Three-Dimensional Photography for Evaluating the Effectiveness of Botulinum Toxin Injection for Masseter Hypertrophy.

BACKGROUND: Masseter hypertrophy is a common condition that causes a undesirable square face, and often treated with botulinum toxin type A (BoNTA). Subjective assessments of BoNTA effectiveness vary from physician to patient, necessitating an objective approach for evaluation. This study introduces three-dimensional photography (3DP) for the first time in clinical assessment to evaluate BoNTA treatment for masseter hypertrophy. METHODS: Ten patients received 36U of BoNTA at three injection points on each side masseter muscle. 3DP scanner using Artec Eva® was taken at the first, third, and sixth postoperative months for objective evaluation. Patient's self-perceived prominence, patients self-rated satisfaction, and physicians provided 5-grade scores were the subjective indicators. RESULTS: A significant decrease in left masseter volume at the sixth month (P = 0.002, P = 0.004 at rest and clenching, respectively) was observed. Patient's self-perceived prominence decreased at the first (P = 0.021) and third (P = 0.039) months. Physicians' scores significantly decreased at all postoperative months. No significant changes were noted in the right masseter volume and patients self-rated satisfaction. Patient self-rated satisfaction did not consistently correlate with objective measures, except for left masseter with clenching at the sixth month. CONCLUSION: Three-dimensional photography accurately quantifies facial changes post-BoNTA treatment. Despite objective improvements, patient satisfaction may not align consistently. Reliable assessment tools are crucial in cosmetic surgery to manage expectations and prevent disputes. 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 .

Significantly reducing the presurgical preparation time for anterior pelvic fracture surgery by faster creating patient-specific curved plates.

BACKGROUND: To shorten the preoperative preparation time, reconstruction plates were designed using the computed tomography (CT)-based three-dimensional (3D) medical imaging surgical planning software OOOPDS. In addition, 3D printing was used to generate curved plates for anterior pelvic fracture surgeries. METHODS: This study analyzed two groups with the same 21 patients who underwent surgery for traumatic anterior pelvic ring fractures. In Group 1, the direct reconstruction plates were preoperatively contoured according to the anatomical 3D-printed pelvic model. In Group 2, the fixation plates were contoured according to the 3D printed plate templates, which were created based on the simulated plate templates by the OOOPDS software. The processing time, including the 3D printing time for the pelvic models in Group 1, the 3D printing time for the fixation plate templates in Group 2, and the pre-contouring time for the plates in both groups, was recorded. RESULTS: The mean time of pre-contouring for the curved reconstruction plates in Group 2 was significantly less than in Group 1 (-55 min; P < 0.01). The mean time of 3D printing for the 3D plate template model in Group 2 was significantly less than that for the 3D pelvic model in Group 1 (-869 min; P < 0.01). Experimental results showed that the printing time for the plate pre-contouring and the 3D plate templates could be effectively reduced by approximately 93% and 90%, respectively. CONCLUSION: This method can shorten the preoperative preparation time significantly.

Evaluation of the potential denture covering area in buccal shelf with intraoral scanner.

Background/purpose: The characteristic of soft tissue changes in buccal shelf area during function is unclear. This study aimed for evaluating the potential denture covering area in buccal shelf area in different ranges of mouth opening by a digital approach. Materials and methods: Nineteen qualified dentate participants were enrolled. An intraoral scanner was used to record soft tissue in buccal shelf area in different ranges of mandibular opening, which were maximum intercuspation, 10 mm, 20 mm, and 30 mm of interincisal distance. The experiment was performed by two examiners. The common area of each range was generated within the clinically acceptable denture adaptation range, which was represented as the potential denture covering area. Data were statistically analyzed using descriptive statistic, one-way repeated measure ANOVA, intraclass correlation coefficient (ICC), and the Pearson correlation test. Results: Trends of the mean distance of the potential denture covering area increased from the frenum area to the second premolar and the first molar area then decreased in the second molar area, along with the ranges of mouth opening increased. The distance in the second molar area had drastic percentage changes during the mouth opening. The mean distances changed significantly when the mouth opening increased (P < 0.001). All ICC values of intra-, inter-rater reliability indicated good to excellent reliability. The correlation between the results from two examiners was strong (P < 0.001). Conclusion: The characteristic of the denture covering area posteriorly to the first molar area is inversely proportional in length to ranges of mouth opening.

The rise of 3D Printing entangled with smart computer aided design during COVID-19 era.

During the current Pandemic, seven and a half million flights worldwide were canceled which disrupted the supply chain of all types of goods such as, personal protective gears, medical health devices, raw materials, food, and other essential equipments. The demand for health and medical related goods increased during this period globally, while the production using classical manufacturing techniques were effected because of the lockdowns and disruption in the transporation system. This created the need of geo scattered, small, and rapid manufacturing units along with a smart computer aided design (CAD) facility. The availability of 3D printing technologies and open source CAD design made it possible to overcome this need. In this article, we present an extensive review on the utilization of 3D printing technology in the days of pandamic. We observe that 3D printing together with smart CAD design show promise to overcome the disruption caused by the lockdown of classical manufacturing units specially for medical and testing equipment, and protective gears. We observe that there are several short communications, commentaries, correspondences, editorials and mini reviews compiled and published; however, a systematic state-of-the-art review is required to identify the significance of 3D printing, design for additive manufacturing (AM), and digital supply chain for handling emergency situations and in the post-COVID era. We present a review of various benefits of 3DP particularly in emergency situations such as a pandemic. Furthermore, some relevant iterative design and 3DP case studies are discussed systematically. Finally, this article highlights the areas that can help to control the emergency situation such as a pandemic, and critically discusses the research gaps that need further research in order to exploit the full potential of 3DP in pandemic and post-pandemic future era.

Engineering Additive Manufacturing and Molding Techniques to Create Lifelike Willis' Circle Simulators with Aneurysms for Training Neurosurgeons.

Neurosurgeons require considerable expertise and practical experience in dealing with the critical situations commonly encountered during difficult surgeries; however, neurosurgical trainees seldom have the opportunity to develop these skills in the operating room. Therefore, physical simulators are used to give trainees the experience they require. In this study, we created a physical simulator to assist in training neurosurgeons in aneurysm clipping and the handling of emergency situations during surgery. Our combination of additive manufacturing with molding technology, elastic material casting, and ultrasonication-assisted dissolution made it possible to create a simulator that realistically mimics the brain stem, soft brain lobes, cerebral arteries, and a hollow transparent Circle of Willis, in which the thickness of vascular walls can be controlled and aneurysms can be fabricated in locations where they are likely to appear. The proposed fabrication process also made it possible to limit the error in overall vascular wall thickness to just 2-5%, while achieving a Young's Modulus closely matching the characteristics of blood vessels (~5%). One neurosurgical trainee reported that the physical simulator helped to elucidate the overall process of aneurysm clipping and provided a realistic impression of the tactile feelings involved in this delicate operation. The trainee also experienced shock and dismay at the appearance of leakage, which could not immediately be arrested using the clip. Overall, these results demonstrate the efficacy of the proposed physical simulator in preparing trainees for the rigors involved in performing highly delicate neurological surgical operations.

Passive Magnetic-Flux-Concentrator Based Electromagnetic Targeting System for Endobronchoscopy.

In this paper, we demonstrate an innovative electromagnetic targeting system utilizing a passive magnetic-flux-concentrator for tracking endobronchoscope used in the diagnosis process of lung cancer tumors/lesions. The system consists of a magnetic-flux emitting coil, a magnetic-flux receiving electromagnets-array, and high permeability silicon-steel sheets rolled as a collar (as the passive magnetic-flux-concentrator) fixed in a guide sheath of an endobronchoscope. The emitting coil is used to produce AC magnetic-flux, which is consequently received by the receiving electromagnets-array. Due to the electromagnetic-induction, a voltage is induced in the receiving electromagnets-array. When the endobronchoscope's guide sheath (with the silicon-steel collar) travels between the emitting coil and the receiving electromagnets-arrays, the magnetic flux is concentrated by the silicon-steel collar and thereby the induced voltage is changed. Through analyzing the voltage-pattern change, the location of the silicon-steel collar with the guide sheath is targeted. For testing, a bronchial-tree model for training medical doctors and operators is used to test our system. According to experimental results, the system is successfully verified to be able to target the endobronchoscope in the bronchial-tree model. The targeting errors on the x-, y- and z-axes are 9 mm, 10 mm, and 5 mm, respectively.

Surgical Treatment for Posterior Dislocation of Hip Combined with Acetabular Fractures Using Preoperative Virtual Simulation and Three-Dimensional Printing Model-Assisted Precontoured Plate Fixation Techniques.

BACKGROUND AND PURPOSE: Hip dislocation combined with acetabular fracture remains a challenging condition for orthopedic surgeons. In this study, we utilized a computer-assisted simulation and three-dimensional (3D) printing technology to treat patients with hip dislocation combined with acetabular fracture. We hypothesized that the 3D printing-assisted method would shorten the internal fixation time and surgical time. METHODS: We retrospectively reviewed 16 patients diagnosed with traumatic posterior dislocation of hip combined with acetabular fractures and treated with plate fixation from September 2013 to August 2017. Patients were divided into two groups: (1) traditional method and (2) 3D printing groups. In the traditional method group, the plates were contoured during the surgery, whereas in the 3D printing group, the patient's pelvic computed tomography image was transformed to the 3D medical image software for processing preoperatively. The fracture reduction was simulated by the computer. Thereafter, the 1:1 scale 3D printing model was used to design the surgical plan and contour patient-specific plates preoperatively. RESULTS: The internal fixation time was significantly shorter in the 3D printing group than in the traditional method group (-33 min, P<0.05). The mean operative time was shorter than that in the traditional method group (-43 min). However, blood loss and postoperative radiograph results were similar between the groups. The complication rate was lower in the 3D printing group (2/7) than in the traditional method group (5/9). INTERPRETATION: Computer-assisted simulation with 3D printing technology is a more efficient method for treating hip dislocation combined with acetabular fractures.

Conventional plate fixation method versus pre-operative virtual simulation and three-dimensional printing-assisted contoured plate fixation method in the treatment of anterior pelvic ring fracture.

PURPOSE: Treating pelvic fractures remains a challenging task for orthopaedic surgeons. We aimed to evaluate the feasibility, accuracy, and effectiveness of three-dimensional (3D) printing technology and computer-assisted virtual surgery for pre-operative planning in anterior ring fractures of the pelvis. We hypothesized that using 3D printing models would reduce operation time and significantly improve the surgical outcomes of pelvic fracture repair. METHODS: We retrospectively reviewed the records of 30 patients with pelvic fractures treated by anterior pelvic fixation with locking plates (14 patients, conventional locking plate fixation; 16 patients, pre-operative virtual simulation with 3D, printing-assisted, pre-contoured, locking plate fixation). We compared operative time, instrumentation time, blood loss, and post-surgical residual displacements, as evaluated on X-ray films, among groups. Statistical analyses evaluated significant differences between the groups for each of these variables. RESULTS: The patients treated with the virtual simulation and 3D printing-assisted technique had significantly shorter internal fixation times, shorter surgery duration, and less blood loss (- 57 minutes, - 70 minutes, and - 274 ml, respectively; P < 0.05) than patients in the conventional surgery group. However, the post-operative radiological result was similar between groups (P > 0.05). The complication rate was less in the 3D printing group (1/16 patients) than in the conventional surgery group (3/14 patients). CONCLUSION: The 3D simulation and printing technique is an effective and reliable method for treating anterior pelvic ring fractures. With precise pre-operative planning and accurate execution of the procedures, this time-saving approach can provide a more personalized treatment plan, allowing for a safer orthopaedic surgery.

Pre-operative virtual simulation and three-dimensional printing techniques for the surgical management of acetabular fractures.

PURPOSE: Surgical treatment of acetabular fractures with plate fixation is challenging for orthopaedic surgeons because of variations of the surface curvature and complex fracture patterns of the acetabulum. We present our experience with pre-operative computer-assisted virtual simulation and three-dimensional (3D) printing techniques for the surgical treatment of acetabular fractures, especially in terms of operative time and surgical outcomes. METHODS: Twenty-nine patients with acetabular fractures treated with locking plates were included in this retrospective study (conventional locking plate fixation, n = 17; 3D-printing-assisted precontoured locking plate fixation, n = 12). Fracture types were classified according to the Letournel-Judet classification. Surgical duration, instrumentation time, blood loss, post-operative fracture reduction quality, and complication rates were compared between the two surgical groups. RESULTS: The 3D-printing group had a significantly shorter total surgical duration and instrumentation time for fractures with posterior wall or posterior column involvement (222.75 ± 48.12 and 35.75 ± 9.21 minutes, respectively; P < 0.05) and significantly shorter instrumentation time and less blood loss for fractures with anterior column involvement (43.40 ± 10.92 minutes and 433.33 ± 317.28 mL, respectively; P < 0.05) than those in the control group. The post-operative radiological results (assessed by consensus) were similar for both groups (good/fair: 14/3 vs. 11/1; P = 0.622). The complication rate was lower in the 3D-printing group than in the conventional group (16.67 vs. 29.41%). CONCLUSIONS: The 3D printing is a reliable method for treating acetabular fractures, and can reduce the surgical duration, instrumentation time, and blood loss.

Feasibility and Clinical Effectiveness of Three-Dimensional Printed Model-Assisted Nuss Procedure.

BACKGROUND: The Nuss procedure is a minimally invasive technique for correcting pectus excavatum. We hypothesized that three-dimensional (3D) simulation may shorten operation time and provide better morphologic outcome. This study aimed to demonstrate the feasibility of the 3D model-assisted Nuss procedure and to compare its potential benefits with those of the traditional Nuss procedure. METHODS: We simulated the targeted curvature, length, and planned intercostal space of a metallic bar, based on the preoperative chest computed tomographic images. After the use of a 3D printing technique, a plastic template bar was produced and sterilized. The metallic bar was bent and placed at the planned intercostal space accordingly. The patients' characteristics, total number of pectus bar placement, total operation time, and improvement percentage of Haller indices were compared with patients who underwent the traditional Nuss procedure. RESULTS: A total of 419 patients underwent the Nuss procedure from January 2010 to July 2017 in our hospital, and 357 patients were eligible and enrolled for the following analysis. Fifteen patients underwent 3D simulation. After performing propensity-score matching analysis, the 3D printing group had a shorter operative time (60.36 versus 74.34 minutes, p < 0.001), fewer metallic bar placements (1.00 versus 1.36 bars, p < 0.001), and better improvement percentages in the Haller indices (20.34% versus 10.06%, p < 0.001) compared with the traditional Nuss procedure. CONCLUSIONS: In this preliminary study, 3D-printed model-assisted Nuss procedure may provide benefits of shorter operative time, fewer metallic bar insertions, and comparable morphologic outcome by preoperative simulation.

The Role of Three-Dimensional Printing in the Nuss Procedure: Three-Dimensional Printed Model-Assisted Nuss Procedure.

BACKGROUND: The Nuss procedure is a minimally invasive surgery for pectus excavatum. Success of the Nuss procedure is dependent on a previously bent pectus bar that is shaped to the desired curvature of the chest wall. Traditionally, the size and curvature of the metallic pectus bar are determined by trial and error. Herein, we introduce a novel design method for the metallic pectus bar to optimize the bar curvature and outcome after the Nuss procedure. METHODS: From August 2016 through March 2017, 10 consecutive patients with pectus excavatum underwent the three-dimensional (3D) printed model-assisted Nuss procedure. The computed tomography images were used to generate a 3D thorax model of pectus excavatum. The 3D models of personalized pectus bar curvature were completed by computer-aided design. Herein, we report the demographic data, treatment outcomes, and radiographic findings. RESULTS: All patients with pectus excavatum received one pectus bar insertion. The mean age was 19.80 ± 4.73 years (range, 12 to 26). The mean preoperative Haller index was 3.48 ± 0.35 (range, 3.06 to 3.95). We advantageously utilized preoperative planning; the mean interval change of the Haller index was 20.71% ± 4.63%. With the benefit of 3D printed model simulation, the surgical duration was 59.8 ± 23.2 minutes (range, 32 to 107). No patient had adverse events after operation. CONCLUSIONS: Our initial results revealed that the 3D printed model-assisted Nuss procedure reduces the surgical duration and facilitates an optimal morphological outcome.

Exposure to fine particulate matter causes oxidative and methylated DNA damage in young adults: A longitudinal study.

An increased understanding is needed of the physiological effects and plausible biological mechanisms that link PM2.5 (particulate matter with an aerodynamic diameter below 2.5µm) exposure to mortality and morbidities such as atherosclerosis and respiratory disease. PM2.5 causes carcinogenic health effects. Biomonitoring in humans has suggested that 8-oxo-7, 8-dihydro-2-deoxyguanosine (8-oxodG) and N7-methylguanine (N7-MeG) are correlated with oxidative and methylated DNA damage. Thus, it is meaningful to explore the mechanisms of mutagenesis and carcinogenesis associated with oxidative and methylated DNA damage by simultaneously measuring these two markers. We recruited 72 participants from 2 areas (residential and commercial as well as residential and industrial) in the greater Taipei metropolitan area at baseline. Personal samplers were used to collect 24-hour PM2.5-integrated samples. All participants completed an interview, and blood and urine samples were collected the next morning. All collection procedures were repeated twice after a two-month follow-up period. Urinary 8-oxodG and N7-MeG were assayed as biomarkers of oxidative and methylated DNA damage, respectively. Plasma superoxide dismutase (SOD) and glutathione peroxidase-1 (GPX-1) were measured as biomarkers of antioxidants. Urinary 1-hydroxypyrene (1-OHP) was used as a biomarker of exposure to polycyclic aromatic hydrocarbons (PAHs). The mean PM2.5 level was 37.3µg/m3 at baseline. PM2.5 concentrations were higher during winter than during spring and summer. After adjusting for confounds through a generalized estimating equation (GEE) analysis, N7-MeG was significantly increased by 8.1% (ß=0.034, 95% CIs=0.001-0.068) per 10µg/m3 increment in PM2.5. 8-oxodG levels were positively correlated with N7-MeG according to both cross-sectional and longitudinal analyses, and 1-OHP was significantly associated with increasing 8-oxodG and N7-MeG concentrations. Exposure to PM2.5 increases methylated DNA damage. The mean level of urinary N7-MeG was 1000-fold higher than that of 8-oxodG.