The Influence of the Insertion Angle on Middle and Lower Face Tissue-Mechanics When Treating the Nasolabial Folds with Facial Suspension Threads—An Experimental Split-Face Cadaveric Study

2020 ◽  
Vol 36 (03) ◽  
pp. 268-275
Author(s):  
Martin Braun ◽  
Konstantin Frank ◽  
David L. Freytag ◽  
Robert H. Gotkin ◽  
Nirusha Lachman ◽  
...  

AbstractA novel treatment approach to address the nasolabial fold is the insertion facial suspension threads. However, there is a paucity of data available to guide insertion techniques and material selection. Three female and two male cephalic specimens of Caucasian ethnicity (73.6 ± 6.5 years; 21.41 ± 2.2 kg/m2) were included into this experimental split-face study. One facial side was treated with polycaprolactone (PCL) thread: 180 mm, bidirectional, 18G 100 mm cannula, 20 degrees trajectory, preauricular approach whereas the contralateral side was treated with polydioxanone (PDO) thread: 100 mm, bidirectional, 19G, 60 mm cannula, 50 degrees trajectory, infraorbital approach. Three-dimensional imaging outcome measures included vertical and horizontal skin displacement and volume changes at the nasolabial sulcus, at the labiomandibular sulcus, and along the jawline. Comparing PCL 180 mm 20 degrees to PDO 100 mm 50 degrees: vertical lifting effect 1.42 ± 2.63 mm versus 1.24 ± 1.88 mm (p = 0.906); horizontal lifting effect 3.42 ± 1.44 mm versus –2.02 ± 1.84 mm (p = 0.001); nasolabial volume change –0.80 ± 0.65 mL versus –0.52 ± 0.17 mL (p = 0.367); labiomandibular volume change –0.45 ± 0.42 mL versus –0.16 ± 0.16 mL (p = 0.191); jawline volume change 0.02 ± 0.43 mL versus –0.01 ± 0.21 mL (p = 0.892). The study provides objective evidence for the short-term effectiveness of facial suspension threads in treating the nasolabial folds. The results point toward a better aesthetic outcome when utilizing long facial suspension threads that can effect full-face changes as compared with short facial suspension threads.

2019 ◽  
Vol 84 ◽  
pp. 16-33 ◽  
Author(s):  
Lei Zhang ◽  
Guojing Yang ◽  
Blake N. Johnson ◽  
Xiaofeng Jia

2007 ◽  
Vol 60 (suppl_2) ◽  
pp. ONS-129-ONS-139 ◽  
Author(s):  
Daisuke Togawa ◽  
Mark M. Kayanja ◽  
Mary K. Reinhardt ◽  
Moshe Shoham ◽  
Alin Balter ◽  
...  

Abstract Objective: To evaluate the accuracy of a novel bone-mounted miniature robotic system for percutaneous placement of pedicle and translaminar facet screws. Methods: Thirty-five spinal levels in 10 cadavers were instrumented. Each cadaver's entire torso was scanned before the procedure. Surgeons planned optimal entry points and trajectories for screws on reconstructed three-dimensional virtual x-rays of each vertebra. Either a clamp or a minimally invasive external frame was attached to the bony anatomy. Anteroposterior and lateral fluoroscopic images using targeting devices were obtained and automatically registered with the virtual x-rays of each vertebra generated from the computed tomographic scan obtained before the procedure. A miniature robot was mounted onto the clamp and external frame and the system controlled the robot's motions to align the cannulated drill guide along the planned trajectory. A drill bit was introduced through the cannulated guide and a hole was drilled through the cortex. Then, K-wires were introduced and advanced through the same cannulated guide and left inside the cadaver. The cadavers were scanned with computed tomography after the procedure and the system's accuracy was evaluated in three planes, comparing K-wire positions with the preoperative plan. A total of fifty-five procedures were evaluated. Results: Twenty-nine of 32 K-wires and all four screws were placed with less than 1.5 mm of deviation; average deviation was 0.87 ± 0.63 mm (range, 0-1.7 mm) from the preoperative plan in this group. Sixteen of 19 K-wires were placed with less than 1.5 mm of deviation. There was one broken and one bent K-wire. Another K-wire was misplaced because of collision with the previously placed wire on the contralateral side of the same vertebra because of a mistake in planning, resulting in a 6.5-mm deviation. When this case was excluded, average deviation was 0.82 ± 0.65 mm (range, 0-1.5 mm). Conclusion: These results verify the system's accuracy and support its use for minimally invasive spine surgery in selected patients.


2012 ◽  
Vol 32 (4) ◽  
pp. 488-494 ◽  
Author(s):  
Armando A. Davila ◽  
Donald W. Buck ◽  
David Chopp ◽  
Caitlin M. Connor ◽  
Scott Persing ◽  
...  

2020 ◽  
Author(s):  
Peyman Bakhshayesh ◽  
Ugwunna Ihediwa ◽  
Sukha Sandher ◽  
Alexandros Vris ◽  
Nima Heidari ◽  
...  

Abstract Introduction: Rotational deformities following IM nailing of tibia has a reported incidence of as high as 20%. Common techniques to measure deformities following IM nailing of tibia are either based on clinical assessment, plain X-rays or CT-scan comparing the treated leg with the uninjured contralateral side. All these techniques are based on examiners manual calculation inherently subject to bias. Following our previous rigorous motion analysis and symmetry studies on hemi pelvises, femurs and orthopaedic implants, we aimed to introduce a novel fully digital technique to measure rotational deformities in the lower legs.Material and Methods: Following formal institutional approval from the Imperial College, CT images of 10 pairs of human lower legs were retrieved. Images were anonymized and uploaded to a research server. Three dimensional CT images of the lower legs were bilaterally reconstructed. The mirrored images of the left side were merged with the right side proximally as stationary and distally as moving objects. Discrepancies in translation and rotation were automatically calculated.Results: Our study population had a mean age of 54 ± 20 years. There were six males and four females. We observed a greater variation in translation (mm) of Centre of Mass (COM) in sagittal plane (CI: -2.959--.292) which was also presented as rotational difference alongside the antero-posterior direction or Y axis (CI: .370-1.035). In other word the right lower legs in our study were more likely to be in varus compared to the left side. However, there were no statistically significant differences in coronal or axial planes.Conclusion: Using our proposed fully digital technique we found that lower legs of the human adults were symmetrical in axial and coronal plane. We found sagittal plane differences which need further addressing in future using bigger sample size. Our novel recommended technique is fully digital and commercially available. This new technique can be useful in clinical practice addressing rotational deformities following orthopaedic surgical intervention. This new technique can substitute the previously introduced techniques.


Author(s):  
Yuju Jeon ◽  
Jonghak Kim ◽  
Haeseong Jang ◽  
Jeongin Lee ◽  
Min Gyu Kim ◽  
...  

Reversible lithium metal plating and stripping is required for durable operation of lithium metal batteries. Three-dimensional architecture has been employed for accommodating volume change of lithium metal during repeated plating...


2019 ◽  
Vol 7 (11) ◽  
pp. 6090-6098 ◽  
Author(s):  
Yangyang Feng ◽  
Chaofan Zhang ◽  
Bing Li ◽  
Shizhao Xiong ◽  
Jiangxuan Song

We report a novel concept for a stable Li metal anode via the synergistic effect of a three-dimensional skeleton and stable artificial SEI.


2020 ◽  
Vol 24 (12) ◽  
pp. 4363-4372
Author(s):  
Yun-Fang Chen ◽  
Frank Baan ◽  
Robin Bruggink ◽  
Ewald Bronkhorst ◽  
Yu-Fang Liao ◽  
...  

Abstract Objectives This study aimed to investigate the three-dimensional (3D) mandibular asymmetry in craniofacial microsomia (CFM) and its association with the Pruzansky–Kaban classification system. Materials and methods Cone-beam computed tomography images of 48 adult CFM cases were collected. The asymmetry of the mandibular body and ramus was analyzed with 3D landmarks. The mirrored mandibular model was registered on the original model, yielding a color-coded distance map and an average distance (i.e., asymmetry score) to quantify the overall mandibular asymmetry. Results The lengths of the mandibular body and ramus were significantly shorter on the affected than the contralateral side (p < 0.001). The ANB (p = 0.009), body and ramal lengths (both p < 0.001), and body and ramal length asymmetry (both p < 0.05) were significantly different between mild (types I/IIA) and severe (types IIB/III) cases. The mandibular asymmetry score correlated with mandibular body length asymmetry (r = 0.296, p = 0.046). CFM mandibles showed high variability in shape asymmetry. Conclusions CFM patients showed distinct body and ramal length asymmetries. In severe cases, mandibles were smaller, more retruded, and more asymmetric in length. The mandibular shape asymmetry was highly variable regardless of the Pruzansky–Kaban types, being a determinant in the extent of overall mandibular asymmetry. Clinical relevance The 3D morphologic analysis provides better insights into real mandibular asymmetry. Although the Pruzansky–Kaban classification was applied, high individual variability of the mandibular morphology still existed within the types. Therefore, individualized analyses and treatment plans for CFM patients are highly recommended.


2014 ◽  
Vol 592-594 ◽  
pp. 1789-1793
Author(s):  
Amarjeet Singh ◽  
Vinod Kumar Mittal ◽  
Surjit Angra

Crankshaft is one of the most important components of an IC engine. Crankshaft should be checked carefully to ensure that its design is fully optimized. The main objective of this paper is to perform the static analysis on four cylinder engine crankshaft to find out its static strength and the maximum stress zone and analyzing the different methods for the optimization of crankshaft in terms of weight, stress and cost reduction. A three dimensional model of four cylinder engine crankshaft is prepared corresponding to actual conditions in Catia V5 software, static analysis is performed using Ansys under extreme operating conditions and the improvement methods for the optimum design are analyzed in terms of geometric improvement, appropriate material selection and methods used for manufacturing of crankshaft.


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