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1.
Eur J Dent Educ ; 27(4): 773-783, 2023 Nov.
Article in English | MEDLINE | ID: mdl-36271715

ABSTRACT

INTRODUCTION: Dental education is a challenging and demanding field of study as students are expected to acquire various competencies to fulfil their professional requirements after graduation. The objective of this study was to investigate and compare dental students' and clinical staff instructors' perceptions of the preclinical-to-clinical transition training at a Dental School in Santiago, Chile. MATERIAL AND METHODS: Two questionnaires containing 11 quantitative and one qualitative item were developed to assess our year three, four and five (n = 244) dental undergraduate students' challenges when they begin treating patients, and clinical staff (n = 78) perceptions of the preparedness to treat patients of the same students. Both questionnaires were voluntarily and anonymously implemented eight weeks after the beginning of the 2019 academic year. Responses were analysed using a Chi-squared test for each quantitative question, while qualitative comments were studied to form themes and dimensions. RESULTS: A total of 234 (96%) students and 60 (77%) instructors completed their respective questionnaire. There were considerable variations between students in the different years of the programme, as well as between students and staff members. Students and instructors felt the former had enough knowledge to treat patients though it was difficult for them to apply it in clinical practice. Again, both believed they could communicate with patients, but third year students asked for more training on this. Regarding practical skills, fourth- and fifth-year students felt prepared but not third year students, who preferred to work in pairs with senior students, a preference that was shared by the instructors. All student groups asked clinical staff to provide more frequent, constructive and consistent feedback and felt that the difference between simulation and clinical environments and the amount of clinical work to fulfil clinical requirements made them feel stressed. Another mentioned stressor was students' low self-confidence when working with patients. Among the requested improvements, students requested better training on how the dental clinic works to save time. CONCLUSIONS: Preclinical-to-clinical transition training presents several challenges. Some of the problems highlighted by both students and clinical staff members persisted with the transition after three, four and even five years of training, which needs to be addressed.


Subject(s)
Schools, Dental , Students, Dental , Humans , Chile , Education, Dental , Feedback , Clinical Competence , Surveys and Questionnaires
2.
Int Orthod ; 20(3): 100661, 2022 09.
Article in English | MEDLINE | ID: mdl-35764503

ABSTRACT

BACKGROUND: Adult orthodontic treatment has been increasingly popular, and brackets may need to be bonded to provisional crowns, including CAD/CAM crowns. The use of self-adhesive resin cement or light adhesive paste have been suggested with different surface conditioning protocols to improve the adhesion to CAD/CAM PMMA provisional crowns. Objective To determine and compare the in vitro shear bond strength (SBS) of metal brackets bonded to a provisional prosthetic CAD/CAM material after the use of different adhesive cements and surface conditioning protocols. MATERIALS AND METHODS: One hundred twenty Telio® CAD specimens were manufactured in 12 groups (n=10). Each specimen was bonded to a metal bracket and divided according to adhesive technique (3M™Transbond™ XT Light Cure Paste or 3M™RelyX™ U200) surface treatment (macroretentions) and the use of silane. Half of the specimens were thermocycled (5000 cycles, 5°C/55°C water baths). The SBS test was carried out using a shear bond strength tester, and the type of adhesive failure was determined by means of the adhesive remnant index. The data were analysed with the Mann-Whitney test (α=0.05). RESULTS: Statistically significant differences (P<0.001) in SBS were found among the groups. The group with macroretentions, silane, and not thermocycled was the one that obtained the highest average value (17.31±4.89MPa). The lowest average value was the group without macroretentions, without silane, and thermocycled (3.4±3.37MPa). CONCLUSION: The shear bond strength of brackets to provisional prosthetic CAD/CAM materials depended on the type of adhesive, surface treatment, and aging by thermocycling.


Subject(s)
Dental Bonding , Orthodontic Brackets , Adult , Dental Bonding/methods , Dental Cements , Dental Stress Analysis , Humans , Materials Testing , Resin Cements/chemistry , Shear Strength , Silanes , Surface Properties
3.
Dental Press J Orthod ; 25(3): 31-38, 2020 May.
Article in English | MEDLINE | ID: mdl-32844970

ABSTRACT

INTRODUCTION: Orthodontic treatment for adults is currently increasing, and therefore the need to bond brackets to restorations and temporary crowns. The use of CAD/CAM PMMA provisional restorations for orthodontic purposes have not yet been described, and there is currently insufficient information regarding the strength of bracket adhesion. OBJECTIVE: This study aimed at evaluating the effects of thermocycling (TC) and surface treatment on shear bond strength (SBS) of brackets to different provisional materials. METHODS: Forty specimens were made from each material [PMMA (Telio Lab), bis-acryl (Telio CS C&B), and PMMA CAD/CAM (Telio CAD)], sandpapered, and divided according to surface treatment (pumiced or sandblasted) and TC (half of the samples = 1,000 cycles, 5°C/55°C water baths) (n = 10/group). Stainless-steel brackets were bonded to the specimens (using Transbond XT), and SBS testing was performed. Data were analyzed by three-way ANOVA and LSD post-hoc tests (α = 0.05). Failure types were classified with adhesive remnant index (ARI) scores. RESULTS: SBS values ranged from 1.5 to 14.9 MPa. Sandblasted bis-acryl and sandblasted auto-curing PMMA groups presented similar values (p> 0.05), higher than the CAD/CAM material (p< 0.05), with or without TC. When thermocycled, pumiced bis-acryl showed higher SBS than pumiced acrylic (p= 0.005) and CAD/CAM materials (p= 0.000), with statistical difference (p= 0.009). TC showed negative effect (p< 0.05) for sandblasted bis-acryl and pumiced acrylic groups. ARI predominant score was mostly zero (0) for CAD/CAM, 1 and 2 for bis-acryl, and 1 for acrylic groups. CONCLUSION: In general, bis-acryl material showed the highest SBS values, followed by acrylic and CAD/CAM materials, which showed SBS values lower than an optimum strength for bonding brackets.


Subject(s)
Dental Bonding , Orthodontic Brackets , Dental Stress Analysis , Materials Testing , Polymethyl Methacrylate , Resin Cements , Shear Strength , Surface Properties
4.
Dental press j. orthod. (Impr.) ; 25(3): 31-38, May-June 2020. tab, graf
Article in English | LILACS, BBO - Dentistry | ID: biblio-1133665

ABSTRACT

ABSTRACT Introduction: Orthodontic treatment for adults is currently increasing, and therefore the need to bond brackets to restorations and temporary crowns. The use of CAD/CAM PMMA provisional restorations for orthodontic purposes have not yet been described, and there is currently insufficient information regarding the strength of bracket adhesion. Objective: This study aimed at evaluating the effects of thermocycling (TC) and surface treatment on shear bond strength (SBS) of brackets to different provisional materials. Methods: Forty specimens were made from each material [PMMA (Telio Lab), bis-acryl (Telio CS C&B), and PMMA CAD/CAM (Telio CAD)], sandpapered, and divided according to surface treatment (pumiced or sandblasted) and TC (half of the samples = 1,000 cycles, 5°C/55°C water baths) (n = 10/group). Stainless-steel brackets were bonded to the specimens (using Transbond XT), and SBS testing was performed. Data were analyzed by three-way ANOVA and LSD post-hoc tests (α = 0.05). Failure types were classified with adhesive remnant index (ARI) scores. Results: SBS values ranged from 1.5 to 14.9 MPa. Sandblasted bis-acryl and sandblasted auto-curing PMMA groups presented similar values (p> 0.05), higher than the CAD/CAM material (p< 0.05), with or without TC. When thermocycled, pumiced bis-acryl showed higher SBS than pumiced acrylic (p= 0.005) and CAD/CAM materials (p= 0.000), with statistical difference (p= 0.009). TC showed negative effect (p< 0.05) for sandblasted bis-acryl and pumiced acrylic groups. ARI predominant score was mostly zero (0) for CAD/CAM, 1 and 2 for bis-acryl, and 1 for acrylic groups. Conclusion: In general, bis-acryl material showed the highest SBS values, followed by acrylic and CAD/CAM materials, which showed SBS values lower than an optimum strength for bonding brackets.


RESUMO Introdução: Atualmente, a demanda por tratamento ortodôntico em adultos tem aumentado. Consequentemente, também tem aumentado a necessidade de se colar braquetes em restaurações e coroas provisórias. O uso de restaurações provisórias de PMMA CAD/CAM com finalidade ortodôntica ainda não foi descrito e, até a presente data, não há informação suficiente sobre a resistência da colagem dos braquetes a esse tipo de material. Objetivo: O presente estudo teve como objetivo avaliar os efeitos da termociclagem (TC) e do tratamento de superfície sobre a resistência da colagem ao cisalhamento (RC) de braquetes colados em diferentes materiais provisórios. Métodos: Quarenta espécimes foram confeccionados de cada material: resina acrílica PMMA (Telio Lab), resina bisacrílica (Telio CS C&B), e PMMA CAD/CAM (Telio CAD). Em seguida, foram lixados e divididos de acordo com o tratamento de superfície (polidos ou jateados) e TC (metade da amostra - 1.000 ciclos de imersão em água a 5°C e 55°C) (n = 10/grupo). Braquetes de aço inoxidável foram colados aos espécimes (utilizando Transbond XT) e realizou-se o teste de RC. As informações foram analisadas por meio dos testes ANOVA de três vias e post-hoc LSD (α?#8197;= 0,05). Os tipos de falha foram classificados de acordo com os escores do índice de adesivo remanescente (ARI). Resultados: Os valores de RC variaram de 1,5 a 14,9 MPa. Os grupos de resina bisacrílica jateada e de PMMA autopolimerizável jateado apresentaram valores semelhantes (p> 0,05), superiores ao do material CAD/CAM (p< 0,05) com ou sem TC. Quando submetido à TC, o grupo de resina bisacrílica polida apresentou resistência ao cisalhamento maior do que os grupos de resina acrílica polida (p= 0,005) e do material CAD/CAM (p= 0,000), com diferença estatística (p= 0,009). A TC apresentou efeito negativo (p< 0,05) para os grupos de resina bisacrílica jateada e de resina acrílica polida. O escore ARI = 0 foi predominante para o grupo CAD/CAM; os escores 1 e 2, para o grupo resina bisacrílica; e o escore 1, para o grupo resina acrílica. Conclusão: De forma geral, a resina bisacrílica apresentou os maiores valores de RC, seguida da resina acrílica e do material CAD/CAM, que apresentaram valores de RC inferiores à força recomendada para colagem de braquetes.


Subject(s)
Dental Bonding , Orthodontic Brackets , Surface Properties , Materials Testing , Resin Cements , Polymethyl Methacrylate , Shear Strength , Dental Stress Analysis
5.
Quito; s.n; 1998. 99 p. graf, tab.
Thesis in Spanish | LILACS | ID: lil-249643

ABSTRACT

Dentro de los trastornos afectivos del postparto la depresión es el Trastorno mas frecuente, y se puede presentar desde unas pocas horas de iniciado el puerperio hasta los 6 meses posteriores al parto. A estos trastornos depresivos se los ha dividido en tres categorías: El Blues (depresión azul), la Depresión Mayor y Psicosis postparto. El primero es un trastorno muy frecuente, cuya etiología aun no está suficientemente aclarada, sin embargo se piensa que factores biológicos, psicológicos y sociales especiales, pueden conjugarse en la génesis de este trastorno. Nosotros realizamos un estudio proyectivo descriptivo en la ciudad de Ibarra, en el servicio de Ginecoobstetricia, del Hospital Regional "San Vicente de Paul" en 108 mujeres que cursaban el cuarto día postparto y que reunían los criterios de inclusión propuestos en el protocolo de investigación. Para su evaluación clínica tomamos como marco de referencia los criterios diagnósticos de investigación para Trastorno Depresivo del Manual Diagnóstico y Estadístico de la Asociación Norteamericana de Psiquiatría, tercera edición revisada (DSM III-R). Se encontró una prevalencia de Blues total del 38.9 por ciento, y por niveles: Leve 20.4 por ciento, moderada 14.8 por ciento y severa 3.7 por ciento. Se determinó el riesgo relativo para Blues entre las variables planteadas y se encontró en orden descendente de importancia los siguientes factores de riesgo: Bajo nivel de instrucción, desempleadas o dedicadas a las tareas del hoga, Mayores de 35 años, Procedentes de área rural, Presencia de estrés psicosocial durante el embarazo, Mujeres solteras o sin relación estable de pareja...


Subject(s)
Humans , Female , Depression , Hospitals, State , Ecuador
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