Modeling stability post zygomatic fracture reconstruction.

Zygomaticomaxillary complex (ZMC) fracture repair is one of the most common surgical procedures performed in craniomaxillofacial trauma management. Miniplates and screws are used to stabilize the fractured bone using small local incisions, however, these procedures are not infrequently associated with hardware-related post-operative complications. The amount of fixation hardware utilized varies depending on the fracture pattern and surgical judgment, with three-point fixation being the conventionally accepted treatment. However, limited experimental testing and clinical studies have suggested that ZMC stabilization may be achieved with less than three-point fixation. In this study, we utilized a previously developed finite element modeling approach that allows for detailed bone and muscle representation to study the mechanical behavior of the fractured craniomaxillofacial skeleton (CMFS) under one, two, or three-point fixation of the ZMC. Results suggest that using a miniplate along the infraorbital rim in three-point fixation increases the amount of strain and load transfer to this region, rather than offloading the bone. Two-point (zygomaticomaxillary and zygomaticofrontal) fixation yielded strain patterns most similar to the intact CMFS. One-point (zygomaticofrontal) fixation resulted in higher tensile and compressive strains in the zygomaticofrontal region and the zygomatic arch, along with a higher tensile strain on the zygomatic body. These modeling results provide biomechanical evidence for the concept of over-engineering in the stabilization of facial fractures. Furthermore, they support previous suggestions that less than three-point fixation of ZMC fractures may be adequate to achieve uneventful healing.

Post-traumatic transocular retained foreign body in the infratemporal fossa: a near miss.

The infratemporal fossa is an uncommon site for lodgement of foreign bodies. Fast-moving projectiles and displaced teeth may get impacted and have been described in the literature. However, foreign body lodgement in the retromaxillary space after transorbital passage is rare. The trajectory of the foreign bodies in such cases is difficult to predict and may not be suspected in the absence of overt clinical features. The authors present a case of a wooden splinter lodged within the infratemporal fossa after the patient sustained a lid injury with an orbital floor fracture. Imaging was equivocal; hence, endoscopic surgical exploration was undertaken, revealing the foreign body. A high index of clinical suspicion and rapid intervention is needed since unsuspected foreign bodies may cause further visual, infective or neurovascular complications. Approaches should be tailored on a case-by-case basis.

The Adelaide Facial Bone Rule: A simple prediction model and clinical guideline for the presence of facial fractures using CT brain scans in victims of minor trauma.

BACKGROUND: Facial fractures bleed, resulting in high-density fluid in the sinuses (haemosinus) on computed tomography (CT) scans. A CT brain scan includes most maxillary sinuses in the scan field, which should allow detection of haemosinus as an indirect indicator of a facial fracture without the need for an additional CT facial bone scan, yet no robust evidence for this exists in the literature. The aim of this study was to determine whether the presence of haemosinus on a CT brain scan, alone or in combination with other clinical information, can predict the presence of facial fractures. METHODS: 1231 adult patients, who had both brain and facial CT scans performed on the same day, were selected from a seven year period. Patients were eligible if scans were requested for trauma. Brain and facial scans were reviewed separately for the presence of facial fractures, haemosinus, emphysema and intra-cranial haemorrhage. Prediction modelling was used to assess whether findings from brain scans could be used to identify patients requiring further CT scanning. FINDINGS: The full prediction model included four predictors and showed excellent discrimination (AUROC 0.982; 95 % CI 0.971 - 0.993). A simplified model, more suitable for clinical implementation, used only facial fractures and haemosinus as predictors. This model showed only marginally poorer discrimination (AUROC 0.964; 95 % CI 0.945 - 0.983) and excellent performance on other measures. CONCLUSION: Based on the excellent performance of the simplified prediction model, we present the Adelaide Facial Bone Rule: The absence of blood in the sinuses or facial fractures on a CT brain scan means a CT facial bone scan does not need to be routinely performed in the setting of clinically-determined minor trauma.

The accuracy and reliability of different midsagittal planes in the symmetry assessment using cone-beam computed tomography.

Symmetry is an essential component of esthetic assessment. Accurate assessment of facial symmetry is critical to the treatment plan of orthognathic surgery and orthodontic treatment. However, there is no internationally accepted midsagittal plane (MSP) for orthodontists and orthognathic surgeons. The purpose of this study was to explore a clinically friendly MSP, which is more accurate and reliable than what is commonly used in symmetry assessment. Forty patients with symmetric craniofacial structures were analyzed on cone-beam computed tomography (CBCT) scans. The CBCT data were exported to the Simplant Pro software to build four reference planes that were constructed by nasion (N), basion (Ba), sella (S), odontoid (Dent), or incisive foramen (IF). A total of 31 landmarks were located to determine which reference plane is the most optimal MSP by comparing the asymmetry index (AI). The mean value of AI showed a significant difference (p < 0.05) among four reference planes. Also, the mean value of AI for all landmarks showed that Plane 2 (consisting of N, Ba, and IF) and Plane 4 (consisting of N, IF, and Dent) were more accurate and stable. In conclusion, the MSP consisting of N, Dent, and IF shows more accuracy and reliability than the other planes. Further, it is more clinically friendly because of its significant advantage in landmarking.

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.

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.

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.

Serial assessment and long-term radiographic evaluation of the maxillary sinus after inferior maxillectomy and soft tissue free flap reconstruction in patients with oral cancer.

PURPOSE: This study evaluates serial radiographic changes in the maxillary sinus of patients with oral cancer after an inferior maxillectomy and a soft tissue free flap reconstruction. METHODS: Fifty-six patients were evaluated between Oct 2005 and Mar 2017 from an institutional database. Preoperative and surveillance imaging was reviewed at set time-points. Maxillary sinus scores were allotted based on a modification of the Lund-MacKay staging system. Patients were evaluated for change in sinus score. A univariate (UV) and multivariate (MV) analysis was performed. RESULTS: There were 53.5% T3/T4 category tumors and 68% received adjuvant treatment. Median follow-up was 24.4 months. Preoperative mean sinus score was 0.27 ± 0.44 and postoperative mean sinus score at 24 months was 1.2 ± 1.3 (p = <0.001). On UV analysis advanced T-stage at 12 months (OR 6.7, 95% CI 1.2-50.3, p = 0.01) and 24 months (OR 5.2, 95% CI 1.03-36.8, p = 0.04) was associated with significantly higher sinus score. On MV analysis, advanced T-stage continued to be associated with increased odds for higher sinus score (OR 4.9, 95% CI 1.1-26.8, p = 0.039). CONCLUSION: A mild increase in postoperative sinus score is seen in this cohort of patients. Advanced T-stage is associated with increased odds for higher sinus scores.

Risk of complications in panfacial bone fracture according to surgeons: A meta-analysis.

BACKGROUND: Panfacial bone fractures pose intricate challenges because of severe fragmentation and the loss of landmarks. Surgeons use a variety of reduction techniques, including bottom-up and top-down approaches. This single proportional meta-analysis explores sequencing differences and complications between oral and maxillofacial surgery surgeons (OMSs) and plastic and reconstructive surgeons (PRSs) in treating panfacial bone fractures. METHODS: The PubMed and Scopus databases were searched systematically, and we compiled 14 studies published between 2007 and 2023 involving 1238 patients. A systematic review of the included studies was conducted in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-analyses guidelines, and data on the reduction techniques; total complication rates; and rates of malocclusion, enophthalmos, infection, asymmetry, and esthetic complications were collected. RESULTS: The bottom-up technique was the most prevalent for both types of surgeons (57.1%, 8 out of 14). Malocclusion rates (I2 = 0% for OMSs and 41% for PRSs) were similar between the groups (p = 0.72), but PRSs tended to have a lower enophthalmos rate (I2 = 0% for OMSs and 32% for PRSs) than OMSs (p < 0.01). Infection rates remained consistent across all studies. However, high heterogeneity was observed for the total complication rate (I2 = 94% for OMSs and 85% for PRSs) and asymmetry and esthetic complications (I2 = 88% for OMSs and 92% for PRSs), making direct comparison between the two groups inconclusive. CONCLUSIONS: In this study, the differences in surgical techniques and levels of interest have a greater impact on the outcomes of the panfacial bone fracture than the surgeon's specialty. However, more in-depth studies are needed to accurately pinpoint panfacial bone fracture reduction trends and differences in postoperative complications in the two expert groups.

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.

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.

The Use of Dynamic Navigation Systems as a Component of Digital Dentistry.

The development of dynamic navigation system (DNS) has facilitated the development of modern digital medicine. In the field of dentistry, the cutting-edge technology is garnering widespread recognition. Based on the principles of 3-dimensional visualization, virtual design, and precise motion tracking, DNS is mainly composed of a computer, a tracking system, specialized tracer instruments, and navigation software. DNS employs a workflow that begins with preoperative data acquisition and imaging data reconstruction, followed by surgical instrument calibration and spatial registration, culminating in real-time guided operations. Currently, the system has been applied in a broad spectrum of dental procedures, encompassing dental implants, oral and maxillofacial surgery (such as tooth extraction, the treatment of maxillofacial fractures, tumors, and foreign bodies, orthognathic surgery, and temporomandibular joint ankylosis surgery), intraosseous anesthesia, and endodontic treatment (including root canal therapy and endodontic surgery). These applications benefit from its enhancements in direct visualization, treatment precision, efficiency, safety, and procedural adaptability. However, the adoption of DNS is not without substantial upfront costs, required comprehensive training, additional preparatory time, and increased radiation exposure. Despite challenges, the ongoing advancements in DNS are poised to broaden its utility and substantially strengthen digital dentistry.

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.

[Post-Covid osteomyelitis of the facial bones]. / Postkovidnyi osteomielit litsevykh kostei.

The pandemic of coronavirus infection existed from 2019 to 2023. The World Health Organization (WHO) has announced on May 5, 2023 that the pandemic had ended. However, it does not cease to have an adverse effect on the health of the world population. Necrotic lesions of the bones of the facial skeleton are now a characteristic sign of a severe coronavirus infection. We conducted a review of scientific publications that reflected the relationship between coronavirus and necrotic processes of the skull bones, methods of treatment, prevention and the latest developments in this direction. The purpose of this article is to review existing studies on Post-Covid osteomyelitis of facial bones, its impact, features of the clinical picture of this disease, analysis of methods and means of treatment of this group of patients. Analysis of literature data has shown that the search for an ideal dressing material continues, especially the developments of native developers stand emphasized. The advantages of modern materials over traditional ones have become unquestionable, but further research in this direction is required.

Successful rehabilitation after multiple severe complications following orthognathic surgery: a case report.

BACKGROUND: Complications of orthognathic surgery are quite rare, but they cause suffering in affected individuals. The range of complications is broad and includes both hard and soft tissue. CASE PRESENTATION: We here present a case of a fully healthy woman without signs of impaired healing capacity. The patient underwent bimaxillary orthognathic surgery and experienced multiple complications both peri- and post-operatively. During the post operative period, the patient also suffered from soft tissue complications after an orthopaedic injury. Therefore, we referred the patient to her general practitioner for further medical investigation. We also present the result after restorative surgery and endodontic and prosthodontic treatment resulting in a successful rehabilitation. CONCLUSION: This case report clearly shows the need for a good collaboration between different odontological and medical fields to achieve a good and predictable result. In situations where normal healing processes do not occur, in-depth analysis must be carried out. HIGHLIGHTS: Orthognathic surgery affects soft and hard tissue which can result in adverse healing and complications. It is of great importance to follow up performed surgery to see late complications. Be restrictive with early re-operations when there are signs of necrosis. Always use a multidisciplinary approach when handling complications after surgery.

Soft tissue prediction in orthognathic surgery: Improving accuracy by means of anatomical details.

Three-dimensional virtual simulation of orthognathic surgery is now a well-established method in maxillo-facial surgery. The commercial software packages are still burdened by a consistent imprecision on soft tissue predictions. In this study, the authors produced an anatomically detailed patient specific numerical model for simulation of soft tissue changes in orthognathic surgery. Eight patients were prospectively enrolled. Each patient underwent CBCT and planar x-rays prior to surgery and in addition received an MRI scan. Postoperative soft-tissue change was simulated using Finite Element Modeling (FEM) relying on a patient-specific 3D models generated combining data from preoperative CBCT (hard tissue) scans and MRI scans (muscles and skin). An initial simulation was performed assuming that all the muscles and the other soft tissue had the same material properties (Homogeneous Model). This model was compared with the postoperative CBCT 3D simulation for validation purpose. Design of experiments (DoE) was used to assess the effect of the presence of the muscles considered and of their variation in stiffness. The effect of single muscles was evaluated in specific areas of the midface. The quantitative distance error between the homogeneous model and actual patient surfaces for the midface area was 0.55 mm, standard deviation 2.9 mm. In our experience, including muscles in the numerical simulation of orthognathic surgery, brought an improvement in the quality of the simulation obtained.

Joint multi-ancestry and admixed GWAS reveals the complex genetics behind human cranial vault shape.

The cranial vault in humans is highly variable, clinically relevant, and heritable, yet its genetic architecture remains poorly understood. Here, we conduct a joint multi-ancestry and admixed multivariate genome-wide association study on 3D cranial vault shape extracted from magnetic resonance images of 6772 children from the ABCD study cohort yielding 30 genome-wide significant loci. Follow-up analyses indicate that these loci overlap with genomic risk loci for sagittal craniosynostosis, show elevated activity cranial neural crest cells, are enriched for processes related to skeletal development, and are shared with the face and brain. We present supporting evidence of regional localization for several of the identified genes based on expression patterns in the cranial vault bones of E15.5 mice. Overall, our study provides a comprehensive overview of the genetics underlying normal-range cranial vault shape and its relevance for understanding modern human craniofacial diversity and the etiology of congenital malformations.

Intermittent hypoxia in neonatal rodents affects facial bone growth.

Preterm human infants often show periodic breathing (PB) or apnea of prematurity (AOP), breathing patterns which are accompanied by intermittent hypoxia (IH). We examined cause-effect relationships between transient IH and reduced facial bone growth using a rat model. Neonatal pups from 14 timed pregnant Sprague-Dawley rats were randomly assigned to an IH condition, with oxygen altering between 10% and 21% every 4 min for 1 h immediately after birth, or to a litter-matched control group. The IH pups were compared with their age- and sex-matched control groups in body weight (WT), size of facial bones and nor-epinephrine (NE) levels in blood at 3, 4, and 5-weeks. Markedly increased activity of osteoclasts in sub-condylar regions of 3-week-old IH-treated animals appeared, as well as increased numbers of sympathetic nerve endings in the same region of tissue sections. Male IH-pups showed significantly higher levels of NE levels in sera at 3, 4 as well as 5-week-old time points. NE levels in 4- and-5-week-old female pups did not differ significantly. Intercondylar Width, Mandible Length and Intermolar Width measures consistently declined after IH insults in 3- and 4-week-old male as well as female animals. Three-week-old male IH-pups only showed a significantly reduced (p < 0.05) body weight compared to those of 3-week controls. However, female IH-pups were heavier than age-matched controls at all 3 time-points. Trabecular bone configuration, size of facial bones, and metabolism are disturbed after an IH challenge 1 h immediately after birth. The findings raise the possibility that IH, introduced by breathing patterns such as PB or AOP, induce significantly impaired bone development and metabolic changes in human newborns. The enhanced NE outflow from IH exposure may serve a major role in deficient bone growth, and may affect bone and other tissue influenced by that elevation.