In the field of craniomaxillofacial plastic surgery intraoperative navigation, existing systems often lack effective visual integration of multi-source information-such as real-time visualization of surgical instruments and warnings for hazardous areas-limiting their applicability primarily to pre-clinical research settings. Fully leveraging the potential of Mixed Reality (MR) and Augmented Reality (AR) is crucial to addressing these limitations. This paper proposes an innovative approach through the development of a specialized mixed reality versatile platform. By integrating a preoperative planning and navigation system with a customized occlusal guide and a novel registration method, the platform is designed to improve intraoperative navigation in the complex context of craniomaxillofacial surgery. A series of phantom and cadaver experiments were conducted to rigorously evaluate the system's feasibility and effectiveness. The experimental results demonstrate that, through modular core and expansion components, the platform can be flexibly adapted to meet the navigation needs of various surgical procedures, enabling more precise and intuitive guidance with the potential to significantly enhance surgical workflows and patient outcomes in this specialized domain.

Botulinum toxin type A (BoNT-A) is commonly used in neuromuscular disorders and cosmetic fields, but the detailed histological and subcellular changes in masticatory muscles, mainly in masseter, remain underexplored. The literature review was conducted using the PubMed and Cochrane databases between January 2000 and September 2024. Studies of BoNT-A injection in masseters with available full- text and extractable data were included and were grouped depending on injected species. The sample size, dose of injection, follow-up duration, and detailed muscle changes were concluded. Fourteen articles were eligible for reviewing, among which 2 were conducted on humans, and 12 were conducted on animals including rats (n=5), mice (n=2), rabbits (n=3) and pigs (n=2). Morphological analysis showed muscle atrophy with variable recovery. Histological findings included decreased fiber diameter, disrupted arrangements, and shifts in myosin-heavy-chain fiber types. Immunohistochemistry indicated increased cell proliferation and nuclear centralization. Electrophysiological assessments demonstrated reduced EMG amplitudes and shorter signal durations, correlating with muscle size and bite force. Ion analysis revealed increased sodium, chloride and sulfur, and decreased potassium and phosphorus. BoNT-A injection causes dose-dependent denervation and dysfunction in masticatory muscles, with incomplete recovery over time. However, due to very limited human data, these findings should be interpreted cautiously, and strong clinical extrapolations are not justified. These findings provide valuable insights into the long-term effects of BoNT-A on muscle structure and function, highlighting the need for further research into the mechanisms underlying these changes and their clinical implications for both therapeutic and aesthetic applications. 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 .

Radio-frequency assisted liposuction (RFAL) is a minimally invasive procedure that harnesses the subcutaneous fat and fascia for thermal skin tightening and subcutaneous tissue remodeling. It has gradually become an ancillary procedure to excisional facial surgeries, such as facelift, liposuction, and blepharoplasty. This study aims to report and summarize the complications of RFAL combination therapy. We reported two unusual cases of temporary orbicular oculi muscle palsy, asymmetry of blinking, and opthalmospasm after transconjunctival lower blepharoplasty combined with RFAL. In addition, we performed a systematic review of the English literature on complications of RFAL combination therapy. The bibliographic search retrieved 16 studies involving 1181 cases conducting ancillary RFAL in the face and neck and retrieved 27 studies involving 2522 cases conducting RFAL in body contouring. The overall complication rate for the RFAL procedure is 5 www.springer.com/00266 .

This meta-analysis compares the accuracy of mandible-first and maxilla-first approaches in bimaxillary orthognathic surgery to improve clinical decision-making. A systematic search was performed in PubMed, Web of Science, Embase, and Cochrane databases up to August 2024. The analysis included randomized controlled trials and cohort studies with a minimum of 10 patients. Data extraction followed Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines, and pooled effect estimates for continuous outcomes were calculated using weighted mean difference (WMD) with 95% CIs. Heterogeneity was assessed using Cochran I 2 and Q statistics, with a random-effect model applied when I 2 exceeded 50%. Seven studies involving 316 patients were included. The analysis showed no significant differences in vertical (WMD: -0.05, 95% CI: -0.57 to 0.48, P = 0.86), transverse (WMD: -0.17, 95% CI: -0.43 to 0.09, P = 0.21), and sagittal (WMD: -0.41, 95% CI: -0.98 to 0.15, P = 0.15) surgical errors between the two approaches. Rotational surgical errors were also similar, including pitch (WMD: 0.07, 95% CI: -0.11 to 0.25, P = 0.29), roll (WMD: 0.01, 95% CI: -0.18 to 0.25, P = 0.69), and yaw (WMD: 0.12, 95% CI: -0.56 to 0.81, P = 0.72). The findings suggest that there is no significant difference in surgical accuracy between mandible-first and maxilla-first approaches. Therefore, the choice of sequence should be based on patient-specific factors rather than a presumed advantage of one method over the other. Further research, including large-scale randomized controlled trials, is needed to confirm these results and evaluate long-term outcomes.

BackgroundBibliometric analyses of software applications in plastic surgery are relatively limited. This study aims to address this gap by summarizing current research trends and providing insights that may guide future developments in this field.MethodsData were retrieved from the Web of Science Core Collection. Visualized results, including publication characteristics, disciplines, journals, documents, countries/regions, institutions, authors, and research focuses, were analyzed and optimized using CiteSpace and the "Results Analysis" and "Citation Reports" functions in WoSCC.ResultsA total of 339 publications were identified through manual screening, indicating a general upward trend in annual publications and citations. Key research areas in this field include computer-aided design, modeling, virtual reality, augmented reality, artificial intelligence, social media software, telemedicine, and mobile health. However, challenges such as the high costs of advanced tools, the need for specialized training, and concerns regarding data security and patient privacy are significant barriers. Addressing these issues could be crucial for broader adoption. Despite these obstacles, the potential benefits offered by these technologies suggest their increasing relevance in plastic surgery.ConclusionPlastic surgery appears to be evolving toward a more standardized, digitalized, and intelligent future. Software has the potential to transform traditional workflows in both research and practice, contributing to improvements in efficiency and precision in the field.Level of Evidence IVThis 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.

Background:Current upper eyelid blepharoplasty techniques vary widely, and many revision patients lack information of the initial procedure, making reparability assessment and surgical planning challenging. In such complex procedures, perioperative analysis of eyelid anatomy is crucial. Although magnetic resonance imaging (MRI) is valuable for studying upper eyelid anatomy and function, significant variations exist in MRI protocols, research methods, and objectives across studies. This systematic review aimed to explore MRI applications in upper eyelid anatomy and blepharoplasty and summarize factors limiting its clinical use. Methods:A systematic review of clinical studies utilizing MRI for upper eyelid anatomy and blepharoplasty was conducted by searching PubMed and Web of Science until January 5, 2025. Publications were categorized by research objectives. The study types, populations, observational tools, MRI protocols, outcomes, and conclusions were summarized. Results:Of the 12 articles reviewed, 7 detailed normal anatomy and functions, 2 identified racial anatomical disparities, 1 assessed tumor extent, and 2 highlighted anatomical changes postblepharoplasty. Dynamic MRI had proven effective for functional eyelid analysis, whereas surface microscopy coils improved spatial resolution. Limitations included protocol inconsistencies, small samples, artifacts, and cost. Conclusions:Dynamic high-resolution MRI excels in evaluating upper eyelid anatomy through superior soft-tissue contrast and quantitative analysis. It supports personalized surgical planning and objective postoperative assessments in revision and complex cases. By visualizing structural changes, it optimizes upper blepharoplasty techniques. Standardized protocols and larger cohort studies are needed to advance clinical adoption.

Botulinum neurotoxin type A (BoNT-A) is widely used to treat masseter hypertrophy, but its long-term structural effects remain unclear. While animal studies suggest reversible and irreversible remodeling, human data on microstructural changes are limited. Ultrasound elastography (USE) offers a non-invasive method to quantitatively assess muscle elasticity and detect fibrosis risk. A prospective self-controlled trial enrolled 14 subjects (28 masseter muscles) aged 21–27 years. Masseter thickness and standardized USE measurements (shear wave velocity, V median) were performed at baseline and 1, 3, and 6 months post-injection. Statistical analysis included paired t-tests and Spearman correlation. Masseter thickness decreased significantly by 28.9–31.5 www.springer.com/00266 .

Background:This study aimed to evaluate the efficacy of high-frequency ultrasound in the preoperative diagnosis of lacrimal gland prolapse to aid surgical planning, minimize complications, and enhance patient satisfaction. Methods:Five patients underwent preoperative assessment using high-frequency ultrasound. The diagnostic accuracy of the ultrasound examination was subsequently assessed in relation to intraoperative findings concerning lacrimal gland prolapse. Additionally, physical examination was used to assess the extent of swelling in the outer upper eyelid. Results:Five female patients (10 eyes), aged 25-40 (average age 33.2) years, underwent upper eyelid blepharoplasty at the Plastic Surgery Hospital, Chinese Academy of Medical Sciences, between October 2023 and March 2024. Preoperative high-frequency ultrasound identified lacrimal gland prolapse in 8 eyes, whereas intraoperative findings confirmed prolapse in 6 eyes. The ultrasound had an 80% (8 of 10) accuracy rate, with 2 eyes misdiagnosed. Lacrimal gland prolapse was identified in 6 eyes, whereas 4 eyes showed no prolapse based on physical examination. Preoperative diagnosis relying solely on physical examination led to 2 missed and 2 incorrect prolapse diagnoses, achieving a 60% accuracy rate (6 of 10). Conclusions:The high-frequency ultrasound system has high accuracy in the preoperative diagnosis of lacrimal gland prolapse, and it has good application value in the correct diagnosis and treatment of lacrimal gland prolapse.

Mandibular angle osteotomy with outer cortex grinding is an effective cosmetic procedure for correcting square faces. However, morphological changes in the mandible may also cause temporomandibular joint (TMJ) disorders. This retrospective study aimed to investigate the morphological stabilization of the TMJ and changes in masseter muscle thickness after mandibular angle osteotomy to evaluate the safety of the procedure. Data from patients who underwent mandibular angle osteotomy with outer cortex grinding between January 2016 and January 2019 were retrospectively reviewed. Preoperative and long-term follow-up (~1 y) computed tomography data were collected from these patients, and morphological changes in the TMJ and masseter muscle were analyzed. The results from the computed tomography data showed that the condylar length and condylar height were significantly reduced 1 year after the operation (P < 0.05). In addition, the morphology of the TMJ was stable, and the distance between the mandibular condyle and the glenoid fossa did not change significantly. No significant difference was observed in masseter muscle thickness before and after the operation. After mandibular angle osteotomy with outer cortex grinding, the length and height of the mandibular condyle were functionally restored without any disorders of the TMJ. Moreover, the masseter muscle exhibited stable function. In conclusion, the procedure is safe for occlusal function and suitable for popularization.

A broad midface is usually accompanied by temporal depression. Traditional reduction malarplasty may visually improve the temporal depression by the inward reduction of zygomatic arch, but also has a high risk of soft tissue sagging. Our bracing technique has been reported to have an anti-sagging effect and may have a temporal augmentation effect as observed during our long-term clinical practice. Data of patients who received reduction malarplasty with our bracing technique from September 2015 to July 2023 were retrospectively collected. The pre-op and post-op CT images of those who met the inclusion criteria were used for three-dimensional reconstruction and measurements of the thickness and volume of the temporal soft tissue as well as the elevation distance of zygomatic arch. Fifty-eight patients with an average follow-up of 18.4 ± 9.1 months were included. Despite mild thinning of the temporalis muscle after reduction malarplasty, the overall thickness of the temporal soft tissue significantly increased due to the significant thickening of the temporal adipose-fascial layer. There was a 0.5 ml-increase in the temporal volume although without statistical difference. No significant correlation was detected between the elevation distance of zygomatic arch and the temporal thickness or volume change. The bracing technique of reduction malarplasty not only plays an anti-sagging role, but also has a temporal augmentation effect through the superior bracing by the elevation and rigid fixation of the zygomatic arch. It adds brilliance to the traditional technique and can be suggested especially when the patients are disturbed by temporal depression. 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 .

Recently, the integration of 3D face scanning into smartphones has raised vast interest in plastic surgery. With the release of smartphones featuring 3D face scanning technology, users now can capture detailed 3D models of their faces using their smartphones. However, trueness and precision of this system is less well established. PubMed, Cochrane Library, Embase, ScienceDirect, Scopus, and Web of Science databases were searched for studies evaluating 3D scanning of smartphone devices and conventional 3D imaging systems from January 1, 2017, to June 1, 2023. A qualitative systematic review was conducted by two review authors after independently selecting studies, extracting data, and assessing the risk of bias of included studies. A total of 11 studies were included, all focusing on the accuracy of smartphone 3D facial scanning. The results show that although smartphones perform poorly on deep and irregular surfaces, they are accurate enough for clinical applications and have the advantage of being economical and portable. Smartphone-based 3D facial scanning has been basically validated for clinical application, showing broad clinical application prospects in plastic surgery. 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 .

BACKGROUND:Bone regeneration in the mandibular angle region after reduction mandibuloplasty may compromise the aesthetics of the lower face and thus lead to revision surgery. Bone quality is known to play an important role in osteogenesis. However, no study has evaluated the relationship between mandibular bone quality and bone regeneration volume. METHODS:The bone density of the mandibular angle immediately after surgery (BD) was determined as the grey level in computed tomography (CT) images. Based on the immediate postoperative and long-term follow-up CT images, the volumes of the regenerated angle (VSA) and the regenerated outer cortex (VOC) were measured after model reconstruction, automatic alignment and Boolean operation. Correlation analyses were then performed between VSA and BD, VOC and BD. RESULTS:23 patients (46 mandibular angles) were included in this study. The average BD was 907.09 ± 111.89 HU. The mean VSA was 201.66 (131.73-357.24) mm3. Spearman correlation analysis revealed a positive correlation between BD and VSA (r = 0.5449, p < 0.0001). The mean VOC was 236.23 ± 151.35 mm3. Pearson correlation analysis found a negative correlation between BD and VOC (r = -0.3501, p = 0.0171). CONCLUSIONS:CT images can provide a quantitative assessment of mandibular bone quality. BD may influence the volumes of bone regeneration in different areas of the mandibular angle portion after reduction mandibuloplasty, in the regenerated angle area positively and in the regenerated outer cortex region negatively. Therefore, slight over-grinding may be a choice to prevent secondary angulation.

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

Paranasal concavity is esthetically displeasing and interferes with the overall outline of the face. Paranasal augmentation with alloplastic implants is a minimally invasive procedure with significant esthetic effects for paranasal concavity. When fixing the implants, the screws should be placed on the nasofrontal column, but are occasionally mispositioned on the anterior wall of the maxillary sinus. Here, the authors introduce a case of paranasal augmentation in which the self-tapping screw accidentally penetrated through the implant, broke through the anterior and medial walls of the maxillary sinus, and entered the nasal cavity. The screw was located by a computed tomography scan and was successfully removed under a nasal endoscope. The causes of this intraoperative complication were analyzed, emergent management was introduced, and a further preventive strategy was proposed.

There is currently a lack of scientific bibliometric analyses in the field of Pierre Robin sequence (PRS). Pierre Robin sequence is known for its clinical triad of micrognathia, glossoptosis, airway obstruction, and possible secondary cleft palate. These defects can lead to upper airway obstruction, sleep apnea, feeding difficulties, affect an individual's growth and development, education level, and in severe cases can be life-threatening. Through analysis of literature retrieved from the Web of Science Core Collection (WoSCC) database using Results Analysis and Citation Report and Citespace software, 933 original articles and reviews were included after manual screening. The overall trend for the number of annual publications and citations was increasing. On the basis of the analysis, airway evaluation and treatment, mandibular distraction osteogenesis (MDO), as well as descriptions of PRS characteristics have been the focus of research in this field. In addition, with advances in new technologies such as gene sequencing and expanding understanding of diseases among researchers, research on genetics and etiology related to PRS has become a growing trend.

Introduction: Clear aligner (CA) therapy has become popular worldwide but there is little research in the area from the perspective of bibliometrics. The present study aimed to identify the most impactful studies on CA over its 20 years of publishing since 2002. Methods: The Web of Science database was used to retrieve study records on CA for the period between 2002 and 2022. Two authors manually screened the related studies. CiteSpace was used to analyse the country and institutional co-operation, keywords and citations with the strongest 'burst'. Results: The number of CA publications has increased and a total of 613 studies were included in the current analysis. The American Journal of Orthodontics and Dentofacial Orthopedics was the leading publishing journal reporting 79 published CA articles and 1627 total citations. Italy had the most significant productivity in this field (142/613, 23.16%). The United States of America was the leading country with the highest international collaboration. Based on the results of keyword analysis, orthodontic treatment, digital orthodontics, superimposition, and apical root resorption were previous research emphases. Conclusions: The present analysis indicates that the treatment outcomes of CA therapy is the focus of current studies and provides developments for future research. The results provide an increased and comprehensive understanding of the state of the art of CA treatment.

Cheek drooping after reduction malarplasty remains a concern for patients. To evaluate the anti-drooping effectiveness of the bracing system technique with the preservation of the zygomaticus major muscle (ZMj) bony attachment and to determine the role of ZMj in anti-drooping. A retrospective analysis was conducted of patients who accepted this method in our department from February 2016 to May 2021. Patients’ subjective evaluation and two plastic surgeons’ objective assessment of photographs were performed. The pre- and postoperative three-dimensional (3D) ZMj models were reconstructed and compared. ZMj length and tortuosity were also measured from 3D models. Twenty-two patients (44 ZMjs) met the inclusion criteria. Most patients (21/22, 95.45 www.springer.com/00266 .

This study aimed to evaluate the use of tranexamic acid in craniomaxillofacial surgery by meta-analysis. A comprehensive search was performed for randomized controlled trials (RCTs) mainly in 3 electronic databases (PubMed, EMBASE, and Cochrane Library) before August 2022. We collected and managed data for weighted mean difference of intraoperative blood loss, transfusion requirement, and operation time for the study. A total of 13 randomized controlled trials were included in the analysis. Compared with the control group, the tranexamic acid group showed a reduction in intraoperative blood loss of 198.67 ml (95% CI: −258.84 to −138.50 ml, P <0.00001), with blood transfusion requirement decreased by 7.77 ml/kg (95% CI: −10.80 to −4.73, P <0.0001) and less operation time (weighted mean difference= −10.39 min; 95% CI: −16.49 to −4.30 min, P =0.0008).

Small-incisional double eyelid surgery has been increasingly performed these years and achieved good aesthetic results, but the techniques vary greatly between literatures. The authors reviewed the cases of three-small-incisional double eyelid surgery performed in the past three years and introduced their surgical technique in detail. A total of 87 patients receiving bilateral three-small-incisional double eyelid surgery were included in this retrospective study. The pretarsal folds were designed meticulously, along which three evenly distributed 2 mm-long incisions were made. A minimal amount of orbicularis oculi muscle and pretarsal soft tissue were removed to expose the pretarsal fascia for further fixation. An appropriate amount of orbital septal fat was removed through the lateral incision if required. The superficial orbicularis oculi muscle and dermis on the lower margin of the incision were fixed onto the pretarsal fascia with some underlying tarsus on the upper margin of the tarsus. The skin was closed by one stitch for each incision. The average follow-up was 9.9 ± 5.2 months (range: 6–27 months). All the patients were satisfied with the result. None of them experienced loss of the pretarsal fold, bilateral asymmetry, scar hyperplasia, or persistent swelling after surgery. Our three-small-incisional technique with minor soft tissue debulking offers a simple, safe, and reproducible approach to double eyelids. It can create a stable and natural-looking pretarsal fold with a short recovery period. 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 .