Objective:To investigate the clinical effect of indocyanine green angiography (ICGA)-assisted design and harvest of expanded flaps for scar reconstruction.Methods:This study was a retrospective observational study. From April 2019 to August 2023, 19 patients with scars (8 males, 11 females; aged 3-38 years) treated at the Plastic Surgery Hospital of Peking Union Medical College and Chinese Academy of Medical Sciences met the inclusion criteria. The scars were distributed on the head, face, trunk, and extremities. In stage Ⅰ surgery, skin soft tissue expanders were implanted in suitable areas around the scars for skin soft tissue expansion. In stage Ⅱ surgery, the scar tissue was excised, resulting in wound areas ranging from 100 to 210 cm 2, and expanded flaps were designed. ICGA was used to identify target perforators and their accompanying veins, and the flap design was adjusted to ensure the inclusion of complete arterial and venous axes. The expanded flap with an area of 120 to 240 cm2 was harvested using unilateral back-cut technique and transferred to the recipient site, and the donor site wound was sutured directly. The durations of the arterial and venous phases of ICGA during flap design were recorded. The length-to-width ratios of the back-cut flaps were calculated for different regions. After stage Ⅱ surgery, the blood perfusion and survival of the flap, the wound healing at the donor site, and the occurrence of complications were observed. During follow-up, the appearance, color, and texture of the patient's flap were observed. Results:The arterial phase of ICGA lasted 10-27 (18±5) s, and the venous phase lasted 78-116 (100±10) s. The length-to-width ratios of the back-cut flaps were 1.22±0.32, 1.63±0.12, and 1.15±0.21 for the head and neck, trunk, and limb regions, respectively. After stage Ⅱ surgery, one patient had a large area of insufficient blood perfusion in the flap. By comparing ICGA images before and after flap transfer, the sutures at the oral commissure were loosened, the blood flow of the flap was restored. The blood perfusion of the flaps in other patients was good. All flaps survived completely, with well-healed donor site wounds and no complications. During 0.5-14.0 months of follow-up, all flaps of patients demonstrated excellent appearance, with color and texture matching the surrounding skin.Conclusions:As a means of superficial blood flow visualization, ICGA can not only clearly show the microvascular distribution of the expanded flap before operation, assist in optimizing the design of the flap, but also evaluate the blood perfusion of the flap after operation, reduce the occurrence of complications, and provide a full-process navigation for the harvesting of expanded flaps, thereby improving the safety of flap transfer for scar reconstruction.

Objective:To evaluate the accuracy of a self-developed extraoral scanning system based on photogrammetry technology, and to provide evidence for advancing the development and clinical application evaluation of domestically produced scanning devices.Methods:This research group developed a photogrammetry-based implant extraoral scanning system with customized scan bodies. Two distinct edentulous implant resin models were designed and three-dimensional (3D)-printed by Center of Digital Dentistry, Peking University School and Hospital of Stomatology, containing 6 (Model 1) and 8 (Model 2) abutment analogs respectively. Reference data acquisition was performed using a high-precision denture 3D scanner with scan caps mounted on the analogs. Specialized scan bodies were then mounted on the analogs for 3D positional data acquisition using both the self-developed system (experimental group) and the clinically established system (control group). Each system conducted 10 repeated scans per model. Trueness was assessed through root mean square error (RMSE), linear deviation (LD), and angular deviation (AD) relative to reference data, while precision was determined through intra-group RMSE analysis. Systematic comparisons included inter-group performance on identical models and intra-group variability across different models.Results:For Model 1, the experimental group showed statistically significant advantages over controls in intra-group RMSE [(3.10±0.71) μm vs (4.61±1.51) μm, P<0.001], reference-data RMSE [(21.48±0.60) μm vs (32.50±0.63) μm, P<0.001], linear deviation [23.64 (32.35) μm vs 44.86 (55.73) μm, P<0.001], and angular deviation [0.29° (0.29°) vs 0.23° (0.33°), P<0.001]. In Model 2, significant improvements were observed in intra-group RMSE [(4.47±1.58) μm vs (6.21±2.07) μm, P<0.001], reference-data RMSE [(38.84±0.86) μm vs (43.69±1.34) μm, P<0.001], and linear deviation [37.95 (50.68) μm vs 49.71 (58.89) μm, P<0.001]. Both groups exhibited model-dependent variability, with RMSE of precision and trueness of both groups, linear deviation of experimental group, angular deviation of control group showing statistically significant increases (all P<0.001) corresponding to abutment analog quantity. Conclusions:The self-developed scanning system demonstrates superior accuracy in 3D positional acquisition of abutment analogs compared to the contral group system, with implant number identified as a critical determinant of extraoral scanning accuracy.

Objective:To explore the short-term clinical effects of deep cervical lymph node-venous anastomosis in the treatment of Alzheimer’s disease (AD).Methods:A prospective exploratory study was conducted on the treatment of AD patients using the cervical deep lymph node-venous anastomosis technique in Scar and Wound Treatment Department, Plastic Surgery Hospital, Chinese Academy of Medical Sciences, from September to October 2024. The patients underwent high-frequency ultrasound to locate deep cervical lymph nodes and the external jugular vein. Under general anesthesia, bilateral deep cervical lymph node-venous anastomoses were performed. Indocyanine green (ICG) lymphography was conducted via subcutaneous injection behind the ear to visualize lymph nodes in levels Ⅱ and Ⅲ. After making a skin incision along the posterior margin of the sternocleidomastoid muscle, the external jugular vein, internal jugular veins, and associated lymph nodes were exposed. Adjacent veins were selected for anastomosis of lymph node. Using microsurgical techniques, end-to-side or end-to-end anastomosis was completed for lymph nodes in levels Ⅱ and Ⅲ. Preoperative assessments included the mini-mental state examination (MMSE, a higher score indicates better cognitive function), Alzheimer’s disease assessment scale-cognitive subscale (ADAS-Cog, a higher score indicates greater impairment of cognitive function), Alzheimer’s disease cooperative study scale for activities of daily living (ADCS-ADL, a higher score indicates better ability to perform daily activity), and neuropsychiatric inventory (NPI, a higher score indicates more severe behavioral and emotional symptom). Postoperative follow-up included the same scales to observe changes in cognitive function, activities of daily living, and emotional communication.Results:Four patients (1 male, 3 females, aged 58-79 years) with AD were included. All were diagnosed based on cerebrospinal fluid biomarkers. All patients successfully underwent bilateral deep cervical lymph node-venous anastomoses. On average, 4.3 (2-7 per person) anastomoses were performed per patient. Surgical procedures lasted an average of 6.5 h (5.5-8.5 h) with minimal blood loss (less than 50 ml). Patients resumed normal activity within 6 hours postoperatively and were discharged after an average of 4.1 d (3.5-5.0 d). Postoperative complications included one case each of aspiration pneumonia, lower limb venous thrombosis, and transient delirium, all of whom resolved without long-term effects. Clinical symptoms, including memory decline, mood swings, and anxiety, showed varying degrees of improvement. Patients reported enhanced quality of life, emotional stability, and social engagement, confirming the procedure’s safety and potential cognitive benefits. At one month postoperatively, the MMSE scores of the four patients increased by an average of 0.8 points compared to preoperative levels. Additionally, the two patients who completed the ADAS-Cog assessments showed a decrease in their scores (reduced by 1.0 points and 11.3 points, respectively, compared to preoperative scores), indicating a certain degree of improvement in cognitive function during this period. The ADCS-ADL and NPI scores of four patients varied significantly, without showing any clear pattern.Conclusion:Lymphovenous anastomosis of the deep cervical lymph node-venous anastomosis may provide a new surgical intervention approach for AD, but further large-scale studies and long-term follow-up are needed to validate its safety and effectiveness.

OBJECTIVES: This study aimed to evaluate the repeatability and reliability of a self-developed domestic wireless surface electromyography (sEMG) system (Oralmetry) in assessing the activity of the temporalis and masseter muscles to provide theoretical support for its clinical application. METHODS: Twenty-two volunteers were recruited. Through multiple repeated measurements, the sEMG signals of bilateral anterior temporalis and masseter muscles during maximum voluntary clenching were collected using the self-developed sEMG device, Oralmetry, and two commercial sEMG devices (Zebris and Teethan), filtered, screened, and standardized. Seven sEMG indicators for assessing masticatory muscle function were calculated. The intraclass correlation coefficient (ICC) was used to evaluate the repeatability of the measurements from the three sEMG devices, and statistical analysis was conducted to compare the consistency of the seven sEMG indicators obtained from the devices. RESULTS: Among the 22 participants, the ICC values of the repeated measurements from the three sEMG devices ranged from 0.88 to 0.99. The measurements of three sEMG indicators (antero-posterior coeffificient, percentage overlapping coeffificient_MM, and percentage overlapping coeffificient_TA) obtained by Zebris were significantly different from those obtained by Oralmetry and Teethan (P<0.05). No significant differences in the measurements of the seven sEMG indicators were found between Oralmetry and Teethan. CONCLUSIONS Oralmetry and the two commercial sEMG devices demonstrated good repeatability in capturing sEMG indicators for evaluating masticatory muscle function. In particular, Oralmetry showed the highest ICC values. All three devices also exhibited good consistency in measuring sEMG indicators, and a high agreement was observed between the two wireless sEMG devices (Oralmetry and Teethan). These findings provide theoretical support for the clinical application of Oralmetry.
Humans ; Electromyography/methods* ; Masseter Muscle/physiology* ; Masticatory Muscles/physiology* ; Wireless Technology ; Reproducibility of Results ; Temporal Muscle/physiology* ; Male ; Adult ; Female ; Young Adult

Objective:To investigate the clinical effect of indocyanine green angiography (ICGA)-assisted design and harvest of expanded flaps for scar reconstruction.Methods:This study was a retrospective observational study. From April 2019 to August 2023, 19 patients with scars (8 males, 11 females; aged 3-38 years) treated at the Plastic Surgery Hospital of Peking Union Medical College and Chinese Academy of Medical Sciences met the inclusion criteria. The scars were distributed on the head, face, trunk, and extremities. In stage Ⅰ surgery, skin soft tissue expanders were implanted in suitable areas around the scars for skin soft tissue expansion. In stage Ⅱ surgery, the scar tissue was excised, resulting in wound areas ranging from 100 to 210 cm 2, and expanded flaps were designed. ICGA was used to identify target perforators and their accompanying veins, and the flap design was adjusted to ensure the inclusion of complete arterial and venous axes. The expanded flap with an area of 120 to 240 cm2 was harvested using unilateral back-cut technique and transferred to the recipient site, and the donor site wound was sutured directly. The durations of the arterial and venous phases of ICGA during flap design were recorded. The length-to-width ratios of the back-cut flaps were calculated for different regions. After stage Ⅱ surgery, the blood perfusion and survival of the flap, the wound healing at the donor site, and the occurrence of complications were observed. During follow-up, the appearance, color, and texture of the patient's flap were observed. Results:The arterial phase of ICGA lasted 10-27 (18±5) s, and the venous phase lasted 78-116 (100±10) s. The length-to-width ratios of the back-cut flaps were 1.22±0.32, 1.63±0.12, and 1.15±0.21 for the head and neck, trunk, and limb regions, respectively. After stage Ⅱ surgery, one patient had a large area of insufficient blood perfusion in the flap. By comparing ICGA images before and after flap transfer, the sutures at the oral commissure were loosened, the blood flow of the flap was restored. The blood perfusion of the flaps in other patients was good. All flaps survived completely, with well-healed donor site wounds and no complications. During 0.5-14.0 months of follow-up, all flaps of patients demonstrated excellent appearance, with color and texture matching the surrounding skin.Conclusions:As a means of superficial blood flow visualization, ICGA can not only clearly show the microvascular distribution of the expanded flap before operation, assist in optimizing the design of the flap, but also evaluate the blood perfusion of the flap after operation, reduce the occurrence of complications, and provide a full-process navigation for the harvesting of expanded flaps, thereby improving the safety of flap transfer for scar reconstruction.

Objective:To evaluate the accuracy of a self-developed extraoral scanning system based on photogrammetry technology, and to provide evidence for advancing the development and clinical application evaluation of domestically produced scanning devices.Methods:This research group developed a photogrammetry-based implant extraoral scanning system with customized scan bodies. Two distinct edentulous implant resin models were designed and three-dimensional (3D)-printed by Center of Digital Dentistry, Peking University School and Hospital of Stomatology, containing 6 (Model 1) and 8 (Model 2) abutment analogs respectively. Reference data acquisition was performed using a high-precision denture 3D scanner with scan caps mounted on the analogs. Specialized scan bodies were then mounted on the analogs for 3D positional data acquisition using both the self-developed system (experimental group) and the clinically established system (control group). Each system conducted 10 repeated scans per model. Trueness was assessed through root mean square error (RMSE), linear deviation (LD), and angular deviation (AD) relative to reference data, while precision was determined through intra-group RMSE analysis. Systematic comparisons included inter-group performance on identical models and intra-group variability across different models.Results:For Model 1, the experimental group showed statistically significant advantages over controls in intra-group RMSE [(3.10±0.71) μm vs (4.61±1.51) μm, P<0.001], reference-data RMSE [(21.48±0.60) μm vs (32.50±0.63) μm, P<0.001], linear deviation [23.64 (32.35) μm vs 44.86 (55.73) μm, P<0.001], and angular deviation [0.29° (0.29°) vs 0.23° (0.33°), P<0.001]. In Model 2, significant improvements were observed in intra-group RMSE [(4.47±1.58) μm vs (6.21±2.07) μm, P<0.001], reference-data RMSE [(38.84±0.86) μm vs (43.69±1.34) μm, P<0.001], and linear deviation [37.95 (50.68) μm vs 49.71 (58.89) μm, P<0.001]. Both groups exhibited model-dependent variability, with RMSE of precision and trueness of both groups, linear deviation of experimental group, angular deviation of control group showing statistically significant increases (all P<0.001) corresponding to abutment analog quantity. Conclusions:The self-developed scanning system demonstrates superior accuracy in 3D positional acquisition of abutment analogs compared to the contral group system, with implant number identified as a critical determinant of extraoral scanning accuracy.

Objective:To explore the short-term clinical effects of deep cervical lymph node-venous anastomosis in the treatment of Alzheimer’s disease (AD).Methods:A prospective exploratory study was conducted on the treatment of AD patients using the cervical deep lymph node-venous anastomosis technique in Scar and Wound Treatment Department, Plastic Surgery Hospital, Chinese Academy of Medical Sciences, from September to October 2024. The patients underwent high-frequency ultrasound to locate deep cervical lymph nodes and the external jugular vein. Under general anesthesia, bilateral deep cervical lymph node-venous anastomoses were performed. Indocyanine green (ICG) lymphography was conducted via subcutaneous injection behind the ear to visualize lymph nodes in levels Ⅱ and Ⅲ. After making a skin incision along the posterior margin of the sternocleidomastoid muscle, the external jugular vein, internal jugular veins, and associated lymph nodes were exposed. Adjacent veins were selected for anastomosis of lymph node. Using microsurgical techniques, end-to-side or end-to-end anastomosis was completed for lymph nodes in levels Ⅱ and Ⅲ. Preoperative assessments included the mini-mental state examination (MMSE, a higher score indicates better cognitive function), Alzheimer’s disease assessment scale-cognitive subscale (ADAS-Cog, a higher score indicates greater impairment of cognitive function), Alzheimer’s disease cooperative study scale for activities of daily living (ADCS-ADL, a higher score indicates better ability to perform daily activity), and neuropsychiatric inventory (NPI, a higher score indicates more severe behavioral and emotional symptom). Postoperative follow-up included the same scales to observe changes in cognitive function, activities of daily living, and emotional communication.Results:Four patients (1 male, 3 females, aged 58-79 years) with AD were included. All were diagnosed based on cerebrospinal fluid biomarkers. All patients successfully underwent bilateral deep cervical lymph node-venous anastomoses. On average, 4.3 (2-7 per person) anastomoses were performed per patient. Surgical procedures lasted an average of 6.5 h (5.5-8.5 h) with minimal blood loss (less than 50 ml). Patients resumed normal activity within 6 hours postoperatively and were discharged after an average of 4.1 d (3.5-5.0 d). Postoperative complications included one case each of aspiration pneumonia, lower limb venous thrombosis, and transient delirium, all of whom resolved without long-term effects. Clinical symptoms, including memory decline, mood swings, and anxiety, showed varying degrees of improvement. Patients reported enhanced quality of life, emotional stability, and social engagement, confirming the procedure’s safety and potential cognitive benefits. At one month postoperatively, the MMSE scores of the four patients increased by an average of 0.8 points compared to preoperative levels. Additionally, the two patients who completed the ADAS-Cog assessments showed a decrease in their scores (reduced by 1.0 points and 11.3 points, respectively, compared to preoperative scores), indicating a certain degree of improvement in cognitive function during this period. The ADCS-ADL and NPI scores of four patients varied significantly, without showing any clear pattern.Conclusion:Lymphovenous anastomosis of the deep cervical lymph node-venous anastomosis may provide a new surgical intervention approach for AD, but further large-scale studies and long-term follow-up are needed to validate its safety and effectiveness.

Objective:To develop an original-mirror alignment associated deep learning algorithm for intelligent registration of three-dimensional maxillofacial point cloud data,by utilizing a dynamic graph-based registration network model(maxillofacial dynamic graph registration network,MDGR-Net),and to provide a valuable reference for digital design and analysis in clinical dental applications.Methods:Four hundred clinical patients without significant deformities were recruited from Peking University School of Stomatology from October 2018 to October 2022.Through data augmentation,a total of 2 000 three-dimensional maxillofacial datasets were generated for training and testing the MDGR-Net algorithm.These were divided into a training set(1 400 cases),a validation set(200 cases),and an internal test set(200 cases).The MDGR-Net model constructed feature vectors for key points in both original and mirror point clouds(X,Y),established correspondences between key points in the X and Y point clouds based on these feature vectors,and calculated rotation and translation matrices using singular value decomposi-tion(SVD).Utilizing the MDGR-Net model,intelligent registration of the original and mirror point clouds were achieved,resulting in a combined point cloud.The principal component analysis(PCA)algorithm was applied to this combined point cloud to obtain the symmetry reference plane associated with the MDGR-Net methodology.Model evaluation for the translation and rotation matrices on the test set was performed using the coefficient of determination(R2).Angle error evaluations for the three-dimensional maxillofacial symmetry reference planes were constructed using the MDGR-Net-associated method and the"ground truth"iterative closest point(ICP)-associated method were conducted on 200 cases in the inter-nal test set and 40 cases in an external test set.Results:Based on testing with the three-dimensional maxillofacial data from the 200-case internal test set,the MDGR-Net model achieved an R2 value of 0.91 for the rotation matrix and 0.98 for the translation matrix.The average angle error on the internal and external test sets were 0.84°±0.55° and 0.58°±0.43°,respectively.The construction of the three-dimensional maxillofacial symmetry reference plane for 40 clinical cases took only 3 seconds,with the model performing optimally in the patients with skeletal Class Ⅲ malocclusion,high angle cases,and Angle Class Ⅲ orthodontic patients.Conclusion:This study proposed the MDGR-Net association method based on intelligent point cloud registration as a novel solution for constructing three-dimensional maxillo-facial symmetry reference planes in clinical dental applications,which can significantly enhance diagnos-tic and therapeutic efficiency and outcomes,while reduce expert dependence.

Objective:To explore the method of obtaining the key parameters of the average value articulator in healthy people based on mandibular movement trajectory data, with a view to providing a reference for the clinical application of the average value articulator.Methods:One hundred healthy volunteers (42 males and 58 females) with individual normal occlusion, aged 18-55 years old, who met the inclusion criteria were recruited from Beijing, and their mandibular movement trajectory data were collected. The left and right sagittal condylar inclination(SCI) and transversal condylar inclination(TCI) were obtained from the values of the articulator parameters which were generated in the mandibular movement analysis system.The SCI and TCI were grouped by gender and calculated separately for the two groups and the overall sample; the gender differences in the two parameters and the differences between the mean values of the two parameters and the average value articulator empirical values (35° for SCI and 15° for TCI) for the overall sample were compared.Results:The differences between SCI (35.8°±7.4°) and TCI [11.2° (11.3°)] in males and the corresponding parameters [35.6°±8.3° and 10.8° (9.5°), respectively] in females were not statistically significant ( t=0.10, P=0.922; Z=-0.60, P=0.552); the overall sample SCI (35.7°±7.9°) did not differ statistically from the average value articulator empirical value ( t=1.23, P=0.221), and the overall sample TCI [10.9° (10.3°)] was significantly smaller than the average value articulator empirical value ( W=5 825.00, P<0.001). Conclusions:The mandibular movement trajectory data of 100 adults with individual normal occlusion in this study shows that the gender factor does not affect the setting of the key parameters of the average value articulator, the SCI of the average value articulator empirical values is appropriate, and the TCI has the possibility of being on the large side. In the clinical use of the articulator to assist in the design of restorations, the parameter values should be rationally adjusted according to the actual situation of the patient′s dentition and mandibular movement.

Objective This study proposes a chairside digital design and manufacturing method for band and loop space maintainers and preliminarily validates its clinical feasibility.Methods Clinical cases of 10 children requiring space maintenance caused by premature loss of primary teeth were collected.Intraoral scan data of the affected children were also collected to establish digital models of the missing teeth.Using a pediatric band and loop space maintainer de-sign software developed by our research team,a rapid personalized design of band and loop structures was achieved,and a digital model of an integrated band and loop space maintainer was ultimately generated.A chairside space maintainer was manufactured through metal computer numerical control machining for the experimental group,whereas metal 3D printing in the dental laboratory was used for the control group.A model fitting assessment was conducted for the space maintainers of both groups,and senior pediatric dental experts were invited to evaluate the clinical feasibility of the space maintainers with regard to fit and stability using the visual analogue scale scoring system.Statistical analysis was also performed.Results The time spent in designing and manufacturing the 10 space maintainers of the experimental group was all less than 1 h.Statistical analysis of expert ratings showed that the experimental group outperformed the control group with regard to fit and stability.Both types of space maintainers met clinical requirements.Conclusion The chairside digital design and manufacturing method for pediatric band and loop space maintainers proposed in this study can achieve same-day fitting of space maintainers at the first appointment,demonstrating good clinical feasibility and significant potential for clinical application.