest 2TM), autostereoscopic (displayed on the AlioscopyTM screen), and an identical printed, physical model. During a four‐minute learning phase, undergraduate students, with no prior formal anatomy education, will learn 10 anatomical landmarks on a displayed bony model (calcaneus, zygomatic bone, or hemipelvis) in each of the three modalities. A Stroop test will be administered as a secondary task throughout the learning phase to evaluate cognitive load. Stroop test reaction time, and accuracy of the participants' responses to the Stroop test will be recorded. After the learning phase, an untimed, recognition‐based test will be administered wherein participants will be asked to recall the ten landmarks learned with the aid of a 3D‐printed bone identical to the one used in the learning phase. Performance will be evaluated based on landmarks correctly identified and the results will be correlated with cognitive load measured in each learning modality.ResultsWe hypothesize that the cognitive load will be highest for VR when compared to the cognitive load on the AlioscopyTM and physical model modalities which would manifest as lower reaction times and/or accuracy on the Stroop test. Further, we hypothesize that cognitive load will inversely correlate with the recognition test performance.ConclusionThe results of this study will allow educators and students to make informed decisions when deciding which learning modalities should be used for anatomy education or any other education that requires nominative learning on complex objects. Understanding which modalities minimize cognitive load and improve learning will help improve outcomes and allow for more efficient anatomical education.

Virtual Reality, Autostereoscopy, and Physical Models for Learning Anatomy: Performance Comparisons

IntroductionTraditional anatomical education relies on textbooks, physical models, and cadaveric specimens. Advances in technology have provided other display modalities including virtual reality (VR), and autostereoscopic displays. VR uses head‐mounted displays (HMDs) for an interactive experience and autostereoscopic screens, like AlioscopyTM, offer a stereoscopic but HMD‐free environment. Current research shows contradictory results on the efficacy of VR compared to physical models, and there appears to be no data on the efficacy of autostereoscopic displays in learning anatomy. The purpose of this study is to determine whether VR, AlioscopyTM, or physical models yield the best performance for anatomical education.MethodsStudents at McMaster University without prior anatomy training will learn nominal skeletal anatomy in three different modalities: VR (Oculus Quest 2TM), AlioscopyTM, or a physical 3D‐printed bone model. Each of the environments will be as identical as possible (i.e, the VR environment is a rendering of the exact room and set‐up used for testing the physical bone models). Participants will be randomized to one of three interventions where they will study ten bony landmarks on either the human hemipelvis, zygomatic bone, or calcaneus in a distinct modality. Participants will be seated and use an XboxTM controller to rotate the bone along the vertical axis of rotation. After four minutes, an untimed, recognition‐based test will be administered, where participants will be given a 3D‐printed bone identical to the one used in the learning phase, with randomized landmarks and word bank of landmarks learnt. Performance will be evaluated based on landmarks correctly identified on the recognition‐based test.ResultsBased on the current literature, we hypothesize that the physical models will be a superior learning environment compared to the VR environment. However, significant improvements in the HMD of the Oculus Quest 2 may have ameliorated previous issues with the VR environment. There is no data available on the efficacy of AlioscopyTM and while the absence of an HMD is appealing, its narrow viewing angle compared to the immersive VR environment may be problematic.ConclusionWith the push to increase accessibility and decrease costs associated with anatomical education with the help of digital modalities, the findings from this study are critical to informing teaching practices, and technology use in anatomy education.

Evaluating Cybersickness in Virtual 3D Models for Anatomy Learning

IntroductionCybersickness is an array of symptoms associated with exposure to three‐dimensional visualization technology (3DVT) environments, such as virtual reality (VR). It is thought that cybersickness is a type of motion sickness caused by a mismatch in sensory and vestibular input when using these modalities. Symptoms of cybersickness are often akin to those of traditional motion sickness, such as headache and nausea. In the literature, as many as 40‐60% of VR users report symptoms of cybersickness, though in our laboratory approximately 20% of users report symptoms of cybersickness. Our past research has shown that the physical environment is often preferred by students, and more effective for learning anatomy, compared to 3DVT environments. We hypothesize that the preference for, and effectiveness of, the physical environment over 3DVT may be a result of cybersickness due to the isolation of the learner from the physical environment. However, no direct measurements of cybersickness or comparisons between 3DVT environments in anatomy are available.MethodsOur study involves comparisons of cybersickness during anatomy learning between three 3D modalities: a VR Oculus Quest 2TM headset, an autostereoscopic screen (AlioscopyTM), and a 3D‐printed physical model. Undergraduate students, with no formal anatomy training, will be randomized via a Latin square design to view one of three skeletal models (human hemipelvis, zygomatic bone, or calcaneus) in each of the modalities. Participants may not touch the model but may rotate it along the horizontal plane using an XboxTM controller. Participants will have four minutes to learn ten bony landmarks on the viewed model and will then take an untimed, recognition‐based test for landmarks learned before progressing onto the next modality. Cybersickness will be assessed following testing in each modality, via self‐reports on the simulation sickness questionnaire (SSQ).ResultsWe hypothesise that reported cybersickness will be highest for the VR displayed on the head‐mounted display of the Oculus Quest 2TM which entirely covers the visual field, compared to learning through the AlioscopyTM screen or the physical model due to the relative lack of isolation of the learner from the physical environment in the last two treatment groups.ConclusionWith the rapid development of 3DVT for use in anatomical education, cybersickness is an important issue in evaluating the quality of 3D modalities. The results of this study will allow educators and students to make informed decisions about the use of 3DVT in anatomy thus preventing uncomfortable physical symptoms associated with learning using 3DVT and improving learning as a result.

Comparison of Extramaxillary Anchored Implants, Tilted Implants, or Sinus Elevation Concepts on Stress Distribution in Atrophic Maxilla: A Finite Element Analysis.

To determine the von Mises stress values of extramaxillary implants anchored in zygomatic bone, known as zygomatic implants, abutments, superstructures, and principal stress values of bone under occlusal forces and to compare them with tilted implants and sinus elevation concepts. The hypothesis of the study was that there would be higher stress on zygomatic implants under occlusal forces compared with tilted implants and the sinus elevation technique due to the more angled placement of the zygomatic implants. Finite element analysis (FEA) was used to apply a force of 600 N (75 N premolars and 150 N first molar) vertically and at an angle of 20 degrees to the hybrid prosthesis with three different concepts-zygomatic implants, tilted implants, and sinus elevation-in D2 bones in six separate models. The posterior implants were tilted in zygomatic implant models (45 degrees) and tilted implant models (30 degrees). The von Mises and principal stress values formed in the models were compared by FEA. These values were also compared with the physiologic stress limit of the bone. In the zygomatic implant models, the von Mises stress values on both anterior and posterior implants were less than other models under both loading conditions. In addition, the lowest principal stress values were seen in these models. The highest von Mises stress among all models was found to be posterior implants in tilted implant models under oblique loading. In addition, the highest principal stress values were seen at posterior implants in the sinus elevation model under oblique loading. Vertical loading was found to induce less stress than loading at a 30-degree angle. Although zygomatic implants have a more angled placement, the stress values on the bone and implants are lower.

The Correction of Plagiocephaly

Real Plagiocephaly is a rare form of craniosynostosis, resulting from the premature fusion of the coronal suture on one side, leading to a deformed head and to an apparently exteriorized homolateral eye. We present a simple and straightforward technique, based on removal of the involved suture, with the surgical incision prolonged to the orbital roof till near the ethmoide. After having sectioned the lateral border of the orbit at the junction of the zygomatic and frontal bones, a paramedian incision is made on the frontal bone, from the anterior fontanel (always carefully preserved), till the glabella. Then follows simple osteoclasia of the frontal bone and placement of a bone graft obtained from the adjacent parietal bone and that will maintain the forward projection of the frontal bone (but in slight hypercorrection). The grafts are simply fixed with silk sutures, placed through perforating holes in the bones, no metal being used. The transverse surgical wound, going almost from ear to ear, is closed in the usual way.

Severe Self-Inflicted Gunshot Wound of the Face

A 26-year-old male was transported to the hospital with a severe self-inflicted gunshot wound of the middle and lower face (Panel A) due to the suicide attempt. Three-dimensional computed tomography (CT) showed multiple site comminuted fracture of the facial skeleton including maxilla, mandible, right zygomatic, ethmoid, and nasal bones (Panel B). Also, the sockets of multiple avulsed teeth were noted. The patient was transported from the region several days after the injury. Due to the osseous and soft tissue loss, this type of gunshot wounds typically poses a considerable challenge to the oral and maxillofacial and plastic surgeons. Acute management in such cases includes resuscitative and life-saving measures. Timing of each surgical procedure should be chosen according to the patient condition, extent of the injury, and international recommendations.1 Operative principles include: (1) general considerations (all reconstructive options are to be taking into account, moreover, the volume of bone and soft tissue loss, functional and aesthetic purposes should be analyzed and planned very precisely), (2) skeletal fixation, (3) bone grafts, (4) soft tissue coverage, and even (5) a facial transplantation in some cases. In our case, the right eye enucleation (removal of the entire globe with all intraocular contents, while preserving orbital/periorbital structures) was done due to the severely ruptured globe. Typical indications for enucleation are severe eye trauma and blind, intraocular tumors, painful, and cosmetically disfiguring eyes. In case of evisceration the intraocular contents are removed from an intact sclera, extraocular muscle attachments and the orbital adnexa are preserved, with placement of an implant within the scleral shell with a purpose to retain orbital volume. Common indications for enucleation are unresponsive endophthalmitis and for improvement of cosmesis in a blind eye. The most common indication for orbital exenteration (removal of the globe and all orbital contents, including muscles, fat, optic nerve, lacrimal gland, nerves, periorbital bone, upper and lower lid complexes) is malignancy.

Volumetric and linear assessment of maxillary, mandibular and zygomatic bone as donor sites for alveolar ridge augmentation using CBCT

Objective: To analyze preoperative CBCT assessment of intraoral donor sites (symphysis, ramus buccal shelf of bone, zygomatic buttress and maxillary tuberosity) for purpose of autogenous block graft. Materials and Methods: Twenty (5 for each graft) participants were included in the study, (informed consent was signed by each participant) Participants were recruited according to certain eligibility criteria. Results: The measurements of the block grafts showed that there was a significant difference between different sites (p<0.001). The highest value was found in mandibular symphysis (1.56±0.44), followed by mandibular ramus (0.99±0.19), then zygomatic buttress (0.49±0.06), while the lowest value was found in maxillary tuberosity (0.31±0.07). Post hoc pairwise comparisons showed value of mandibular symphysis to be significantly higher than other sites (p<0.05). In addition, they showed mandibular ramus value to be significantly higher than values of zygomatic buttress and maxillary tuberosity (p<0.05). Conclusion: According to this study, mandibular donor sites showed larger segmented pieces and larger volumes than their maxillary counterparts. For multiple missing teeth, the most appropriate block grafts will be the symphysis and ramus spanning the largest mesio-distal dimension. In terms of implant stability, the rami and maxillary tuberosities showed the largest thicknesses, which will ultimately help in implant stability.

Periorbital infection and fistula after placement of zygomatic implants: a case report and review

Zygomatic implants are a good alternative to severely atrophic maxilla prosthetic treatment, but complications can result from their placement. Skin fistulas are extremely rare complications of zygomatic implants, but it’s management can be challenging. Skin complications can happen when the apex of the zygomatic implant protrudes above the limits of zygomatic bone. To prevent its occurrence, careful planning must be done. The surgeon must control the final position of the implant at the appropriate length carefully. If infection or cutaneous fistula occurs, surgery to cut off the apex of the implant is indicated, either intra- or extra-orally. The aim of this case report was to describe the case of cutaneous fistula after Quad Zygoma treatment of extreme maxillary bone atrophy. A 56-year-old woman developed a left periorbital fistula 4 months after the placement of 4 zygomatic implants. Implant apex was palpable under the skin of zygomatic bone body. We opted for extra-orally cut off the implant tip above the outer cortical of the zygomatic bone. Postoperative course was uneventful and the patient had no more signs and symptoms of infection or fistula.

A facial ulcer secondary to a non-invasive ventilation mask in COVID-19 pneumonia

Sir, An 83-year-old patient hospitalized in the intensive care unit (ICU) of the pulmonary department for chronic respiratory failure complicated by severe COVID-19 pneumonia with respiratory involvement of 50% of the lungs. The comorbidities included diabetes, uncontrolled hypertension, ischemic heart disease, Parkinson’s disease, and bronchial asthma. The patient was unable to maintain adequate arterial oxygen saturation with a face mask and nasal prongs. The attending physician ordered non-invasive ventilation (NIV) and a continuous positive airway pressure (CPAP) mask was applied. On day ten of the patient’s ICU stay, his attending physician noticed a grade II cheekbone ulcer. The patient was put on a paraffin dressing. The evolution was marked five days later by a worsening in the stage of the pressure ulcer, which had become a stage III ulcer and, therefore, our opinion was requested. An examination of the patient revealed a well-adjusted, full-face mask with pressure against the zygomatic bone aggravated by the application of compresses, which further increased the aggression against the bone. A dermatological examination found two necrotic patches on both cheekbones without a peripheral detachment or inflammatory border (Fig. 1). There were no signs of bacterial infection. Upon investigation, the caregivers revealed that the CPAP mask had been left in place for nearly eighteen hours daily without formal monitoring or the inspection of the pressure areas. Fortunately, the patient’s condition began to improve as did her arterial oxygen saturation. The pulmonologist was gradually attempting to remove the patient from NIV. Strict monitoring of the pressure points was recommended and the patient was put on a hydrogel dressing for five days until the necrosis was eliminated, then on a hydrocolloid dressing after the mechanical removal of the remnants of the necrosis and fibrin with good improvement of the ulcer. The COVID-19 epidemic represents a new challenge for critical care physicians (ICU). In the context of this epidemic, the management of arterial oxygenation during critical care procedures is one of the main challenges for ICU physicians. As an effective means of ensuring satisfactory arterial oxygenation during COVID-19 pneumonia, more than 50% of patients treated in China required non-invasive ventilation (NIV) [1]. During NIV with headgear, ICU nurses should focus on interventions that help to improve the patient’s comfort to maximize the acceptability of the device and minimize mask-induced skin irritability [1]. Skin pressure sores secondary to helmet application may be prevented by applying hydrocolloid dressings associated with close monitoring of the patient’s tolerance to the pressure exerted by the mask [2]. The development of NIV-related pressure sores is due to a combination of pressure effects and shear forces exerted by the presence of a mask, pressure changes during the different phases of ventilation, and the tension of the mask’s strap [3]. The use of oronasal masks and increased time on NIV increases the risk of pressure ulcer formation, as do patient factors such as age, sensory impairment, chronic skin conditions, and hypotension [4]. Oronasal masks remain the most popular interface, with a European survey revealing that they are the first choice in 70% of cases. The reasons given by respondents for their choice were the reduction of air leakage, patient comfort, and cost [5].

The effects of 3-D Screw on the nasomaxillary complex in skeletal class III malocclusion

Aim of the study is to evaluate the Stress distribution and displacement of various structures of nasomaxillary complex with 3- D screw in skeletal class III malocclusion. An analytical model was developed from a human skull of a 15-year-old male. CT scan images of the skull were taken in axial direction parallel to the F-H plane, which was processed using Mimics software, required portion of the skull & 3-D screw appliance was converted into geometric model using reverse engineering technique. ANSYS software was used to solve the mathematical equation. Contour plots of the displacement and stresses were obtained from the results of the analysis performed. Maximum transverse displacement was 3.18mm at the permanent first maxillary teeth. Maximum antero-posterior displacement was 1.26mm at the anterior part of zygomatic bone and 1.35mm of displacement frontozygomatic suture. maximum vertical displacement was 2.81 mm representing the inferior and medial portion of the nasal bone and indicating downward displacement. Pyramidal displacement of maxilla was evident. Apex of pyramid faced towards nasal bone and base was located on the oral side. There was downward, forward movement of maxilla with a tendency toward posterior rotation. Maximum von Mises stresses were found along midpalatal, zygomaticomaxillary, nasomaxillary, frontozygomatic sutures.

Pattern of Maxillofacial Injuries in Road traffic Accident During Covid-19

Objectives: This study aims to assess the prevalence and pattern of maxillofacial injuries presented at department of oral & maxillofacial surgery (OMFS), Mayo Hospital, Lahore, Pakistan during COVID- 19 pandemic. Determining patterns of occurrence of maxillofacial trauma and etiology can improve early diagnosis and treatment, thereby can decrease percentage of morbidity and mortality associated with these fractures. Place and duration; Sample data was collected from Department of OMFS, Mayo hospital, during January 2021 till December 2021. Methodology: (n=263) patients with confirmed diagnosis of maxillofacial trauma participated in this research. Record of all patients including sex, age, cause of road traffic accidents, radiograph, fracture site, vehicle type, use of seat belts/helmets, time to reach the hospital, and other safety devices were reviewed and evaluated. Results: There were (n=299, 57.27%) mandibular, (n=102, 19.50 %) zygomatic, (n=100, 19.10 %) maxillary, (n=12, 2.29 %) nasal, and (n=9, 1.70 %) frontal injuries. Maxillofacial trauma was more prevalent in males (87%) than in females (13%) and was commonly seen in young age groups (21-30 years). Two-wheelers (motorcycle) was the vehicle used in most of the cases reported (68.4 %) and major cause of RTA was inattentiveness to traffic rules (31.9 %). In road traffic accidents, mandible (57.27%) is the most common fractured bone, followed by Zygomatic Bone fracture. Conclusion: It is concluded that maxillofacial injuries in males (20 to 30 years) of age range were more prevalent and are observed mostly in mandibular bones. Although cases reported was less in number when compared to previous data, but pattern of fractured facial bones were more or less same.

Enhanced facial esthetics for geriatric patients with customized complete denture for amplified cheek support

Aging is associated with edentulism, resorbed alveolar ridge, reduced muscle activity, and sunken cheeks. When there is not enough muscle mass between zygomatic and mandibular bone, slumping of cheeks occurs. Sunken cheeks lead to facial disfigurement and unesthetic appearance resulting in a negative psychological impact on the patient. The use of conventional complete dentures can rehabilitate the loss to some extent, but excellent denture esthetics can be achieved by providing additional support to the slumped tissues. This clinical case series describes different techniques to provide support for sunken cheeks using detachable maxillary cheek plumper prosthesis in completely edentulous geriatric patients.