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1.
J Histotechnol ; : 1-5, 2024 Sep 23.
Artículo en Inglés | MEDLINE | ID: mdl-39312273

RESUMEN

The HistoEnder, an inexpensive open-source 3D printer published as an automated histological slide stainer, has been adapted for conventional biological transmission electron microscopy (TEM) batch grid staining. Details are presented of the 3D printed apparatus, assembly, G-code programming, and operation on the 3D printer to post-section stains up to 20 grids through aqueous uranyl acetate, distilled water rinses, and lead stains. TEM Results are identical to manual staining with the advantages of automation using the low cost HistoEnder, apparatus, and equipment.

2.
Cureus ; 16(8): e67431, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-39310565

RESUMEN

Background Although radiographs and computed tomography (CT) images are reviewed before temporary anchorage device (TAD) implantation, implantation of TADs exactly as planned is difficult. This study aimed to evaluate the accuracy of TAD implantation using an original surgical guide fabricated using cone-beam CT data and computer-aided design software. Methodology The study participants included six experienced orthodontists who had implanted ≥20 TADs, and six inexperienced orthodontists who had never implanted a TAD. Maxillary dental typodont models with radiopaque tooth crowns and roots were used. A total of four TADs were implanted on the buccal sides: between the second bicuspid and first molars and between the first and second molars bilaterally. The accuracy of TAD implantation was examined in two groups: in 12 dental typodont models, TAD implantation was performed using a surgical guide (guide group), and in 12 dental typodont models, TAD implantation was performed without a surgical guide (freehand group). All dental typodont models implanted a total of 96 TADs. The TAD position was evaluated using the CT coordinate system and 3D image measurement software. Using the long axis of the TAD as a reference, the distance between the coronal and apical ends of the implanted TAD and those of the planned TAD, i.e., the ideal implantation position, was measured in both groups along the x, y, and z axes. The medians of the values were compared between the groups. Additionally, the presence of root contact was compared between the experienced and inexperienced orthodontists. Results On the x-axis, the linear deviations (median) of the coronal and apical ends of the TAD in the freehand group were 1.06 mm and 1.36 mm, respectively. In contrast, in the guide group, the deviations were 0.65 mm and 0.90 mm, respectively, and the difference was statistically significant (p = 0.002 and p = 0.005, respectively). On the y-axis, the deviations in the freehand group were 1.13 mm and 1.08 mm, respectively. In contrast, the deviations in the guide group were 0.71 mm and 0.79 mm, respectively, and only the coronal deviations were significantly different between the groups (p = 0.006). On the z-axis, the deviations in the freehand group were 1.44 mm and 1.86 mm, respectively. In contrast, the deviations in the guide group were 0.75 mm and 1.16 mm, respectively, and the difference was statistically significant (p = 0.006 and p = 0.002, respectively). Conclusions The use of a surgical guide allowed for more accurate TAD implantation. Additionally, TAD implantation using a guide prevented root damage.

3.
J Forensic Odontostomatol ; 42(2): 76-86, 2024 Aug 29.
Artículo en Inglés | MEDLINE | ID: mdl-39244768

RESUMEN

Although dental patterns are unique, the use of bitemark analysis in personal identification remains controversial. To accurately reproduce and compare three-dimensional models of bitemarks and dental arches, intraoral three-dimensional scans, commonly utilized in clinical dental practice for precise and stable digital impressions, are recommended. This study aims to compare two different techniques for bitemark analysis: a digital method based on the superimposition of digital scans of dental patterns and lesions, and a visual method based on the physical superimposition of impressions and resin casts produced by 3D printing. A sample of 12 volunteers (6 males and 6 females) with a mean age of 26 years was collected as biters. Each subject was asked to bite on custom supports made from semi-rigid water bottles covered with imprintable dental wax. The dental arches and bitemarks were then recorded using an intraoral scanner and dental impressions. Scan superimposition analysis was conducted using CloudCompare software, while resin casts were printed using a 3D printer and physically superimposed on the bitemark impressions by a blind operator, who was not involved in sample collection, bite test execution, prior cast acquisition, or CloudCompare analysis. Both superimposition techniques relied on the selection of 10 corresponding landmarks (on canines and central and lateral incisors of the upper and lower arches) between the dental arches and impressions. The digital superimposition showed an average concordance of 92.5% for the upper arch landmarks and 85% for the lower arch landmarks, with an overall average concordance of 88.8% for both arches combined. In contrast, the visual analysis of resin casts showed an average concordance of 77.5% for the upper arch and 76.7% for the lower arch, with an overall average of 77.1% for both arches combined. In the analysis performed using CloudCompare, the maxillary arch demonstrated the best superimposition, with 4 landmarks (R0, R1, R2, R5) consistently overlapping. The digital analysis outperformed the visual analysis in all four quadrants, particularly in the upper right arch compared to the lower left arch, thereby supporting the integration of digital techniques in forensic applications. Further studies are necessary to validate the digital technique on a larger sample, including subjects with different dental characteristics, bite dynamics, and varying types of supports and substrates.


Asunto(s)
Imagenología Tridimensional , Modelos Dentales , Humanos , Femenino , Masculino , Adulto , Imagenología Tridimensional/métodos , Mordeduras Humanas/diagnóstico por imagen , Impresión Tridimensional , Técnica de Impresión Dental , Arco Dental/diagnóstico por imagen , Arco Dental/anatomía & histología , Programas Informáticos , Procesamiento de Imagen Asistido por Computador/métodos , Odontología Forense/métodos
4.
Artículo en Inglés | MEDLINE | ID: mdl-39298442

RESUMEN

OBJECTIVES: Tracheal regeneration is challenging owing to its unique anatomy and low blood supply. Most tracheal regeneration applications require scaffolds. Herein, we developed bio-three-dimensional-printed scaffold-free artificial tracheas. METHODS: We fabricated bio-three-dimensional-printed artificial tracheas. Their anterior surface comprised hyaline cartilage differentiated from mesenchymal stem cells, and their posterior surface comprised smooth muscle. Human bone marrow-derived mesenchymal stem cells were cultured and differentiated into chondrocytes using fibroblast growth factor-2 and transforming growth factor-beta-3. Initially, horseshoe-shaped spheroids were printed to cover the anterior surface of the artificial trachea, followed by the application of human bronchial smooth muscle cells for the posterior surface. After a 3-week maturing process, the artificial trachea was subjected to histological and immunohistochemical analyses. RESULTS: The anterior surface of the artificial trachea comprised well-differentiated hyaline cartilage from human bone marrow-derived mesenchymal stem cells. Immunohistochemistry revealed that the smooth muscle expressed α-smooth muscle actin and smooth muscle myosin heavy chain 11. CONCLUSIONS: A bio-three-dimensional-printed scaffold-free artificial trachea comprising different tissues at the front and back was successfully fabricated.

5.
Sensors (Basel) ; 24(15)2024 Aug 02.
Artículo en Inglés | MEDLINE | ID: mdl-39124061

RESUMEN

In experiments considering cell handling in microchannels, cell sedimentation in the storage container is a key problem because it affects the reproducibility of the experiments. Here, a simple and low-cost cell mixing device (CMD) is presented; the device is designed to prevent the sedimentation of cells in a syringe during their injection into a microfluidic channel. The CMD is based on a slider crank device made of 3D-printed parts that, combined with a permanent magnet, actuate a stir bar placed into the syringe containing the cells. By using A549 cell lines, the device is characterized in terms of cell viability (higher than 95%) in different mixing conditions, by varying the oscillation frequency and the overall mixing time. Then, a dedicated microfluidic experiment is designed to evaluate the injection frequency of the cells within a microfluidic chip. In the presence of the CMD, a higher number of cells are injected into the microfluidic chip with respect to the static conditions (2.5 times), proving that it contrasts cell sedimentation and allows accurate cell handling. For these reasons, the CMD can be useful in microfluidic experiments involving single-cell analysis.


Asunto(s)
Dispositivos Laboratorio en un Chip , Humanos , Células A549 , Supervivencia Celular , Técnicas Analíticas Microfluídicas/instrumentación , Magnetismo/instrumentación , Separación Celular/instrumentación , Diseño de Equipo , Análisis de la Célula Individual/instrumentación
6.
J Prosthodont Res ; 2024 Jul 19.
Artículo en Inglés | MEDLINE | ID: mdl-39034113

RESUMEN

PURPOSE: This study aimed to analyze how the wall thickness of 3D-printed hollow zirconia teeth affects shape accuracy. METHODS: Datasets with measurement points were created for different artificial teeth resembling the mandibular right first molar (Geomagic Design X, 3D Systems). Reference distances were 9.8 mm for mesio-distal direction (M-D), 10.9 mm for bucco-lingual direction (B-L), 7.0 mm for MB-BB and DB-BB, and 4.5 mm for ML-LB and DL-LB. The outer geometry was identical for all artificial teeth with wall thicknesses of 0.30, 0.50, 0.75, and 1.00 mm. Twenty zirconia teeth were fabricated using a 3D printer (CeraFab 7500 Dental, Lithoz) for each group and sintered before support removal. After performing analog distance measurements using a micrometer screw, the digital distance measurements and angular deviations between measurement points on 3D scans were analyzed. Possible effects were investigated using nonparametric ANOVA, followed by Tukey's honest significant difference (HSD) test for multiple comparisons. RESULTS: The shape accuracy was acceptable for artificial teeth with wall thicknesses of ≥0.5 mm. The largest distance deviation was observed for a wall thickness of 0.3 mm. In particular, DB-BB showed a median deviation of >56.2 µm, which is significantly larger than that for other test groups, ranging from 7.4-9.5 µm (P < 0.05). In most cases, angular deviations were the largest for teeth with 0.3-mm wall thickness (11.6°) and remained below 5.0° for the other test groups. CONCLUSIONS: Acceptable accuracy was obtained for artificial teeth with wall thicknesses of at least 0.5 mm.

7.
Biosens Bioelectron ; 263: 116561, 2024 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-39033654

RESUMEN

The current work shows the advancement of an additive manufactured multiplex immunosensor for the detection of dengue serotypes 1&2 in dengue patients on a single device with the LOD of 12.5 ng/ml. In this work, we created a QR-Code enabled additive manufactured case comprised of a paper-based electrode coated with ZnO NPs, which helps to enhance the detection signal and make it more selective, both serotype antibodies (DENV1-Ab & DENV2-Ab) were employed against DENV serotypes (DENV1-Ag & DENV2-Ag. QR-code technology was also integrated with the established platform to deliver sensor supporting information so that anybody may quickly obtain supporting sensing result details by scanning with a smartphone. The proposed highly advanced platform successfully detected DENV serotypes in dengue patients and showing a wide range of detection from 12.5 to 200 ng/ml with a LOD of 12.5 ng/ml.The results were also validated with conventional testing, i.e., Indirect Fluorescence Antibody Test (IFAT), so the developed multiplex-sensor became more applicable for the detection of DENV serotypes on a single tool having high sensitivity and selectivity, with a potential of commercialization.


Asunto(s)
Anticuerpos Antivirales , Técnicas Biosensibles , Virus del Dengue , Dengue , Serogrupo , Humanos , Dengue/diagnóstico , Dengue/inmunología , Dengue/virología , Dengue/sangre , Técnicas Biosensibles/instrumentación , Técnicas Biosensibles/métodos , Virus del Dengue/aislamiento & purificación , Virus del Dengue/inmunología , Anticuerpos Antivirales/inmunología , Anticuerpos Antivirales/sangre , Inmunoensayo/métodos , Inmunoensayo/instrumentación , Límite de Detección
8.
Front Public Health ; 12: 1408842, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39071151

RESUMEN

Three-dimensional (3D) printers have become popular educational tools in secondary and post-secondary STEM curriculum; however, concerns have emerged regarding inhalation exposures and associated health risks. Current evidence suggests that filament materials and site conditions may cause differences in the chemical profiles and toxicological properties of 3D printer emissions; however, few studies have evaluated exposures directly in the classroom. In this study, we monitored and sampled particulate matter (PM) emitted from acrylonitrile-butadiene-styrene (ABS) and polylactic acid (PLA) filaments during a 3-hour 3D printing session in a high school classroom using aerosol monitoring instrumentation and collection media. To evaluate potential inhalation risks, Multiple Path Particle Dosimetry (MPPD) modeling was used to estimate inhaled doses and calculate in vitro concentrations based on the observed aerosol data and specific lung and breathing characteristics. Dynamic light scattering was used to evaluate the hydrodynamic diameter, zeta potential, and polydispersity index (PDI) of extracted PM emissions dispersed in cell culture media. Small airway epithelial cells (SAEC) were employed to determine cellular viability, genotoxic, inflammatory, and metabolic responses to each emission exposure using MTS, ELISA, and high-performance liquid chromatography-mass spectrometry (HPLC-MS), respectively. Aerosol monitoring data revealed that emissions from ABS and PLA filaments generated similar PM concentrations within the ultrafine and fine ranges. However, DLS analysis showed differences in the physicochemical properties of ABS and PLA PM, where the hydrodynamic diameter of PLA PM was greater than ABS PM, which may have influenced particle deposition rates and cellular outcomes. While exposure to both ABS and PLA PM reduced cell viability and induced MDM2, an indicator of genomic instability, PLA PM alone increased gamma-H2AX, a marker of double-stranded DNA breaks. ABS and PLA emissions also increased the release of pro-inflammatory cytokines, although this did not reach significance. Furthermore, metabolic profiling via high performance liquid chromatography-mass spectrometry (HPLC-MS) and subsequent pathway analysis revealed filament and dose dependent cellular metabolic alterations. Notably, our metabolomic analysis also revealed key metabolites and pathways implicated in PM-induced oxidative stress, DNA damage, and respiratory disease that were perturbed across both tested doses for a given filament. Taken together, these findings suggest that use of ABS and PLA filaments in 3D printers within school settings may potentially contribute to adverse respiratory responses especially in vulnerable populations.


Asunto(s)
Células Epiteliales , Material Particulado , Impresión Tridimensional , Humanos , Células Epiteliales/metabolismo , Material Particulado/toxicidad , Exposición por Inhalación/efectos adversos , Aerosoles , Butadienos , Poliésteres
9.
Pharmaceutics ; 16(6)2024 Jun 08.
Artículo en Inglés | MEDLINE | ID: mdl-38931904

RESUMEN

The aim of this study was to fabricate mini-tablets of polyhedrons containing theophylline using a fused deposition modeling (FDM) 3D printer, and to evaluate the correlation between release kinetics models and their geometric shapes. The filaments containing theophylline, hydroxypropyl cellulose (HPC), and EUDRAGIT RS PO (EU) could be obtained with a consistent thickness through pre-drying before hot melt extrusion (HME). Mini-tablets of polyhedrons ranging from tetrahedron to icosahedron were 3D-printed using the same formulation of the filament, ensuring equal volumes. The release kinetics models derived from dissolution tests of the polyhedrons, along with calculations for various physical parameters (edge, SA: surface area, SA/W: surface area/weight, SA/V: surface area/volume), revealed that the correlation between the Higuchi model and the SA/V was the highest (R2 = 0.995). It was confirmed that using 3D- printing for the development of personalized or pediatric drug products allows for the adjustment of drug dosage by modifying the size or shape of the drug while maintaining or controlling the same release profile.

10.
J Pharm Bioallied Sci ; 16(Suppl 2): S1431-S1432, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38882783

RESUMEN

The aim of this study was to compare the mechanical properties of orthodontic aligners among different commercially available 3D printing devices. Three different 3D printers were included in this study (Formlabs Form 2 3D printer; Moonray S100 printer (Sprintray, Los Angeles, CA, USA); Eden500V Stratasys 3D Printers were used to prepare orthodontic aligners with dental. The central incisors of each aligner were cut, prepared, and evaluated in terms of Martens-Hardness (HM), indentation-modulus (EIT), and elastic-index (ηIT) as per ISO14577-1:2002. Post hoc pairwise comparisons indicated no significant difference in Martens-Hardness (HM), indentation-modulus (EIT), and elastic-index (ηIT) properties in any group. Under the limitations of this study, it may be concluded that the mechanical properties of 3D-printed orthodontic aligners are dependent on the 3D printer used, and thus, differences in their clinical efficacy are anticipated.

11.
Spine Surg Relat Res ; 8(3): 297-305, 2024 May 27.
Artículo en Inglés | MEDLINE | ID: mdl-38868793

RESUMEN

Introduction: To analyze the reliability of the newly developed patient-specific Screw Guide Template (SGT) system as an intraoperative navigation device for spinal screw insertion. Methods: We attempted to place 428 screws for 51 patients. The accuracy of the screw track was assessed by deviation of the screw axis from the preplanned trajectory on postoperative CT. The safety of the screw insertion was evaluated by the bone breach of the screw. The bone diameter available for screw trajectory (DAST) was measured, and the relations to the bone breach were analyzed. Results: In the inserted screws, 98.4% were defined as accurate, and 94.6% were contained in the target bone. In the cervical spine, the screw deviation between breaching (0.57 mm) and contained screws (0.43 mm) did not significantly differ, whereas DAST for breaching screws (3.62 mm) was significantly smaller than contained screws (5.33 mm) (p<0.001). Cervical screws with ≥4.0 mm DAST showed a significantly lower incidence of bone breach (0.4%) than ≤3.9 mm DAST (28.3%) (p<0.001). In the thoracic spine, screw deviation and DAST had significant differences between breaching (1.54 mm, 4.41 mm) and contained (0.75 mm, 6.07 mm) (p<0.001). The incidence of the breach was significantly lower in thoracic screws with ≥5.0 mm (1.9%) than ≤4.9 (21.9%) DAST (p<0.001). Conclusions: This study demonstrated that our SGT system could support precise screw insertion for 98.4% accuracy and 94.6% safety. DAST was recommended to be ≥4.0 and ≥5.0 mm in the cervical and thoracic spines for safe screw insertion.

12.
J Appl Gerontol ; : 7334648241263234, 2024 Jun 20.
Artículo en Inglés | MEDLINE | ID: mdl-38901837

RESUMEN

Reminiscence has been found to be an effective therapy for older adults and researchers and practitioners have identified a range of benefits, from cognitive stimulation to the reconciliation of past experiences. In this qualitative study, the authors explore the experiences of older adults engaged in a technology-enhanced form of reminiscence therapy (RT) using three-dimensional (3D) printed objects from peoples' past. Content analysis of individual interviews with seven participants (n = 7) revealed three themes: (1) positive experiences with the RT intervention; (2) reflections on the use of 3D printed objects; and (3) the development of relationships between participants and researchers. These findings suggest that RT using 3D printed objects can be effective, but only if objects are accurate and if it suits participants' personalities. Researchers and practitioners may find that the use of 3D printed objects can enhance their RT interventions and thereby enrich the lives of older adults.

13.
Sci Total Environ ; 931: 173003, 2024 Jun 25.
Artículo en Inglés | MEDLINE | ID: mdl-38710394

RESUMEN

This study investigated particle and volatile organic compound (VOC) emission rates (ER) from 3D pens, which are increasingly popular in children's toys. Nine filaments and two 3D pens were evaluated using a flow tunnel, a scanning mobility particle sizer, a proton-transfer-reaction time-of-flight mass spectrometer for particles, and a thermal desorption-gas chromatography-mass spectrometer for VOCs. Results showed that the ERs varied with the pen type, filament, and brand. The particle ER was highest for acrylonitrile butadiene styrene (ABS), followed by polylactic acid (PLA) and polycaprolactone (PCL). Notably, ERs of 83 % and 33 % of ABS and PLA filaments exceeded the maximum allowable particle ER (MAER; 5 × 109 particles/min) for 3D printers but were lower than the VOC MAER (173 µg/min in the office). Different filaments emitted diverse VOCs; ABS emitted styrene and benzene, PLA emitted lactide, and PCL emitted phenol. While particle ERs from 3D pens were comparable to those from printers, the total VOC ERs from 3D pens were slightly lower. Caution is warranted when using 3D pens because of potential health risks, especially their prolonged use, proximity to the breathing zone, and usage by children. This study highlights the need for considering particles and VOCs when assessing the safety of 3D pens, emphasizing awareness of potential hazards, particularly in child-oriented settings.


Asunto(s)
Compuestos Orgánicos Volátiles , Compuestos Orgánicos Volátiles/análisis , Monitoreo del Ambiente/métodos , Contaminantes Atmosféricos/análisis , Contaminación del Aire Interior/análisis , Contaminación del Aire Interior/estadística & datos numéricos , Poliésteres/análisis , Impresión Tridimensional , Material Particulado/análisis
14.
Cureus ; 16(4): e59228, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38807807

RESUMEN

Aim Balanced function of the orofacial muscles is important for normal occlusion and dentition; however, patients with malocclusion often present with myofunctional disorder (MFD). Myofunctional therapy (MFT) has received much attention as a method for reducing MFD. Moreover, prefabricated functional appliances (PFAs) have been developed as a method to eliminate abnormal muscle pressure and guide the tongue into the correct position. However, PFAs have disadvantages, such as poor intraoral retention, limited usage time due to discomfort and poor patient compliance, and changes in the axis of the mandibular anterior teeth. Therefore, this study aimed to develop a new custom-made splint-type orthodontic appliance with CAD/CAM technology. Moreover, we evaluated the characteristics of the appliance and conducted functional tests to determine the effects of the appliance on the orofacial muscles and the discomfort associated with its use. Materials and methods Twenty-five volunteers (nine females and 16 males; mean age 28.4 ± 3.4 years) with normal swallowing function were included in the study. Lip-closing strength (LCS), electromyogram during swallowing, oxygen saturation, and pulse rate were measured and compared when the appliance was not worn and when it was worn. In addition, tongue habits were evaluated, and the maximum tongue pressure was measured when the appliance was not worn. The subjects were asked to answer a questionnaire using a numerical rating scale (NRS) regarding discomfort when wearing the appliance. The evaluation items were swallowing difficulty, speaking difficulty, and breathlessness, which were rated on an 11-point scale ranging from 0 to 10. Statistical tests were conducted using IBM SPSS version 28.0.1 (IBM, Armonk, NY, USA) with the Shapiro-Wilk and Levene's test, followed by the Wilcoxon signed rank sum test. The significance level was set at α = 0.05. The measurement error for each measurement item was evaluated using an intraclass correlation coefficient. Results A new custom-made splint-type orthodontic appliance was fabricated for each subject. The fit and retention of the appliance in the mouth were good when fitted, and a comparison of the functional test measurements of 25 subjects with and without the appliance showed that the LCS decreased significantly (p<0.05) before and after wearing the appliance. However, no statistically significant differences were found for the other items. The Mann-Whitney U test regarding the effects of sex, previous orthodontic treatment, or MFT, and oral habits did not statistically significantly influence the effects of wearing the device. In the NRS results, "difficulty swallowing" was observed in half of the subjects, "difficulty breathing" was rarely observed, and "difficulty speaking" was observed in all subjects. Conclusions A novel custom-made splint-type orthodontic appliance was designed and fabricated using digital workflow and 3D printing technology. This appliance was designed to correct oral habits and was made from a new material classified as a class II medical appliance according to the international harmonized classification.

15.
Food Chem ; 454: 139699, 2024 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-38797101

RESUMEN

The production process of fermented black wheat steamed bread is closely related to the overall quality and nutritional content. In this study, we investigated the accuracy, product texture profile and antioxidant activity of fermented black wheat steamed bread samples produced by piston and spiral three-dimensional (3D) printers. The steaming process generally increased the total phenolic content and flavonoid content of the samples. The spiral 3D printer obtained samples with higher accuracy, total phenolic content up to 1960.43 Mg GAE/kg, and higher cellular antioxidant activity (CAA) content. The samples printed by the piston 3D printer showed higher total flavonoid content (575.75 Mg QE/kg), 2, 2'-azobis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) values and 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) values. This study shows that antioxidant-rich health foods can be prepared using 3D printed black wheat flour. The choice of 3D printing method affects the overall quality and nutritional content of the final product.


Asunto(s)
Vapor , Impresión Tridimensional , Antioxidantes/química , Antioxidantes/farmacología , Fenoles/química , Fenoles/farmacología , Células Hep G2 , Humanos , Proliferación Celular/efectos de los fármacos
16.
J Oral Biosci ; 66(2): 339-348, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38750954

RESUMEN

OBJECTIVES: The development of bio-three-dimensional (bio-3D) printers has led to significant advances in regenerative medicine. Three-dimensional constructs, including spheroids, are maintained by extracellular matrix proteins secreted by cells so that the cells can be cultured in conditions closer to the physiological environment. This study aimed to create a useful 3D construct as a model of the dentin-pulp complex. METHODS: We examined the expression patterns of extracellular matrix proteins and cell proliferation areas in a 3D construct created using O9-1 cells derived from cranial neural crest cells of mice. The 3D construct was created by sticking the spheroid cultures onto a needle array using a bio-3D printer. RESULTS: Cell proliferation areas along with characteristic expression of tenascin C and DMP1 were evaluated. The expression of tenascin C and DMP1 was significantly enhanced in the spheroids compared to that in two-dimensional cultures. Moreover, cell proliferation regions and tenascin C expression were confirmed in the outer layer of spheroids in the embryonic stem cell medium, with insignificant DMP1 expression being observed. Interestingly, in a 3D construct cultured in calcification-induction medium, DMP1 expression was promoted, and DMP1-positive cells existed in the outermost layer without overlapping with tenascin C expression. CONCLUSIONS: The extracellular matrix proteins, tenascin C and DMP1, were expressed in a polarized manner in spheroids and 3D constructs, similar to the findings in the dental papilla. Therefore, these 3D constructs show potential as artificial models for studying odontogenesis.


Asunto(s)
Proliferación Celular , Proteínas de la Matriz Extracelular , Cresta Neural , Impresión Tridimensional , Tenascina , Cresta Neural/citología , Cresta Neural/metabolismo , Animales , Ratones , Tenascina/metabolismo , Proteínas de la Matriz Extracelular/metabolismo , Línea Celular , Esferoides Celulares/citología , Esferoides Celulares/metabolismo , Ingeniería de Tejidos/métodos
17.
Biomimetics (Basel) ; 9(4)2024 Apr 17.
Artículo en Inglés | MEDLINE | ID: mdl-38667251

RESUMEN

The use of metamaterials is a good alternative when looking for structures that can withstand compression forces without increasing their weight. In this sense, using nature as a reference can be an appropriate option to design this type of material. Therefore, in this work, a comparative study of a selection of eight representative models of a wide variety of existing solutions, both bioinspired and proposed by various researchers, is presented. These models have been manufactured using stereolithography (SLA) printing, which allows complex geometries to be obtained in a simple way that would be more complicated to achieve by other procedures. Additionally, the manufacturing cost of each model has been determined. The compression tests of the different models have made it possible to evaluate the breaking force and its corresponding deformation. Likewise, a finite element analysis of the manufactured models has been carried out to simulate their behavior under compression, achieving results very similar to those obtained in the experimental tests. In this way, it has been concluded that, among the three-dimensional patterns, the structure called "3D auxetic" is the one that supports the greatest breaking force due to the topographic characteristics of its bar structure. Similarly, among the two-dimensional patterns, the structure called "Auxetic 1", with a topography based on curves, is capable of supporting the greatest deformation in the compression direction before breaking. Moreover, the highest resistance-force-to-cost ratio has been obtained with a "3D auxetic" structure.

18.
J Tissue Eng ; 15: 20417314241244997, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38617462

RESUMEN

The study focused on the effects of a triply periodic minimal surface (TPMS) scaffolds, varying in porosity, on the repair of mandibular defects in New Zealand white rabbits. Four TPMS configurations (40%, 50%, 60%, and 70% porosity) were fabricated with ß-tricalcium phosphate bioceramic via additive manufacturing. Scaffold properties were assessed through scanning electron microscopy and mechanical testing. For proliferation and adhesion assays, mouse bone marrow stem cells (BMSCs) were cultured on these scaffolds. In vivo, the scaffolds were implanted into rabbit mandibular defects for 2 months. Histological staining evaluated osteogenic potential. Moreover, RNA-sequencing analysis and RT-qPCR revealed the significant involvement of angiogenesis-related factors and Hippo signaling pathway in influencing BMSCs behavior. Notably, the 70% porosity TPMS scaffold exhibited optimal compressive strength, superior cell proliferation, adhesion, and significantly enhanced osteogenesis and angiogenesis. These findings underscore the substantial potential of 70% porosity TPMS scaffolds in effectively promoting bone regeneration within mandibular defects.

19.
Diabetes Metab Syndr ; 18(4): 103002, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38615569

RESUMEN

AIMS: Despite numerous studies covering the various features of three-dimensional printing (3D printing) technology, and its applications in food science and disease treatment, no study has yet been conducted to investigate applying 3D printing in diabetes. Therefore, the present study centers on the utilization and impact of 3D printing technology in relation to the nutritional, pharmaceutical, and medicinal facets of diabetes management. It highlights the latest advancements, and challenges in this field. METHODS: In this review, the articles focusing on the application and effect of 3D printing technology on medical, pharmaceutical, and nutritional aspects of diabetes management were collected from different databases. RESULT: High precision of 3D printing in the placement of cells led to accurate anatomic control, and the possibility of bio-printing pancreas and ß-cells. Transdermal drug delivery via 3D-printed microneedle (MN) patches was beneficial for the management of diabetes disease. 3D printing supported personalized medicine for Diabetes Mellitus (DM). For instance, it made it possible for pharmaceutical companies to manufacture unique doses of medications for every diabetic patient. Moreover, 3D printing allowed the food industry to produce high-fiber and sugar-free products for the individuals with DM. CONCLUSIONS: In summary, applying 3D printing technology for diabetes management is in its early stages, and needs to be matured and developed to be safely used for humans. However, its rapid progress in recent years showed a bright future for the treatment of diabetes.


Asunto(s)
Diabetes Mellitus , Impresión Tridimensional , Humanos , Diabetes Mellitus/terapia , Sistemas de Liberación de Medicamentos , Hipoglucemiantes/administración & dosificación , Medicina de Precisión/métodos , Páncreas/citología , Células Secretoras de Insulina/citología
20.
J Prosthodont ; 2024 Mar 21.
Artículo en Inglés | MEDLINE | ID: mdl-38513226

RESUMEN

This technique presents a new fabrication workflow for a three-dimensional (3D) printed custom tray, which duplicates the morphology of the treatment denture for maxillofacial prostheses using an intraoral scanner, computer-aided design (CAD) software, and a 3D printer. A 70-year-old man underwent reconstruction of segmental mandibulectomy for mandibular osteoblastoma, followed by implant placement and secondary surgery. During the surgical treatment, a treatment denture was fabricated to restore oral function and determine the morphology of the definitive denture. To create the definitive denture with the same morphology as the treatment denture a custom tray was fabricated with the denture morphology after chairside adjustments. The oral cavity was scanned using an intraoral scanner, and the data acquired were imported into general-purpose CAD software, adjusted, and imported into a 3D printer to produce the custom tray. This was fitted into the patient's mouth without any issues, and closed tray impressions were made with impression caps for the locator attachments on the implant body. The morphology of the treatment denture was replicated in the definitive denture by making a silicon impression of the cameo surface at the fabrication of the cast after impression making. In this technique, the morphology of the treatment denture was transferred accurately to the definitive implant partial denture by leveraging existing digital technology. This method represents a practical approach for partial denture fabrication, including maxillofacial defects with complex denture configurations.

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