Biomechanical considerations of semi-anatomic glass fiber-reinforced (GFRC) composite implant for mandibular segmental defects: A technical note.

OBJECTIVES: The aim of this study was to investigate the selected biomechanical properties of semi-anatomic implant plate made of biostable glass fiber-reinforced composite (GFRC) for mandibular reconstruction. Two versions of GFRC plates were tested in vitro loading conditions of a mandible segmental defect model, for determining the level of mechanical stress at the location of fixation screws, and in the body of the plate. METHODS: GFRC of bidirectional S3-glass fiber weaves with dimethacrylate resin matrix were used to fabricate semi-anatomic reconstruction plates of two GFRC laminate thicknesses. Lateral surface of the plate followed the contour of the resected part of the bone, and the medial surface was concave allowing for placement of a microvascular bone flap in the next stages of the research. Plates were fixed with screws to a plastic model of the mandible with a large segmental defect in the premolar-molar region. The mandible-plate system was loaded from incisal and molar locations with loads of 10, 50, and 100 N and stress (microstrain, µÎµ) at the location of fixation screws and the body of the plate was measured by strain gauges. In total the test set-up had four areas for measuring the stress of the plate. RESULTS: No signs of fractures or buckling failures of the plates were found during loading. Strain values at the region of the fixation screws were higher with thick plate, whereas thin plates demonstrated higher strain at the body of the plate. Vertical displacement of the mandible-plate system was proportional to the loading force and was higher with incisal than molar loading locations but no difference was found between thin and thick plates. CONCLUSION: GFRC plates withstood the loading conditions up to 100 N even when loaded incisally. Thick plates concentrated the stress to the ramus mandibulae region of the fixation screws whereas the thin plates showed stress concentration in the angulus mandibulae region of the fixation and the plate itself. In general, thin plates caused a lower magnitude of stress to the fixation screw areas than thick plates, suggesting absorption of the loading energy to the body of the plate.

Patient-Specific 3D-Printed Osteotomy Guides and Titanium Plates for Distal Femoral Deformities in Dogs with Lateral Patellar Luxation.

The aim of this study was to describe the diagnosis and treatment of grade IV lateral patellar luxation (LPL) in two adult large breed dogs with complex femoral deformities using patient-specific three-dimensionally (3D) printed osteotomy guides and implants. Computed tomography (CT) scans were obtained for virtual surgical planning (VSP) using computer-aided design (CAD) software, which allowed for 3D reconstruction and manipulation of the femoral deformities, providing a preoperative view of the correction. Of the two patients, one was affected bilaterally and the other unilaterally, but both dogs were from the same litter. Therefore, the healthy femur of the unilaterally affected patient was used as the physiological reference for the virtual surgical correction. Three distal femoral trapezoid osteotomies (DF-TO) followed by reduction and internal fixation with plates were performed using patient-specific 3D-printed osteotomy guides and implants. This type of osteotomy permitted correction of procurvatum in all the femurs to increase knee extension, raise the dog's lumbar spine and correct the kyphosis. Preoperative, expected and postoperative femoral angles were compared to evaluate the efficacy of virtual surgical planning and the outcome of surgical correction. Radiographic follow-up, passive range of motion and functional recovery were recorded. There were no major complications requiring revision surgery. Significant clinical improvement was observed in both patients. This study suggests that the treatment used represents a viable surgical alternative to restore limb alignment in patients with complex femoral deformities.

Exploring Advanced Functionalities of Carbon Fiber-Graded PEEK Composites as Bone Fixation Plates Using Finite Element Analysis.

This study aims to address the challenges associated with conventional metallic bone fixation plates in biomechanical applications, such as stainless steel and titanium alloys, including stress shielding, allergic reactions, corrosion resistance, and interference with medical imaging. The use of materials with a low elastic modulus is regarded as an effective approach to overcome these problems. In this study, the impact of different types of chopped carbon fiber-reinforced polyether ether ketone (CCF/PEEK) functionally graded material (FGM) bone plates on stress shielding under static and instantaneous dynamic loading was explored using finite element analysis (FEA). The FGM bone plate models were established using ABAQUS and the user's subroutine USDFLD and VUSDFLD, and each model was established with an equivalent overall elastic modulus and distinctive distributions. The results revealed that all FGM bone plates exhibited lower stress shielding effects compared to metal bone plates. Particularly, the FGM plate with an elastic modulus gradually increased from the centre to both sides and provided maximum stress stimulation and the most uniform stress distribution within the fractured area. These findings offer crucial insights for designing implantable medical devices that possess enhanced mechanical adaptability.

An automatic reduction method of 3D bone fragments based on a novel section contour point descriptor.

Comminuted fractures are orthopedic traumas with greater surgical difficulty. In clinical treatment, a great challenge is precise reduction of multiple broken bone fragments; Another great challenge is personalized and precise internal fixation after reduction. For these two issues, we designed an automated method framework for precise reduction and internal fixation of comminuted fractures. First, the Gaussian mixture model (GMM) is used to distinguish section points and noise points in a broken bone model; Second, ellipse fitting is carried out to achieve section points matching and a descriptor is proposed to describe the section features; Then, the Convolution Auto-Encoder (CAE) and genetic algorithm are used to extract feature vectors; Finally, after broken bone models registration, internal fixed plate can be reconstructed. Three verification experiments for comminuted bone fracture show this method has high accuracy and good efficiency. It can provide support for minimally invasive treatment for comminuted fractures.

KNEE PERIPROSTHETIC FRACTURES IN THE ELDERLY: CURRENT CONCEPT.

Periprosthetic fractures around total knee arthroplasty in elderly represent an emerging cause of implant revision and their incidence seems destined to further increase in the upcoming years, considering the ever-increasing number of implanted prostheses. These are complex injuries with very high complication rates. It has been estimated that the incidence of femoral periprosthetic fractures after T.K.A. ranged between 0,3 to 2,5%, but increases up to 38% when considering revision T.K.A. Patient-related risk factors for T.K.A. periprosthetic fracture (T.K.A.P.F.) include osteoporosis, age, female sex, revision arthroplasty and peri-implant osteolysis. The grate debate concerns the choice of the most appropriate fixation device for T.K.A.P.F.: closed or open reduction with internal fixation with either locked plate or intramedullary nail is the most commonly used for treating these fractures. Success of these methods depends on the fracture pattern, the stability of implants, and the patient's bone quality which is often poor in elderly, thus resulting in high complication rates. Conversely, a revision of T.K.A. (R.T.K.A.) should be considered in case of prosthetic component instability, severe comminution or metaphyseal extension of the fracture (that precludes a good fixation), previous treatments failure and severe malalignment of T.K.A. Instead megaprosthesis and allograft-prosthesis composite are necessary in case of sever bone loss. Considering the variability of the clinical scenario of T.K.A.P.F., this complex injury requires and experienced and comprehensive approach based on both facture fixation and/or revision arthroplasty.

Composition optimization of PLA/PPC/HNT nanocomposites for mandibular fixation plate using single-factor experimental design.

The need to overcome the secondary surgery to remove implanted metal fixation plate leads to the idea of replacing the material with degradable bionanocomposite. In this research, polylactic acid/polypropylene (PLA/PPC) blends incorporated with halloysite nanotubes (HNT) (0-6 wt %) were considered as the candidate material for mandibular fixation plate. A single-factor design using Design Expert software was used to determine 20 different compositions of PLA/PPC/HNT nanocomposites and their mechanical properties were then measured. The optimization of the PLA/PPC/HNT nanocomposite composition was performed based on the nanocomposite's response to Young's modulus, tensile strength, and elongation at break. Further analysis suggested an optimum composition of 92.5/7.5 PLA/PPC with 6 wt % of HNT. The statistical results predicted that there was a 71.7% possibility that the proposed nanocomposite would have the following mechanical properties: Young's modulus of 2.18 GPa, a tensile strength of 64.16 MPa, and an elongation at break of 106.53%.

Forgivingness of an Anteromedially Positioned Small Locked Plate for High Tibial Osteotomy in Case of Overcorrection and Lateral Hinge Fracture.

High tibial osteotomy (HTO) represents a sensible treatment option for patients with moderate unicondylar osteoarthritis of the knee and extraarticular malalignment. The possibility of a continuously variable correction setting and a surgical approach low in complications has meant that the medial opening osteotomy has prevailed over the past decades. The objective of the present study was to determine whether anteromedially positioned small plates are nevertheless forgiving under biomechanically unfavourable conditions (overcorrection and lateral hinge fracture). In this study, a simulated HTO was performed on composite tibiae with a 10-mm wedge and fixed-angle anteromedial osteosynthesis with a small implant. Force was applied axially in a neutral mechanical axis, a slight and a marked overcorrection into valgus, with and without a lateral hinge fracture in each case. At the same time, a physiological gait with a dual-peak force profile and a peak load of 2.4 kN was simulated. Interfragmentary motion and rigidity were determined. The rigidity of the osteosynthesis increased over the cycles investigated. A slight overcorrection into valgus led to the lowest interfragmentary motion, compared with pronounced valgisation and neutral alignment. A lateral hinge fracture led to a significant decrease in rigidity and increase in interfragmentary motion. However, in no case was the limit of 1 mm interfragmentary motion critical for osteotomy healing exceeded. The degree of correction of the leg axis, and the presence of a lateral hinge fracture, have an influence on rigidity and interfragmentary motion. From a mechanically neutral axis ranging up to pronounced overcorrection, the implant investigated offers sufficient stability to allow healing of the osteotomy, even if a lateral hinge fracture is present.

Biomechanical evaluation of combined proximal tibial osteotomy for varus knee osteoarthritis implanted novel designed plate system: Finite element analysis.

BACKGROUND: Combined proximal tibial osteotomy (CPTO) is an innovative and effective procedure for correcting varus knee osteoarthritis (VKOA) with intra- and extra-articular deformity. Here, we designed a novel internal fixation plate system for CPTO and assessed the biomechanical strength of the bone-implant. METHODS: Our newly designed CPTO internal fixation plate system included a specialized plate shape, combination holes, locking screw holes, screw position, and size of fixation. The biomechanical performance of this plate system in CPTO treatment was compared via finite element analysis (FEA) to traditional Tomofix devices implanted in the opening-wedge high tibial osteotomy (OWHTO), tibial condylar valgus osteotomy (TCVO), and CPTO. RESULTS: The tibial wedge stiffness and displacement after CPTO implantation of the novel internal plate fixation increased by 9.6%, which was -65% higher than the CPTO with the Tomofix system. The average stress of the bone, plate, and screws in the CPTO implanted the novel designed plate system compared to the Tomofix system decreased by 12.7%, 1.9%, and 20.3 %, respectively. The device maximum stress and wedge stiffness after CPTO with the novel plate system versus traditional OWHTO and TCVO with the Tomofix system were 255.7 MPa, 204 MPa, 130.4 MPa, and 678.9 N/mm, 660.3 N/mm, 1626.0 N/mm, respectively. CONCLUSIONS: The novel internal fixation plate system usage during CPTO exhibited similar bone-implant biomechanical strength, compared to OWHTO, but with enhanced construct stability.

Progressive Dysphagia in Patient With Cervical Plate Complicated With Posterior Pharyngeal Wall Erosion.

A 58-year-old male patient with a history of Parkinson's disease and solitary cervical spinal sarcoma underwent corpectomy, a fusion of C3-C6 with cervical fixation plate placement, and stereotactic body radiation therapy, presented 18 months following surgery with dysphagia, concomitant with weakness, diplopia. The initial workup in cervical magnetic resonance imaging (MRI) revealed aerodigestive tract soft tissue enhancement. Dysphagia progressed during hospitalization, and the patient was intubated due to aspiration pneumonia and respiratory failure. Further evaluations with esophagogastroduodenoscopy (EGD) revealed posterior pharyngeal wall, upper cervical esophageal erosion, and the presence of a cervical fixation plate in the hypopharynx.

Bone remodeling following mandibular reconstruction using fibula free flap.

To investigate bone remodelling responses to mandibulectomy, a joint external and internal remodelling algorithm is developed here by incorporating patient-specific longitudinal data. The primary aim of this study is to simulate bone remodelling activity in the conjunction region with a fibula free flap (FFF) reconstruction by correlating with a 28-month clinical follow-up. The secondary goal of this study is to compare the long-term outcomes of different designs of fixation plate with specific screw positioning. The results indicated that the overall bone density decreased over time, except for the Docking Site (namely DS1, a region of interest in mandibular symphysis with the conjunction of the bone union), in which the decrease of bone density ceased later and was followed by bone apposition. A negligible influence on bone remodeling outcome was found for different screw positioning. This study is believed to be the first of its kind for computationally simulating the bone turn-over process after FFF maxillofacial reconstruction by correlating with patient-specific follow-up.

Thin patient-specific clavicle fracture fixation plates can mechanically outperform commercial plates: An in silico approach.

Current fixation plates used to operatively stabilize clavicular fractures are suboptimal, leading to reoperation rates up to 53%. Plate irritation, which can be caused by a poor geometric fit and plate thickness, has been found to be an important factor for reoperation. Moreover, muscle attachment sites (MAS) have to be detached occasionally. To improve current surgical clavicle fracture treatment with plate osteosynthesis, a change in plate design is required. The goal of this study was to design a patient-specific clavicle fracture fixation plate that includes geometrical optimization and stiffness determination. Its biomechanical performance has been compared with a commercial plate by examining the geometric fit, anatomical outline, stresses and interfragmentary motion using a finite element analysis with physiological loading and boundary conditions. Evaluation showed a better geometrical fit of the patient-specific plate as well as an improved fracture reduction. Displacements between fracture fragments were lower in case of the patient-specific plate, both when a fracture gap and no fracture gap were present. Results indicate a superior mechanical performance in terms of all investigated outcomes of the patient-specific plate compared to the commercial plate, while better aligning with the patient-specific geometry and without the need for MAS release. Due to the patient-specific geometry and reduced thickness, these fixation plates are expected to decrease the operation time, as intraoperative contouring will become irrelevant, and to decrease reoperation rates as implant irritation will be minimized.

Chemical Polishing of Additively Manufactured, Porous, Nickel-Titanium Skeletal Fixation Plates.

Nickel-titanium (NiTi) alloys have shown promise for a variety of biomedical applications because of their unique properties of shape memory, superelasticity, and low modulus of elasticity (Young's modulus). Nevertheless, NiTi bulk components cannot be easily machined (e.g., CNC, rolling, grinding, casting, or press molding) due to their thermomechanical sensitivity as well as inherent superelasticity and shape memory. Thus, powder bed fusion (PBF) additive manufacturing has been used to successfully fabricate NiTi medical devices that match the geometric and mechanical needs of a particular patient's condition. However, NiTi PBF fabrication leaves unmelted particles from the source powder adhered to external surfaces, which cause minor dimensional inaccuracy, increase the risk of mechanical failure, and once loose, may irritate or inflame surrounding tissues. Therefore, there is a need to develop a chemical polishing (cleaning) technique to remove unmelted powder from the surfaces of PBF-fabricated implants, especially from inner surfaces that are difficult to access with mechanical polishing tools. This technique is especially useful for highly porous devices printed at high resolution. In this study, a chemical polishing method utilizing HF/HNO3 solution was used to remove loosely attached (i.e., unmelted) powder particles from surfaces of porous, skeletal fixation plates manufactured by PBF AM. It was observed that 7 min of polishing in an HF/HNO3 solution comprising 7.5 HF: 50 HNO3: 42.5 H2O enabled successful removal of all relatively loose and unmelted powder particles. A microcomputed tomography study examination found that the volumetric accuracy of the polished skeletal fixation plates was ±10% compared with the computer-aided design (CAD) model from which it was rendered. This postprocessing chemical polishing protocol is also likely to be useful for removing loose powder, while maintaining CAD model accuracy and mechanical stability for other complexly shaped, porous, three-dimensional (3D), printed NiTi devices.

A comparative study of 3D printing and heat-compressing methods for manufacturing the thermoplastic composite bone fixation plate: Design, characterization, and in vitro biomechanical experimentation.

Metallic bone fixations, due to their high rigidity, can cause long-term complications. To alleviate metallic biomaterials' drawbacks, in this research new Glass Fiber/Polypropylene (GF/PP) composite internal fixations were developed, and an investigation of their mechanical behavior was performed through in vitro biomechanical experiments. Short randomly oriented, long unidirectional prepreg, and long unidirectional fiber yarn were considered as reinforcements, and the effects on their mechanical properties of different manufacturing processes, that is, 3D printing and heat-compressing, were investigated. The constructed fixation plates were tested in the transversely fractured diaphysis of bovine tibia under axial compression loading. The overall stiffness and the Von Mises strain field of the fixation plates were obtained within stable and unstable fracture conditions. The samples were loaded until failure to determine their failure loads, strains, and mechanisms. Based on the results, the GF/PP composite fixation plates can provide adequate interfragmentary movement to amplify bone ossification, so they can provide proper support for bone healing. Moreover, their potential for stress shielding reduction and their load-bearing capacity suggest their merits in replacing traditional metallic plates.

Biomechanical evaluation of glass fiber/polypropylene composite bone fracture fixation plates: Experimental and numerical analysis.

Little is known about the impact behavior of composite fixation plate used in the fracture healing of long bones diaphysis. Hence, this study examined polypropylene composite fixation plates using different glass fibers and measured their biomechanical responses under axial impact loading experimentally and numerically. Short randomly oriented, long unidirectional prepregs and fiber yarn of glass were considered as reinforcements, and fixation plates were fabricated through two different heat-compressing and 3D printing processes. Furthermore, assessing the fixation plate structures impact behavior was carried out using in vitro impact test and finite element analysis (FEA). Impact damping behavior, damage mechanisms, and stress and strain pattern of the composite fixation plate structures were obtained under various bone fractures and impact energies. The impact load-time responses and the failure mechanisms demonstrated that fixation plate structures with more plastic behavior and lower stiffness could act as an initial shock absorber and dampen the transmission of axial impact load by distributing the impact energy over time. Therefore, considering the ability of stress shielding and adequate interfragmentary movement which amplifies bone ossification, the proposed Glass Fiber/PP (GF/PP) composite fixation plates could serve as a proper alternative in orthopedics.

Experimental validation of finite element simulation of a new custom-designed fixation plate to treat mandibular angle fracture.

BACKGROUND: The objective of the study was to validate biomechanical characteristics of a 3D-printed, novel-designated fixation plate for treating mandibular angle fracture, and compare it with two commonly used fixation plates by finite element (FE) simulations and experimental testing. METHODS: A 3D virtual mandible was created from a patient's CT images as the master model. A custom-designed plate and two commonly used fixation plates were reconstructed onto the master model for FE simulations. Modeling of angle fracture, simulation of muscles of mastication, and defining of boundary conditions were integrated into the theoretical model. Strain levels during different loading conditions were analyzed using a finite element method (FEM). For mechanical test design, samples of the virtual mandible with angle fracture and the custom-designed fixation plates were printed using selective laser sintering (SLS) and selective laser melting (SLM) printing methods. Experimental data were collected from a testing platform with attached strain gauges to the mandible and the plates at different 10 locations during mechanical tests. Simulation of muscle forces and temporomandibular joint conditions were built into the physical models to improve the accuracy of clinical conditions. The experimental vs the theoretical data collected at the 10 locations were compared, and the correlation coefficient was calculated. RESULTS: The results show that use of the novel-designated fixation plate has significant mechanical advantages compared to the two commonly used fixation plates. The results of measured strains at each location show a very high correlation between the physical model and the virtual mandible of their biomechanical behaviors under simulated occlusal loading conditions when treating angle fracture of the mandible. CONCLUSIONS: Based on the results from our study, we validate the accuracy of our computational model which allows us to use it for future clinical applications under more sophisticated biomechanical simulations and testing.

Susceptibility to biofilm formation on 3D-printed titanium fixation plates used in the mandible: a preliminary study.

Background: In the oral and maxillofacial surgery, fixation plates are commonly used for the stabilization of bone fragments. Additive manufacturing has enabled us to design and create personalized fixation devices that would ideally fit any given fracture. Aim: The aim of the present preliminary study was to assess the susceptibility of 3D-printed titanium fixation plates to biofilm formation. Methods: Plates were manufactured using selective laser melting (SLM) from Ti-6Al-4 V. Reference strains of Streptococcus mutans, Staphyloccocus epidermidis, Staphylococcus aureus, Lactobacillus rhamnosus, and Candida albicans, were tested to evaluate the material's susceptibility to biofilm formation over 48 hours. Biofilm formations were quantified by a colorimetric method and colony-forming units (CFU) quantification. Scanning electron microscopy (SEM) visualized the structure of the biofilm. Results: Surface analysis revealed the average roughness of 102.75 nm and irregular topography of the tested plates. They were susceptible to biofilm formation by all tested strains. The average CFUs were as follows: S. mutans (11.91 x 107) > S.epidermidis (4.45 x 107) > S. aureus (2.3 x 107) > C.albicans (1.22 x 107) > L. rhamnosus (0.78 x 107). Conclusions: The present preliminary study showed that rough surfaces of additively manufactured titanium plates are susceptible to microbial adhesion. The research should be continued in order to compare additively manufactured plates with other commercially available osteotomy plates. Therefore, we suggest caution when using this type of material.

A Review on 3D-Printed Templates for Precontouring Fixation Plates in Orthopedic Surgery.

This paper is a systematic review of the literature on 3D-printed anatomical replicas used as templates for precontouring the fixation plates in orthopedic surgery. Embase, PubMed, Cochrane, Scopus and Springer databases were consulted for information on design study, fracture anatomical location, number of patients, surgical technique, virtual modeling approach and 3D printing process. The initial search provided a total of 496 records. After removing the duplicates, the title and abstract screening, and applying exclusion criteria and citations searching, 30 papers were declared eligible and included in the final synthesis. Seven studies were identified as focusing on retrospective non-randomized series of clinical cases, while two papers presented randomized case control studies. Two main approaches were highlighted in developing 3D-printed anatomical models for precontouring fixation plates: (a.) medical reconstruction, virtual planning and fracture reduction followed by 3D printing the model; (b.) medical reconstruction followed by 3D printing the model of the mirrored uninjured side. Revised studies reported advantages such as surgical time and blood loss reduction, while the reduction quality is similar with that of the conventional surgery. During the last couple of years there was an increase in the number of studies focused on precontouring orthopedic plates using 3D printing technology. Three-dimensionally-printed templates for plate precontouring were mostly used for acetabular fractures. Knowledge on medical virtual modeling and reconstruction is mandatory.

A mechanical study of novel additive manufactured modular mandible fracture fixation plates - Preliminary Study with finite element analysis.✰.

The paper presents an innovative osteofixation system designed for bone fracture stabilization. Its special feature, which makes it different from other similar systems, is the possibility to precisely adjust the implant to the shape of the bone. Such a precise adjustment is particularly important in the case of multiple fractures, where proper stabilization is a condition for restoring bone geometry and thus obtaining the biomechanical function of a given segment of the body lost due to fracture. Based on the tested properties of the implant material, the presented system structure was verified for loading, stress, and share forces in multi-site fractures of the mandible. Numerical tests were performed for three different fracture models: unilateral double fracture of the body of mandible, unilateral double fracture of the body and the angle of mandible, and bilateral fracture of the mandible at the angle and body of the mandible. The results indicate that the proposed system may be used to stabilize broken bone fragments successfully, and the obtained stabilization would allow unrestricted use of the chewing function during bone healing and remodeling. The authors point out the advantages of the proposed implantation method thanks to which it is possible to obtain any shape of the implant and thus stabilize bone fragments in any case.

Study of fixation of a mandibular plate for favourable fractures of the mandibular angle: numerical predictions.

Fractures of the mandibular angle have been well-described and, in most societies, their incidence is decreasing. In this study we analysed the stabilisation of fractures using a single plate (standard or optimised model). The finite element model was developed based on a mandibular computed tomographic scan, together with a miniplate from DePuy Synthes and an optimised plate. Using the finite element model we looked in turn at the four screws for fixation of the standard plate, and the six screws for the optimised plate, in a complete and an incomplete favourable fracture of the mandibular angle, using two screw diameters, 1.5 and 2 mm. The results indicated that a complete fracture is critical, with 10% more strain at the bone holes. The maximum microstrain was found for the 1.5mm diameter, in screws number 2 and 4, with 7270µÎµ and 6872µÎµ in the complete fractures, respectively. There were similar microstrains in screws number 1 and 2 of the optimised plate with six screws showing similar strains. Micromovements in the fracture line achieved 60µÎµ. The position of the screws influences the microstrains along the fracture line, suggesting that the surgeon places the screws along that line at a distance of 2.5 times the diameter of the screw. The optimised geometry with more screws does not prevent screws from loosening.

Biodegradable magnesium alloy (WE43) in bone-fixation plate and screw.

The purpose of the present study was to evaluate the mechanical strength and the absorption rate of WE43 material and to develop an absorbable metallic plate and screw for craniofacial application. The extruded WE43 plate and screw were evaluated using a LeFort I osteotomy canine model of 10 beagle dogs. Animals were divided into two groups: five dogs in the experimental group and five dogs in the control group. µCT was acquired at 4, 12, and 24 weeks. At 24 weeks after the operation, all animals were sacrificed, and histologic evaluation was performed. Swelling and gas formation were observed in three dogs in the experimental groups at 8 weeks. From 12 weeks, infraorbital fistula and inflammation were observed in three dogs in the experimental group, which gradually decreased and disappeared at 24 weeks. Other two dogs showed less gas formation at 12 weeks. The plates were completely absorbed, and gas formation was not observed at 24 weeks in these two dogs. New bone was well formed around the plates and screws in both groups. Histologic examination showed no specific differences between two groups. The mechanical strength of extruded WE43 was sufficient for mid-facial application. Plates and screws made with appropriately treated WE43 have the potential to be useful clinically.