Developmental origin of the mammalian premaxilla.

The evolution of jaws has played a major role in the success of vertebrate expansion into a wide variety of ecological niches. A fundamental, yet unresolved, question in craniofacial biology is about the origin of the premaxilla, the most distal bone present in the upper jaw of all amniotes. Recent reports have suggested that the mammalian premaxilla is derived from embryonic maxillary prominences rather than the frontonasal ectomesenchyme as previously shown in studies of chicken embryos. However, whether mammalian embryonic frontonasal ectomesenchyme contributes to the premaxillary bone has not been investigated and a tool to trace the contributions of the frontonasal ectomesenchyme to facial structures in mammals is lacking. The expression of the Alx3 gene is activated highly specifically in the frontonasal ectomesenchyme, but not in the maxillary mesenchyme, from the beginning of facial morphogenesis in mice. Here, we report the generation and characterization of a novel Alx3CreERT2 knock-in mouse line that express tamoxifen-inducible Cre DNA recombinase from the Alx3 locus. Tamoxifen treatment of Alx3CreERT2/+;Rosa26mTmG/+ embryos at E7.5, E8.5, E9.5, and E10.5, each induced specific labeling of the embryonic medial nasal and lateral nasal mesenchyme but not the maxillary mesenchyme. Lineage tracing of Alx3CreERT2-labeled frontonasal mesenchyme from E9.5 to E16.5 clearly showed that the frontonasal mesenchyme cells give rise to the osteoblasts generating the premaxillary bone. Furthermore, we characterize a Dlx1-Cre BAC transgenic mouse line that expresses Cre activity in the embryonic maxillary but not the frontonasal mesenchyme and show that the Dlx1-Cre labeled embryonic maxillary mesenchyme cells contribute to the maxillary bone as well as the soft tissues lateral to both the premaxillary and maxillary bones but not to the premaxillary bone. These results clearly demonstrate the developmental origin of the premaxillary bone from embryonic frontonasal ectomesenchyme cells in mice and confirm the evolutionary homology of the premaxilla across amniotes.

Ciliary and non-ciliary functions of Rab34 during craniofacial bone development.

The primary cilium is a hair-like projection that controls cell development and tissue homeostasis. Although accumulated studies identify the molecular link between cilia and cilia-related diseases, the underlying etiology of ciliopathies has not been fully understood. In this paper, we determine the function of Rab34, a small GTPase, as a key regulator for controlling ciliogenesis and type I collagen trafficking in craniofacial development. Mechanistically, Rab34 is required to form cilia that control osteogenic proliferation, survival, and differentiation via cilia-mediated Hedgehog signaling. In addition, Rab34 is indispensable for regulating type I collagen trafficking from the ER to the Golgi. These results demonstrate that Rab34 has both ciliary and non-ciliary functions to regulate osteogenesis. Our study highlights the critical function of Rab34, which may contribute to understanding the novel etiology of ciliopathies that are associated with the dysfunction of RAB34 in humans.

Insights into Craniofacial Development and Anomalies: Exploring Fgf Signaling in Zebrafish Models.

PURPOSE OF REVIEW: To illustrate the value of using zebrafish to understand the role of the Fgf signaling pathway during craniofacial skeletal development under normal and pathological conditions. RECENT FINDINGS: Recent data obtained from studies on zebrafish have demonstrated the genetic redundancy of Fgf signaling pathway and have identified new molecular partners of this signaling during the early stages of craniofacial skeletal development. Studies on zebrafish models demonstrate the involvement of the Fgf signaling pathway at every stage of craniofacial development. They particularly emphasize the central role of Fgf signaling pathway during the early stages of the development, which significantly impacts the formation of the various structures making up the craniofacial skeleton. This partly explains the craniofacial abnormalities observed in disorders associated with FGF signaling. Future research efforts should focus on investigating zebrafish Fgf signaling during more advanced stages, notably by establishing zebrafish models expressing mutations responsible for diseases such as craniosynostoses.

Nanomaterial-integrated injectable hydrogels for craniofacial bone reconstruction.

The complex anatomy and biology of craniofacial bones pose difficulties in their effective and precise reconstruction. Injectable hydrogels (IHs) with water-swollen networks are emerging as a shape-adaptive alternative for noninvasively rebuilding craniofacial bones. The advent of versatile nanomaterials (NMs) customizes IHs with strengthened mechanical properties and therapeutically favorable performance, presenting excellent contenders over traditional substitutes. Structurally, NM-reinforced IHs are energy dissipative and covalently crosslinked, providing the mechanics necessary to support craniofacial structures and physiological functions. Biofunctionally, incorporating unique NMs into IH expands a plethora of biological activities, including immunomodulatory, osteogenic, angiogenic, and antibacterial effects, further favoring controllable dynamic tissue regeneration. Mechanistically, NM-engineered IHs optimize the physical traits to direct cell responses, regulate intracellular signaling pathways, and control the release of biomolecules, collectively bestowing structure-induced features and multifunctionality. By encompassing state-of-the-art advances in NM-integrated IHs, this review offers a foundation for future clinical translation of craniofacial bone reconstruction.

Evaluation of Facial Aging in Different Age and Gender Groups With Computed Tomography-Based Calvarium and Face Measurements.

BACKGROUND: The human face is a complex area formed by the combination of many different components and varies among individuals according to gender, age, and ethnicity. OBJECTIVE: The aim of this study was to evaluate age-related changes in the facial and calvarial bones in a large sample of both genders. METHODS: The retrospective study included nontraumatic brain computed tomography scans of 280 Turkish adults. Participants were divided into 7-decade groups with the age ranging from 20 to 89 years. Measurements of the face and calvaria were recorded, and calvarial volume was calculated. The relationship of these parameters with age and gender was examined. RESULTS: Statistically significant differences were observed in all the facial and calvarial measurements, except the transverse diameter of the head, with increasing age in both genders. Regardless of age, no significant differences were found in facial and calvarial measurements between genders. In addition, there was a significant decrease in the calvarial volume in both genders after the seventh decade of life. CONCLUSION: The structure of the face and calvarium continues to change and differentiate throughout life. Taking these changes into account during surgical and facial rejuvenation procedures can help predict outcomes and avoid the use of incorrect techniques.

Biparietal remodelling and total vault remodelling in scaphocephaly-a comparative study using 3d stereophotogrammetry.

PURPOSE: The aim of the study was to compare the results of two surgical techniques for the treatment of isolated sagittal synostosis (ISS) by means of 3D stereophotogrammetry. One technique, the Renier's "H" technique (RHT) comprised a biparietal expansion, the other, the total vault remodeling (TVR) included also a frontal remodeling. METHODS: The two groups of operated children were compared with a third control group of normocephalic children. The 3D scanning was performed in all children between 12 and 245 months of age. On each 3D image six measurements and indices have been made, with the aim of evaluating not only length and width of the head, but also the height. The cranial index (CI) was measured in a plane parallel to the nasion-tragus plane, at the intersection with the opisthocranion. RESULTS: Each of the three groups (RHT, TVR, control group) included 28 children. The measurements that were influenced by the correction of the frontal bossing, namely the CI and the sagittal length, were closer to normocephaly after TVR than after RHT. Lesser or no statistical difference was documented in the measurements evaluating the biparietal aspect and the height of the vertex, indicating that the biparietal expansion is effective in both procedures. CONCLUSION: Based on our results TVR results in a better esthetical outcome, particularly in relation to the direct surgical remodeling of the frontal bossing.

Epidemiology of Craniomaxillofacial Fractures Over a 5-year Period at a Midwestern Level 1 Trauma Center Serving a Large Rural Population.

BACKGROUND: Though the epidemiology of craniomaxillofacial (CMF) fractures has been well documented at urban hospitals, the characteristics of these fractures in rural hospitals have not been well studied. PURPOSE: The purpose of this study is to report on the epidemiology of CMF fractures at a regional Level 1 trauma center serving a large rural population in central Illinois. STUDY DESIGN, SETTING, SAMPLE: This is a retrospective cohort study at a community-based regional tertiary referral center that serves a predominantly rural population. Inclusion criteria comprised patients with radiologically confirmed CMF fractures between 2015 and 2019. Patients with incomplete medical records were excluded. PREDICTOR VARIABLE: Predictor variables included demographics (age, admission source, race, and sex) and etiology of CMF fracture (assault/domestic violence, all-terrain vehicle/off-road, falls, farm-related, motor vehicle collisions, gunshot wound, and others). MAIN OUTCOME VARIABLE: The primary outcome variable was the CMF anatomic location including nasal bone, orbit, mandible, malar/maxillary, and other CMF fractures. COVARIATES: The covariates are not applicable. ANALYSES: Descriptive statistics were used to summarize a sample of the population characteristics. Wilcoxon ranked sign tests and χ2 tests of independence were used to assess for statistically significant associations between select variables of interest. Statistical significance was defined as P < .05. RESULTS: Between 2015 and 2019, a total of 2,334 patients presented to the emergency department with a CMF fracture. After applying the inclusion/exclusion criteria, the final sample was composed of 1,844 patients for the management of 2,405 CMF fractures. The majority of patients were male(62.0%) and young adults (aged 18-39) had the highest number of CMF fractures (819) relative to all other age groups. The most common fracture etiology was fall(37.3%), and nasal bone fractures represented the most common fracture location(41.6%). χ2 analyses revealed statistically significant associations between the anatomic location of CMF fracture incurred, and differing categories of age, admission source, race, sex, and etiology. CONCLUSION AND RELEVANCE: Our study shows that patients seen at our Midwestern Level 1 trauma center are more likely to present with nasal bone and malar/maxillary fractures due to falls. In studies based in urban centers, patients are likely to present with orbital and mandibular fractures due to falls and assault.

Mammalian face as an evolutionary novelty.

The anterior end of the mammalian face is characteristically composed of a semimotile nose, not the upper jaw as in other tetrapods. Thus, the therian nose is covered ventrolaterally by the "premaxilla," and the osteocranium possesses only a single nasal aperture because of the absence of medial bony elements. This stands in contrast to those in other tetrapods in whom the premaxilla covers the rostral terminus of the snout, providing a key to understanding the evolution of the mammalian face. Here, we show that the premaxilla in therian mammals (placentals and marsupials) is not entirely homologous to those in other amniotes; the therian premaxilla is a composite of the septomaxilla and the palatine remnant of the premaxilla of nontherian amniotes (including monotremes). By comparing topographical relationships of craniofacial primordia and nerve supplies in various tetrapod embryos, we found that the therian premaxilla is predominantly of the maxillary prominence origin and associated with mandibular arch. The rostral-most part of the upper jaw in nonmammalian tetrapods corresponds to the motile nose in therian mammals. During development, experimental inhibition of primordial growth demonstrated that the entire mammalian upper jaw mostly originates from the maxillary prominence, unlike other amniotes. Consistently, cell lineage tracing in transgenic mice revealed a mammalian-specific rostral growth of the maxillary prominence. We conclude that the mammalian-specific face, the muzzle, is an evolutionary novelty obtained by overriding ancestral developmental constraints to establish a novel topographical framework in craniofacial mesenchyme.

Time-to-operation delays and in-hospital complications in operative facial trauma: A national analysis.

BACKGROUND: Management of facial fractures is variable. Understanding how time to operative management impacts outcomes can help standardize practice. METHODS: Retrospective analysis of the ACS Trauma Quality Improvement Program (TQIP) database between 2016 and 2019. Adult patients with operative facial fractures were isolated by ICD-10 procedure codes, and further stratified by fracture location, including the mandible, orbit, maxilla, zygoma, and frontal bone. Multivariable logistic regression was conducted to predict in-hospital complications (both surgical and systemic complications) adjusting for time-to-operation, comorbidities, fracture location, AIS, and demographics. RESULTS: 1678 patients with operative facial fractures were identified. The median time-to-operation was 2 days (IQR 1.0-2.0 days). Most patients only had one operative fracture (95 %) and orbital fracture was the most common (44 %). The overall complication rate was higher for those operated after 2 days compared to those operated between 1 and 2 days and within 24 h (2.8 % vs 0.6 % vs 0.7 %; p < 0.001). Patients who were operated on after 48 h exhibited an increased risk of any complication (OR 4.72, 95 % CI 1.49-16.6, p = 0.010) on multivariable models. CONCLUSION: Delays in the management of facial fractures are associated with more in-hospital complications. However, the incidence of short-term postoperative complications remains low. Injury characteristics are the primary predictor of delays in operation, however Hispanic patients independently experienced delays in care.

Facial Anthropometric Analysis of Gender-Related Characteristics in Computed Tomography.

BACKGROUND: In recent years, facial feminization surgery (FFS) has gained increasing popularity because of increases in transgender individuals and the acceptance of diversity in gender identity. However, there is still a scarcity of anthropometric research to guide evidence-based practices for FFS in Taiwan. AIM AND OBJECTIVES: The purpose of this study was to provide a reference for surgeons to achieve optimal outcomes for patients undergoing FFS. The anthropometric analysis could help surgeons meet patients' specific requirements and improve patients' alignment with their gender identity. MATERIALS AND METHODS: The study group consisted of 100 patients (50 males and 50 females) who had undergone cranial computed tomography at Chang Gung Memorial Hospital in Taiwan because of the indication of blunt injuries to the head and face with suspected skull and facial fractures. The computed tomography images were imported into the OsiriX image software to conduct an anthropometric evaluation. The parameters used in the measurements included 2 aspects: bone and soft tissue anthropometric analysis. RESULTS: Anthropometric data were obtained from 50 males (age 32.6 ± 11.4 years) and 50 females (age 33.7 ± 10.3 years). The results for bone measurements showed that both the forehead bossing length and nasal bone width in the male group were significantly greater. The frontal angle in both bone and soft tissue in the male group was significantly smaller. The chin height and bigonial width in both bone and soft tissue in the male group were significantly greater. Although the average gonial angle was greater in the female group, the difference was not significant. For the measurements of lip projection, the results showed that there was no significant difference. Although this group of Asian males had more acute nasolabial angles, the difference was not statistically significant. However, the average nasofrontal angle among females was significantly more obtuse than among males. CONCLUSION: The results revealed that Asian males tend to have more prominent superior orbital rims, wider nasal bones, and wider and taller mandibles compared with Asian females. Despite showing some trends, the gonial angle and lip projections did not reveal any significant differences, which is likely because of a large amount of variation.

Focuses, Developments, and Publication Trends in Facial Bone Aging and Related Fields: A Systematic Bibliometric Analysis (1990-2023).

There is a current lack of bibliometric analysis in facial bone aging and relevant fields. By providing clear and intuitive references, predictions, and guidance for future research, this study aims to fill the gap in the current field, summarize the related research, and guide the researchers' future work. Literature data were retrieved from the Web of Science Core Collection database. Results Analysis and Citation Report of Web of Science, and CiteSpace software were used to optimize the visualization results, including publication characteristics, disciplines, journals, literature, countries/regions, institutions, authors, research focuses, etc. A total of 277 publications were included after manual screening, and the overall trend of annual publications and citations was increasing. On the basis of the analysis, the characteristics of facial bone aging, aging of facial soft tissue, and facial rejuvenation have been the focuses of research in this field. As stem cell research advances and researchers, deepen their comprehension of facial bone aging, basic scientific research on facial bones has witnessed a growing trend.

Development of AI-Based Diagnostic Algorithm for Nasal Bone Fracture Using Deep Learning.

Facial bone fractures are relatively common, with the nasal bone the most frequently fractured facial bone. Computed tomography is the gold standard for diagnosing such fractures. Most nasal bone fractures can be treated using a closed reduction. However, delayed diagnosis may cause nasal deformity or other complications that are difficult and expensive to treat. In this study, the authors developed an algorithm for diagnosing nasal fractures by learning computed tomography images of facial bones with artificial intelligence through deep learning. A significant concordance with human doctors' reading results of 100% sensitivity and 77% specificity was achieved. Herein, the authors report the results of a pilot study on the first stage of developing an algorithm for analyzing fractures in the facial bone.

Reasons for Removal of Rigid Internal Fixation Devices in Craniofacial Surgery: A 20-year Update.

The hardware utilized for rigid internal fixation of the craniofacial skeleton has evolved over time. Thus, the reasons for the unplanned removal of hardware continue to change. The purpose of this study is to compare past (1989-1995) and present (2000-2020) patient cohorts to establish trends related to unplanned removal of craniofacial hardware. A retrospective review study was designed. Data from our institution's original publication describing the unplanned removal of craniofacial hardware (1989-1995) was obtained. Data related to patients who underwent unplanned removal of hardware from 2000 to 2020 was collected from the electronic medical record. A descriptive statistical analysis was performed to compare demographics, reasons for hardware placement, and reasons for unplanned hardware removal between cohorts. This study includes 55 patients treated from 1989 to 1995 and 184 patients treated from 2000 to 2020. The average age at hardware placement decreased from 32 years (1989-1995) to 28 years (2000-2020). The most common reason for hardware placement changed from motor vehicle accident (1989-1995) to congenital deformity (2000-2020). The length of time with hardware in situ increased from 13 months (1989-1995) to 25 months (2000-2020). The most common reason for hardware removal changed from prominent hardware (1989-1995) to hardware exposure (2000-2020). In summary, patients who underwent rigid internal fixation of the craniofacial skeleton from 2000 to 2020 retained their hardware 2 times longer than patients treated from 1989 to 1995. Factors potentially contributing to increased retention include improved surgical technique, decreased profile of hardware, and increased surgeon experience. Further studies are warranted to define preoperative risk factors for unplanned hardware removal.

Bioinformatics Study on Mechanism of Postnatal Development of Craniofacial Bone.

OBJECTIVE: The postnatal development of craniofacial bone plays a crucial role in shaping the overall structure and functionality of the skull and face. Understanding the underlying mechanisms of this intricate process is essential for both clinical and research purposes. In this study, the authors conducted a bioinformatics analysis using the Gene Expression Omnibus database to investigate the molecular pathways and regulatory networks involved in the postnatal development of craniofacial bone. METHODS: In this study, the online Gene Expression Omnibus microarray expression profiling data set GSE27976 was used to identify differentially expressed genes (DEGs) in different age groups. Protein-Protein Interaction network analyses, functional enrichment, and hub genes analysis were performed. The differences in immune infiltration and microenvironment among different types of cells were also analyzed. RESULTS: In total, 523 DEGs, including 287 upregulated and 236 downregulated genes, were identified. GO and KEGG analysis showed that the DEGs were significantly enriched in multiple signaling pathways, such as skeletal system morphogenesis, osteoblast differentiation, and stem cell differentiation. Immune infiltration and microenvironment characteristics analysis showed that there were significant differences in fibroblasts, mesenchymal stem cell, osteoblast, stroma score, and microenvironment score between the two groups. Five hub genes, including IGF1, IL1B, ICAM1, MMP2 , and brain-derived neurotrophic factor, were filled out. CONCLUSION: The findings of this study showed a significant shift in gene expression towards osteogenesis during the first 12 months after birth. These findings emphasize the critical role of the postnatal period in craniofacial bone development and provide valuable insights into the molecular mechanisms underlying this process.

LeFort III Versus Monobloc Frontofacial Advancement: A Comparative Analysis of Soft Tissue Changes.

INTRODUCTION: The LeFort III and monobloc are commonly used midface advancement procedures for patients with syndromic craniosynostosis with well characterized postoperative skeletal changes. However, the differential effects of these procedures on facial soft tissues are less understood. The purpose of this study was to critically analyze and compare the effects of these 2 procedures on the overlying soft tissues of the face. METHODS: Frontal and lateral preoperative and postoperative photographs of patients undergoing monobloc or LeFort III were retrospectively analyzed using ImageJ to measure soft tissue landmarks. Measurements included height of facial thirds, nasal length and width, intercanthal distance, and palpebral fissure height and width. Facial convexity was quantified by calculating the angle between sellion (radix), subnasale, and pogonion on lateral photographs. RESULTS: Twenty-five patients with an average age of 6.7 years (range 4.8-14.5) undergoing monobloc (n=12) and LeFort III (n=13) were identified retrospectively and analyzed preoperatively and 6.4±3.6 months postoperatively. Patients undergoing LeFort III had a greater average postoperative increase in facial convexity angle acuity (28.2°) than patients undergoing monobloc (17.8°, P =0.021). Patients in both groups experience postoperative increases in nasal width ( P <0.001) and decreases in palpebral fissure height ( P <0.001). CONCLUSIONS: Both subcranial LeFort III advancements and monobloc frontofacial advancements resulted in significant changes in the soft tissues. Patients undergoing LeFort III procedures achieved greater acuity of the facial convexity angle, likely because the nasion is not advanced with the LeFort III segment.

A Method for Precise Reduction of Facial Bone Fractures Using Intraoperative Ultrasound With a Solid Gel Pad as a Coupling Medium.

This study introduces a method to overcome technical challenges in using intraoperative ultrasound for the closed reduction of nasal bone and zygomatic arch fractures. The curvature of the face makes it difficult to apply an ultrasound probe to the facial area. We used a solid gel pad as a coupling medium during surgery to improve the scanning of facial bone fractures. The results show that the fracture sites observed on preoperative computed tomography scans can be easily visualized using intraoperative ultrasound, and real-time manipulation confirms successful reduction. The solid gel pad is light, malleable, easy to use, and provides accurate images. Overall, the use of ultrasound with a solid gel pad enhances the accuracy of closed reduction in facial bone fracture surgeries, confirming fracture patterns and ensuring precise reduction.

Do Bicycle Helmets Protect Against Facial Fractures? An Observational Study From a Level 1 Trauma Centre.

This study investigates the impact of helmet use on the incidence of facial fractures in bicycle accidents. Analyzing data from hospitalized bicyclists between 2005 and 2016, the research focused on the correlation between helmet usage and various facial fractures. The study included 1256 bicyclists with known helmet use, among whom 277 individuals (22%) were identified with a total of 521 facial fractures. The findings revealed a significant reduction in the likelihood of facial fractures among helmeted cyclists compared with those without helmets (odds ratio, 0.65; confidence interval, 0.50-0.85; P=0.002). Specifically, the odds of sustaining fractures in the zygoma, orbit, nose, and maxilla were decreased by 47%, 46%, 43%, and 33%, respectively, among helmeted cyclists. However, helmet use did not significantly alter the odds of mandible fractures. Overall, the use of helmets in bicycling significantly lowered the risk of midface fractures but showed no notable effect on mandible fractures in severe cycling incidents.

Risk Factors for Acute-Level Hospital Course in Pediatric Craniofacial Fractures.

PURPOSE: The pediatric craniofacial trauma literature is limited to single institutions or short study periods. Herein, this study analyzes a national database over 10 years to delineate the epidemiology of pediatric craniofacial fractures and to identify risk factors for acute-level hospital course in the largest series to date. METHODS: Utilizing the National Trauma Data Bank, pediatric craniofacial fractures admitted between 2010 and 2019 were identified. Descriptive analyses and multivariable regression were performed to identify risk factors for acute-level hospital course. RESULTS: A total of 155,136 pediatric craniofacial fracture cases were reviewed, including cranial vault (49.0%), nasal (22.4%), midface (21.0%), mandibular (20.2%), and orbital floor fractures (13.7%). Midface and orbital floor fractures occurred commonly as multicraniofacial fractures. Cranial vault fractures were the most common among all age groups, but frequency declined with age. In contrast, facial fractures increased with age. Despite the inherent complexity of multicraniofacial trauma, isolated fractures remained a concern for acute-level hospital course.Cranial vault and midface fractures had an increased risk of intracranial injury and intensive care unit admission (P<0.001). Mandibular and midface fractures had an increased risk for cervical spine fracture and tracheostomy (P<0.001). Patient and injury-specific risk factors among the fractures with the strongest association for each outcome-cranial vault and mandible-were identified. CONCLUSIONS: The inherent limitations of prior studies-geographical biases, small cohorts, and short-term study periods-were addressed. Describing the independent contribution of each craniofacial fracture to the risk of acute-level hospital course outcomes can be employed to better optimize risk stratification, counseling, and management.

Successful Reduction of Unilateral Zygoma Fracture Following Bilateral Malar Reduction Surgery.

Malar reduction surgery can increase its susceptibility to fractures in case of trauma. Patients who had malar reduction surgery and sustained a zygoma fracture pose unique challenges for treatment and management. This is a case of a 28-year-old female patient who presented with a unilateral zygoma fracture following bilateral malar reduction and augmentation rhinoplasty 6 years ago. Physical examination revealed a clicking sound when opening the mouth at the right zygomatic buttress and a depressed preauricular area, suggesting arch fracture. Computed tomography imaging demonstrated a loosened screw at the right zygomatic buttress and a depressed arch fracture. She wanted to remove all plates and treat her right fractured zygoma with absorbable materials. Through the bilateral intraoral incisions, the authors removed the plates and screws and reduced the depression with the Langenbeck elevator through the same right intraoral incision without fixation. The reduction was well-maintained without complications based on postoperative plain x-rays 1 month after surgery. She reported that the pain was mostly gone and that she did not hear any abnormal sounds when opening her mouth after the surgery. In this case, if the zygomaticomaxillary buttress is minimally displaced, but the zygomatic arch fracture is significantly depressed, the authors believe that fracture reduction with only an intraoral incision would be enough to achieve an optimal outcome. If the plates and screws used in the previous malar reduction are not well maintained, it may be necessary to remove them.

Craniofacial Assault Against Women: A National Evaluation Defining At-risk Populations and Outcomes.

INTRODUCTION: Few studies have analyzed epidemiologic factor associated with female patients presenting to the emergency department from facial fractures because of assault. Clearly understanding these factors may assist in developing effective strategies to decrease the incidence and sequelae of these injuries. OBJECTIVES: To determine the epidemiology of facial fractures because of assault in the female population. METHODS: All female facial fracture visits were queried in the 2019 Nationwide Emergency Department (ED) Sample database. The likelihood of a facial fracture encounter resulting from assault was modeled using logistic regression adjusting for demographics, insurance status, geographic region, location of patient residence, and income. Secondary outcomes analyzed hospitalization costs and adverse events. RESULTS: Of all facial fractures 12.4% of female encounters were due to assault were due to assault. Of assaulted females, 72.8% were between the ages of 20 and 40, and Black women experienced a disproportionate share of assault encounters (odds ratio [OR]=2.55; CI, 2.29-2.84). A large portion (46.4%) of encounters occurred in patients living in the lowest quartile of median household income, and 22.8% of patients were uninsured (OR=1.34; CI, 1.09-1.66). Assaulted patients were more likely to have fractures in nasal bone (58.1% vs. 42.5%), orbit (16.8% vs. 10.9%), zygoma (4.1% vs 3.6%), and mandible (8.7% vs. 4.8%) compared with their nonassaulted counterparts. CONCLUSIONS: Facial fractures were especially common in lower income, uninsured, urban, and Black populations. Examining the patterns of injury and presentation are critical to improve prevention strategies and screening tools, identifying critical patients, and develop a more efficient and effective system to treat and support female patients suffering facial fractures secondary to assault.