Clinical Significance of Diplopia and the Orthoptic Examination in Zygomatic Maxillary Complex Fractures.

Literature describes variable rates of diplopia of associated with zygomatic maxillary complex (ZMC) fractures (6% to 40%). The aim of this study was to retrospectively assess the prevalence of diplopia in ZMC fracture patients, the usefulness of the orthoptic evaluation compared with the clinical finger-tracking examination, and to seek possible relations of this symptom with clinical parameters. Data of patients attending the Maxillofacial Surgery Units of the University of Messina and University of Naples "Federico II", between January 2012 and December 2022 were retrieved. Statistical analysis of positive versus negative diplopia at both the clinical examination and the orthoptic evaluation and subgroup analysis were performed. 320 patients were included in the analysis. 50 (15.6%) patients reported diplopia at the clinical examination, whereas 70 (21.9%) resulted positive at the orthoptic evaluation. Statistical analysis for every determinant and subgroup did not show statistical significance ( P >0.05). Performing routine preoperative orthoptic evaluation allowed an increase of 6.3% in positive reports. Although it seems that no basic clinical parameter can predict diplopia, results suggest that the orthoptic evaluation is superior in the assessment of this symptom. Clinical analysis was shown to be a moderate/low efficient test and should not be used as a decisional standard.

Transmalar Kirshner Wire Fixation Under Ultrasound Scanning is Useful for Unstable Zygomatic Arch Fracture Combined With Zygomatic Body Fracture.

Plate fixation to zygomatic arch fractures carries the risk of facial nerve palsy and scarring of the cheek; however, without plate fixation, bone deviation or displacement may reoccur after surgery. Furthermore, zygomatic arch fractures combined with zygomatic body fractures are more postoperatively unstable than single zygomatic arch fractures. Few reports have focused on this combined fracture type, and no consensus has been reached regarding treatment. Because plate fixation for slight deviation of the zygomatic body has little advantage for stabilization, the authors, usually opt for transmalar pinning alone instead of plate fixation at the hospital. This study is a retrospective case series of 7 patients, among 100 zygomatic fractures excluding isolated zygomatic arch fractures, treated using transmalar pinning under ultrasound scanning. The reduction was performed through the oral and temporal incision as a surgical procedure. Under ultrasound observation, a Kirshner wire was inserted into the zygomatic body from the unaffected side while maintaining the reduced position. The wire was removed at an outpatient visit 2 to 3 months following surgery. In all cases, the zygomatic body was of the laterally rotated type, and postoperative morphologic evaluation showed improvement without postoperative complications. Scores were higher in middle-aged and older than in young people. Correction of zygomatic rotation also scored higher than zygomatic arch morphology. Transmalar Kirshner wire fixation under ultrasound observation is a simple and minimally invasive method for zygomatic arch fractures, which avoids the possible complications related to plate fixation.

Evaluating Mixed Reality as a Tool for Patient Education of Facial Fractures.

Background: Patients may be educated about facial fractures using two-dimensional computed tomography (2DCT); however, three-dimensional mixed reality (3DMR) goggles may improve patient education by delivering content in an immersive environment. Objective: To compare the effectiveness of 2DCT and 3DMR formats used for patient education on facial fractures, as measured by surveys. Methods: In this prospective, randomized, crossover study, video tutorials intended for facial fracture informed consent were created in 2DCT and 3DMR formats from a single CT data set of a zygomaticomaxillary complex (ZMC) fracture. Subjects were randomly assigned into two groups. Group 1 (n = 25) viewed the 2DCT tutorial, answered self-assessment and information recall surveys, viewed the 3DMR tutorial, repeated the prior surveys as well as a comparison survey. Group 2 (n = 25) followed the same sequence but viewed the 3DMR tutorial and then the 2DCT tutorial. Results: Participants (n = 50) had no differences in age (group 1-51.9 years/standard deviation [SD] 20.9; group 2-44.7 years/SD 17.6 years; p = 0.223), gender (group 1-10 male/15 female; group 2-11 male/14 female; p = 0.999), college education level (group 1-25 yes; group 2-25 yes; p = 0.844), or prior 2DCT or 3DMR experience (group 1-9 yes/16 no; group 2-13 yes/12 no; p = 0.393). The 3DMR format was preferred over 2DCT (p < 0.05), and it was reported to enhance understanding as compared to 2DCT (p < 0.05). No differences for information recall were noted (p = 0.753). Conclusion: In this study, participants preferred 3DMR goggles over 2DCT for a simulated ZMC fracture-informed consent.

Modified patient-specific surgical-guide-assisted precise treatment of unilateral comminuted zygomaticomaxillary complex fractures: A 5-year retrospective study.

Our study aimed to evaluate modified patient-specific surgical-guide-assisted precise treatment of unilateral comminuted zygomaticomaxillary complex (ZMC) fractures. The retrospective non-randomized study was conducted in a single hospital in China. All patients diagnosed with unilateral comminuted ZMC fractures between January 1, 2018 and December 31, 2022 were retrospectively reviewed. All patients underwent preoperative spiral computed tomography (CT). CT data were processed using software to DICOM format and transferred to Proplan CMF3.0 for preoperative virtual surgical planning and postoperative evaluation. All data were extracted from standardized electronic medical records. All statistical analyses were performed using SPSS version 20.0. The chi-square test and t-test were used for statistical analyses. The 54 included patients were divided into two comparable, equal cohorts of 27 patients, and followed up for at least 6 months. Fracture reduction was assisted using the modified patient-specific surgical guides in the guide group (23 males, four females; mean age 37.74 ± 12.07 years) and without the modified patient-specific surgical guides in the control group (20 males, seven females; mean age 37.44 ± 13.58 years). In the guide group, the mean eminence deviation between the affected and unaffected sides was 1.01 ± 0.92 mm, and the mean width deviation between the affected and unaffected sides was 1.29 ± 1.32 mm. In the control group, the mean eminence deviation between the affected and unaffected sides was 1.99 ± 1.69 mm, and the mean width deviation between the affected and unaffected sides was 2.68 ± 2.01 mm. The differences in facial protrusion (p = 0.001) and width (p = 0.003) symmetry between the affected and healthy sides of the two groups were statistically significant (p < 0.05). In conclusion, applying the modified patient-specific surgical guides to unilateral comminuted zygomaticomaxillary complex fracture reduction has the advantages of greater predictability and effectiveness, and improved bilateral ZMC symmetry. It should be noted that this approach would be especially beneficial for less-experienced surgeons.

BoneTape: A novel osteosynthetic device for the stabilization of zygomatic fractures.

BACKGROUND: The study aims to assess the safety and effectiveness of BoneTape™, a new resorbable bone fixation device, using a zygomatic fracture model in rabbits. METHODS: The study followed BoneTape™ samples and control (sham) groups over 2-, 6-, and 12-week periods post-zygomaticomaxillary (ZM) osteotomy and zygomaticofrontal (ZF) disarticulation. The osteotomized segments were analyzed for bone healing, inflammatory response, and tissue healing. µCT imaging and histological analysis were used to examine the axial alignment, offset, and quality of new bone formation. RESULTS: BoneTape™ samples demonstrated enhanced maintenance of the initial intraoperative positioning, reduced axial offset, and better alignment when compared with the control group, enabling stable bone healing under physiological loading conditions. Complete union was observed at 12-weeks in both groups. The BoneTape™ group experienced minimal immune and tissue reactions, classically associated with wound healing, and showed an increased number of giant cells at 6 and 12-weeks. CONCLUSION: BoneTape™ represents a promising advancement in osteosynthesis, demonstrating efficacy in maintaining stable zygomatic reconstruction and eliciting minimal immune response in a rabbit model. This study introduces BoneTape™ as a disruptive solution specifically designed for clinical application in cranio-maxillofacial fracture fixation, with the potential to eliminate the use of over-engineered solutions while offering benefits such as ease of application and fewer biologically disruptive steps.

Is Gillies Temporal Incision Necessary to Successfully Reduce Zygomaticomaxillary Fracture Combined With Orbital Wall Fracture?

Gillies temporal approach has been widely used to reduce zygoma fractures. Traditionally, it is the preferred method to reduce the isolated zygomatic arch fracture. It can be combined with other approaches, such as subciliary and intraoral incisions for more complex zygomatic fractures, so-called tripod fractures. In this study, the author hypothesized that complex zygomaticomaxillary bone fracture reduction can successfully be achieved without Gillies temporal incision. The author retrospectively analyzed the medical records and 3D facial Computed Tomography (CT) scans of 80 patients who had orbitozygomaticomaxillary fractures that affected >3 sites among the frontozygomatic suture, zygomaticomaxillary buttress, zygomatic arch, and orbital walls from May 2021 to August 2023. A single surgeon performed all surgical operations. All fractures were reduced with 2 incisions, lower eyelid incisions (subciliary or subconjunctival) and intraoral incisions (gingivobuccal approach), within a week of the initial traumatic event. After sufficient exposure to fractured sites using 2 incisions, the author reduced the fracture with a bony hook at the inferior orbital rim, lateral wall, or Boise elevator at the intraoral incision. All cases were successfully corrected without any complications. In conclusion, the author can successfully reduce complex zygomaticomaxillary fracture combined with orbital wall fractures without temporal Gillies approach.

Role of finite element analysis for selection of single point fixation in zygomaticomaxillary complex fracture.

BACKGROUND: One-point fixation was superior to the two and three-points fixation in minimally displaced zygomaticomaxillary complex (ZMC) fracture regarding the cost, invasiveness, scaring, number of wounds, and operation time. Accordingly, this study aimed to predict which one-point fixation is the most stable in managing minimally displaced ZMC fracture. MATERIAL & METHODS: This study simulated the different one-point fixation approaches on three ZMC models after fracture reduction and application of all forces exerted on the fractured area. The findings were represented as stress impact on the ZMC fracture and plating system as well as the inter-fragments micro-motion. RESULTS: The von misses stresses of plates for the zygomaticofrontal, infra-orbital rim, and zygomaticomaxillary buttress model were (66.508, 1.285, and1.16 MPa) respectively. While the screws' von misses for the infraorbital rim, zygomaticofrontal, and zygomaticomaxillary buttress models were (13.8, 4.05, and 1.60 MPa) respectively. Whereas, the maximum principles stress at zygomaticofrontal, zygomaticomaxillary buttress, and infraorbital rim models were (37.03, 37.01, and 34.46 MPa) respectively. In addition, the inter-fragment micro-motion for zygomaticomaxillary buttress, infraorbital rim, and zygomaticofrontal models were (0.26, 0.25, and 0.15 mm) respectively. CONCLUSION: One-point fixation at zygomaticomaxillary buttress is the preferred point because it is exposed to low stresses, and the inter-fragment micro-motion is within the approved limit with the elements in the same direction of fixation which indicates the rigid fixation. In addition, it is less palpable and scarless. TRIAL REGISTRATION: clinical trial.gov (NCT05819372) at 19/04/2023.

Combining Patient-specific Implant With Malar Reduction to Repair Mid-facial Asymmetry Caused by Craniofacial Fractures in Asians.

Mid-facial asymmetry caused by bone defect or deformation resulted from craniofacial fracture was a common secondary complication needed to repair. Patient-specific implant (PSI) designed with the unaffected side as a template is a good choice to repair this kind of facial asymmetry. However, in Asians, the broad and prominent zygomatic bone in unaffected side is not an optimal template, because the oval facial shape was considered as a more attractive appearance in Asian esthetic concept. To repair the mid-facial asymmetry and to improve the facial contour, the authors combined PSI implantation with malar reduction in one-stage surgery. The authors referred the facial proportion index (the optimal ratio of mid and lower face was 1.27) as a basis for preoperative precise design to determine the ideal facial shape of unaffected side, and used mirror image overlay technique with the ideal shape of unaffected side as a template to design the PSI. With this surgical strategy, patients not only can repair facial asymmetry but also can get a more attractive appearance.

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.

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.

Role of Intraoperative Imaging in Improving Closed Reduction of Zygomatic Arch Fractures: A Systematic Review and Meta-analysis.

PURPOSE: The use of intraoperative imaging (IOI) to improve the reduction adequacy of zygomatic arch (ZMA) fractures has been reported, but few systematic reviews have examined this topic. The aim of this review was to investigate and compare the value of IOI with conventional methods without IOI (N-IOI) for the closed reduction of ZMA fractures. METHODS: Electronic retrieval of MEDLINE, Embase, Cochrane Library, Web of Science, Scopus, and citation search until December 2, 2022, was used to identify controlled clinical trials that employed IOI for improving adequacy in closed reduction of ZMA fractures. The predictor variable was the use of IOI-yes/no (IOI vs N-IOI). The covariates included imaging technique (ultrasound, C-arm, and cone beam computed tomography) and ZMA fracture type (M-shape fracture, mechanistic force in 1 direction; variable fracture, mechanistic force in 2 directions). The primary outcome variables were the reduction adequacy of ZMA fractures (the remaining cortical step and dislocation angle) compared with the ideal mirrored position. Weighted or mean differences, risk ratios, and corresponding 95% confidence intervals were calculated, where P >.05 and I2＜50% fixed effect model was adopted, and a vice versa random effect model was adopted. RESULTS: A total of 1250 studies were identified, of which 6 studies with 259 participants were included. The meta-analysis results indicated that compared with N-IOI, IOI yielded fewer cortical steps (-1.76 [-2.42, 1.10], P ＜.00001, fixed model) and dislocation angles (-5.60 [-8.08, 3.12], P＜.00001, fixed model) in patients with variable ZMA fractures, while no significant difference was detected in the M-shape ZMA fracture (-0.72, [-2.93, 1.48], P = .52; -1.48, [-3.51, 0.55], P = .15). Although there was no significant difference in postoperative correction (0.35, [0.06, 2.01] P = .24, fixed model), all secondary revision cases occurred in the N-IOI group. Descriptive analysis showed that IOI yielded better symmetry and appearance satisfaction. CONCLUSION: IOI improved the adequacy of the procedure and led to a better postoperative appearance, especially for patients with variable ZMA fractures. Furthermore, the use of IOI avoided the risk of secondary surgery. In future studies, researchers should standardize the scale and outcomes to facilitate the intuitive evaluation of reduction adequacy.

The Value of Intraoperative Computed Tomography in the Treatment of Zygomatic Complex Fractures.

BACKGROUND: Due to the complex anatomical morphology and lack of anatomic markers on the surface of zygomatic complex (ZMC), the treatment results of ZMC fractures are often suboptimal. PURPOSE: The study aimed to evaluate the effectiveness of intraoperative computed tomography (ICT) in the treatment of unilateral ZMC fractures, and further study the feasibility of ICT to replace early postoperative Computed Tomography (CT). STUDY DESIGN, SETTING, AND SAMPLE: The investigators designed a retrospective cohort study. Adult patients who underwent surgery with unilateral ZMC fractures were enrolled. PREDICTOR VARIABLE: According to whether intraoperative CT was used, the subjects were divided into the ICT group and the control group (without ICT). MAIN OUTCOME VARIABLES: Five distances and 3 angles representing bilateral ZMC symmetry were main outcome variables. The differences of outcome variables were compared between the 2 groups and the indices of ICT group were further compared with their postoperative indices. COVARIATES: Demographics (eg age), etiology (eg traffic injury), dysfunction (eg diplopia), and surgical approach (eg vestibular incision) were collected as covariates while we conducted clinical investigation, examination, and implementation. ANALYSES: The data were analyzed using independent-samples t test, paired-samples t test, Mann-Whitney U test, and χ2 test. P value < .05 was considered statistically significant. RESULTS: A total of 60 patients (18 to 59 years) were enrolled in this study. All median values of the measurements in the ICT group were smaller than those in the control group, and the differences of horizontal displacement distance (0.56 vs 1.02 mm), anteroposterior displacement distance (1.69 vs 2.34 mm, 0.90 vs 2.35 mm), horizontal angle of bilateral zygomatic arch (2.31 vs 4.19°), and horizontal angle of bilateral zygomatic process (1.77 vs 2.94°) were significantly different between the 2 groups with P value < .05. Moreover, there was no statistically significant difference in all indices between the intraoperatively and postoperatively injured sides in the ICT group. CONCLUSIONS: ICT can improve the treatment outcomes of ZMC fractures by evaluating the fracture reduction adequacy during surgery. Moreover, ICT can replace early postoperative CT.

Changing Patterns of Zygomaticomaxillary Complex Fractures: A Retrospective Study.

BACKGROUND: Limited research exists regarding the incidence and variations of zygomaticomaxillary complex (ZMC) fracture patterns and their correlation with the mechanism of injury. Hence, further research is indicated. PURPOSE: The purpose of this study was to analyze the different ZMC fracture patterns in relation to its etiology using computed tomography scans. STUDY DESIGN, SETTING, SAMPLE: This retrospective cohort study was conducted at a single institution. The medical records of maxillofacial trauma patients from 2016 to 2020 were analyzed. Patients from any gender and all age groups with complete records diagnosed with isolated ZMC fractures were included in the study. PREDICTOR VARIABLE: The primary predictor variable was the etiology of trauma. It was categorized as road traffic accidents (RTAs), falls, interpersonal violence, fall from height, sports injuries, etc. MAIN OUTCOME VARIABLES: The primary outcome variable was the ZMC fracture patterns observed and was defined as similar to or different from the classical fracture patterns. Any type of variation noted from the classical fracture lines was defined as the secondary outcome variable. COVARIATES: Covariates included demographic variables such as age, gender, the type of vehicle involved, the type of RTA, side of fracture, associated orbital fractures, and number of ZMC points fractured. ANALYSES: Descriptive and bivariate statistics were used to measure association between the predictor and outcome variables using multiple proportions χ2 test. Statistical significance was defined at P value of <.05. RESULTS: Out of the 232 scans assessed, a total of 163 cases were included in this study. A majority of the cases belonged to a range of 21 to 30 years and showed a male predilection. The most common mode of injury was found to be RTAs (88.3%). Most cases had fracture patterns different from the classical fracture patterns (65.64%). A statistically significant association was found between the types of ZMC fracture patterns and etiology of trauma (RTA P = <.0001, falls P = .0001, and interpersonal violence P = .0001). Five different variations in ZMC fracture patterns were found and had a statistically significant association with the classical fracture lines (P < .0001). CONCLUSION AND RELEVANCE: The authors conclude that the variations in fracture patterns encountered today may be attributed to the mechanism of injury. With due consideration to the limitations of this study, the authors suggest that the treatment plan may require slight modification based on the variation of the fracture pattern. Additional intervention may also be indicated.

Acesso transconjutival com cantotomia lateral para abordagem do completo orbito-zigomático-maxilar: relato de caso / Transconjutival access with side cantotomy to approach the orbito-zygomatic-maxillary complex: case report

Objetivo: relatar um caso clínico, embasando os aspectos relativos à técnica cirúrgica transconjutival com cantotomia lateral como tratamento para fratura de COZM. Relato de caso: Paciente, gênero masculino, compareceu ao Serviço de Cirurgia e Traumatologia Bucomaxilofacial do Hospital Geral do Estado (HGE), vítima de acidente motociclístico, apresentando distopia ocular, degrau ósseo em rebordo infraorbitário direito, perda de projeção malar direita, abertura bucal limitada com desvio ipsilateral e distopia oclusal com sinais sugestivos de fratura do complexo-orbito-zigomático-maxilar direito, juntamente com fratura complexa da mandíbula. A abordagem cirúrgica para acessar o COZM contou com a técnica de incisão transconjuntival com cantotomia lateral para uma melhor visualização dos cotos ósseos fraturados. Considerações finais: a escolha por esse tipo de acesso resultou em uma abordagem cirúrgica bem-sucedida, proporcionando segurança na visualização do campo cirúrgico para posterior reabilitação do paciente, estabelecendo uma devolutiva estética e funcional, cicatriz imperceptível e consequentemente um melhor prognóstico para o paciente.(AU)

Objective: to report a clinical case, basing the aspects related to the transconjunctival surgical technique with lateral canthotomy as a treatment for COZM fracture. Case report: Patient, male gender, attended the Oral and Maxillofacial Surgery and Traumatology Service of the General Hospital of the State (HGE), victim of a motorcycle accident, presenting ocular dystopia, bone step in the right infraorbital ridge, loss of right malar projection, mouth opening limited with ipsilateral deviation and occlusal dystopia with signs suggestive of a fracture of the right orbito-zygomatico-maxillary complex along with a complex fracture of the mandible. The surgical approach to access the contoured COZM with the transconjunctival incision technique with lateral canthotomy for better visualization of the fractured bone stumps. Final considerations: the choice for this type of access resulted in a successful behavioral approach, providing security in the experience of the respiratory field for subsequent rehabilitation of the patient, establishing a devolutionary and functional aesthetics, imperceptible healing and, consequently, a better prognosis for the patient.(AU)

Treatment of Sagittal Fracture of the Zygomatic Arch Root.

A sagittal fracture at the temporal root of the zygomatic arch (ZAR) often occurs as a component of zygomaticomaxillary complex (ZMC) fractures. However, this area is difficult to access, and anchorage is limited due to the unstable structure around it. Therefore, a preauricular approach using single-screw fixation is proposed, and this study reports its results and usefulness. Forty-four patients with sagittal fractures of ZAR occurring with ZMC fractures were evaluated from 2012 to 2021. Open reduction and internal fixation were performed on all patients with ZMC fractures. Closed reduction using Dingman incision and external finger pressure in group A (indirect approach; 30 patients) and single-screw fixation using a preauricular approach in group B (direct approach; 14 patients) were performed to address sagittal fractures in ZAR. For single-screw fixation, the additional mean operation time was 11.34±3.25 minutes. On postoperative 3-dimensional computed tomography and plain radiographs, group B showed more accurate reduction and less deformity and trismus ( P <0.05). Moreover, a normal diet was initiated more quickly in group B than in group A ( P <0.05). Some cases in group A showed nonunion or malunion. This study revealed that a direct approach (group B) toward sagittal fractures of ZAR is recommended due to more accurate results and fewer complications than those observed with the indirect approach (group A). Moreover, the total operation time and complications may be lesser than those with the bicoronal approach.

Changes in Facial Symmetry Following Computer-Assisted Secondary Correction of Craniofacial Fractures.

OBJECTIVE: For patients without dysfunctions, the main purpose of secondary correction for craniofacial fractures is restoring facial symmetry. Computer-assisted surgery techniques including virtual surgical planning and intraoperative navigation provide the help to restore the bony symmetry as much as possible. The authors retrospectively quantitatively analyzed patients who received computer-assisted secondary correction for craniofacial fractures on facial symmetry pre and postoperation. METHODS: This observational study reviewed the medical records of 17 patients requiring secondary correction for craniofacial fractures. Pre and postoperative computed tomography data were used to quantitatively analyze the changes in facial symmetry and enophthalmos. RESULT: All patients enrolled in this study showed mid-facial asymmetry but without dysfunctions except for enophthalmos, and 5 patients had bone defects in the frontal-temporal area. The corrective surgical techniques were different for each patient according to their specific condition. Virtual surgical planning with or without intraoperative navigation was performed for all patients. Compared with the preoperative condition, their facial symmetry was significantly improved. The maximum discrepancy value between the affected side and the mirrored unaffected side decreased from 8.10 ± 2.69 to 3.74 ± 2.02 mm postoperatively, and the mean discrepancy value decreased from 3.58 ± 1.29 to 1.57 ± 0.68 mm. In addition, the Enophthalmos Index decreased from 2.65 to 0.35 mm. CONCLUSION: This observational study objectively demonstrated that computer-assisted secondary correction for craniofacial fractures can significantly improve facial symmetry. And the authors recommend that virtual surgical planning and intraoperative navigation should be a must step in craniofacial fracture correction.

Pediatric Le Fort, Zygomatic, and Naso-Orbito-Ethmoid Fractures.

Fractures of the pediatric midface are infrequent, particularly in children in the primary dentition, due to the prominence of the upper face relative to the midface and mandible. With downward and forward growth of the face, there is an increasing frequency of midface injuries seen in children in the mixed and adult dentitions. Midface fracture patterns seen in young children are quite variable; those in children at or near skeletal maturity mimic patterns seen in adults. Non-displaced injuries can typically be managed with observation. Displaced fractures require treatment with appropriate reduction and fixation and longitudinal follow-up to evaluate growth.

Is Convolutional Neural Network Accurate for Automatic Detection of Zygomatic Fractures on Computed Tomography?

PURPOSE: Zygomatic fractures involve complex anatomical structures of the mid-face and the diagnosis can be challenging and labor-consuming. This research aimed to evaluate the performance of an automatic algorithm for the detection of zygomatic fractures based on convolutional neural network (CNN) on spiral computed tomography (CT). MATERIALS AND METHODS: We designed a cross-sectional retrospective diagnostic trial study. Clinical records and CT scans of patients with zygomatic fractures were reviewed. The sample consisted of two types of patients with different zygomatic fractures statuses (positive or negative) in Peking University School of Stomatology from 2013 to 2019. All CT samples were randomly divided into three groups at a ratio of 6:2:2 as training set, validation set, and test set, respectively. All CT scans were viewed and annotated by three experienced maxillofacial surgeons, serving as the gold standard. The algorithm consisted of two modules as follows: (1) segmentation of the zygomatic region of CT based on U-Net, a type of CNN model; (2) detection of fractures based on Deep Residual Network 34(ResNet34). The region segmentation model was used first to detect and extract the zygomatic region, then the detection model was used to detect the fracture status. The Dice coefficient was used to evaluate the performance of the segmentation algorithm. The sensitivity and specificity were used to assess the performance of the detection model. The covariates included age, gender, duration of injury, and the etiology of fractures. RESULTS: A total of 379 patients with an average age of 35.43 ± 12.74 years were included in the study. There were 203 nonfracture patients and 176 fracture patients with 220 sites of zygomatic fractures (44 patients underwent bilateral fractures). The Dice coefficient of zygomatic region detection model and gold standard verified by manual labeling were 0.9337 (coronal plane) and 0.9269 (sagittal plane), respectively. The sensitivity and specificity of the fracture detection model were 100% (p＞.05). CONCLUSION: The performance of the algorithm based on CNNs was not statistically different from the gold standard (manual diagnosis) for zygomatic fracture detection in order for the algorithm to be applied clinically.

Virtual Surgical Planning and 3-Dimensional Printing for the Treatment of Zygomaticomaxillary Complex and/or Orbital Fracture.

BACKGROUND: Traditionally, in zygomaticomaxillary complex and orbital fractures, miniplates and titanium orbital mesh are used and adapted intraoperatively, which may cause fatigue of the metal and increase the surgical time. Recently, computer-assisted surgery and 3-dimensional printing enable the surgeon to employ 3-dimensional segmentation and mirroring tools, which mimic the pretraumatized anatomy on which the miniplates and titanium orbital mesh are preoperatively molded to precisely duplicate the orbital volume, enophthalmos, and zygomatic bone position. AIM: To evaluate the results of computer technology using 3-dimensional printing model to prebend miniplates and titanium orbital mesh in the restoration of orbital volume, enophthalmos, and zygomatic bone position in the initial management of patients with zygomaticomaxillary complex and/or orbital fractures. PATIENTS AND METHODS: This prospective clinical study included 10 Iraqi male patients who met the eligibility criteria and subjected to open reduction and internal fixation utilizing virtual surgical planning and a 3-dimensional model to prebend miniplates and titanium orbital mesh as a treatment modality for facial fractures. The data were analyzed according to the orbital volume, enophthalmos, zygomatic bone position, age, gender, etiology of the fracture, and complications. The patients were radiographically followed up with a computed tomography scan at 4 months postoperatively. The statistical analysis was performed using percentages, the mean±SD, Shapiro-Wilk test, Paired t test, One Way Anova, and Independent t test. RESULTS: The age of the patients ranged from 18 to 66 years, with an average of 28.6 years and a SD of±14.5 years. Regarding gender, all patients were males. By utilizing virtual surgical planning and 3-dimentional model to prebend miniplates and titanium orbital mesh and concerning the fracture types, which include the zygomaticomaxillary complex, orbital, and combined fractures, there was no significant difference between the measurement of intact side and 4 months postoperatively in orbital volume, enophthalmos, and zygomatic bone position ( P >0.05). CONCLUSION: This study demonstrated that computer-aided techniques, virtual planning, and the use of prebend miniplates and titanium orbital mesh enable anatomically precise reduction and fixation of the orbital, zygomaticomaxillary complex, and combined fractures regarding orbital volume, enophthalmos, and zygomatic bone position.

Design and Use of a Pair of Computer-Designed Surgical Templates in Reduction of a Comminuted Zygomatic Arch Fracture.

BACKGROUND: Isolated depressed zygomatic arch fractures are often treated with closed reduction. Reduction is usually performed through the Gillies approach or Keen approach. comminuted zygomatic arch fractures generally require open reduction and fixation to achieve good results. This article describes how to use a pair of surgical templates to assist in the fixation of comminuted zygomatic arch fractures with absorbable plates. METHODS: A pair of computer-designed surgical templates were applied to restore the main part of zygomatic arch. Placing a surgical template on the medial side of the zygomatic arch can provide a supporting force and improves the stability of the reduced bone fragments. The lateral template of zygomatic arch limits the excessive uplift of bone fragments. RESULTS AND DISCUSSION: The operation was performed according to the predetermined procedure. Postoperative computed tomography showed satisfactory reduction effect. In conclusion, with the aid of surgical templates, the reduction and fixation of comminuted zygomatic arch fractures can be more easily performed using absorbable plates.