Continuity Defects Research Articles

Increasing the crack resistance when pressing pipes made of 08Kh13N4M1F steel

The main factor determining the possible appearance of continuity defects in hotpressed pipes is the physical nature of the material subjected to deformation, namely, its plasticity. Alloying of a metal contributes to a decrease in its plasticity and an increase in the resistance to plastic deformation, which, on the one hand, increases the stress level during hot deformation, and, on the other hand, reduces the threshold stress value corresponding to the onset of metal fracture. The introduction of computer simulation tools, in particular software products based on the finite element method, made it possible to perform an analytical study of the features of the stress-strain state of the metal during hot pressing of steel pipes. Particular attention in the modeling is paid to the deformation conditions of the surface layers of the metal, since one of the characteristic surface defects of hot-pressed pipes is cracks and ruptures. The dependences of the stress-strain state on the technological parameters of the pressing process are revealed, namely, the nature of the change in the stress-strain state of the surface layers of the pressed shell along the deformation zone length, the effect of temperature, elongation coefficient and friction coefficient on the change in the stress-strain state are determined, the degree of the plasticity resource use by the Kolmogorov failure criterion is assessed. On the basis of the results obtained, a set of theoretical and experimental studies was carried out to investigate the mechanisms of the formation of surface defects in hot-pressed pipes, technological parameters and technological tool parameters that contribute to the elimination of surface defects were determined.

Efficacy of locking miniplate in the treatment of mandibular fractures without intermaxillary fixation

Background: The introduction of locking plate/screw miniplate and reconstruction plating systems for the treatment of mandibular fractures and continuity defects has offered advantages over other plating systems. The present study was conducted to assess the efficacy of locking miniplate in the treatment of mandibular fractures without intermaxillary fixation. Materials & Methods: 56 patients with undisplaced or minimally displaced mandibular fractures of both genders were treated by open reduction and internal fixation using the 2.0 mm locking plates. Parameters such as cause of injury, site of fracture, complications etc. was recorded. Results: Out of 56 patients, males were 30 and females were 26. Causes of injury was RTA in 34, sports injury in 10, fall in 8 and miscellaneous in 4 cases. The site was right body in 12, left body in 15, right angle in 10, left angle in 8 and parasymphysis in 11 cases. Common complications was non- union seen in 2, infection in 5 and delayed union in 1 case. Conclusion: The locking miniplate system was found to be effective in management of mandibular fractures.

RESTORATION PROCESS OF THE OUTER RETINAL LAYERS AFTER SURGICAL MACULAR HOLE CLOSURE.

To investigate the interrelationship among the outer retinal layers after macular hole surgery and elucidate the restoration process. This retrospective observational study included 50 eyes of 47 consecutive patients with closed macular holes in the first vitrectomy. Optical coherence tomography was obtained before surgery; at 1, 3, and 6 months postsurgery; and at the last visit. The complete continuous layer rate and mean defect length were evaluated for the outer nuclear layer (ONL), external limiting membrane (ELM), and ellipsoid zone (EZ). At all postoperative visits, the complete continuous layer rate was in the descending order of ELM, ONL, and EZ and the mean defect length was in the ascending order of ELM, ONL, and EZ. External limiting membrane was necessary for ONL restoration. External limiting membrane and ONL were necessary for EZ restoration. Hyperreflective protrusions were observed from the area lacking ELM into the subretinal space after surgery. Ellipsoid zone was not formed in coexistence with the hyperreflective protrusions. Intermediate reflective protrusions appeared under the ONL plus ELM after surgery and were eventually replaced by EZ. Restoration of the outer retinal layers after surgical macular hole closure occurs in the order of ELM, ONL, and EZ.

Development of high strength Mg/Al bimetal by a novel ultrasonic vibration aided compound casting process

Ultrasonic vibration was proposed to enhance interface bonding of Mg/Al bimetal prepared by a novel lost foam compound casting (LFCC) to obtain high strength Mg/Al bimetal. The results showed that the interface of the Mg/Al bimetal without ultrasonic vibration was mainly composed of layer I (Al3Mg2 + Mg2Si), layer II (Al12Mg17 + Mg2Si), and layer III (Al12Mg17 + δ-Mg eutectic). Under the ultrasonic vibration, the Mg2Si and Al12Mg17 phases and the Al12Mg17 + δ-Mg eutectic at the interface were remarkably refined. After the ultrasonic vibration was applied, the Mg2Si phase was uniformly dispersed in the whole interface, and the continuous oxidation inclusion defect was eliminated. As a result, the microhardness of the entire interface became more uniform, and the shear strength of the Mg/Al bimetal significantly increased by 86.5 %, reaching 69 MPa, compared to the bimetal without ultrasonic vibration. The fracture surface of the Mg/Al bimetal without ultrasonic vibration exhibited an apparent brittle fracture morphology. Under the assist of the ultrasonic vibration, the shear strength of the bimetal was improved mainly due to the refinement of the interfacial microstructure, and the fracture surface of the Mg/Al bimetal generated a partial plastic deformation in the interface layer.

TO THE RECOGNITION OF STRESS-CORROSION CRACKS IN METAL BASED ON THE SIGNAL OF EDDY CURRENT TRANSDUCERS

This paper shows the investigation of some parameters of the applied eddy current transducers (ECT) signals over a group of stress-corrosion cracks in the metal. According to the research, the waveform of the superimposed ECT signal significantly changes with a change in the interval between defects in a group of cracks: with an increase in the gap between defects, local maxima appear in the absolute ECT signal, and the differential ECT signal shape takes on a noise-like character. In order to analyze the transformation of the signal’s shape of overhead ECT over a group of cracks, this paper proposes mathematical models based on which informative parameters (ECT signal amplitude and ECT signal half-width) were obtained. The mathematical models make recognition of groups of stress-corrosion cracks in the metal possible, even in the absence of spatial resolution of continuity defects. The paper considers an algorithm for recognizing a group of stress-corrosion cracks based on these informative parameters of the signal of the absolute superimposed ECT.

Patient-Specific Bioimplants and Reconstruction Plates for Mandibular Defects: Production Workflow and In Vivo Large Animal Model Study.

A major challenge with extensive craniomaxillofacial bone reconstruction is the limited donor-site availability to reconstruct defects predictably and accurately according to the anatomical shape of the patient. Here, patient-specific composite bioimplants, consisting of cross-linked poly(trimethylene carbonate) (PTMC) networks and β-tricalcium phosphate (β-TCP), are tested in vivo in twelve Göttingen minipigs in a large mandibular continuity defect model. The 25mm defects are supported by patient-specific titanium reconstruction plates and receive either osteoconductive composite bioimplants (PTMC+TCP), neat polymer network bioimplants (PTMC), autologous bone segments (positive control), or are left empty (negative control). Postoperatively, defects treated with bioimplants show evident ossification at 24 weeks. Histopathologic evaluation reveals that neat PTMC bioimplant surfaces are largely covered with fibrous tissue, while in the PTMC+TCP bioimplants, bone attached directly to the implant surface shows good osteoconduction and histological signs of osteoinductivity. However, PTMC+TCP bioimplants are associated with high incidence of necrosis and infection, possibly due to rapid resorption and/or particle size of the used β-TCP. The study highlights the importance of testing bone regeneration implants in a clinically relevant large animal model and at the in situ reconstruction site, since results on small animal models and studies in nonloadbearing areas do not translate directly.

Hydrodynamic effect of technological lubrication and friction modes formation at sheet rolling

One of the main engineering industries is the processing of metals by pressure. Its purpose is the formation of products from metal blanks of simple forms. An important role in this case belongs to the technology of sheet rolling. The solution of issues related to the choice of optimal modes of sheet rolling is relevant for specialists in the field under consideration. The process of rolling metal products is special, since the contact stresses can exceed the deformation resistance of rolled metal by several times. The tasks of predicting the quality of products, taking into account the prevention of sheet metal continuity defects, as well as the study of technological operations reliability of rolling process are associated with the solution of industrial and scientific problems in this area. Domestic and foreign researchers have noted a significant influence of external friction in the deformation center on the technological parameters of rolling process and quality of the resulting metal products. It is known that rolling is impossible without external friction between metal and roll. The reduction of friction provides an opportunity to increase the economic indicators of sheet rolling, and the rolling production technology itself has significant opportunities for further improvement. Technology of sheet rolling in the conditions of hydrodynamic friction mode allows modeling of friction conditions in the deformation zone. Taking into account the hydrodynamic effect of lubrication allows us to assess the influence of technological factors on the conditions of contact friction during metal pressure treatment and to control the rolling process. Regularities of the flow of liquid Newtonian lubricant are investigated, taking into account features of the deformation zone geometry during sheet rolling. Pumping capacity of the lubricating wedge during rolling is determined, which allows us to explain the regularities of lubrication influence on friction conditions. As an example, the results of calculation of the lubricant pressure depending on the rolling speed are presented. The rolling speeds that provide a liquid friction mode are given. The obtained relations allow us to estimate the influence of contact friction on technological parameters of sheet rolling and can be used in technological calculations of this process

CONSISTENT CONTINUOUS DEFECT THEORY

CONSISTENT CONTINUOUS DEFECT THEORY

Design Criteria for Patient-specific Mandibular Continuity Defect Reconstructed Implant with Lightweight Structure using Weighted Topology Optimization and Validated with Biomechanical Fatigue Testing.

This study developed design criterion for patient-specific reconstructed implants with appearance consideration and structural optimization of various mandibular continuity defects. The different mandible continuity defects include C (from left to right canines), B (from 1st premolar to 3rd molar), and A (from 3rd molar to ramus) segments defined based on the mandible image. The finite element (FE) analysis and weighted topology optimization methods were combined to design internal support beam structures within different reconstructed implants with corresponding occlusal conditions. Five continuity mandibular defects (single B/C/A+B and combination of B+C and B+C+B segments) were restored using additive manufacturing (AM) reconstructed implant and bone plate to confirm reasonable design criterion through biomechanical fatigue testing. The worst mandible strength was filtered based on the material mechanics and results from segmental bone length, thickness, and height statistics from the established database containing mandible images of 105 patients. The weighted optimization analysis results indicated that the sizes and positions of internal supporting beams within the reconstructed C, B, and A+B implants can be defined parametrically through corresponding segmental bone length, width, and height. The FE analysis found that the weight variation percentage between the parametric designed implants and original core solid implants in the C, B, and A+B was reduced by 54.3%, 63.7%, and 69.7%, respectively. The maximum stress values of the reconstructed implant and the remaining bone were not obviously reduced but the stress values were far lower than the material ultimate strength. The biomechanical fatigue testing indicated that all cases using the AM reconstructed implant could pass the 250,000 dynamic load. However, condyle head, bone plate fracture, and bone screw loosening could be found in cases using bone plates. This study developed a design criterion for patient-specific reconstructed implants for various mandibular continuity defects applicable for AM to further clinical use.

Structural Disorder in Layered Hybrid Halide Perovskites: Types of Stacking Faults, Influence on Optical Properties and Their Suppression by Crystallization Engineering.

Layered hybrid halide perovskites (LHHPs) are an emerging type of semiconductor with a set of unique optoelectronic properties. However, the solution processing of high-quality LHHPs films with desired optical properties and phase composition is a challenging task, possibly due to the structural disorder in the LHHP phase. Nevertheless, there is still a lack of experimental evidence and understanding of the nature of the structural disorder in LHHPs and its influence on the optical properties of the material. In the current work, using 2D perovskites (C4H9NH3)2(CH3NH3)n−1PbnI3n+1 (further BA2MAn−1PbnI3n+1) with n = 1–4 as a model system, we demonstrate that deviations in LHHPs optical properties and X-ray diffraction occur due to the presence of continuous defects—Stacking Faults (SFs). Upon analyzing the experimental data and modeled XRD patterns of a possible set of stacking faults (SFs) in the BA2MAPb2I7 phase, we uncover the most plausible type of SFs, featured by the thickness variation within one perovskite slab. We also demonstrate the successful suppression of SFs formation by simple addition of BAI excess into BA2MAn−1PbnI3n+1 solutions.

Dislocation Defect Layer-Induced Magnetic Bi-states Phenomenon in Epitaxial La0.7Sr0.3MnO3(111) Thin Films.

La0.7Sr0.3MnO3 (LSMO) is one of the most fascinating strongly correlated oxides in which the spin polarization and magnetic property are sensitive to strain, especially in the (111)-oriented LSMO. In the paper, epitaxial LSMO(111) thin films with different thicknesses were prepared, and they showed continuous dislocation defect arrays with thickness greater than 45 nm. Then, the thick LSMO(111) films were divided into a double-layer structure with two slightly different oriented cells. The LSMO(111) films present a stronger lattice-spin coupling, thus the double-layer structure triggers an obvious magnetic heterogeneity phenomenon (magnetic bi-states) by the way of creating a double-mode ferromagnetic resonance (FMR) spectrum. Therefore, the nanostructures, especially the ordered structure defects, may trigger enriched physical phenomena and offer new forms of spin coupling and device functionality in strain-sensitive strongly correlated oxide systems.

Lorentzian dynamics and factorization beyond rationality

We investigate the emergence of topological defect lines in the conformal Regge limit of two-dimensional conformal field theory. We explain how a local operator can be factorized into a holomorphic and an anti-holomorphic defect operator connected through a topological defect line, and discuss implications on analyticity and Lorentzian dynamics including aspects of chaos. We derive a formula relating the infinite boost limit, which holographically encodes the “opacity” of bulk scattering, to the action of topological defect lines on local operators. Leveraging the unitary bound on the opacity and the positivity of fusion coefficients, we show that the spectral radii of a large class of topological defect lines are given by their loop expectation values. Factorization also gives a formula relating the local and defect operator algebras and fusion categorical data. We then review factorization in rational conformal field theory from a defect perspective, and examine irrational theories. On the orbifold branch of the c = 1 free boson theory, we find a unified description for the topological defect lines through which the twist fields are factorized; at irrational points, the twist fields factorize through “non-compact” topological defect lines which exhibit continuous defect operator spectra. Along the way, we initiate the development of a formalism to characterize non-compact topological defect lines.

Defects in conformal crystals: Discrete versus continuous disclination models

We study the relationship between topological defect formation and ground-state 2D packings in a model of repulsions in external confining potentials. Specifically we consider screened 2D Coulombic repulsions, which conveniently parameterizes the effects of interaction range, but also serves as simple physical model of confined, parallel arrays of polyelectrolyte filaments or vortices in type II superconductors. The countervailing tendencies of repulsions and confinement to, respectively, spread and concentrate particle density leads to an energetic preference for nonuniform densities in the clusters. Ground states in such systems have previously been modeled as conformal crystals, which are composed of locally equitriangular packings whose local areal densities exhibit long-range gradients. Here we assess two theoretical models that connect the preference for nonuniform density to the formation of disclination defects, one of which assumes a continuum distributions of defects, while the second considers the quantized and localized nature of disclinations in hexagonal conformal crystals. Comparing both theoretical descriptions to numerical simulations of discrete particles clusters, we study the influence of interaction range and confining potential on the topological charge, number, and distribution of defects in ground states. We show that treating disclinations as continuously distributable well captures the number of topological defects in the ground state in the regime of long-range interactions, while as interactions become shorter range, it dramatically overpredicts the growth in total defect charge. Detailed analysis of the discretized defect theory suggests that that failure of the continuous defect theory in this limit can be attributed to the asymmetry in the preferred placement of positive vs negative disclinations in the conformal crystal ground states, as well as a strongly asymmetric dependence of self-energy of disclinations on sign of topological charge.

Spontaneous common bile duct perforation due to choledocolithiasis accompanied with pancreaticobiliary maljunction in an adult: a case report

BackgroundSpontaneous common bile duct (CBD) perforation is an extremely rare disease in adults. We report an adult case of CBD perforation due to choledocolithiasis accompanied with pancreaticobiliary maljunction, which is, to our knowledge, the first such case report based on a search using PubMed.Case presentationA 71-year-old woman with consciousness disorder was transported to the emergency department of another hospital. She was diagnosed as having severe peritonitis with septic shock and transferred to our hospital for emergency surgery. Enhanced computed tomography (CT) revealed supraduodenal CBD dilation similar to a diverticulum and a defect of bile duct wall continuity. Furthermore, CT showed a long common channel of the pancreaticobiliary duct, so she was diagnosed as having spontaneous CBD perforation with pancreaticobiliary maljunction. Emergency surgery was performed that revealed a necrotic diverticulum-like change on the supraduodenal part, and a 2.5 × 1 cm perforation was found on the anterolateral wall of the CBD. Peritoneal lavage was performed, and CBD perforation was resolved with a T-tube. The patient suffered refractory intra-abdominal and retroperitoneal abscess formation and bleeding from the abdominal wall, which required a long period of postoperative management. The T-tube was removed on day 136, and the patient was transferred on day 153.ConclusionThe cause of CBD perforation is commonly considered to be increased intraductal pressure or weakness of the bile duct wall. In this case, pancreaticobiliary maljunction may have significantly influenced onset and the postoperative course. This case suggests that early surgical intervention and appropriate drainage are important to ensure survival.

Application of an Ultra-Compact Eddy-Current Transducer for Investigation of Defects in Welded Joints of High-Strength Steel

This article discusses the results of work on the creation of a flaw detection unit, which is focused on the study of high-strength steels. Welded joints of transformer tanks, which are made of steel grade 08G2B, were selected as the object of research. We chose this grade because of the ultra-low carbon content of this material. This opens up opportunities for the application of eddy current nondestructive testing methods. For practical measurements, a scanning device was designed and optimized. It includes a converter that uses the principles of eddy currents and includes three coils assembled on a ferrite core, grade 80NMZ. The device was tested on samples with model continuity defects (cracks and holes). Also, within the framework of the publication, modeling of corrosion defects in welded joints was carried out.

Primary Reconstruction of Mandibular Defects after Resection of Aggressive Pediatric Mandibular Tumors by Split Rib Bundle Bone Graft. A Retrospective Study

Background: A retrospective study was done to evaluate the success rate of immediate reconstruction by split rib bundle bone grafting after segmental resection of Aggressive Pediatric mandibular tumors. Materials and Patients: The present study enrolled sixty-one pediatric patients with aggressive mandibular tumors that had been treated during the period from January 2008 to December 2018. All patients were examined clinically and radiographically by Orthopantomograms, CTs and CBCTs. Radical segmental resection with resultant mandibular continuity defects were thus created followed by immediate reconstruction with non-vascularized Split Rib Bundle Bone Graft (SRBBG). Patients were then rehabilitated by osseointegrated implants with fixed or removable partial dentures. Success of reconstruction was assessed by the percentage of complications, interincisal opening and patient satisfaction. Assessment was performed at 1,3,6 and 12 months postoperatively. All patients were followed up for 4-7 years. Results: Successful reconstruction was accomplished in 55 patients (90.16 %). Successful dental rehabilitation was accomplished in 49 patients (89%). Three patients had complete failure due to severe postoperative infection. Another three cases had partial resorption of the graft due to moderate infection to whom re-augmentation by another rib graft had been performed. Conclusion: Pediatric aggressive mandibular tumors should be treated in an aggressive manner relative to its biologic behavior and immediate reconstruction is advocated. The Split Rib Bundle Bone Graft is an adequate alternative for mandibular reconstruction in the absence of microvascular surgery as it shows early revascularization thus permitting rehabilitation with successfully osseointegrated dental implants.

Pre-contoured reconstruction plate fabricated via three-dimensional printed bending support.

A mandibular continuity defect can be repaired using either a prosthetic device or autogenous bone. A titanium reconstruction plate can be used with a localized or vascularized flap over the defect of the mandible. Unfortunately, the plate may fail due to plate exposure, screw loosening, fracture, or infection, and will need to be removed. Plate exposure though the skin or mucosa is one of the main reasons for failure. In the present work, the authors introduced a lingually positioned reconstruction plate fabricated via three-dimensional printed bending support. This custom reconstruction plate can avoid plate re-exposure as well as reduce surgical errors and operation time.

Effect of Ta irradiation on microstructures and current carrying properties of YBa<sub>2</sub>Cu<sub>3</sub>O<sub>7–</sub><sub><italic>δ</italic></sub>

High-temperature superconducting coated conductors (HTS CCs), which are based on epitaxial growth and biaxial texture technology of REBCO thin films, show excellent physical properties including high transition temperature T c,on, high irreversible field H irr, as well as high critical current density J c. However, YBa2Cu3O7– δ (YBCO) has limited applications in a high magnetic field because of low critical current. Previous studies have shown that building smaller artificial pinning centers (APCs) is an effective way to increase the J c of HTS CCs. Compared with the traditional chemical doping route, the particle irradiation method will result in various types and sizes of defects with uniform distribution by controlling the type, energy and dose of particles and keeping the original chemical ratio of the material. 1.2 µm YBCO superconducting layer was deposited on the LaMnO3 substrate of the samples by metal organic deposition (MOD) method. YBCO thin films were irradiated with 1.9 GeV Ta ions at room temperature and vacuum conditions. The microstructure of irradiated samples was systematically observed using a field emission transmission electron microscope (FETEM). The result shows that Ta ions do produce continuous columnar defects with uniform distribution in the superconducting layer of the YBCO films, and the size of the defects is about 10 nm. The basic superconducting parameters, such as T c,on and J c, were measured using magnetic property measurement system (MPMS). The result shows the T c,on of the pristine sample was 91.3 K. When the irradiation fluence was small, the T c,on of the doped sample was basically unchanged. As the fluence reached 5.0×1010 ions/cm2, the T c,on decreased by 0.6 K. In addition, the superconducting antimagnetic phases did not change much until the fluence exceeded 1.0×108 ions/cm2. After the fluence exceeded 1.0×108 ions/cm2, the superconducting antimagnetic phases increased obviously. They increased with the decrease of temperature as well. The result shows that J c increased obviously with the increase of fluence for the samples. In normal situation, the current carrying properties of the samples irradiated in the low field should decrease compared with that before irradiation, but the J c of the samples increased in the low field because of the increase of superconducting antimagnetic phases in the samples after irradiation. At 30 K and 1 T, the J c increased by 3 times of the original, and at 77 K, the J c also improved by 2.7 times in the same field. To analyze the pinning state in this process, the exponential relationship model of J c∝ H – β was used to fit the data of the samples at 30 K and 77 K. The result shows that the doped samples with 5.0×1010 ions/cm2 had the higher value of H * and β , which suggests the generation of new effective pinning centers due to the Ta ion implantation. The normalized pinning force f p = F p/ F p,max of samples irradiated with different fluence was analyzed as a function of the magnetic field h = H / H max by using Higuchi model. The fitting result shows that Ta ion irradiation does affect the pinning behavior of doped YBCO films. Further study is needed to find out why Ta ions have such effects on the YBCO films.

Implementation of Pavement Defect Detection System on Edge Computing Platform

Road surfaces in Taiwan, as well as other developed countries, often experience structural failures, such as patches, bumps, longitudinal and lateral cracking, and potholes, which cause discomfort and pose direct safety risks to motorists. To minimize damage to vehicles from pavement defects or provide the corresponding comfortable ride promotion strategy later, in this study, we developed a pavement defect detection system using a deep learning perception scheme for implementation on Xilinx Edge AI platforms. To increase the detection distance and accuracy of pavement defects, two cameras with different fields of view, at 70∘ and 30∘, respectively, were used to capture the front views of a car, and then the YOLOv3 (you only look once, version 3) model was employed to recognize the pavement defects, such as potholes, cracks, manhole covers, patches, and bumps. In addition, to promote continuous pavement defect recognition rate, a tracking-via-detection strategy was employed, which first detects pavement defects in each frame and then associates them to different frames using the Kalman filter method. Thus, the average detection accuracy of the pothole category could reach 71%, and the miss rate was about 29%. To confirm the effectiveness of the proposed detection strategy, experiments were conducted on an established Taiwan pavement defect image dataset (TPDID), which is the first dataset for Taiwan pavement defects. Moreover, different AI methods were used to detect the pavement defects for quantitative comparative analysis. Finally, a field-programmable gate-array-based edge computing platform was used as an embedded system to implement the proposed YOLOv3-based pavement defect detection system; the execution speed reached 27.8 FPS while maintaining the accuracy of the original system model.

Load-Bearing Capacity and Design Advantages of a Custom-Made, Thin Pure-Titanium Cranioplasty (CranioTop).

Adequate and stable coverage of cranial contour and continuity defects of any origin is a common challenge in neurosurgical clinics. This study presents the results of investigations concerning the mechanical load-bearing capacity and design advantages of custom-made implants made from a thin, pure-titanium sheet (CranioTop) (CLinstruments, Attendorn, Germany) for covering complex cranial defects. In 9 test series, the stability of three differently shaped and sized thin titanium sheet implants was tested using vertical, uniaxial compression with 3 different compression stamps, to investigate the behaviour of these implants in relation to punctiform as well as planar forces. All 9 model implants showed elastic behavior in the synchronously recorded force/displacement diagrams at an impression of up to 2 mm. The forces at 2 mm deformation were between 170.1 and 702.7 Newton. Cranioplasty using CranioTop is a stable procedure for covering skull defects, even those of large dimensions. An added advantage is the significant reduction in effort required to prepare the area of the bone margins compared to other current techniques of cranioplasty.