The aim of this article was to evaluate the efficacy of tranexamic acid (TXA) to reduce blood loss after maxillofacial fracture surgery. Clinical data were collected retrospectively on patients with unilateral fractures of the zygomaticomaxillary complex (ZMC) or mandibular condyle. Patients were then further divided into TXA and control groups according to whether or not TXA was used after surgery. The amount of postoperative blood loss was evaluated by negative pressure drainage volume. Data were statistically analysed. In patients with unilateral ZMC fractures, total postoperative blood loss in the TXA group was about 30 ml less than that in the control group (p = 0.006). It was significantly less on the first and second postoperative days. However, in patients with unilateral mandibular condylar fractures, there was no significant difference between the TXA and control groups (p = 0.917). TXA can reduce postoperative bleeding in patients with ZMC fractures, and the optimal usage time is on the first and second postoperative days. For patients with mandibular condylar fractures, TXA may not be used.

OBJECTIVE: The purpose of this study was to retrospectively evaluate the feasibility of 2-point fixation using absorbable plates by the transoral approach in the management of the zygomatic complex (ZMC) fractures.
METHODS: Twenty-five patients (15 male and 10 female, age range 16 y to 55 y) with Knight and North Group Ⅲ zygomatic fractures were included in this case series. Open reduction by intraoral approach was performed on these patients, and the fractures were fixed using absorbable plates placed at the zygomaticomaxillary buttress and infraorbital rim. Postoperatively, follow-up was undertaken to evaluate the fracture healing, mouth opening, facial asymmetry, diplopia, and paresthesia.
RESULTS: Postoperatively, all patients achieved uneventful healing; facial symmetry and wound healing were achieved, along with sensory recovery involving the infraorbital nerve. Complications such as sensory disturbances, infection, diplopia, malunion, and nonunion were not encountered in these patients.
CONCLUSIONS: Two-point fixation using absorbable plates by transoral approach can provide sufficient stabilization for Knight and North Group III zygomatic fractures.

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.

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.
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.
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.
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.

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.
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).
The investigators designed a retrospective cohort study. Adult patients who underwent surgery with unilateral ZMC fractures were enrolled.
According to whether intraoperative CT was used, the subjects were divided into the ICT group and the control group (without ICT).
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.
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.
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.
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.
ICT can improve the treatment outcomes of ZMC fractures by evaluating the fracture reduction adequacy during surgery. Moreover, ICT can replace early postoperative CT.

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.

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.
RESULTS: 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.
CONCLUSIONS: 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.

OBJECTIVE: This study aimed to assess the maxillary sinus volume (MSV), Chronic Sinusitis incidence, and asymmetry of the zygomaticomaxillary complex (ZMC) following ZMC fracture surgery with various numbers of fixation points.
METHODS: In a prospective non-randomized cohort, 50 adults with unilateral ZMC fractures who treated by open reduction and internal fixation (ORIF) between November 2019 and October 2021 were assigned to accomplish this study. They distributed into three groups as per fixation points (2, 3, or 4 Points). Preoperative (T1), Immediate postoperative (T2), and follow-up (T3) cone beam computed topography were analyzed using the Mimics software. The main measures were MSV and asymmetry indexes (ASI) of six paired bilateral anatomical landmarks (Orbital, Suprajugal, Jugale, Zygon, Maxillozygion 1, and Maxillozygion 2).
RESULTS: MSV decreased significantly on the affected sides postoperatively in 2P and 3P groups, both in T2 and T3. Further, the T2-T3 comparisons showed a significant MSV change (p = 0.001). ASI reduced considerably to clinically tolerated levels (<3 mm) on landmarks near the fixation sites postoperatively. The ASI on the Zygon and Maxillozygion 1 landmarks showed significant changes among the three groups in both T2 and T3. Interestingly, only five cases had reported postoperative sinusitis symptoms.
CONCLUSIONS: Although the MSV was changed among the different fixation point groups, the incidence of chronic sinusitis was uncommon. Bilateral asymmetry affected by number and position of the fixation points, fixation with 4 points provide more symmetry.

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).
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.
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).
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.

The application of a computer-aided navigation system (CANS) in zygomatic complex (ZMC) fractures has been extensively reported, but individual results are heterogeneous. The purpose of this systematic review was to evaluate the role of CANS in the surgical treatment of unilateral ZMC fractures.
Electronic retrieval of MEDLINE, Embase, and Cochrane Library (CENTRAL) and manual searching until November 1, 2022 were used to identify cohort studies and randomized controlled trials employing CANS in the surgical treatment of ZMC fractures. The identified reports contained at least 1 of the following outcome variables: accuracy of reduction, total treatment time, amount of bleeding, postoperative complications, satisfaction, and cost. Weighted or mean differences (MD), risk ratios, and corresponding 95% confidence intervals (CI) were calculated, where P＜.05 and I2＞50% random-effect model was adopted, and a vice versa fixed-effect model was adopted. Descriptive analysis was applied to qualitative statistics. The protocol was conducted in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines and prospectively registered with PROSPERO (CRD42022373135).
A total of 562 studies were identified, of which 2 cohort studies and 3 randomized controlled trials with 189 participants were included. Meta-analysis indicated that employing CANS significantly decreased the reduction error (MD = -0.86, 95% CI -1.58 to -0.14; P = .02, random-effect model) compared with conventional surgery without using CANS. The differences in total treatment time (preoperative planning time: MD = 1.44, 95% CI -3.55 to 6.43; P = .57 and operative time: MD = 3.02, 95% CI -9.21 to 15.26; P = .63, fixed-effect model) and amount of bleeding (MD = 14.86, 95% CI -8.86 to 38.58; P = .22, fixed-effect model) were not statistically significant between the two groups. Descriptive analysis suggested that postoperative complications, postoperative satisfaction, and cost were also similar with or without CANS.
Within the limitations of the present review, the reduction accuracy of unilateral ZMC fractures using CANS is superior to that of conventional surgery. CANS presents limited influence on operation time, amount of bleeding, postoperative complications, postoperative satisfaction, and cost.