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1.
Dent J (Basel) ; 12(4)2024 Apr 11.
Artículo en Inglés | MEDLINE | ID: mdl-38668015

RESUMEN

Orthodontic mini-implants are devices used for anchorage in various orthodontic treatments. We conducted a pilot study which aimed to observe preliminary trends regarding the impact of heat treatment on the elastic modulus of Ti6Al4V alloy and stainless steel 316L mini-implants. The initial phase involved testing the impact of heat treatment on the mechanical properties of Ti6Al4V alloy and stainless steel 316L mini-implants. MATERIAL AND METHODS: Ten self-drilling mini-implants sourced from two distinct manufacturers (Jeil Medical Corporation® and Leone®) with dimensions of 2.0 mm diameter and 10 mm length were tested. They were separated into two material groups: Ti6Al4V and 316L. Using the CETRUMT-2 microtribometer equipment, indentation testing was conducted employing a diamond-tipped Rockwell penetrator at a constant force of 4.5 N. RESULTS: Slight differences were observed in the elastic modulus of the Ti6Al4V alloy (103.99 GPa) and stainless steel 316L (203.20 GPa) compared to natural bone. The higher elastic moduli of these materials indicate that they are stiffer, which could potentially lead to stress-shielding phenomena and bone resorption. Heat treatment resulted in significant changes in mechanical properties, including elastic modulus reductions of approximately 26.14% for Ti6Al4V and 24.82% for 316L, impacting their performance in orthodontic applications. CONCLUSION: Understanding the effects of heat treatment on these alloys is crucial for optimizing their biomechanical compatibility and longevity in orthodontic treatment. To fully evaluate the effects of heat treatment on mini-implants and to refine their design and efficacy in clinical practice, further research is needed.

2.
Medicina (Kaunas) ; 59(6)2023 May 28.
Artículo en Inglés | MEDLINE | ID: mdl-37374246

RESUMEN

Background and Objectives: Acrylic resins remain the materials of choice for removable prosthesis due to their indisputable qualities. The continuous evolution in the field of dental materials offers practitioners today a multitude of therapeutic options. With the development of digital technologies, including both subtractive and additive methods, workflow has been considerably reduced and the precision of prosthetic devices has increased. The superiority of prostheses made by digital methods compared to conventional prostheses is much debated in the literature. Our study's objective was to compare the mechanical and surface properties of three types of resins used in conventional, subtractive, and additive technologies and to determine the optimal material and the most appropriate technology to obtain removable dentures with the highest mechanical longevity over time. Materials and Methods: For the mechanical tests, 90 samples were fabricated using the conventional method (heat curing), CAD/CAM milling, and 3D printing technology. The samples were analyzed for hardness, roughness, and tensile tests, and the data were statistically compared using Stata 16.1 software (StataCorp, College Station, TX, USA). A finite element method was used to show the behavior of the experimental samples in terms of the crack shape and its direction of propagation. For this assessment the materials had to be designed inside simulation software that has similar mechanical properties to those used for obtaining specimens for tensile tests. Results: The results of this study suggested that CAD/CAM milled samples showed superior surface characteristics and mechanical properties, comparable with conventional heat-cured resin samples. The propagation direction predicted by the finite element analysis (FEA) software was similar to that observed in a real-life specimen subjected to a tensile test. Conclusions: Removable dentures made from heat-cured resins remain a clinically acceptable option due to their surface quality, mechanical properties, and affordability. Three-dimensional printing technology can be successfully used as a provisional or emergency therapeutic solution. CAD/CAM milled resins exhibit the best mechanical properties with great surface finishes compared to the other two processing methods.


Asunto(s)
Diseño Asistido por Computadora , Impresión Tridimensional , Humanos , Ensayo de Materiales , Propiedades de Superficie , Calor
3.
Medicina (Kaunas) ; 58(9)2022 Sep 03.
Artículo en Inglés | MEDLINE | ID: mdl-36143890

RESUMEN

Background and Objectives: To determine whether there are changes in the cephalometric characteristics of the upper airways and hyoid bone, in patients diagnosed with obstructive sleep apnea syndrome (OSAS) compared to a healthy control group. Material and Methods: This retrospective case−control study included 24 patients diagnosed with OSAS (apnea−hypopnea index (AHI) > 5 obtained after polysomnography) and 24 healthy subjects as a control group that completed the STOP-Bang questionnaire to determine whether they had OSAS. Lateral cephalometric examinations were recommended for all these patients. The software used for the cephalogram interpretation was CS 3D Imaging and CS Airway imaging from Carestream Dental. Results: The subjects with OSAS had a smaller superior posterior airway space (SPAS), with an average of 10.32 mm compared to a 12.20 mm mean in the control group (p = 0.03). Patients with OSAS, had a lowered middle airway space (MAS) with a mean of 7.96 mm in the OSAS group and a 10.96 mm mean in the control group (p = 0.00). All the measurements made for the hyoid bone, such as­H-MnP, H-C3, and H-B­showed increased values (means of 26.31 mm, 39.08 mm, 60.05 mm, respectively), for the OSAS group (p = 0.00). Conclusions: Patients suffering from OSAS had reduced dimensions of the SPAS and MAS values. The hyoid bone had a more inferior position in the study group (with increased values for H-MnP, H-C3, and H-B) compared to the control group.


Asunto(s)
Hueso Hioides , Apnea Obstructiva del Sueño , Estudios de Casos y Controles , Cefalometría/métodos , Humanos , Hueso Hioides/diagnóstico por imagen , Estudios Retrospectivos , Apnea Obstructiva del Sueño/diagnóstico por imagen
4.
Medicina (Kaunas) ; 58(6)2022 Jun 16.
Artículo en Inglés | MEDLINE | ID: mdl-35744074

RESUMEN

Background and Objectives: The surface condition of the materials that are used for temporary prostheses influences their microbial colonization, with a direct impact on the oral tissues. This study aims at a comparative analysis of three types of resins for temporary bridges using conventional and digital technologies. The attention was focused on the analysis of the surface characteristics and mechanical strength of these materials. Materials and Methods: The surface condition was assessed for three distinct materials both before and after polishing- heat-curing resin Superpont C + B (SpofaDental, Jicin, Czech Republic) used unconventional technology, Zotion dental milling polymethyl methacrylate (PMMA) block (Zotion, Chongqing, China) for provisional crowns/bridges used in digital subtractive technologies and Freeprint Temp (Detax GmbH & Co. KG, Ettlingen, Germany) resin for temporary crowns and bridges that are used in 3D printing technologies. The two-way ANOVA analysis indicated that polishing leads to a statistically significant increase in roughness coefficients for all the three resins that were tested (p < 0.001). While the highest roughness coefficients were displayed in the 3D cured sample, the largest decrease was reported by the milled sample Results: The results revealed that surface roughness was significantly influenced by both the type of resin that was used (p < 0.001) and the treatment that was induced by finishing and polishing (p < 0.001). Similar p-values were obtained for each of the three resins. Conclusions: The results demonstrated a significant optimization of the surfaces after finishing and polishing and statistically significant differences between the surface parameters and the mechanical properties of the samples. The low values of the roughness and the acceptable values of the mechanical resistance for the conventional samples indicate these materials for the long-term temporary bridge's realization, allowing the correct restoration of the functions and the rehabilitation at the oral level.


Asunto(s)
Resinas Compuestas , Polimetil Metacrilato , Humanos , Estudios Interdisciplinarios , Ensayo de Materiales , Propiedades de Superficie
5.
Rev Med Chir Soc Med Nat Iasi ; 118(3): 833-40, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-25341309

RESUMEN

The consequences of premature loss of temporary teeth are complex, both of functional and morphological order and the clinical presentation depends on multiple factors: the temporary tooth loss rate as compared with permanent tooth eruption sequence and the number and topography of teeth extracted, so the clinical form of edentulous, which can be frontal or lateral, symmetric or asymmetric, isolated or continuous.


Asunto(s)
Arcada Parcialmente Edéntula , Diente Molar , Pérdida de Diente , Diente Primario/patología , Estudios de Casos y Controles , Niño , Humanos , Estadísticas no Paramétricas , Factores de Tiempo , Erupción Dental
6.
Rev Med Chir Soc Med Nat Iasi ; 117(1): 222-6, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-24505919

RESUMEN

UNLABELLED: In recent years there has been a considerable increase in the number of temporary teeth injuries, this variability being determined by multiple etiologic factors, which we need to be aware of, as well as by predisposing conditions. AIM: To characterize the epidemiology, etiology and pathology of specific types of periodontal-dental trauma in a series of preschool children from Iasi County. MATERIAL AND METHODS: The study included a total of 672 subjects aged 3 to 7 years old, from both urban and rural areas of Iasi County. Statistical analysis was performed using STATISTICA software used in medical research. RESULTS: Prevalence of periodontal-dental trauma in the study group was 19.64%. Gender distribution in the study group showed a preponderance of males (62.12%). The risk of periodontal-dental trauma in deciduous teeth was 1.63 times higher in boys compared to girls. Fall accidents (41.67%) closely followed by playground accidents (31.82%) were the most common causes of periodontal-dental trauma in the study group. CONCLUSIONS: The prevalence of temporary dental trauma in the study group was relatively high, requiring the implementation of oral health promotion strategies and prevention programs, primarily addressed to parents and educators.


Asunto(s)
Periodoncio/lesiones , Traumatismos de los Dientes/epidemiología , Diente Primario/lesiones , Accidentes por Caídas/estadística & datos numéricos , Niño , Preescolar , Femenino , Humanos , Masculino , Juego e Implementos de Juego , Prevalencia , Factores de Riesgo , Rumanía/epidemiología , Población Rural/estadística & datos numéricos , Instituciones Académicas , Distribución por Sexo , Traumatismos de los Dientes/etiología , Traumatismos de los Dientes/prevención & control , Población Urbana/estadística & datos numéricos
7.
Rev Med Chir Soc Med Nat Iasi ; 116(4): 1203-8, 2012.
Artículo en Inglés | MEDLINE | ID: mdl-23700912

RESUMEN

UNLABELLED: The SCOTS version of the Developmental Defects of Enamel Index was designed for use in field settings as an add-on to caries prevalence examinations in order to monitor prevalence of enamel defects. AIM: The aim of this study was to determine the prevalence of developmental dental anomalies (DDE) using the SCOTS index and to statistically analyze the distribution of these anomalies. MATERIAL AND METHODS: The study included 240 children aged 7-10 years old, from lasi, Romania. DDE have been evaluated using SCOTS index. RESULTS: DDE prevalence was 9.2% with the highest rate represented by diffuse opacities (SCOTS score 2), followed by demarcated opacities and hypoplasia (SCOTS scores 1 and 3). Most affected were the male children. 61.9% of all affected teeth had an extension defect of less than 1/3 of the tooth surface and 66.7% of lesions were asymmetrical. There was not a statistically significant correlation between the SCOTS score value and children age or sex. Socioeconomic status can be a potential risk factor for DDE. CONCLUSIONS: DDE prevalence was quite low compared with other studies. SCOTS index is suitable for epidemiological screenings and highlights the public health significance of DDE.


Asunto(s)
Caries Dental/epidemiología , Caries Dental/patología , Hipoplasia del Esmalte Dental/epidemiología , Hipoplasia del Esmalte Dental/patología , Dentición Permanente , Pobreza , Estudiantes/estadística & datos numéricos , Niño , Índice CPO , Femenino , Humanos , Masculino , Pobreza/estadística & datos numéricos , Prevalencia , Reproducibilidad de los Resultados , Factores de Riesgo , Rumanía/epidemiología , Instituciones Académicas , Distribución por Sexo
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