Comparison of Patient-Specific Condylar Positioning Devices and Manual Methods in Orthognathic Surgery: A Prospective Randomized Trial.

BACKGROUND: This study investigated whether patient-specific condylar positioning devices (CPDs) are beneficial compared to the conventional manual positioning of the condyles. METHODS: In this prospective, randomized trial, patients undergoing orthognathic surgery with a bilateral sagittal split osteotomy of the mandible were included. The ascending ramus was positioned with computer-aided designed and computer-aided manufactured (CAD/CAM) patient-specific devices in the CPD group and manually in the control group. Postoperatively, cone-beam computed tomography (CBCT) was performed to align the virtually planned position with the postoperative result. RESULTS: Thirty patients were enrolled in the study, with 14 randomized to the CPD group and 16 to the control group. In the CPD group, the ascending ramus differed in the postoperative CBCT scan from the virtually planned position by 0.8 mm in the left/right, 0.8 mm in the front/back, and 1.3 mm in the cranial/caudal direction. The corresponding control-group values were 1.1 mm, 1.3 mm, and 1.6 mm. CPD and controls differed significantly for the left/right movement of the rami (p = 0.04) but not for the other directions or rotations (p > 0.05). CONCLUSIONS: The results demonstrate that both methods are accurate, and postoperative results matched the virtually planned position precisely. It can be assumed that the described CPDs are beneficial when a condylar position different from the preoperative is desired.

Sensitive riboflavin sensing using silver nanoparticles deposited onto screen-printed electrodes via controlled-energy spark discharges.

In this work, we elaborated the graphite screen-printed electrodes (SPEs) modification with metal nanoparticles formed as a result of spark discharges produced between a metal wire electrode and SPE that are connected to an Arduino board-based DC high voltage power supply. This sparking device allows, on the one hand, the toposelective formation of NPs of controlled dimensions through a direct and liquid-free approach, and on the other hand, controls the number and energy of the discharges delivered to the electrode surface during a single spark event. This way, the potential damage to the SPE surface by the action of heat evolved during the sparking process is considerably minimized compared with the standard setup in which each spark event consists of multiple electrical discharges. Data demonstrated that the sensing properties of the resulting electrodes are significantly improved compared with those achieved when conventional spark generators are employed, as demonstrated for silver-sparked SPEs that exhibit enhanced sensitivity to riboflavin. Sparked AgNp-SPEs were characterized using scanning electron microscopy and voltammetric measurements in alkaline conditions. The analytical performance of sparked AgNP-SPEs was evaluated by various electrochemical techniques. Under optimum conditions, the detection range for DPV was from 1.9 (LOQ) to 100 nM riboflavin (R2 = 0.997), while a limit of detection (LOD, S/N 3) of 0.56 nM was achieved. The analytical utility is demonstrated for the determination of riboflavin in the real matrices of B-complex pharmaceutical preparation and an energy drink.

Efficacy and safety of a new disposable percutaneous positioning device invented to facilitate the precision of percutaneous core needle lung biopsies: a prospective, open and randomized controlled study.

BACKGROUND: A new disposable percutaneous positioning device was developed which permits adjustment of the fixing puncture angle while performing a percutaneous core needle lung biopsy (CNLB). The aim of the study was to explore the positioning accuracy and clinical safety of the new device during CT-guided percutaneous CNLB. METHODS: A prospective, open and randomized controlled study with two parallel groups was conducted on 150 patients with pulmonary nodules between July 1, 2018 and June 30, 2019 including 101 males and 49 females who were divided (allocation ratio: 1:1) into a standard CNLB group without the percutaneous positioning device (control, n=75) and a new percutaneous positioning device group combined with CNLB (experimental, n=75). The efficacy was determined by the success rate of reaching the target location on the first percutaneous attempt, the number of CT scans performed and the time required for successful puncture positioning. Safety evaluations included complications related to percutaneous surgery and the new positioning device. RESULTS: The success rate of reaching the target location on the first percutaneous attempt in the experimental group was significantly higher than in the control group [96.0% (72/75) vs. 42.7% (32/75), P<0.001]. Patients in the experimental group received 3.05±0.28 times CT scans on average for successful percutaneous positioning, which was significantly lower than for the control group (3.95±1.03) (P<0.001). The time required to complete the percutaneous positioning was significantly lower in the experimental group compared to the control group (8.73±3.11 vs. 12.79±4.55 min, P<0.001). There was no significant difference in percutaneous-related complications between the two groups [48.0% (36/75) vs. 61.3% (46/75), P=0.101], except that the bleeding rate in the experimental group was lower than in the control group [26.7% (20/75) vs. 46.7% (35/75), P=0.032]. CONCLUSIONS: The use of the optimized percutaneous technology with the new positioning device significantly improved the accuracy and precision of percutaneous lung biopsies. TRIAL REGISTRATION: ChiCTR-INR-17010322.

Efficacy of the Epidural Positioning Device® in optimizing the acoustic target window for neuraxial needle placement in term pregnancy.

BACKGROUND: Neuraxial anesthesia can be challenging in obstetric patients due to the gravid uterus interfering with patient positioning. Ultrasound is commonly used in obstetric anesthesia to facilitate neuraxial needle placement. Some positioning maneuvers facilitate the ultrasound visualization of structures and the placement of neuraxial needles, but the Epidural Positioning Device (EPD) has yet to be evaluated. OBJECTIVES: Our goal was to evaluate whether the use of the EPD increased the acoustic target window in the lumbar area of pregnant patients. We hypothesized that the application of the EPD would increase the measured lengths of the paravertebral longitudinal ligament (PLL), the interlaminar distance (ILD) and the ligamentum flavum (LF). METHODS: Lumbar ultrasonography was performed on 29 pregnant women having an elective cesarean delivery. Two anesthesiologists independently scanned the L3-4 right paramedian space, using a curvilinear ultrasound transducer, in two positions for each patient: traditional sitting with lumbar flexion and sitting with use of the EPD for lumbar flexion. The PLL, ILD and LF lengths were measured using the ultrasound caliper software and recorded, with the anesthesiologists blinded to the results. Patients were asked to rate their comfort in both positions. RESULTS: There were no significant differences between the measured lengths of the PLL, ILD and LF in the two positions. Patient comfort was significantly higher with use of the EPD (OR 10, 95% CI 2.4 to 88). CONCLUSION: Although the application of an EPD did not improve the paramedian acoustic target area in term parturients, greater patient comfort might facilitate needle placement.

Auxiliary positioning of a new positioning device in internal fixation of femoral neck fracture with cannulated screws / 中国组织工程研究

BACKGROUND: At present, the application of intelligent positioning devices such as orthopedic robots and computer navigation systems in closed reduction surgery for femoral neck fractures is gradually developed, and grassroots hospitals still need a cheap auxiliary positioning device. OBJECTIVE: To investigate the effect of a Kirschner wire positioning device for assisted localization in internal fixation of femoral neck fracture with cannulated screws. METHODS: Fifty-four cases of femoral neck fracture treated in Binzhou Medical University Hospital from February 2016 to March 2018 were retrospectively analyzed. The patients were allocated into the two groups, 28 patients who received traditional cannulated screws internal fixation were in the traditional group, and 26 patients who received assisted localization internal fixation with cannulated screws were in the assisted localization group. The angle, direction and distance of the Kirschner wire could be quantified and fine-tuned, assisted with accurate positioning, and the placement of the cannulated screws was guided. Clinical and imaging data were compared between two groups. RESULTS AND CONCLUSION: (1) All patients received surgery successfully. No intraoperative complications such as vascular or nerve injury occurred. Postoperative image showed good fracture reduction, cannulated screw distribution, angle and position. (2) The operation time in the assisted localization group (49.27±4.86) minutes was shorter than that in the traditional group (59.64±8.02) minutes (P 0.05). The excellent and good rate of Harris score in the assisted localization group was 89%. (4) No necrosis of femoral head occurred during the follow-up, and the rate of late necrosis should be followed up. (5) Our findings suggest that Kirschner wire positioning device can assist in quantitative positioning and guide the placement of cannulated screw in the internal fixation of femoral neck fracture. It can effectively improve the positioning efficiency, reduce the number of fluoroscopy, avoid repeatedly adjusting the penetration to damage femoral neck bone, and promote the recovery of patients.

Novel rotatable tabletop for total-body irradiation using a linac-based VMAT technique.

BACKGROUND: Volumetric Modulated Arc Therapy (VMAT) techniques have recently been implemented in clinical practice for total-body irradiation (TBI). To date, most techniques still use special couches, translational tables, or other self-made immobilization devices for dose delivery. Aim of the present study was to report the first results of a newly developed rotatable tabletop designed for VMAT-TBI. METHODS: The VMAT-TBI technique theoretically allows the use of any standard positioning device at the linear accelerator. Nevertheless, the main problem is that patients taller than 120 cm cannot be treated in one position due to the limited cranial-caudal couch shift capacities of the linac. Therefore, patients are usually turned from a head-first supine position (HFS) to a feet-first supine position (FFS) to overcome this limitation. The newly developed rotatable tabletop consists completely of carbon fiber, including the ball bearing within the base plate of the rotation unit. The patient can be turned 180° from a HFS to a FFS position within a few seconds, without the need of repositioning. RESULTS: The first 20 patients had a median age of 47 years, and received TBI before bone marrow transplantation for acute myeloid leukemia. Most patients (13/20) received a TBI dose of 4 Gy in 2 fractions, twice daily. The mean number of applied monitor units (MU) was 6476 MU using a multi-arcs and multi-isocenter VMAT-TBI technique. The tabletop has been successfully used in daily clinical practice and helped to keep the treatment times at an acceptable level. During the first treatment fraction, the mean overall treatment time (OTT) was 57 min. Since no additional image guidance was used in fraction 2 of the same day, the OTT was reduced to mean 38 min. CONCLUSIONS: The easy and reproducible rotation of the patient on the treatment couch using the rotatable tabletop, is time-efficient and overcomes the need of repositioning the patient after turning from a HFS to a FFS position during VMAT TBI. Furthermore, it prevents couch-gantry collisions, incorrect isocenter shifts and beam mix-up due to predicted absolute table coordinates, which are recorded to the R + V system with the corresponding beams.

The Normal 3D Gleno-humeral Relationship and Anatomy of the Glenoid Planes.

Knowledge of the normal and pathological three-dimensional (3D) gleno-humeral relationship is imperative when planning and performing a total shoulder arthroplasty. Currently, two-dimensional (2D) parameters are used to describe this anatomy and despite the fact that these 2D measurements have a wide distribution in the normal population, they are commonly accepted. This broad distribution can be explained on one hand by anatomical factors and on the other hand, by positional errors. A 3D CT-scan reconstruction and evaluation can overcome this shortcoming and can be used to determine more accurately the surgical planes on the normal and pathological shoulder joint. There is, however, no consensus on which references should be used when studying this 3D relationship. This thesis describes the normal 3D gleno-humeral relationship and the best glenoid plane to use in surgery, based on 3D CT-scan. Furthermore, a glenoid aiming device that can be of surgical help in the reconstruction of the normal glenoid anatomy was developed based on these measurements.

Intraspinal Delivery of Schwann Cells for Spinal Cord Injury.

Cell transplant-mediated tissue repair of the damaged spinal cord is being tested in several clinical trials. The current candidates are neural stem cells, stromal cells, and autologous Schwann cells (aSC). Due to their peripheral origin and limited penetration of astrocytic regions, aSC are transplanted intralesionally as compared to neural stem cells that are transplanted into intact spinal cord. Injections into either location can cause iatrogenic injury, and thus technical precision is important in the therapeutic risk-benefit equation. In this chapter, we discuss how we bridged from transplant studies in large animals to human application for two Phase 1 aSC transplant studies, one subacute and one chronic. Preclinical SC transplant studies conducted at the University of Miami in 2009-2012 in rodents, minipigs, and primates supported a successful Investigational New Drug (IND) submission for a Phase 1 trial in subacute complete spinal cord injury (SCI). Our studies optimized the safety and efficiency of intralesional cell delivery for subacute human SCI and led to the development of new simpler techniques for cell delivery into subjects with chronic SCI. Key parameters of delivery methodology include precision localization of the injury site, stereotaxic devices to control needle trajectory, method of entry into the spinal cord, spinal cord motion reduction, the volume and density of the cell suspension, rate of delivery, and control of shear stresses on cells.

Factors related with public open space use among adolescents: a study using GPS and accelerometers.

BACKGROUND: Low physical activity levels and high levels of sedentary time among adolescents call for population wide interventions. Public open spaces can be important locations for adolescents' physical activity. This study aimed to describe the prevalence, frequency and context of public open space visitation and to gain insight into the individual, social and physical environmental factors associated with public open space use among 12- to 16-year-old Flemish (Belgian) adolescents. METHODS: Global positioning system devices, accelerometers and one-on-one interviews were used to measure location-specific activity levels, time spent at, reasons for using and accompaniment at public open spaces among 173 adolescents. Multilevel hurdle and gamma models were used to estimate the associations between the independent variables (age, gender, ethnicity, education, sport club membership and accompaniment) and the amount of time, sedentary time, light-, moderate- to vigorous- and vigorous-intensity physical activity at public open spaces. RESULTS: Three out of four participants had visited a public open space (for recreational purposes) and participants were most often accompanied by friends/classmates. Mainly public transportation stops/stations were used, and subsequently the most reported reason for public open space use was "to wait for something or someone". Furthermore, boys, younger adolescents, non-western-European adolescents and lower educated adolescents were more likely to use public open spaces. Additionally, boys and younger adolescents were more likely to accumulate physical activity at public open spaces. The only social environmental variable associated with time spent at public open spaces was accompaniment by siblings: adolescents spent more time at public open spaces when accompanied by their siblings. CONCLUSIONS: Public open spaces may be effective areas to promote physical activity among groups at risk for physical inactivity (i.e. low educated and non-western-European adolescents). Additionally, girls and older adolescents were less likely to visit and be physically active at public open spaces. Therefore, urban planners should consider adding attractive features, in order to encourage physical activity among girls and older adolescents at public open spaces. Furthermore, creating public open spaces that are attractive for youth of all ages could contribute to adolescents visiting public open spaces accompanied by siblings.

Design of CT-guided puncture positioning device / 医疗卫生装备

Objective To design a CT-guided puncture positioning device to shorten puncture time while increase the accuracy. Methods The device realized 3D positioning by the principle of plane geometry, which was composed of a positioner,a fixation mechanism and a direction guiding mechanism for puncture needle.The positioner and direction guiding mechanism were made of transparent plastic, and the fixation mechanism was made of elastic cloth. Results The device gained advantages over the traditional means in puncture time,times of needle insertion and times of CT scanning,and had the puncture success rate in one time being 90%. Conclusion The device behaves well in focal positioning and puncture needle guiding,and thus decreases the probability of failed puncture and the patient pains.

Treatment of laryngopharyngeal reflux using a sleep positioning device: A prospective cohort study.

OBJECTIVE: Laryngopharyngeal reflux (LPR) symptoms are often resistant to management and cause significant quality of life impairment to patients with this disease. This study assesses the utility of a sleep-positioning device (SPD) in treating LPR. DESIGN: Single center prospective cohort study. SETTING: Tertiary medical center PARTICIPANTS: 27 adult patients with diagnosed laryngopharyngeal reflux. INTERVENTION: An SPD consisting of a two-component wedge-shaped base pillow and a lateral positioning body pillow (Medcline, Amenity Health Inc.) was given to patients with a diagnosis of LPR. Subjects slept using the device for at least 6h per night for 28 consecutive nights. MAIN OUTCOMES: Primary outcomes were Nocturnal Gastroesophageal Reflux Symptom Severity and Impact Questionnaire (N-GSSIQ) and the Reflux Symptoms Index (RSI) survey instrument. Each was collected at baseline, after 14, and after 28days of SPD use. RESULTS: 27 patients (19 female and 8 male; age 57.1±12.8, BMI 29.0±8.1) were recruited. At baseline mean N-GSSIQ was 50.1±22.4 and mean RSI of 29.6±7.7. Repeated measure analysis showed that subjects' total N-GSSIQ scores decreased by an average of 19.1 (p=0.0004) points by two weeks and 26.5 points by 4weeks (p<0.0001). RSI decreased an average of 5.3 points by 2weeks (p=0.0425) and an average of 14.0 points by 4weeks (p<0.0001). CONCLUSIONS: In patients with LPR, SPD treatment significantly improves self-reported symptoms of nocturnal reflux as well as symptoms specific to LPR. These results support the therapeutic efficacy of a SPD for patients with LPR.

A comparative research between traditional positioning device and a new type percutaneous kyphoplasty positioning device / 中国医学装备

Objective:To compare the accuracy and safety between percutaneous kyphoplasty (PKP) positioning device and traditional positioning device which posit entry point of pedicle of vertebral arch by using the C-arm X-ray.Methods: 117 patients with spinal centrum compression fractures were divided into positioning device group (57 cases) and Kirschner wire group (60 cases) depended on the entry point marked by the preoperative C arm X-ray irradiation. To compare the excellence rate, operation time and exposure times between PKP positioning device and traditional device.Results: The positioning times of the PKP positioning device group and Kirschner wire group were (2.3±0.9)min and (6.8±1.3)min, respectively. The exposure times of the two group were 1.6 times and 4.7 times, respectively. And both of the two differences were statistical significant (t=21.062,t=18.521;P0.05).Conclusion: There are series of advantages in developed PKP positioning device, such as portable, easy and simple control, higher accuracy and safety, less positioning time and exposure times of C arm X-ray.

Application of CT-guided self-made localization puncture device in radiofrequency ablation of liver tumors / 肿瘤研究与临床

Objective To evaluate the value of CT-guided self-made positioning puncture device in radiofrequency ablation of liver tumors. Methods A total of 78 tumor foci from 64 patients with primary hepatocellular carcinoma treated with radiofrequency ablation from January 2010 to November 2014 were analyzed. Among them, 13 tumor diameters were 3.5-5.0 cm and 65 < 3.5 cm. The location and puncture of tumor lesion were performed by CT-guided positioning device, and the effect of puncture and lesion was evaluated by using tumor precise radiotherapy planning system. Radiofrequency ablation of tumor lesion was performed by tumor radiofrequency treatment system. Results The puncture error of all tumors in the space was 1-4 mm, the average puncture error was 2.9 mm, the complete ablation rate of tumor lesions was 93.59%(73/78), and there was no serious complication in the course of treatment. After treatment, the alpha-fetoprotein and liver function were significantly improved, and the differences were statistically significant (both P<0.05). At 1 month after surgery, CT found that no tumor and ablation was enhanced, at 3 months after surgery, CT showed that the arterial phase of all the tumor lesions did not strengthen, all of them were low-density lesions, no ablation recurred. The recurrence rates of 1, 2, 3, and 4 years after treatment were 17.9 %, 29.9 %, 45.9 % and 55.0 %. Conclusion CT-guided radiofrequency ablation with self-made puncture device is effective in the diagnosis of primary liver cancer, ablation is complete and safe.

[Addition to the dorsal decubitus position for scapular based flap harvest: The Spider® limb positioning system]. / Amélioration de la technique de prélèvement des lambeaux périscapulaires grâce au système de positionnement de membre Spider®.

Subscapular vascular system based flaps provide excellent solutions for the coverage of a large variety of soft tissue defects. Dorsal decubitus position allows two teams of surgeons to work simultaneously and to harvest the flap in both an effective and safer way. Previously described for orthopaedic surgery, the Spider® limb positioning system offers a precious addition to the technique, giving a simple mean to keep the arm in the desired position while harvesting the flap. The need for an assistant to hold the upper limb is no longer required, enabling him to help in a more effective and time sparing way during surgery.

Stress radiography for clinical evaluation of anterior shoulder instability.

BACKGROUND: The purpose of this study was to examine the validity of stress radiography using the Telos GA-IIE as a clinical methodology to evaluate shoulder instability. METHODS: On 36 anterior shoulder dislocators and 23 uninjured volunteers, 4 types of stress radiographs were captured while applying 15 daN of force anteriorly (AER0 and AER60) and posteriorly (PER0 and PER60) at 2 different positions: (1) 90° of abduction combined with 0° external rotation and (2) 90° of abduction combined with 60° external rotation. The results of the anterior drawer test and of the same test under anesthesia were correlated. RESULTS: AER0 and AER60 from the affected shoulder revealed significantly larger displacement than on the normal side (P < .05), and all 4 radiographs from the affected joints demonstrated significantly larger displacement (P < .05) than in the volunteers. Among the 4 types of radiographs, AER0 and AER60 showed significantly higher displacement in the patients (P < .001), whereas there were no differences in the volunteers (P = .167). The results of the anterior drawer test positively correlated to AER60 (Pearson correlation coefficient [PCC] = 0.453; P = .005) and AER0 (PCC = 0.529; P = .001), and those of examination under anesthesia weakly correlated to AER60 (PCC = 0.287; P = .264) but highly correlated to AER0 (PCC = 0.695; P = .002). CONCLUSION: Stress radiographs on the affected shoulder frequently correlated with physical examinations, and the displacement of >3 mm on AER0 suggests anterior instability.

A patient immobilization device for prone breast radiotherapy: Dosimetric effects and inclusion in the treatment planning system.

PURPOSE: To assess the dosimetric impact of a patient positioning device for prone breast radiotherapy and assess the accuracy of a treatment planning system (TPS) in predicting this impact. METHODS: Beam attenuation and build-up dose perturbations, quantified by ionization chamber and radiochromic film dosimetry, were evaluated for 3 components of the patient positioning device: the carbon fiber baseplate, the support cushions and the support wedge for the contralateral breast. Dose calculations were performed using the XVMC dose engine implemented in the Monaco TPS. All components were included during planning CT acquisition. RESULTS: Beam attenuation amounted to 7.57% (6MV) and 5.33% (15MV) for beams obliquely intersecting the couchtop-baseplate combination. Beams traversing large sections of the support wedge were attenuated by 12.28% (6MV) and 9.37% (15MV). For the support cushion foam, beam attenuation remained limited to 0.11% (6MV) and 0.08% (15MV) per centimeter thickness. A substantial loss of dose build-up was detected when irradiating through any of the investigated components. TPS dose calculations accurately predicted beam attenuation by the baseplate and support wedge. A manual density overwrite was needed to model attenuation by the support cushion foam. TPS dose calculations in build-up regions differed considerably from measurements for both open beams and beams traversing the device components. CONCLUSIONS: Irradiating through the components of the positioning device resulted in a considerable degradation of skin sparing. Inclusion of the device components in the treatment planning CT allowed to accurately model the most important attenuation effect, but failed to accurately predict build-up doses.

CAD/CAM splint based on soft tissue 3D simulation for treatment of facial asymmetry.

BACKGROUND: Most cases of facial asymmetry involve yaw deformity, and determination of the yaw correction level is very difficult. METHODS: We use three-dimensional soft tissue simulation to determine the yaw correction level. This three-dimensional simulation is based on the addition of cephalometric prediction to gradual yaw correction. Optimal yaw correction is determined visually, and an intermediate splint is fabricated with computer-aided design and computer-aided manufacturing. Application of positioning devices and the performance of horseshoe osteotomy are advisable. RESULTS: With this procedure, accurate repositioning of jaws was confirmed and patients obtained fairly good facial contour. CONCLUSIONS: This procedure is a promising method for a widespread, predictable treatment of facial asymmetry.

Application of a self-made positioning device in laryngeal CT-MRI image fusion / 中华放射肿瘤学杂志

Objective To investigate the application of a self-made positioning device in CT-MRI image fusion in patients with laryngeal tumor,as well as the precision of image fusion and the changes in target volume delineation after fusion.Methods A total of 10 patients with laryngeal cancer were enrolled,and a self-made positioning device was used to collect CT and MRI images in a fixed position.These images were fused by mutual information combined with manual fusion.The precision of image fusion was assessed by the positional deviation of internal and external markers and degree of gross tumor volume (GTV) overlap (PCT-MRI) between CT and MRI images.GTV was contoured based on CT images (VCr),MRI images (VMRI),and fused images (VCT+MRI).The overlapped volume of VCT and VMRI(VCT-MRI) Was calculated,and the target volume was analyzed and compared.Results The positional deviations of three external markers in the three directions were 0.996±0.222 mm,1.146±0.291 mm,and 1.368±0.298 mm (P=0.000),respectively,while those of the internal markers were 0.476±0.151 mm,0.561±0.083 mm,and 0.724± 0.125 mm (P=0.000),respectively.VCT,VMRI,VCT+MRI,and VCT-MRI were 26.355±7.876 cm3,33.556± 7.407 cm3,40.036±7.627 cm3,19.875±8.588 cm3(P=0.000),respectively.PCT-MRI was 73.7％±9.8％.Conclusions The self-made positioning device can improve the consistency of position during the collection of CT and MRI images,and fused CT-MRI images can provide more information and improve the precision of target volume delineation.

CAD/CAM splint based on soft tissue 3D simulation for treatment of facial asymmetry / 대한악안면성형재건외과학회지

BACKGROUND: Most cases of facial asymmetry involve yaw deformity, and determination of the yaw correction level is very difficult. METHODS: We use three-dimensional soft tissue simulation to determine the yaw correction level. This three-dimensional simulation is based on the addition of cephalometric prediction to gradual yaw correction. Optimal yaw correction is determined visually, and an intermediate splint is fabricated with computer-aided design and computer-aided manufacturing. Application of positioning devices and the performance of horseshoe osteotomy are advisable. RESULTS: With this procedure, accurate repositioning of jaws was confirmed and patients obtained fairly good facial contour. CONCLUSIONS: This procedure is a promising method for a widespread, predictable treatment of facial asymmetry.