RESUMEN
The development of synthetic bone substitutes that equal or exceed the efficacy of autologous graft remains challenging. In this study, a rat calvarial defect model was used as a reference to investigate the influence of composition and architecture of 3D-printed cement, with or without bioactives, on tissue regeneration. Printable cement pastes were formulated by combining hyaluronic acid and cement precursors. Cementitious scaffolds were printed with 3 different patterns. After 7 weeks of implantation with or without bone marrow, multiparametric qualitative and quantitative assessments were performed using µCT, SEM, and histology. None of the set-up strategies was as efficient as autologous cancellous bone graft to repair calvarial defects. Nonetheless, the presence of scaffold improved the skull vault closure, particularly when the scaffold was soaked in total bone marrow before implantation. No significant effect of scaffold macro-architecture was observed on tissue mineralization. Magnesium phosphate-based scaffolds (MgP) seemed to induce higher bone formation than their calcium-phosphate-based counterparts. They also displayed a quicker biodegradation and sparse remaining material was found after 7 weeks of implantation. Although further improvements are required to reach clinical settings, this study demonstrated the potential of organo-mineral cements for bone regeneration and highlighted the peculiar properties of MgP-based cements.
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Regeneración Ósea , Impresión Tridimensional , Cráneo , Andamios del Tejido , Animales , Regeneración Ósea/efectos de los fármacos , Andamios del Tejido/química , Ratas , Cráneo/efectos de los fármacos , Sustitutos de Huesos/química , Sustitutos de Huesos/farmacología , Fosfatos de Calcio/química , Fosfatos de Calcio/farmacología , Masculino , Cementos para Huesos/farmacología , Cementos para Huesos/química , Fosfatos/química , Osteogénesis/efectos de los fármacos , Microtomografía por Rayos X , Compuestos de MagnesioRESUMEN
BACKGROUND AND OBJECTIVES: 3-Dimensional (3D) printing has become a common tool to aid implant molding for cranioplastic surgery of large skull defects. Until now, 3D printing of cranial implants itself has not been used, mainly because of medicolegal concerns. With a 3D printer developed for printing medical applications and with implant-grade polyetheretherketone (PEEK) filament available, we established a workflow (in compliance with medical device regulations) to 3D print cranial implants for cranioplastic surgery directly at the point of care (POC). Here, we describe the implementation of 3D printing these PEEK implants for cranioplastic surgery at our academic hospital. METHODS: A thorough design and 3D printing process, in accordance with local medical device regulations, was developed. Implants are digitally designed based upon pre- and post-craniectomy cranial computed tomography scans by trained 3D printing experts from the department of medical engineering at our institution. Implants are then produced on a medical 3D printer with implant-grade PEEK filament using the fused filament fabrication process. After postprocessing and steam sterilization, implantation for reconstruction of the skull can be performed. RESULTS: Cranioplastic surgery with a 3D-printed PEEK implant was performed at our institution in a patient with a large frontotemporoparietal skull defect after traumatic brain injury with consecutive decompressive craniectomy. No intra- or post-operative complications occurred. Postoperative cranial computed tomography scans showed perfect reconstruction of precraniectomy skull shape. The aesthetic result was promising and satisfactory to the patient. CONCLUSION: This novel 3D printing workflow enables the production of patient-specific cranial implants from PEEK, to reconstruct large skull defects directly at the POC in accordance with the European Medical Device Regulation. This marks an unprecedented technological and legal advancement, enabling the hospital infrastructure not only to deliver the cranioplastic surgery itself, but also additive manufacturing of the implant directly at the POC.
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Benzofenonas , Cetonas , Sistemas de Atención de Punto , Polietilenglicoles , Polímeros , Impresión Tridimensional , Cráneo , Humanos , Cráneo/cirugía , Prótesis e Implantes , Procedimientos de Cirugía Plástica/métodos , Procedimientos de Cirugía Plástica/instrumentación , Diseño de PrótesisRESUMEN
OBJECTIVE: This study aimed to evaluate the safety and efficacy of skull-femoral traction followed by osteotomy correction in patients with severe spinal scoliosis and split cord malformation. METHODS: We retrospectively analyzed ten cases of severe spinal scoliosis with Pang I type split cord malformation treated between August 2012 and August 2023. Patients underwent skull-femoral traction prior to osteotomy correction. We assessed changes in height, weight, coronal and sagittal Cobb's angles, and physiological indicators such as vital capacity (VC), forced vital capacity (FVC), forced expiratory volume in one second (FEV1), and blood gas levels before, during, and after treatment. RESULTS: Traction duration ranged from 9 to 19 days, with height and weight showing significant increases post-treatment. The coronal Cobb's angle improved from pre-treatment to post-corrective surgery and remained stable at the final follow-up. Similar improvements were observed in the sagittal plane. Physiological indicators such as VC, FVC, and FEV1, as well as blood gas levels, normalized after treatment. Nutritional status, indicated by triceps skinfold thickness, albumin, and transferrin concentrations, also improved. No neurological complications or device-related complications occurred during or after treatment. CONCLUSION: Skull-femoral traction followed by osteotomy correction is a safe and effective treatment for severe spinal scoliosis with split cord malformation, offering an alternative to high-risk procedures.
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Osteotomía , Escoliosis , Cráneo , Tracción , Humanos , Femenino , Escoliosis/cirugía , Osteotomía/métodos , Masculino , Tracción/métodos , Niño , Adolescente , Estudios Retrospectivos , Cráneo/cirugía , Cráneo/anomalías , Resultado del Tratamiento , Fémur/cirugía , Fémur/anomalíasRESUMEN
Despite their distinct embryonic origins, the skull and brain are highly integrated. Understanding the covariation between the skull and brain can shed light on anatomical, cognitive, and behavioral traits in extant and extinct species. Domestic dogs offer a unique opportunity to investigate skull-brain covariation due to their diverse skull morphologies and neural anatomy. To assess this question, we examined T2-weighted MRI studies of 62 dogs from 33 breeds, plus an additional 17 dogs of mixed or unknown breeds. Scans were opportunistically collected from a veterinary teaching hospital of dogs that were referred for neurological examination but did not have grossly observable structural brain abnormalities. As the neurocrania of dogs become broader and shorter, there is a significant decrease in the gray matter volume of the right olfactory bulb, frontal cortex, marginal gyrus, and cerebellum. On the other hand, as the neurocrania of dogs become narrower and longer, there is a significant decrease in the gray matter volume of the olfactory bulb, frontal cortex, temporal cortex, amygdala, hypothalamus, hippocampus, periaqueductal gray, cerebellum, and brainstem. Selective breeding for specific skull shapes may impact canine brain anatomy and function.
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Encéfalo , Imagen por Resonancia Magnética , Cráneo , Animales , Perros/anatomía & histología , Encéfalo/anatomía & histología , Cráneo/anatomía & histología , Cráneo/diagnóstico por imagen , Masculino , Femenino , Sustancia Gris/anatomía & histología , Sustancia Gris/diagnóstico por imagenRESUMEN
OBJECTIVE: MR-guided focused ultrasound (MRgFUS) thalamotomy is an incisionless neurosurgical treatment for patients with medically refractory essential tremor and tremor-dominant Parkinson's disease. A low skull density ratio (SDR) < 0.40 is a known risk factor for treatment failure. The aim of this study was to identify useful sonication strategies for patients with a low SDR < 0.40 by modifying the standard sonication protocol using maximum high-energy sonication while minimizing the number of sonications. METHODS: The authors retrospectively analyzed the effects of modified MRgFUS sonication on low-SDR tremor patients. All patients underwent head CT scans to calculate their SDR. The SDR threshold for MRgFUS thalamotomy was 0.35. The patients in the early series underwent the standard sonication protocol targeting the ventral intermediate nucleus contralateral to the treated hand side. The patients with a low SDR < 0.40 in the late series underwent a modified sonication protocol, in which the number of alignment sonications was minimized and high-energy treatment sonication (> 36,000 J) was used. The authors evaluated the lesion volume the following day and tremor improvement and adverse events 3 and 12 months after the procedure. The sonication patterns between low-SDR patients treated using different sonication protocols were examined using Fisher's exact test. ANOVA was used to examine the lesion volume and tremor improvement in high- and low-SDR patients treated using different sonication protocols. RESULTS: Among 41 patients with an SDR < 0.40, 14 underwent standard sonication and 27 underwent modified sonication. Fewer alignment sonications and high-energy treatment sonications were used in the modified sonication group compared with the standard group (p < 0.001). The duration of modified sonication was significantly shorter than that of standard sonication (p < 0.001). The lesion volume and tremor improvement significantly differed among the high- and low-SDR groups with different sonication protocols (p < 0.001). Low-SDR patients treated using modified sonication protocols had comparable lesion volume and tremor improvement to the high-SDR group. The modified sonication protocol did not significantly increase adverse intraprocedural and postprocedural events. CONCLUSIONS: Minimizing alignment sonications and applying high-energy sonication in early treatment help to create an optimal lesion volume and control tremor in low-SDR patients.
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Temblor Esencial , Enfermedad de Parkinson , Tálamo , Humanos , Temblor Esencial/cirugía , Temblor Esencial/diagnóstico por imagen , Enfermedad de Parkinson/cirugía , Enfermedad de Parkinson/diagnóstico por imagen , Enfermedad de Parkinson/terapia , Femenino , Masculino , Anciano , Persona de Mediana Edad , Estudios Retrospectivos , Tálamo/cirugía , Tálamo/diagnóstico por imagen , Cráneo/cirugía , Cráneo/diagnóstico por imagen , Imagen por Resonancia Magnética/métodos , Resultado del Tratamiento , Anciano de 80 o más Años , Ultrasonido Enfocado de Alta Intensidad de Ablación/métodos , Sonicación/métodos , Procedimientos Neuroquirúrgicos/métodosRESUMEN
Cranioplasty is a reconstructive neurosurgical procedure that fixes the cranial bone defects after the craniotomy for brain surgeries like tumours, aneurysms, arterio-venous malformations, subdural empyemas and hematomas. Personalized 3D-printed implants offer various advantages, including anatomical accuracy, functional restoration, time-sparing surgery, excellent cosmetic outcomes through their impeccable adjustment to cranial vault defects, and better clinical outcomes. PEEK has a meritorious profile in terms of high success rate, low complication rate, fracture resistance and low toxicity profile, high strength, high toughness, and excellent biocompatibility in cranioplasty. On the other hand, the need for more cost-effective yet ideal biomaterials must be met for nations and patients with financial constraints. Nevertheless, this additively manufactured 3D-printed cranial implant marks the dawn of a new era in precision and personalized neurosurgery.
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Benzofenonas , Procedimientos Neuroquirúrgicos , Polímeros , Impresión Tridimensional , Prótesis e Implantes , Cráneo , Humanos , Cráneo/cirugía , Procedimientos Neuroquirúrgicos/métodos , Cetonas , Procedimientos de Cirugía Plástica/métodos , Medicina de Precisión/métodos , Materiales Biocompatibles , Craneotomía/métodos , Polietilenglicoles , NeurocirugiaRESUMEN
The plains vizcacha, Lagostomus maximus, is the only living species in the genus, being notably larger than fossil congeneric species, such as Lagostomus incisus, from the Pliocene of Argentina and Uruguay. Here, we compare the skull growth allometric pattern and sexual dimorphism of L. maximus and L. incisus, relating shape and size changes with skull function. We also test whether the ontogenetic trajectories and allometric trends between both sexes of L. maximus follow the same pattern. A common allometric pattern between both species was the elongation of the skull, a product of the lengthening of rostrum, and chondrogenesis on the spheno-occipitalis synchondrosis and coronalis suture. We also detected a low proportion of skull suture fusion. In some variables, older male specimens did not represent a simple linear extension of female trajectory, and all dimorphic traits were related to the development of the masticatory muscles. Sexual dimorphism previously attributed to L. incisus would indicate that this phenomenon was present in the genus since the early Pliocene and suggests social behaviors such as polygyny and male-male competition. Ontogenetic changes in L. incisus were similar to L. maximus, showing a conservative condition of the genus. Only two changes were different in the ontogeny of both species, which appeared earlier in L. incisus compared to L. maximus: the development of the frontal process of the nasals in a square shape, and the straight shape of the occipital bone in lateral view. Juveniles of L. maximus were close to adult L. incisus in the morphospace, suggesting a peramorphic process. The sequence of suture and synchondroses fusion showed minor differences in temporozygomatica and frontonasalis sutures, indicating major mechanical stress in L. maximus related to size. We suggest a generalized growth path in Chinchillidae, but further analyses are necessary at an evolutionary level, including Lagidium and Chinchilla.
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Fósiles , Caracteres Sexuales , Cráneo , Animales , Cráneo/anatomía & histología , Cráneo/crecimiento & desarrollo , Masculino , Femenino , Fósiles/anatomía & histología , Roedores/anatomía & histología , Roedores/crecimiento & desarrollo , Evolución Biológica , Suturas Craneales/anatomía & histología , Suturas Craneales/crecimiento & desarrolloRESUMEN
Maxillofacial bone defects can severely impact quality of life by impairing physiological functions such as chewing, breathing, swallowing, and pronunciation. Polyether ether ketone (PEEK) is commonly used for the repair of maxillofacial defects due to its mechanical adaptability, while its osteogenic properties still need refinement. Herein, we have utilized the piezoelectric effect exhibited by barium titanate (BTO) under low-intensity pulsed ultrasound (LIPUS) to develop an ultrasound responsive PEEK (PDA@BTO-SPEEK, PBSP) through the mediating effect of polydopamine (PDA), for repairing maxillofacial bone defects. After modification by PDA@BTO, PBSP possesses better hydrophilicity, which is conducive to cell growth and adhesion. Simultaneously, by virtue of the piezoelectric characteristics of BTO, PBSP obtains a piezoelectric coefficient that matches the bone cortex. Notably, when PBSP is stimulated by LIPUS, it can generate stable electricity and effectively accelerate the osteogenic differentiation of osteoblasts through the regulation of the Piezo1-induced calcium (Ca2+) influx and Akt/GSK3ß/ß-catenin pathway. In addition, PBSP presents satisfactory therapeutic effects in rat skull defect models, and its osteogenic efficiency can be further improved under LIPUS stimulation with high tissue penetration. Collectively, PBSP + LIPUS exhibits great potential as a promising alternative strategy for the repair of maxillofacial bone defects.
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Benzofenonas , Glucógeno Sintasa Quinasa 3 beta , Cetonas , Osteogénesis , Polietilenglicoles , Polímeros , Proteínas Proto-Oncogénicas c-akt , Ratas Sprague-Dawley , beta Catenina , Animales , Glucógeno Sintasa Quinasa 3 beta/metabolismo , Polímeros/química , Osteogénesis/efectos de los fármacos , Ratas , Polietilenglicoles/química , Proteínas Proto-Oncogénicas c-akt/metabolismo , Cetonas/química , Cetonas/farmacología , beta Catenina/metabolismo , Diferenciación Celular/efectos de los fármacos , Osteoblastos/efectos de los fármacos , Ondas Ultrasónicas , Indoles/química , Indoles/farmacología , Masculino , Transducción de Señal/efectos de los fármacos , Cráneo/efectos de los fármacos , Titanio/química , Titanio/farmacología , Regeneración Ósea/efectos de los fármacosRESUMEN
Tumor-associated neutrophil (TAN) effects on glioblastoma (GBM) biology remain under-characterized. We show here that neutrophils with dendritic features-including morphological complexity, expression of antigen presentation genes, and the ability to process exogenous peptide and stimulate major histocompatibility complex (MHC)II-dependent T cell activation-accumulate intratumorally and suppress tumor growth in vivo. Trajectory analysis of patient TAN scRNA-seq identifies this "hybrid" dendritic-neutrophil phenotype as a polarization state that is distinct from canonical cytotoxic TANs, and which differentiates from local precursors. These hybrid-inducible immature neutrophils-which we identified in patient and murine glioblastomas-arise not from circulation, but from local skull marrow. Through labeled skull flap transplantation and targeted ablation, we characterize calvarial marrow as a contributor of antitumoral myeloid antigen-presenting cells (APCs), including TANs, which elicit T cell cytotoxicity and memory. As such, agents augmenting neutrophil egress from skull marrow-such as intracalvarial AMD3100, whose survival-prolonging effect in GBM we report-present therapeutic potential.
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Neoplasias Encefálicas , Diferenciación Celular , Células Dendríticas , Glioblastoma , Neutrófilos , Humanos , Animales , Ratones , Neutrófilos/inmunología , Neutrófilos/metabolismo , Glioblastoma/patología , Glioblastoma/inmunología , Glioblastoma/genética , Glioblastoma/metabolismo , Células Dendríticas/inmunología , Células Dendríticas/metabolismo , Neoplasias Encefálicas/patología , Neoplasias Encefálicas/inmunología , Neoplasias Encefálicas/genética , Neoplasias Encefálicas/metabolismo , Cráneo/patología , Cráneo/inmunología , Médula Ósea/patología , Médula Ósea/inmunología , Ratones Endogámicos C57BL , Línea Celular TumoralRESUMEN
Despite the significance of anatomical variability in various specialties, there is currently limited research dedicated to this topic. Most studies focus on the brain, with only a small number examining the human skull, primarily in relation to anatomical variability in childhood. AIM: Therefore, the aim of our work is to determine the individual anatomical variability of the lateral dimensions of the facial section of the adult human skull. MATERIALS AND METHODS: The study included 115 skulls of mature individuals, comprising 35 dry bone specimens from the anatomy museum collection and 80 results from human head CT scans without bone tissue pathologies. To detail the craniometric characteristics of the lateral surface of the facial section of the skull, polygons (polygons) were constructed with dividing of the facial section of the skull is into the orbital-frontal, nasal, and maxillary. The facial profilegram of the skull was formed as a set of predetermined dimensions between facial profile points, presenting a continuous line passing through points gl-n-rhi-ns-pr-id-pg, reflecting the shape, dimensions, and position of the cranial profile of mature adults regardless of sex or cranial type. RESULTS: It was established that the longitudinal anteroposterior dimensions of the facial skull exhibit a certain range of variability in mature individuals depending on gender. For instance, the distance between the points gl-po (glabella-porion) reaches its maximum values in individuals with a brachycranial skull shape, ranging from 107 mm to 130 mm in men and from 104 mm to 128 mm in women. In individuals with a mesocranial skull shape, this parameter gradually decreases to 109-126 mm in men and 107-124 mm in women. A similar decrease is observed in those with a dolichocranial skull shape, where the range is 109-121 mm in men and 109-120 mm in women. The distance between n-po (nasion-porion) in brachycranial and mesocranial individuals remains within 96-123 mm and 102-123 mm, regardless of gender, indicating that this parameter is relatively stable. However, in dolichocranial individuals, this distance decreases to 104-115 mm. CONCLUSIONS: Individual anatomical variability of the anteroposterior lateral dimensions of the facial skeleton in mature individuals has been determined. A more in-depth analysis of the existing range of individual variability in the profile configuration of the facial skull was conducted using sagittal polygons. It was found that the polygons gl-po-n, n-po-rhi, and rhi-po-ns relate to the structure of the bony profile of the orbital-temporal and nasal regions of the facial skull, reflecting the upper, combined orbital-nasal section of the head.
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Cefalometría , Cráneo , Humanos , Femenino , Masculino , Adulto , Cráneo/anatomía & histología , Cráneo/diagnóstico por imagen , Cefalometría/métodos , Tomografía Computarizada por Rayos X , Persona de Mediana Edad , Variación Anatómica , Huesos Faciales/anatomía & histología , Huesos Faciales/diagnóstico por imagenRESUMEN
The prevalence of positional cranial asymmetry has significantly increased since the introduction of the "Back to Sleep" campaign. Some deformities require therapeutic measures, such as growth-guiding head prostheses. The diagnosis is based on the clinical features, a thorough clinical examination and measurement of the infant's head. Prevention includes early education of parents about alternative positioning methods. Early interventions such as positioning therapy and physiotherapy can be effective in mild cases. In severe cases, the use of growth-guiding orthoses is necessary. The treatment and timing are crucial as head growth is highest in the first year of life. Helmet treatment should be started early to achieve optimal results in order to achieve an improvement in the head shape and ear position. Multidisciplinary approaches including physiotherapy and osteopathy are essential.
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Grupo de Atención al Paciente , Humanos , Lactante , Recién Nacido , Modalidades de Fisioterapia , Terapia Combinada/métodos , Plagiocefalia no Sinostótica/terapia , Plagiocefalia no Sinostótica/diagnóstico , Femenino , Masculino , Aparatos Ortopédicos , Cráneo , Dispositivos de Protección de la CabezaRESUMEN
The complex anatomy and biology of craniofacial bones pose difficulties in their effective and precise reconstruction. Injectable hydrogels (IHs) with water-swollen networks are emerging as a shape-adaptive alternative for noninvasively rebuilding craniofacial bones. The advent of versatile nanomaterials (NMs) customizes IHs with strengthened mechanical properties and therapeutically favorable performance, presenting excellent contenders over traditional substitutes. Structurally, NM-reinforced IHs are energy dissipative and covalently crosslinked, providing the mechanics necessary to support craniofacial structures and physiological functions. Biofunctionally, incorporating unique NMs into IH expands a plethora of biological activities, including immunomodulatory, osteogenic, angiogenic, and antibacterial effects, further favoring controllable dynamic tissue regeneration. Mechanistically, NM-engineered IHs optimize the physical traits to direct cell responses, regulate intracellular signaling pathways, and control the release of biomolecules, collectively bestowing structure-induced features and multifunctionality. By encompassing state-of-the-art advances in NM-integrated IHs, this review offers a foundation for future clinical translation of craniofacial bone reconstruction.
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Regeneración Ósea , Huesos Faciales , Hidrogeles , Nanoestructuras , Ingeniería de Tejidos , Hidrogeles/química , Humanos , Nanoestructuras/química , Animales , Regeneración Ósea/efectos de los fármacos , Ingeniería de Tejidos/métodos , Cráneo/efectos de los fármacos , Osteogénesis/efectos de los fármacos , Materiales Biocompatibles/química , Andamios del Tejido/químicaRESUMEN
This research paper explores the advancement of physical models simulating the human skull-brain complex, focusing on applications in simulating mild Traumatic Brain Injury (mTBI). Existing models, especially head forms, lack biofidelity in accurately representing the native structures of the skull, limiting the understanding of intracranial injury parameters beyond kinematic head accelerations. This study addresses this gap by investigating the use of additive manufacturing (AM) techniques to develop biofidelic skull surrogates. Materials such as Polylactic Acid (PLA), a bone-simulant PLA variant, and Hydroxyapatite-coated Poly(methyl methacrylate) (PMMA) were used to create models tested for their flexural modulus and strength. The trabecular bone regions were simulated by adjusting infill densities (30%, 50%, 80%) and print raster directions, optimizing manufacturing parameters for biofidelic performance. Among the tested materials, PLA and its bone-simulating variant printed at 80% infill density with a side (tangential) print orientation demonstrated the closest approximation to the mechanical properties of cranial bone, yielding a mean flexural modulus of 1337.2 MPa and a mean ultimate strength of 56.9 MPa. Statistical analyses showed that infill density significantly influenced the moduli and strength of the printed simulants. Digital Image Correlation (DIC) corroborated the comparable performance of the simulants, showing similar strain and displacement behaviors to native skull bone. Notably, the performance of the manufactured cortical and trabecular regions underscored their crucial role in achieving biofidelity, with the trabecular structure providing critical dampening effects when the native bone is loaded. This study establishes PLA, particularly its bone-simulant variant, as an optimal candidate for cranial bone simulants, offering significant potential for developing more accurate biofidelic head models in mTBI research.
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Cráneo , Fenómenos Biomecánicos , Ensayo de Materiales , Humanos , Poliésteres/química , Polimetil Metacrilato/química , Fenómenos Mecánicos , Cabeza/anatomía & histologíaRESUMEN
In this paper, we investigate the effectiveness of shape completion neural networks as clinical aids in maxillofacial surgery planning. We present a pipeline to apply shape completion networks to automatically reconstruct complete eumorphic 3D meshes starting from a partial input mesh, easily obtained from CT data routinely acquired for surgery planning. Most of the existing works introduced solutions to aid the design of implants for cranioplasty, i.e. all the defects are located in the neurocranium. In this work, we focus on reconstructing defects localized on both neurocranium and splanchnocranium. To this end, we introduce a new dataset, specifically designed for this task, derived from publicly available CT scans and subjected to a comprehensive pre-processing procedure. All the scans in the dataset have been manually cleaned and aligned to a common reference system. In addition, we devised a pre-processing stage to automatically extract point clouds from the scans and enrich them with virtual defects. We experimentally compare several state-of-the-art point cloud completion networks and identify the two most promising models. Finally, expert surgeons evaluated the best-performing network on a clinical case. Our results show how casting the creation of personalized implants as a problem of shape completion is a promising approach for automatizing this complex task.
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Redes Neurales de la Computación , Tomografía Computarizada por Rayos X , Humanos , Imagenología Tridimensional/métodos , Cráneo/diagnóstico por imagen , Cráneo/cirugía , Medicina de Precisión/métodos , Cirugía Bucal/métodos , Cirugía Asistida por Computador/métodosRESUMEN
Cranioplasty is the surgical repair of a bone defect in the skull resulting from a previous operation or injury, which involves lifting the scalp and restoring the contour of the skull with a graft made from material that is reconstructed from scans of the patient's own skull. The paper introduces a 3D printing technology in creating molds, which are filled with polymethyl methacrylate (PMMA) to reconstruct the missing bone part of the skull. The procedure included several steps to create a 3D model in an STL format, conversion into a G-code which is further used to produce the mold itself using a 3D printer. The paper presents our initial experience with 5 patients who undergone cranioplasty utilizing 3D printed molds. Making a patient-specific model is a very complex process and consists of several steps. The creation of a patient-specific 3D model loading of DICOM images obtained by CT scanning, followed by thresholding-based segmentation and generation of a precise 3D model of part of the patient's skull. Next step is creating the G-code models for 3D printing, after which the actual models are printed using Fused Deposition Modeling printer and PLA material. All surgeries showed good match of the missing bone part and part created using 3D printed mold, without additional steps in refinement. In such a way, 3D printing technology helps in creating personalized and visually appealing bone replacements, at a low cost of the final product.
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Procedimientos de Cirugía Plástica , Impresión Tridimensional , Cráneo , Humanos , Cráneo/cirugía , Cráneo/diagnóstico por imagen , Procedimientos de Cirugía Plástica/instrumentación , Procedimientos de Cirugía Plástica/métodos , Polimetil Metacrilato , Tomografía Computarizada por Rayos X , Medicina de Precisión , MasculinoRESUMEN
BACKGROUND: Bone loss of residual alveolar ridges is a great challenge in the field of dental implantology. Deproteinized bovine bone mineral (DBBM) is commonly used for bone regeneration, however, it is loose and difficult to handle in clinical practice. Hyaluronic acid (HA) shows viscoelasticity, permeability and excellent biocompatibility. The aim of this study is to evaluate whether high-molecular-weight (MW) HA combined with DBBM could promote new bone formation in rat calvarial critical size defects (CSDs). MATERIALS AND METHODS: Rat calvarial CSDs (5 mm in diameter) were created. Rats (n = 45) were randomly divided into 3 groups: HA-DBBM compound grafting group, DBBM particles only grafting group and no graft group. Defect healing was assessed by hematoxylin-eosin staining and histomorphometry 2, 4 and 8 weeks postop, followed by Micro-CT scanning 8 weeks postop. Statistical analyses were performed by ANOVA followed by Tukey's post hoc test with P < 0.05 indicating statistical significance. RESULTS: All rats survived after surgery. Histomorphometric evaluation revealed that at 2, 4 and 8 weeks postop, the percentage of newly formed bone was significantly greater in HA-DBBM compound grafting group than in the other two groups. Consistently, Micro-CT assessment revealed significantly more trabecular bone (BV/TV and Tb.N) in HA-DBBM compound group than in the other two groups, respectively (P < 0.05). Moreover, the trabecular bone was significantly more continuous (Tb.Pf) in HA-DBBM compound group than in the other two groups, respectively (P < 0.05). CONCLUSION: HA not only significantly promoted new bone formation in rats calvarial CSDs but also improved the handling ability of DBBM.
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Regeneración Ósea , Sustitutos de Huesos , Ácido Hialurónico , Osteogénesis , Cráneo , Microtomografía por Rayos X , Animales , Ácido Hialurónico/farmacología , Ácido Hialurónico/uso terapéutico , Ratas , Cráneo/cirugía , Cráneo/diagnóstico por imagen , Cráneo/patología , Sustitutos de Huesos/uso terapéutico , Sustitutos de Huesos/farmacología , Osteogénesis/efectos de los fármacos , Regeneración Ósea/efectos de los fármacos , Masculino , Ratas Sprague-Dawley , Distribución Aleatoria , BovinosRESUMEN
Osteoporotic vertebral compression fractures (OVCFs) are the most prevalent fractures among patients with osteoporosis, leading to severe pain, deformities, and even death. This study explored the use of ectopic embryonic calvaria derived mesenchymal stem cells (EE-cMSCs), which are known for their superior differentiation and proliferation capabilities, as a potential treatment for bone regeneration in OVCFs. We evaluated the impact of EE-cMSCs on osteoclastogenesis in a RAW264.7 cell environment, which was induced by the receptor activator of nuclear factor kappa-beta ligand (RANKL), using cytochemical staining and quantitative real-time PCR. The osteogenic potential of EE-cMSCs was evaluated under various hydrogel conditions. An osteoporotic vertebral body bone defect model was established by inducing osteoporosis in rats through bilateral ovariectomy and creating defects in their coccygeal vertebral bodies. The effects of EE-cMSCs were examined using micro-computed tomography (µCT) and histology, including immunohistochemical analyses. In vitro, EE-cMSCs inhibited osteoclast differentiation and promoted osteogenesis in a 3D cell culture environment using fibrin hydrogel. Moreover, µCT and histological staining demonstrated increased new bone formation in the group treated with EE-cMSCs and fibrin. Immunostaining showed reduced osteoclast activity and bone resorption, alongside increased angiogenesis. Thus, EE-cMSCs can effectively promote bone regeneration and may represent a promising therapeutic approach for treating OVCFs.