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BACKGROUND: Parotidectomy can affect facial symmetry. Our study evaluated the symmetry of different facial areas and upper neck after total parotidectomy and filling the area with vascularized fat flap (VFF). METHODS: Facial symmetry was evaluated in eight patients and a control group matched in terms of gender and age, using a three-dimensional (3D) facial scanner. The operated side was compared with the non-operated side and the symmetry compared with that of the control group. Scanning was performed either within the first year (group 1; n = 5) or after 3 years (group 2; n = 3) postoperatively. RESULTS: The patients' cheek and neck areas were found to be significantly more asymmetric, but the cheek area in group 2 was significantly more symmetrical when compared with group 1. CONCLUSION: VFF appeared to achieve similar facial symmetry to the matched non-operated group. Time had a positive impact on the facial symmetry. The neck area was the most asymmetric, and proved to be unreliable, regardless of whether any procedure was performed or not.

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This article discusses the various factors that contribute to facial beauty and the different contexts in which they are significant. The authors examine the roles of the golden ratio, ideal proportions, symmetry, and specific facial features in what constitutes an attractive face. They also investigate the influence of cultural and evolutionary perspectives on facial beauty and the impact of social media on our perception of beauty. The article provides a comprehensive overview of the topic and emphasises the significance of facial beauty and its impact on our lives. The authors acknowledge that the concept of beauty is difficult to define with absolute precision, and that the objective-subjective argument regarding facial beauty remains unsolved. However, they argue that physical attributes undoubtedly influence perceptions of attractiveness, but beauty extends beyond surface-level features. They also suggest that embracing diversity in beauty standards fosters a more inclusive society that celebrates the unique qualities of every person.Level of Evidence V This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266 .

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Background and Objectives: Facial symmetry is a key component of facial beauty and attractiveness. However, perfect symmetry is rare, and slight asymmetries, also known as natural asymmetries, are common and contribute to the uniqueness of each face. The perception of facial asymmetry varies among individuals and can be influenced by several factors. This study aimed to investigate the self-perception of dento-facial asymmetry among a sample of Romanian individuals, focusing on their awareness, the extent to which it bothers them, and their desire for correction. Materials and Methods: A cross-sectional analytical study was conducted with 283 participants from Romania between January and February 2024. Participants completed a questionnaire designed to assess their self-perception of facial asymmetry and socio-demographic characteristics. The questionnaire included 10 questions on self-perception of facial asymmetry and 8 questions on socio-demographic data. Statistical analysis was performed using SPSS 26.0, and the Pearson Chi-square test was used for comparative analysis. Results: The sample was predominantly female (75.3%) with an average age of 32.24 years. Most participants were from urban areas (80.6%) and had university degrees (58.7%). About 28.7% of participants observed facial asymmetry, with dental asymmetry being the most frequently reported, followed by asymmetries in the eyebrows and eyelids. The right side of the face was more commonly perceived as asymmetric. Although 24.4% of participants were bothered by their asymmetry, 39.2% expressed a desire to correct it. Conclusions: One-third of participants identified dento-facial asymmetry, with the dental level being the most reported. A significant portion of participants expressed a desire to correct their asymmetries, highlighting the importance of understanding self-perception in the context of facial aesthetics. This study underscores the subjective nature of facial asymmetry perception and the varying thresholds for what is considered bothersome or in need of correction.

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OBJECTIVES: The primary objective of this study was to describe the distribution of the Sunnybrook Facial Grading System scores in the general population. Secondary objectives included analyzing the effects of age, gender and facial side on these scores. DESIGN: Two speech therapists specializing in facial motor skill assessment evaluated the healthy participants using the Sunnybrook Facial Grading System, first with the right hemiface as a reference and then with the left hemiface as a reference. SETTING: The study was conducted in our ENT department from September 2022 to June 2023. PARTICIPANTS: One hundred eleven healthy participants were included (57 women and 54 men), aged 18 to 79 years. MAIN OUTCOME MEASURES: SFGS composite scores (SFGS-Total) and sub-scores at rest (SFGS-Rest) and in movement (SFGS-Movement) were studied according to three age categories (18-39 years) (40-59 years) and (60-79 years) and gender. Inter-rater reliability was collected between the two evaluators with Cronbach's alpha. RESULTS: Taking the right hemiface as a reference, SFGS-Total scores ranged from 65% to 100% (median = 96, IQR [91-100]). When the left hemiface was considered as the reference, scores ranged from 78% to 100% (median = 95; IQR [90-100]). Right and left SFGS-Total scores showed high inter-rater reliability (respectively α = 0.953 and α = 0.926). There was a slight negative correlation between age and SFGS-Total scores. CONCLUSIONS: By embracing a more realistic approach that acknowledges natural variations and asymmetry in facial movements, we can enhance patient care and promote a more holistic understanding of facial rehabilitation outcomes.

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This article explores the technique of brow lift by direct excision to treat brow ptosis and rejuvenate facial appearance. Current brow lift techniques include thread lifts and traditional surgical methods such as frontotemporal lift and endoscopic lift. Direct excision stands out for its precision and ability to offer long-lasting and aesthetically pleasing results. By adjusting the amount of excised tissue and the suturing technique, surgeons can achieve a significant and harmonious brow lift. However, this method is not ideal for all patients, particularly those with thin or blond eyebrows. The article also highlights the importance of careful evaluation before combining upper blepharoplasty with a brow lift. In conclusion, direct excision is presented as the most effective and durable method for brow lifting, requiring individualized evaluation to ensure optimal aesthetic results.

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The purpose of the study was to assess the effects of a novel technique involving facial stretching of the unaffected side along with a structured exercise for the affected side on facial symmetry and facial functions as compared to conventional exercise. A hospital-based parallel-group randomized trial was completed among patients with acute Bell's palsy in Mangalore, India. Participants were randomized to receive facial stretching and a structured exercise program (experimental group) or the conventional exercise regimen (conventional group). Primary outcomes were facial symmetry and voluntary movement; assessed by the Sunnybrook Facial Grading System (SFGS). Both regimens were given for 3 weeks, with baseline, 10th day, and 20th day assessments. Out of 31 participants screened, 24 were eligible and 12 participants each were assigned to experimental and conventional groups. Change scores revealed greater improvement in the SFGS score (p = 0.002) for the experimental group participants. Facial stretching and structured exercise program exhibited promising results in enhancing facial symmetry and function in acute Bell's palsy when compared to conventional exercise regimen.

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OBJECTIVE: This study sought to three-dimensionally (3D) evaluate the maxillomandibular basal bone and dentoalveolar widths using cone-beam computed tomography (CBCT) scans in adult Chinese populations with different vertical and sagittal facial skeletal patterns whilst no apparent posterior dental crossbite. MATERIALS AND METHODS: The retrospective cross-sectional comparative study enrolled CBCT images of 259 adult patients (125 males and 134 females). The subjects were divided into the hyperdivergent(n = 82), hypodivergent(n = 88), and normodivergent(n = 89) groups based on the Jarabak ratio (S-GO/N-Me), which were further divided into three subgroups of skeletal Class I, II and III, based on both the ANB angle and AF-BF parameters. ANOVA was used to analyze the extracted data of the studied groups. The intra- and inter-observer reliability was analyzed using the intra-class correlation coefficient (ICC). RESULTS: In all three vertical facial skeletal patterns, the skeletal Class II had significantly smaller mandibular basal bone width compared to skeletal Class I and Class III, both at the first molar and first premolar levels. The skeletal Class III seemed to have smaller maxillary basal bone width compared to skeletal Class I and Class II malocclusions; however, a significant difference was found only in the normodivergent pattern. As for the dentoalveolar compensation, it was most notable that in the hypodivergent growth pattern, the skeletal Class II had significantly smaller maxillary dentoalveolar width compared to the Class I and Class III groups, both at the first molar and first premolar levels. CONCLUSIONS: Based on the sample in the present study, skeletal Class II has the narrowest mandibular basal bone regardless of the vertical facial skeletal pattern. CLINICAL RELEVANCE: For Chinese adults with no apparent transverse discrepancy, the maxillomandibular basal bone and dentoalveolar widths are revealed in specific categories based on different vertical and sagittal facial skeletal patterns. In diagnosis and treatment planning, particular attention should be paid to skeletal Class II for possibly existing mandibular narrowing.

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PURPOSE: To evaluate the effectiveness and safety of electroacupuncture (EA) using intermittent wave stimulation in enhancing facial symmetry and nerve function in chronic Bell's palsy patients. METHODS: A 6-week assessor-blinded, randomized trial followed by an 18-week observational period was conducted. Sixty individuals with chronic Bell's palsy, showing no signs of recovery after 12 months, were equally divided to receive either 18 sessions of EA using intermittent wave stimulation or Transcutaneous Electrical Stimulation (TES), administered thrice weekly over 6 weeks. The primary outcome measure was the change in the total facial nerve index (TFNI) score from baseline to Week 6, with secondary outcomes including TFNI scores at Weeks 12 and 24, as well as the change in Sunnybrook Facial Grading System (SFG) score from baseline to Week 6, and SFG scores at Weeks 12 and 24. RESULTS: The EA group showed a significant improvement, with a mean total facial nerve index score increase of 24.35 (4.77) by Week 6 compared with 14.21 (5.12) in the Transcutaneous Electrical Stimulation group (P<.001). This superiority persisted during the 24-week follow-up. While no significant difference was observed in the Sunnybrook Facial Grading System score change from baseline to Week 6, variations were noted at Weeks 12 and 24. No major adverse effects were reported. CONCLUSION: EA with intermittent wave stimulation notably enhanced facial symmetry in chronic Bell's palsy patients over Transcutaneous Electrical Stimulation by Week 6, maintaining this edge throughout the follow-up.

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Objective@#To establish a three⁃dimensional cephalometric standardized value database for Anhui province , to study the craniofacial characteristics of normal adult population in Anhui , China and to provide effective information for making orthodontic and orthognathic surgery treatment plans of the craniofacial deformity.@*Methods@#160 normal occlusal volunteers were selected according to the inclusive and exclusive criteria and were photographed by Cone Beam CT (CBCT) . The coordinate system was established for the 3D model reconstructed with Dolphin based on CBCT data , and 38 hard tissue landmarks were located. 40 lines and 20 angles were defined and measured , and measurements were analyzed with SPSS 17. 0 , to evaluate craniofacial features of the overall , midface , maxilla , mandible , alveolar bone , and dentition of the standard population.@*Results@#The 3D cephalometric measurements of craniofacial hard tissues of normal adults in Anhui were obtained. The symmetry of craniofacial hard tissues was good both in males and females with the maximum asymmetry ratio of 2. 2% and the minimum of 0. 01% . The gender comparisons showed that most of lines measured of males were larger than those of females (P< 0. 01) , while there was no significant difference in the measurements of the midline deviation of upper and lower mandible , the relative deviation of the maxillary and mandible and the protrusion of upper and lower incisor. Additionally , there was no statistical significance in angles measured between genders , except for the occlusal plane angle. The results also showed that Chinese had unique facial features based on the measured data , compared with other ethnic populations.@*Conclusion@#The normal occlusal and maxillofacial hard tissue of Anhui Han has good symmetry. The gender obviously influences line measurements , with generally the measurements of males larger than females , but it has no effect on most angle measurements.

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The aim of this retrospective study was to compare mid-facial symmetry and clinical outcomes between patients treated with patient-specific and standard implants in primary fracture reconstructions of combined orbital and zygomaticomaxillary complex fractures. Patients who underwent primary reconstruction of orbital and zygomaticomaxillary complex fractures during the study period were identified and background and clinical variables and computed tomography images were collected from patient records. Zygomaticomaxillary complex dislocation and orbital volume were measured from pre- and postoperative images and compared between groups. Out of 165 primary orbital reconstructions, eight patients treated with patient-specific and 12 patients treated with standard implants were identified with mean follow-up time of was 110 days and 121 days, respectively. Postoperative orbital volume difference was similar between groups (0.2 ml for patient-specific vs 0.3 ml for standard implants, p = 0.942) despite larger preoperative difference in patient-specific implant group (2.1 ml vs 1,5 ml, p = 0.428), although no statistical differences were obtained in symmetricity or accuracy between the reconstruction groups. Within the limitations of the study it seems that patient-specific implants are a viable option for primary reconstructions of combined zygomaticomaxillary complex and orbital fractures, because with patient-specific implants at least as symmetrical results as with standard implants can be obtained in a single surgery.

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BACKGROUND: The fibula free flap is the standard of care in the reconstruction of large mandibular defects in pediatric patients, enabling adequate restoration of the facial contour. However, the unpredictable growth potential of the reconstructed mandible could influence the preservation of the initially restored symmetry over time. Being mindful of the importance of facial appearance during developmental stages, this study aimed to evaluate the long-term facial symmetry after mandible reconstruction using this technique in growing patients. PATIENTS AND METHODS: A photogrammetric analysis of facial symmetry using the "Asymmetry Index" (AI) was performed from preoperative and postoperative frontal photographs in 17 pediatric patients (9 males and 8 females) who underwent mandibular reconstruction with the vascularized fibula free flap and had a minimum follow-up of 5 years. Comparisons between preoperative and postoperative measurements-as well as postoperative comparisons between condyle-reconstructed and condyle-preserved patients-were conducted. RESULTS: The mean follow-up was 76.9 (± 19.0) months (range, 60-120). The average age at intervention was 9.23 (± 3.8) years. Mean AI was 15.31 (± 1.81) preoperatively and 3.59 (± 0.97) postoperatively. Differences between preoperative and postoperative measurements were statistically significant in all the assessed parameters (p<0.001). Postoperative differences between the condyle-reconstructed and the condyle-preserved groups were not significant (p>0.05). No secondary procedures were required to enhance symmetry in the late postoperative period. CONCLUSIONS: Mandibular reconstruction using the vascularized fibula free flap provides adequate restoration of facial symmetry that could be predictably maintained throughout the developmental period in children and adolescents, regardless of the need for condylar reconstruction.

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OBJECTIVE: To quantitatively assess three-dimensional (3D) soft tissue facial asymmetry in patients with unilateral cleft lip and palate (UCLP) who have undergone primary lip repair. DESIGN: Clinical, retrospective, comparative, methodological study. PATIENTS/PARTICIPANTS: Twenty patients with UCLP were selected after a review of the records. INCLUSION CRITERIA: Complete UCLP; surgically treated without secondary repair. An age-matched and sex-matched Control group was employed. MAIN OUTCOME MEASURES: A 3D facial symmetry plane (FSP) was obtained by superimposing the point clouds of the original 3D facial image excluding the surgical site and including lip and nose areas and those of a mirrored facial image using the iterative closest point (ICP) adjustment method. The discrepancies in the depth and angle of the normal vector of the facial surface of each point cloud between right and left sides (cleft and non-cleft sides in the UCLP group, respectively) based on FSP were calculated. RESULTS: Facial asymmetry in the UCLP group was significantly greater than in the Control group regarding both the discrepancies in the depth (1.34 ± 0.62, 0.73 ± 0.32 pixels, respectively) (P = .0004) and surface angle (18.0 ± 5.88, 12.8 ± 4.0°, respectively) (P = .0024). Biaxial assessment of the discrepancies in the depth and surface angle allowed us to visually extract UCLP patients with greater facial asymmetry. CONCLUSIONS: Facial asymmetry analysis based on 3D FSP effectively facilitates the facial asymmetry quantification and soft tissue surgical outcome evaluation in patients with UCLP.

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BACKGROUND: Synkinesis of the facial musculature is a detrimental sequalae in post-paralytic facial palsy (PPFP) patients. Detailed knowledge on the technical requirements and device properties in a high-resolution ultrasound (HRUS) examination is mandatory for a reliable facial muscle assessment in PPFP patients. We therefore aimed to outline the key steps in a HRUS examination and extract an optimized workflow schema. METHODS: From December 2020 to April 2021, 20 patients with unilateral synkinesis underwent HRUS. All HRUS examinations were performed by the first author using US devices with linear multifrequency transducers of 4-18 MHz, including a LOGIQ E9 and a LOGIQ S7 XDclear (GE Healthcare; Milwaukee, WI, USA), as well as Philips Affinity 50G (Philips Health Systems; Eindhoven, the Netherlands). RESULTS: Higher-frequency and multifrequency linear probes ≥15 MHz provided superior imaging qualities. The selection of the preset program Small Parts, Breast or Thyroid was linked with a more detailed contrast of the imaging morphology of facial tissue layers. Frequency (Frq) = 15 MHz, Gain (Gn) = 25-35 db, Depth (D) = 1-1.5 cm, and Focus (F) = 0.5 cm enhanced the image quality and assessability. CONCLUSIONS: An optimized HRUS examination protocol for quantitative and qualitative facial muscle assessments was proposed.

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INTRODUCTION: The treatment of midfacial fractures is always difficult. The purpose of this study was to verify whether optimized three-dimensional (3D) digital surgical guide plates combined with preformed titanium plates improved the treatment effect in complex midfacial fractures. PATIENTS AND METHODS: Twenty-six patients with complex midfacial fractures were recruited and randomized into three groups: ten for Group A, eight for Group B, and eight for Group C. Group A was treated with a combination of preformed titanium plates and optimized 3D digital surgical guide plates. Group B was treated with preformed titanium plates only. Group C was treated conventionally. Clinical effects, patient-reported outcome measures (PROMs), midfacial contour, facial symmetry, surgical accuracy, △orbital volume (the absolute value of the bilateral orbital volume difference), and maximum deviation were evaluated in each of the three groups. RESULTS: Group A had the best postoperative clinical effects and patient-reported outcomes. Significant improvements in midfacial contour (L1[0.72±0.29 mm, P = 0.001], L2[1.04±0.46 mm, P < 0.001]), facial symmetry (S1[0.71±0.30 mm, P < 0.001], S2[0.96±0.58 mm, P < 0.001], S3[0.86±0.40 mm, P < 0.001], S5[0.81±0.16 mm, P = 0.003], S8[0.95±0.30 mm, P < 0.001], S9[1.03±0.38 mm, P < 0.001], S11[0.64±0.46 mm, P < 0.001]) and surgical accuracy (M1[R, 0.82±0.31 mm, P < 0.001], M2[R, 0.87±0.44 mm, P < 0.001], M3[L, 0.88±0.22 mm, P = 0.004], M3[R, 1.06±0.31 mm, P = 0.003], M4[L, 0.96±0.45 mm, P = 0.008], M4[R, 1.11±0.57 mm, P = 0.003], M5[R, 0.76±0.26 mm, P < 0.001], M6[L, 1.00±0.46 mm, P = 0.003], M6[R, 1.00±0.58 mm, P = 0.001], M7[0.87±0.53 mm, P = 0.001], M8[R, 0.91±0.53 mm, P < 0.001], M9[R, 0.81±0.32 mm, P = 0.010], M10[R, 1.19±0.42 mm, P = 0.009], M11[L, 0.85±0.51 mm, P = 0.021], M11[R, 0.96±0.49 mm, P = 0.003]) were found in Group A compared with the other two groups. The results of △orbital volume and maximum deviation analysis showed an ideal surgical treatment effect in Group A. CONCLUSION: Optimized 3D digital guide plates can accurately locate preformed titanium plates and effectively improve the treatment effect in complex midfacial fractures.

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OBJECTIVE: Concave deformities and gustatory sweating are the most common complications that cause substantial patient dissatisfaction after parotidectomy. Various surgical methods to prevent these complications have been described. However, effective techniques have not been established, especially in patients with medium- to large-sized parotidectomy defects. We evaluated the utility of infrahyoid myofascial flap reconstruction of parotidectomy defects for the prevention of these complications. METHODS: We conducted a retrospective case series study in patients with a benign or malignant parotid tumor measuring over 4 cm who underwent immediate pedicle infrahyoid myofascial flap reconstruction after total or subtotal parotidectomy or total resection of either the superficial or deep parotid gland at our hospital. Subjective analyses of facial symmetry, postoperative concave deformities of the anterior neck, gustatory sweating, voice disorders, odynophagia, neck scarring in the parotid and anterior neck areas, sensory disorders, pain, and neck stiffness were performed using patient interview data. Objective evaluations of facial symmetry were made by the first or second author. Both analyses were performed after a follow-up of more than six months. Additionally, patient demographic data, clinicopathological factors, parotidectomy and skin incision types, flap survival, and postoperative complications were evaluated. RESULTS: We included eight patients (male, n=5; mean age, 69.3 years [range, 37-93 years]). Procedures included total or subtotal parotidectomy (n=4), superficial lobe parotidectomy (n=2), and deep lobe parotidectomy with partial superficial lobe parotidectomy (n=2). Infrahyoid myofascial flaps reached the cranial tip of the parotid defect without tension, and their volume sufficiently filled the parotidectomy defect in all patients. There were no local signs of insufficient blood flow within the transferred flaps. Objective and subjective assessments were made after a mean duration of 1.2 years (range, 0.6-1.8). Postoperatively, no patient subjectively reported facial asymmetry. Objectively, facial symmetry was "good" in four patients and "fair" in four patients. No distinctly visible concave deformity in the parotid or anterior neck area occurred in any patient. Gustatory sweating occurred in one patient; this individual had the largest parotidectomy defect. Only one patient experienced donor site morbidity (mild anterior neck stiffness) related to infrahyoid myofascial flap elevation. CONCLUSION: Although complete prevention of gustatory sweating was unsuccessful, infrahyoid myofascial flap reconstruction of medium- to large-sized parotidectomy defects led to postoperative facial symmetry with minimal donor site morbidity.

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Both interposition nerve grafts and masseter nerve transfers have been successfully used for facial reanimation after irreversible injuries to the cranial portion of the facial nerve. However, no comparative study of these two procedures has yet been reported. In this two-site, two-arm, retrospective case review study, 32 patients were included. Of these, 17 patients (eight men and nine women, mean age 42.1 years) underwent interposition nerve graft after tumor extirpation or trauma between 2003 and 2006 in the Ear Institute, School of Medicine, Shanghai Jiao Tong University, China, and 15 patients (six men and nine women, mean age 40.6 years) underwent masseter-to-facial nerve transfer after tumor extirpation or trauma between November 2010 and February 2016 in Shanghai Ninth People's Hospital, China. More patients achieved House-Brackmann III recovery after masseter nerve repair than interposition nerve graft repair (15/15 vs. 12/17). The mean oral commissure excursion ratio was also higher in patients who underwent masseter nerve transfer than in patients subjected to an interposition nerve graft. These findings suggest that masseter nerve transfer results in strong oral commissure excursion, avoiding obvious synkinesis, while an interposition nerve graft provides better resting symmetry. This study was approved by the Institutional Ethics Committee, Shanghai Ninth People's Hospital, China (approval No. SH9H-2019-T332-1) on December 12, 2019.

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Acellular nerve allografts conducted via chemical extraction have achieved satisfactory results in bridging whole facial nerve defects clinically, both in terms of branching a single trunk and in connecting multiple branches of an extratemporal segment. However, in the clinical treatment of facial nerve defects, allogeneic donors are limited. In this experiment, we exposed the left trunk and multiple branches of the extratemporal segment in six rhesus monkeys and dissected a gap of 25 mm to construct a monkey model of a whole left nerve defect. Six monkeys were randomly assigned to an autograft group or a xenogeneic acellular nerve graft group. In the autograft group, the 25-mm whole facial nerve defect was immediately bridged using an autogenous ipsilateral great auricular nerve, and in the xenogeneic acellular nerve graft group, this was done using a xenogeneic acellular nerve graft with trunk-branches. Examinations of facial symmetry, nerve-muscle electrophysiology, retrograde transport of labeled neuronal tracers, and morphology of the regenerated nerve and target muscle at 8 months postoperatively showed that the faces of the monkey appeared to be symmetrical in the static state and slightly asymmetrical during facial movement, and that they could actively close their eyelids completely. The degree of recovery from facial paralysis reached House-Brackmann grade II in both groups. Compound muscle action potentials were recorded and orbicularis oris muscles responded to electro-stimuli on the surgical side in each monkey. FluoroGold-labeled neurons could be detected in the facial nuclei on the injured side. Immunohistochemical staining showed abundant neurofilament-200-positive axons and soluble protein-100-positive Schwann cells in the regenerated nerves. A large number of mid-graft myelinated axons were observed via methylene blue staining and a transmission electron microscope. Taken together, our data indicate that xenogeneic acellular nerve grafts from minipigs are safe and effective for repairing whole facial nerve defects in rhesus monkeys, with an effect similar to that of autologous nerve transplantation. Thus, a xenogeneic acellular nerve graft may be a suitable choice for bridging a whole facial nerve defect if no other method is available. The study was approved by the Laboratory Animal Management Committee and the Ethics Review Committee of the Affiliated Wuxi No. 2 People's Hospital of Nanjing Medical University, China (approval No. 2018-D-1) on March 15, 2018.

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OBJECTIVES: Two-jaw orthognathic surgery (OGS) is done using either the one-splint technique with free-hand positioning of the maxillomandibular complex or the two-splint technique with intermediate splints to position the maxilla. It is uncertain which technique achieves better outcomes. This study compares frontal soft tissue symmetry and subjective patient QoL between one-splint and two-splint techniques in skeletal Class III asymmetry patients undergoing OGS with three-dimensional surgical planning. MATERIALS AND METHODS: This retrospective case-control study comprised 34 one-splint and 46 two-splint OGS patients. Frontal photographs and Orthognathic Quality of Life Questionnaire (OQLQ) were done pre- and post-treatment. Frontal soft tissue symmetry was analysed with the anthropometric Facial Symmetry Index. Measurements were compared with t-tests and chi-squared tests with p-value set at 0.05. RESULTS: The groups differed in pre-treatment ANB and OQLQ scores. The two-splint group showed significant improvement in all symmetry measures. The one-splint group showed significant improvement in all symmetry measures except midface deviation, upper contour deviation and the Facial Contour Symmetry Index. Both groups showed significant improvement in OQLQ scores. There were no significant differences in post-treatment symmetry measurements and OQLQ scores between groups. CONCLUSIONS: Although two-splint technique may better improve contour symmetry, there were no significant differences in frontal soft tissue symmetry and QoL after OGS in skeletal Class III asymmetry with either one-splint or two-splint technique, with both techniques resulting in significant improvement. CLINICAL RELEVANCE: One-splint and two-splint surgical techniques produce similar patient-centred outcomes in Class III asymmetry patients.

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The objective of this study was to evaluate the use of 3D modified digital surgical guide plates combined with preformed titanium plates in the treatment of complex mandibular fractures. Patients with complex mandibular fractures were randomized into three groups. Group A was treated with a combination of 3D modified digital surgical guide plates and preformed titanium plates, Group B was treated with preformed titanium plates only, and Group C was treated conventionally. The key design point of the guide plates is the "slot" structure, which is crucial for accurately locating the preformed titanium plate. Clinical outcomes, including facial symmetry, surgical accuracy, and maximum deviation were quantitatively assessed postoperatively. Twenty-two patients were recruited for this study, eight for Group A, six for Group B, and eight for Group C. Group A exhibited better postoperative clinical outcomes. Among three groups, significant improvements were found in Group A for facial symmetry (S1 [0.74 ± 0.17 mm, P < 0.001], S2 [0.86 ± 0.21 mm, P = 0.004], S3 [0.92 ± 0.26 mm, P < 0.001], S4 [0.32 ± 0.09 mm, P < 0.001], S5 [0.47 ± 0.16 mm, P = 0.042], S6 [0.35 ± 0.04 mm, P = 0.001], S10 [0.50 ± 0.31 mm, P = 0.048], S11 [0.97 ± 0.29 mm, P = 0.018]) and surgical accuracy (T1 [R, 0.56 ± 0.18 mm, P = 0.021], T1 [L, 0.60 ± 0.30 mm, P = 0.022], T2 [L, 0.76 ± 0.21 mm, P = 0.006], T4 [R, 0.37 ± 0.15 mm, P < 0.001], T4 [L, 0.40 ± 0.15 mm, P = 0.001], T8 [R, 0.40 ± 0.15 mm, P = 0.007], T8 [L, 0.31 ± 0.29 mm, P = 0.001], T9 [L, 0.51 ± 0.33 mm, P = 0.042], T10 [R, 0.58 ± 0.28 mm, P = 0.049], T10 [L, 0.53 ± 0.34 mm, P = 0.046], T11 [R, 0.54 ± 0.13 mm, P = 0.021], T12 [0.45 ± 0.16 mm, P = 0.003]). The ideal postoperative effect was found in Group A with maximum deviation analysis. 3D printed modified digital surgical guide plates can effectively improve treatment outcomes in complex mandibular fractures.

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Orthognathic surgery (OGS) is frequently used to correct facial deformities associated with skeletal malocclusion and facial asymmetry. An accurate evaluation of facial symmetry is a critical for precise surgical planning and the execution of OGS. However, no facial symmetry scoring standard is available. Typically, orthodontists or physicians simply judge facial symmetry. Therefore, maintaining accuracy is difficult. We propose a convolutional neural network with a transfer learning approach for facial symmetry assessment based on 3-dimensional (3D) features to assist physicians in enhancing medical treatments. We trained a new model to score facial symmetry using transfer learning. Cone-beam computed tomography scans in 3D were transformed into contour maps that preserved 3D characteristics. We used various data preprocessing and amplification methods to determine the optimal results. The original data were enlarged by 100 times. We compared the quality of the four models in our experiment, and the neural network architecture was used in the analysis to import the pretraining model. We also increased the number of layers, and the classification layer was fully connected. We input random deformation data during training and dropout to prevent the model from overfitting. In our experimental results, the Xception model and the constant data amplification approach achieved an accuracy rate of 90%.

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