Th-Cell Subsets of Submandibular Lymph Nodes in Peri-Implantitis.

BACKGROUND: Implant surgery is a popular operation in craniomaxillofacial surgery, but the occurrence of peri-implantitis affects the success and survival rate of the implant. Research has found that Th-cell-related cytokines are associated with peri-implantitis. However, the distribution and proportions of Th-cell subsets in submandibular lymph nodes' immune environments during the progression of peri-implantitis remain unclear. METHODS: Forty-eight rats were randomly divided into 4 groups: the control group, the 1-week ligation peri-implantitis induction (Lig 1w) group, the Lig 2w group, and the Lig 4w group (n=12). Ligation was maintained for different times to induce peri-implantitis 4 weeks after implantation. Inflammation and bone resorption were examined by clinical probing and micro-CT. The submandibular lymph nodes were harvested for quantitative real-time polymerase chain reaction and flow cytometry to obtain the Th-cell profiles. RESULTS: With increasing ligation time, more redness and swelling in the gingiva and more bone resorption around the implant were observed (P<0.05). The proportions of Th1 and Th17 cells increased, the proportion of Th2 cells decreased, and the proportion of Treg cells first increased and then decreased in the lymph nodes (P<0.05). CONCLUSIONS: This study provided a preliminary characterization of the temporal distribution of Th cells in lymph nodes of peri-implantitis. Persistent elevation of Th1 and Th17 proportions and decrease of Treg proportion may be the cause of bone resorption in peri-implantitis. Lymphatic drainage may be a bridge between craniomaxillofacial diseases and systemic diseases. Early immune support against T cells may be a potential therapeutic idea for the prevention of implant failure and the potential risk of systemic disease.

Minimally Invasive 980 nm Laser-Assisted Lipolysis and Skin Tightening on Lower Eyelids of Asian Patients.

OBJECTIVE: The present study aimed to evaluate the effectiveness of minimally invasive 980 nm laser-assisted lipolysis and skin tightening in lower eyelid blepharoplasty of Asian patients. METHODS: Patients with mild and moderate degree of eyebags underwent 980 nm laser-assisted lipolysis via lower eyelid stab incision between December 2017 and December 2019. Evaluation criteria was reviewed by photographs taken preoperatively and 6 months postoperatively in accordance with guidelines of Global Aesthetic Improvement Scale, the patient's perspective from the questionnaire with the perception of reduction in eyebags size, the average perception of improvement in skin tightening, and the patient overall satisfaction, all with a score of 1 to 5 (5 being the most noticeable and very satisfied) and complications such as dyspigmentation, hematoma, prolonged edema, skin bump and thermal burn were documented as well. RESULTS: A total of 178 cases with 137 women and 41 men (age range from 23 to 50 years) were included. Total energy of 1200 J to 2000 J was delivered to both eyebags at 6 to 10 W. They were followed up for at least 6 months. A total of 166 patients (93.26%) revealed an improvement in Global Aesthetic Improvement Scale, with the 12 patients (6.74%) complaint no change 6 month postoperatively. Perception of improvement in eye bag protrusion scored 4.39 ± 0.59, improvement in skin tightening scored 4.42 ± 0.58 and the overall patient's satisfaction scored 4.59 ± 0.53. The patients' average recovered swelling from 4.35 ± 2.3 days. There were 5 patients (2.8%) with dyspigmentation, 3 patients (1.69%) with prolonged edema and 2 patients (1.12%) with skin bump and none of the patients had thermal burn. All of them resolve after 6 months of follow up. CONCLUSION: Patients with mild to moderate degree of eyebags who resist surgery are good candidates for laser-assisted lower eyelid blepharoplasty.

Efficacy of extended view totally extra peritoneal approach versus laparoscopic intraperitoneal on lay mesh plus for abdominal wall hernias: a single center preliminary retrospective study.

BACKGROUND: Laparoscopic minimally invasive surgery has become the primary treatment for ventral hernias. The laparoscopic intraperitoneal on lay mesh (IPOM) plus approach for abdominal wall hernias is the most used procedure, while extended view totally extraperitoneal (e­TEP) repair is a newer option. This study aimed to compare the effectiveness and complications of the 2 procedures for abdominal wall hernias repair. METHODS: This was a retrospective and comparative single-center study done at The Second Clinical Medical College, Jinan University Hospital (Shenzhen People's Hospital), Shenzhen, China. The study included patients with a 2 to 6 cm abdominal wall defect who underwent hernia repair from January 2022 to December 2022. Patients' baseline characteristics, hernia features, operative time, blood loss, postoperative pain level, and total hospitalization expenses were extracted from the medical records and compared between patients who underwent the IPOM plus and e-TEP repair. RESULTS: A total of 53 patients were included: 22 in the e-TEP group and 31 in IPOM plus group. Patient demographic characteristics were similar between the 2 groups. The operation time of the e-TEP groups was significantly longer than the IPOM plus (98.5 ± 10.7 min vs. 65.9 ± 7.3 min, P < 0.01). Postoperative pain levels (VAS; visual analog scale) (4.2 ± 0.9 vs. 6.7 ± 0.9, P < 0.01), analgesic requirements (Tramadol) (25.0 ± 37.0 mg vs. 72.6 ± 40.5 mg, P < 0.01), length of hospital stay (1.2 ± 0.5days vs. 2.2 ± 0.6days, P < 0.01), and total hospitalization expenses (19695.9 ± 1221.7CNY vs. 35286.2 ± 1196.6CNY, P < 0.01) were significantly lower in the e-TEP group. The mean intraoperative blood loss was similar between the 2 groups. No postoperative complications were observed in either group. CONCLUSION: The e-TEP approach for abdominal wall hernias appears to be better than IPOM plus with respect to postoperative pain levels(VAS: 4.2 ± 0.9 vs. 6.7 ± 0.9, P < 0.01), analgesic requirements(25.0 ± 37.0 mg vs. 72.6 ± 40.5 mg, P < 0.01), length of hospital stay(1.2 ± 0.5days vs. 2.2 ± 0.6days, P < 0.01), and hospitalization costs (19695.9 ± 1221.7CNY vs. 35286.2 ± 1196.6CNY, P < 0.01).

A Study on the Correlation of Big 5 Personality Traits in Asians With Facial Contour Surgery.

PURPOSE: The purpose of this study is to explore the present situation and related factors of big 5 personality in Asian patients with facial contour surgery and to provide experience for clinical individualized medical care. METHODS: Total 235 patients with facial contour surgery were selected in this study. The Neo Five-factor Inventory was used to investigate them. RESULTS: The scores of conscientiousness and openness in the Neo Five-factor Inventory were higher than others, whereas neuroticism score was lowest in patients with facial contour surgery. The scores of extroversion and agreeableness were in the middle level. Among the big 5 personality the age, educational background, self-rated personality, the only child in a family and other cosmetic surgery history had significant differences in patients. CONCLUSIONS: Patients with facial contour surgery for different sex, different marital status, different body mass index, there is no significant difference in the big 5 personality through this study. However, older patients had higher score for conscientiousness, patients with higher educational background had higher scores in openness and patients with introverted personality had higher neuroticism score. The authors should take individualized personality traits during perioperative care to help the patients to establish a correct and healthy esthetic concept, as well as postoperative body image concept, to build their self-confidence and social competitiveness.

Exploration of Novel Genetic Evidence and Clinical Significance Into Hemifacial Microsomia Pathogenesis.

The authors browsed through past genetic findings in hemifacial microsomia along with our previously identified mutations in ITGB4 and PDE4DIP from whole genome sequencing of hemifacial microsomia patients. Wondering whether these genes influence mandibular bone modeling by regulation on osteogenesis, the authors approached mechanisms of hemifacial microsomia through this investigation into gene knockdown effects in vitro. MC3T3E1 cells were divided into 5 groups: the negative control group without osteogenesis induction or siRNA, the positive control group with only osteogenesis induction, and 3 gene silenced groups with both osteogenesis induction and siRNA. Validation of transfection was through fluorescence microscopy and quantitative real-time Polymerase chain reaction on knockdown efficiency. Changes in expression levels of the 3 genes during osteogenesis and impact of Itgb4 and Pde4dip knockdown on osteogenesis were examined by quantitative real-time Polymerase chain reaction, alkaline phosphatase, and alizarin red staining. Elevation of osteogenic genes Alpl, Col1a1, Bglap, Spp1, and Runx2 verified successful osteogenesis. Both genes were upregulated under osteogenic induction, while they had different trends over time. Intracellular fluorophores under microscope validated successful transfection and si-m-Itgb4_003, si-m-Pde4dip_002 had satisfactory knockdown effects. During osteogenesis, Pde4dip knockdown enhanced Spp1 expression (1.95±0.13 folds, P =0.045). The authors speculated that these genes may have different involvements in osteogenesis. Stimulated expression of Spp1 by Pde4dip knockdown may suggest that Pde4dip inhibits osteogenesis.

Discrepancy in Mandibular Medullary Cavity on Different Sides: More Hints Towards Understanding Hemifacial Microsomia.

The authors attempt to approach hemifacial microsomia with macroscopic techniques and look for a link between clinical manifestations with pathogenesis. In this study, for the first time mandibular medullary cavities as essential parts of the mandible were intravitally measured based on the 3-dimensional models. A total of 153 patients were included. The 3-dimensional models of patients' mandibles were reconstructed and medullary cavity volumes (mm 3 ) were measured. The ratio of medullary cavity volume to mandible volume was calculated to determine the proportion of the marrow in the bone. Statistical significance was found in mandible volumes ( P <0.001) and medullary cavity volumes ( P <0.001) on different sides. Medullary cavity volumes were significantly related to mandible volumes on both sides (both P <0.001). Medullary cavity volumes on the nonaffected and affected side were both in correlation with age but in different degrees ( r =0.214, P =0.008 versus r =0.170, P =0.036). The ratios of medullary cavity volume and the mandible were significantly different ( P <0.001) on 2 sides. The volume ratio on the nonaffected side correlated to age while this correlation did not exist on the affected side ( r =0.195, P =0.016 versus r =0.129, P =0.112). A smaller medullary cavity found on the affected side could lead to a reduced amount of bone marrow cells and consequently reduced osteogenic and hematopoietic potential. This could result in abnormal bone formation on the affected side of mandible. Proportions of marrow in bone on the affected side irrelevant to patients' ages signify a poorer potential of expansion. This may explain a higher reluctancy of growth in affected mandibular sides.

The Feasibility of Electromagnetic Navigation Technique to Achieve Preoperative Plan in Mandibular Angle Osteotomy.

BACKGROUND: In contrast to the most commonly used optical navigation system, electromagnetic navigation has huge potential in operations with a narrow field. The purpose of this experiment was to test and confirm whether the electromagnetic navigation method the authors developed for mandibular angle osteotomy (MAO) met clinical requirements. METHODS: Using a dental splint that could be repeatedly mounted on teeth, registration between surgical plan and actual field was performed automatically. RESULTS: Navigation of MAO was first performed on 10 mandibular models. The position precision measured using a coordinate measuring machine was 1.30±0.61 mm. Then, a navigation experiment was performed on 4 patients. Accuracy in actual operation measured by the NDI pointing sensor was 1.89±0.76 mm. Our noninvasive automatic registration process reduced the surgical exposure time and eliminated the bias of the manual selection of registration points. CONCLUSIONS: This preliminary study confirmed the feasibility of the electromagnetic navigation technique in terms of both applicability and accuracy in MAO surgery.

Comparison of Piezosurgery and Conventional Osteotomy for Orbital Hypertelorism Surgical Correction.

The purpose of this study was to compare the safety and effect of piezosurgery with conventional osteotomy in a box-shifting procedure for orbital hypertelorism (ORH) correction surgery. This study retrospectively analyzed the clinical record of 10 ORH patients aged from 5 to 12 years, and they were second-degree ORH with an interorbital distance (IOD) of 35 to 37.8 mm. Three of them received the osteotomy with piezosurgery (the piezosurgery group), whereas the other 7 patients received osteotomy with the conventional osteotomy method (the control group). They were compared with age and preoperative IOD. All the patients' IOD was effectively improved to normal range after the surgery. The results showed that the application of piezosurgery did not prolong the surgery time (piezosurgery group: 8.3±0.5 hours; control group: 8.7±1.4 hours, P =0.68). Furthermore, the patients in the piezosurgery group had less drainage volume (piezosurgery group: 79.1±12 mL; the control group: 170±41.3 mL, P =0.0065) and shorter postoperative hospital stay (piezosurgery group: 8.3±2.0 d; control group: 12.43±2.29 d, P =0.029). There were 2 patients who had wound infections, 1 in the piezosurgery group and 1 in the control group, respectively. However, 1 patient in the control group suffered from cerebrospinal fluid leakage. On the basis of the results, the application of piezosurgery benefited the patients on a better and smoother recovery course with less drainage and shorter hospital stays. The advantages of piezosurgery are the fine and precise osteotomy and the protection for soft tissue, which make it a comparatively safe and effective tool for craniofacial surgery, especially for young patients.

Preliminary Application Research of 3D Bioprinting in Craniofacial Reconstruction.

INTRODUCTION: In recent years, 3-dimensional (3D) printing has been widely used in regenerative medicine research and other fields because of its ability to customize macroscopic morphology and precisely control microstructure. Polymer scaffolds are 1 of the commonly used 3D bioprinting materials for defect repair and have recently been a research focus. Our article explored the bone-formation accelerating effect of 3D-printed porous scaffold Poly(glycerol sebacate) [PGS] in the critical bone defect of an enhancing rabbit mandibular model. Also, we overview and summarize the classification of 3D bioprinting materials and prospects for their various application scenarios in craniofacial reconstruction surgery. MATERIALS AND METHODS: A PGS elastomer scaffold was prepared by polymerizing equimolar amounts of sebacic acid and glycerol using a biological 3D printer. Six male New Zealand white rabbits were prepared (3 for the control group and 3 for the PGS group), each weighing 3 kg. Osteotomy was performed at the anterior edge of the ascending ramus of the mandible with a bone saw to open the 8 mm defect. Defects of the control group were empty, and defects of the PGS group were put into 8 mm-wide PGS elastomer scaffolds. The rabbits were euthanized 6 weeks after the operation, and the postoperative mandibles were collected. Information (presence or absence of pus from infection, nonunion, degree of macroscopic bone healing) was recorded, and the skeletal tissue was fixed in a paraformaldehyde solution. RESULTS: The mandible on the enhanced side was significantly longer than that on the opposite side, and the contralateral incisor was hyperplasia. The mandibles of rabbits in each group healed well, and there was no obvious local infection and purulence. The gross specimen appearance showed that both ends of the defect were connected. When comparing the reconstructed mandibles of the two groups, it is apparent that the width and thickness of the new bone in the PGS group were significantly better than that in the control group. CONCLUSIONS: This article verifies the effect of 3D polypore PGS scaffolds in animal craniomaxillofacial bone defects and introduces various application scenarios of 3D printing materials in craniomaxillofacial reconstruction surgery. There are quite good application prospects for 3D bioprinting in animal experiments and even clinical treatment of craniofacial defects.

Three-dimensional Printing Technologies in Craniofacial Plastic Surgery: An Institutional Experience.

Rapid developments in 3-dimensional(3D) printing technologies in craniofacial plastic surgery have provided a new treatment modality for patients. In this article, we intend to share our institution's experience using 3D printing in 3 modes-namely, 3-dimensional printing for manufacturing contour models, guides, and implants. Fifty-nine patients were enrolled in our study between September 2009 and September 2021. Among the 3D printing-assisted technologies, 41 cases were used for congenital malformations, 82 for trauma repair, and 112 for cosmetic surgery. Preoperative design and postoperative data were compared and analyzed based on imaging data. In craniofacial plastic surgery, all patients had excellent postoperative objective bone measurements close to the preoperative design and improved esthetic appearance. Our survey of postoperative satisfaction showed that patients were quite satisfied with the surgery, especially concerning congenital deformities. Rapid prototyping 3-dimensional printing technology provides a practical and anatomically accurate means to produce patient-specific and disease-specific translational tools. These models can be used for surgical planning, simulation, and clinical evaluation. Expanding this technology in craniofacial plastic surgery will provide adequate assistance to practitioners and patients.

Radiomics and Artificial Intelligence Study of Masseter Muscle Segmentation in Patients With Hemifacial Microsomia.

BACKGROUND: Hemifacial microsomia (HFM) is one of the most common congenital craniofacial condition often accompanied by masseter muscle involvement. U-Net neural convolution network for masseter segmentation is expected to achieve an efficient evaluation of masseter muscle. METHODS: A database was established with 108 patients with HFM from June 2012 to June 2019 in our center. Demographic data, OMENS classification, and 1-mm layer thick 3-dimensional computed tomography were included. Two radiologists manually segmented masseter muscles in a consensus reading as the ground truth. A test set of 20 cases was duplicated into 2 groups: an experimental group with the intelligent algorithm and a control group with manual segmentation. The U-net follows the design of 3D RoI-Aware U-Net with overlapping window strategy and references to our previous study of masseter segmentation in a healthy population system. Sorensen dice-similarity coefficient (DSC) muscle volume, average surface distance, recall, and time were used to validate compared with the ground truth. RESULTS: The mean DSC value of 0.794±0.028 for the experiment group was compared with the manual segmentation (0.885±0.118) with α=0.05 and a noninferiority margin of 15%. In addition, higher DSC was reported in patients with milder mandible deformity ( r =0.824, P <0.05). Moreover, intelligent automatic segmentation takes only 6.4 seconds showing great efficiency. CONCLUSIONS: We first proposed a U-net neural convolutional network and achieved automatic segmentation of masseter muscles in patients with HFM. It is a great attempt at intelligent diagnosis and evaluation of craniofacial diseases.

Feasibility of a Robot-Assisted Surgical Navigation System for Mandibular Distraction Osteogenesis in Hemifacial Microsomia: A Model Experiment.

This study aimed to investigate the feasibility and accuracy of osteotomy and distractor placement using a robotic navigation system in a model surgical experiment of mandibular distraction osteogenesis for hemifacial microsomia. Imaging data from 5 patients with Pruzansky-Kaban type II (IIa: 4; IIb: 1) mandibular deformities were used to print 3D models for simulated mandibular distraction osteogenesis. In the experimental group, a robot-assisted surgical navigation system was used to perform the surgery under robotic guidance following registration, according to the preoperative design. Conventional surgery was performed in the control group, in which the operation was based on intraoperative estimations of the preoperative design by experienced surgeons. The accuracies of the osteotomy and distractor placement were assessed based on distance and angular error. Osteotomy accuracy was higher in the experimental group than in the control group, and the distance error ( t =9.311, P <0.001) and angular error ( t =5.385, P =0.001) were significantly reduced. The accuracy of distractor placement was also significantly higher in the experimental group, while the distance error ( t =3.048, P =0.016) and angular error ( t =3.524, P =0.024) were significantly reduced. The present results highlight the feasibility of robot-assisted distraction osteogenesis combined with electromagnetic navigation for improved surgical precision in clinical settings.

Advances in Robot-Assisted Surgery for Facial Bone Contouring Surgery.

Since our team reported the application of robot-assisted surgery in facial contouring surgery in 2020, further clinical trials with large samples have been conducted. This paper will report the interim results of a single-center, large-sample randomized controlled trial of the first robot developed by our team for facial contouring surgery. Meanwhile, this research field will be systematically reviewed and prospected.

Design of a Dual-Mode Multispectral Filter Array.

Multispectral imaging is valuable in many vision-related fields as it provides an additional modality to observe the world. Cameras equipped with multispectral filter arrays (MSFAs) are typically impractical for everyday use due to their intractable demosaicking and chromatic reproduction processes, which restrict their applicability beyond academic research. In this work, a novel MSFA design is proposed to enable dual-mode imaging for multispectral cameras. In addition to a conventional multispectral image, the camera is also able to produce a Bayer-formed RGB image from a single shot by grouping and merging adjacent pixels in the proposed MSFA, making it suitable for scenarios where display-ready RGB images are required. Furthermore, a two-stage optimization scheme is implemented to jointly optimize objective functions for both imaging modes. The evaluation results on multiple datasets suggest that the proposed MSFA design is able to simultaneously achieve competitive spectral reconstruction accuracy compared to elaborate multispectral cameras and chromatic accuracy compared to commercial RGB cameras.

Complications Following Facial Injection of Growth Factor Solution.

OBJECTIVE: Topical injection of growth factor (GF) for facial rejuvenation is unauthorized, but it is commonly performed in China, leading to emerging and challenging complications. The purpose of this study is to investigate the clinical, imaging, and histopathologic characteristics of complications caused by facial GF injection, as well as their treatments and outcomes. METHODS: We performed a retrospective single-centered case series study on consecutive patients who were treated for complications following facial injection of GF. The primary outcome was the recurrence over follow-up period. The secondary outcomes were the subjective evaluations of the facial aesthetic, symptomatic, and psychological improvements using the Global Aesthetic Improvement Scale (GAIS) and a patient-reported outcome measurement (PROM). Kaplan-Meier analysis and log-rank test were performed to investigate the recurrence. RESULTS: A total of 32 females with an average age of 42.6 ± 9.4 years were included. Most patients received GF injections in non-medical institutes such as beauty spas and presented with uncontrollable soft tissue hyperplasia, diffuse subcutaneous swelling, and skin redness. Ultrasonography showed heterogeneous hypoechoic or echogenic areas in a thickened and disorganized subcutaneous tissue hierarchy. MRI showed flaky isointensive or hypointensive signals on T1WI and hyperintensive signals on T2WI. 37.5% patient underwent triamcinolone acetonide injection, whereas 62.5% patients underwent surgical interventions. Lipoma-like hyperplastic tissue was found during surgery. HE staining confirmed intramuscular lipoma and fibrolipomatous tissue hyperplasia. Recurrence was found in 37.5% patients over a median follow-up of 6 months. KM curves and log-rank test demonstrated no significant difference in the recurrence between patients who underwent nonsurgical or surgical interventions (p = 0.77). GAIS and PROM scores indicated substantial aesthetic, symptomatic, and psychological improvements in 70%, 91.7%, and 75% patients, respectively. CONCLUSIONS: Both surgical and nonsurgical interventions are feasible and effective treatment options for GF-induced complications. Although recurrence rate was relatively high, aesthetic, symptomatic, and psychological improvements were achieved in most patients. We developed a workflow that might help diagnose and treat complications following unknown dermal filler injections. LEVEL OF EVIDENCE IV: 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 .

Efficacy of early laparoscopic cholecystectomy compared with percutaneous transhepatic gallbladder drainage in treating acute calculous cholecystitis in elderly patients.

BACKGROUND: Acute calculous cholecystitis is a common acute disease in elderly patients. This study aimed to evaluate the efficacy of early laparoscopic cholecystectomy (ELC) compared to percutaneous transhepatic gallbladder drainage (PTGD) for treating acute calculous cholecystitis in elderly patients. METHODS: This retrospective study compared the clinical outcomes of two groups of elderly patients treated with ELC (group A) and PTGD (group B) from January 2018 to December 2021. Preoperative clinical characteristics and postoperative treatment outcomes were analyzed for both groups. RESULTS: There were no statistically significant differences in preoperative clinical characteristics between the ELC and PTGD groups. ELC took longer to perform (69.8 ± 15.9 min vs. 29.6 ± 5.3 min, p < 0.001) but resulted in a significantly shorter duration of pain (1.9 ± 0.9 days vs. 3.9 ± 1.0 days, p < 0.001) and hospital stay (6.3 ± 2.5 days vs. 9.9 ± 3.6 days, p < 0.001), and a lower rate of sepsis (3.4% vs. 16.9%, p < 0.019). Time to soft diet was faster in the ELC group (1.5 ± 0.9 days vs. 3.0 ± 1.6 days, p < 0.001). Fewer patients in the ELC group experienced surgical reintervention than in the PTGD group (0% vs. 5.6%, p = 0.043). The incidence of postoperative complications and readmission rates in the ELC group were significantly lower than those in the PTGD group (ELC, 3.6%; PTGD, 25.4%, p = 0.001). CONCLUSIONS: ELC is an effective treatment option for acute calculous cholecystitis in elderly patients, and has the added benefits of low postoperative complication rates, rapid recovery, shorter duration of pain, and excellent curative effects as compared to PTGD.

Study of display white point based on mixed chromatic adaptation.

In this study, the settings of the display white points were investigated, which presented the color appearance matched with a neutral surface as observed in the state of mixed chromatic adaptation. A psychophysical experiment was conducted under 20 illumination and viewing conditions via successive binocular color matching. It is discovered that the metameric light sources have generally equivalent effects on the observers' adaptation states and the resulting white points. The correlated color temperature (CCT) of the illumination and the adapting luminance, both with a significant influence on the mixed chromatic adaptation, exhibit a positive and a negative relation to the white point CCT, respectively. The immersive illumination affects the white point through the adaptation ratio and the baseline illuminant. Finally, the experimental results were verified to be predictable with an amended mixed chromatic adaptation model, which produced a mean chromaticity error of only 0.0027 units of CIE 1976 u'v'.

Application of Augmented Reality Navigation in Treatment With Fibrosis Dysplasia.

OBJECTIVE: In order to reduce the possibility of accidental injury to neurovascular and important tissues, this research conduct preoperative design and intraoperative guidance for fibrous dysplasia through augmented reality technology. METHODS: Five patients with fibrous dysplasia were selected for three-dimensional (3D) Computed Tomography (CT) scan and 3D model was reconstructed. Considering the navigation plan was comprehensively, the guide plate (composed of card groove, connector, and fixator) was designed and 3D printed. Threedimensional software was used to unify the coordinates of the surgical plan and the guide plate, and the relative position was fixed. Then, the virtual and real overlapping registration is completed on the physical model. Pattern recognition technology is used to identify pre-defined markers in the video images before operation. Finally, the registration results are superimposed into the surgical field of vision to guide and remind surgeons. RESULTS: In this study, the navigation based on augmented reality technology was used in the surgical treatment of 5 cases patients with fibrous dysplasia. The 3D navigation information was displayed in real time in the operative field. The operation was accurate and the postoperative effect was good. CONCLUSIONS: This paper introduces an effective visual navigation surgical method in treatment with fibrous dysplasia. The augmented- reality based navigation system achieves individualized precise treatment by displaying 3D navigation directly in the surgical field. It is an effective auxiliary method for future research on craniofacial surgery.

Assessment of Robot-Assisted Mandibular Contouring Surgery in Comparison With Traditional Surgery: A Prospective, Single-Center, Randomized Controlled Trial.

BACKGROUND: Few clinical studies on robot-assisted surgery (RAS) for mandibular contouring have been reported. OBJECTIVES: The aim of this study was to follow the long-term effectiveness and safety of RAS for craniofacial bone surgery. METHODS: This small-sample, early-phase, prospective, randomized controlled study included patients diagnosed with mandibular deformity requiring mandibular contouring surgery. Patients of both genders aged 18 to 30 years without complicated craniofacial repair defects were enrolled and randomly assigned in a 1:1 ratio by a permuted-block randomized assignments list generated by the study statistician. The primary outcomes were the positioning accuracy and accuracy of the osteotomy plane angle 1 week after surgery. Surgical auxiliary measurement index, patient satisfaction scale, surgical pain scale, perioperative period, and complications at 1 week, 1 month, and 6 months after surgery were also analyzed. RESULTS: One patient was lost to follow-up, resulting in a total of 14 patients in the traditional surgery group and 15 in the robot-assisted group (mean [standard deviation] age, 22.65 [3.60] years). Among the primary outcomes, there was a significant difference in the positioning accuracy (2.91 mm vs 1.65 mm; P < 0.01) and angle accuracy (13.26º vs 4.85º; P < 0.01) between the 2 groups. Secondary outcomes did not significantly differ. CONCLUSIONS: Compared to traditional surgery, robot-assisted mandibular contouring surgery showed improved precision in bone shaving, as well as higher safety.

Fractal analysis of rat dermal tissue in the different injury states.

Scar formation and chronic ulcers can develop following a skin injury. They are the result of the over- or underproduction of collagen. It is very important to evaluate the quality and quantity of the collagen that is produced during wound healing, especially with respect to its structure, as these factors are very important to a complicated outcome. However, there is no standard way to quantitatively analyse dermal collagen. As prior work characterised some potentially fractal properties of collagen, it was hypothesised that collagen structure could be evaluated with fractal dimension analysis. Small-angle X-ray scattering technology (SAXS) was used to evaluate the dermis of rats exposed to graft harvest, burn, and diabetic pathologic states. It was found that almost all collagen structures could be quantitatively measured with fractal dimension analysis. Further, there were significant differences in the three-dimensional (3-D) structure of normal collagen versus that measured in pathologic tissues. There was a significant difference in the 3-D structure of collagen at different stages of healing. The findings of this work suggest that fractal analysis is a good tool for wound healing analysis, and that quantitative collagen analysis is very useful for assessing the structure of dermal collagen.