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1.
Lasers Med Sci ; 38(1): 194, 2023 Aug 26.
Artigo em Inglês | MEDLINE | ID: mdl-37626207

RESUMO

Conventional surface roughening treatments used for silica-based ceramics in order to improve subsequent adhesion become unreliable for zirconia ceramics. Laser conditioning can be a good alternative. The purpose of this in vitro study was to compare conventional (macro) shear bond strength (SBS) values obtained between resin composite and zirconium oxide ceramic samples grouped according to different micromechanical treatments received, and examine differences in surface roughness. One-hundred and fifty disks of sintered zirconia were randomly divided into 5 groups and roughened as follows: (1) Group NOT, no surface treatment; (2) Group APA, abraded with 50-µm aluminum-oxide (Al2O3) particles; (3) Group TBS, abraded with 30-µm aluminum-oxide particles covered with silica; (4) Group CO2, irradiated with a CO2 laser which emitted in continuous wave mode at 3 W of power; and (5) Group FEM, irradiated with a pulsed femtosecond laser, with an incident energy of 10 µJ, a frequency of 1000 Hz, and a fluence of 1.3 kJ/cm2. All surfaces were treated with a MDP-containing adhesive/silane coupling agent mixture upon which were prepared and light polymerized composite resin cylinders. Shear bond strength was measured and samples were observed by scanning electron microscopy (SEM). Statistically significant differences (p < 0.05) were found among all groups, except between CO2 and FEM, which showed the highest adhesion values (15.12 ± 2.35 MPa and 16.03 ± 2.73 MPa). SEM revealed differences in surface patterns. CO2 laser irradiation can be an alternative to sandblasting, although it could also weaken the ceramic. Suitable surface patterns on zirconia ceramics can be obtained with ultrashort pulsed radiation emitted by a pulsed femtosecond laser.


Assuntos
Lasers de Gás , Alumínio , Dióxido de Carbono , Óxido de Alumínio , Cerâmica , Resinas Compostas
2.
Dent J (Basel) ; 11(1)2023 Jan 04.
Artigo em Inglês | MEDLINE | ID: mdl-36661555

RESUMO

The aim of this study was to perform a narrative review to identify the modifications applied to the chemical structure of third- and fourth-generation zirconia ceramics and to determine the influence of these changes on the mechanical and optical properties. A bibliographical search using relevant keywords was conducted in the PubMed® and EBSCO databases. The abstracts and full texts of the resulting articles were reviewed for final inclusion. Fifty-four articles were included in this review. The analyzed topics were: (1) the composition of first- and second-generation zirconia materials (Y-TZP), (2) the behavior of the studied generations in relation to mechanical and optical properties, and (3) the modifications that were carried out on third-generation (5Y-TZP) and fourth-generation (4Y-TZP) zirconia materials. However, studies focusing on these specific characteristics in third- and fourth-generation zirconia materials are scarce. The review shows that there is a lack of sufficient knowledge about the chemical modifications of zirconia in the new generations.

5.
J Dent Educ ; 86(4): 416-424, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-34796479

RESUMO

PURPOSE: The aim of this study was to develop a tool to analyze the ethical dimensions during dental students' decision making, by using case-based learning (CBL). METHODS: Five clinical scenarios involving ethical aspects addressing different moral dilemmas were selected. The cases were then administered to students during a course on ethics, and the students responded using a narrative technique. To analyze the responses, a criterion inspired by Kohlberg's theory of moral development was used. Subsequently, the data were analyzed statistically, and possible associations between the answers and other variables, such as the student's gender and theoretical knowledge of ethics, were evaluated. RESULTS: A total of 260 students participated (182 women and 78 men), and 1300 narratives were analyzed. The reliability of the construct, as tested by the Cronbach's alpha and the homogeneity index, was acceptable (0.7). The validity of the construct was also assessed, suggesting a component analysis. The descriptive analysis suggests a certain tendency to solve moral problems by referring to established norms and laws. Furthermore, the correlation anaylysis suggests the interrelation between dimensions linked to patient integrity and respect for the truth, even though this conclusion is not reflected in the component analysis, which only detects a generic component of moral sensitivity. No significant differences by gender were found in the narratives, nor a strong correlation of the responses with theoretical knowledge on ethics. CONCLUSION: CBL through the narrative method on ethical dilemmas is an effective tool for assessing dental students' moral competencies and their possible interactions with other variables.


Assuntos
Princípios Morais , Estudantes , Odontologia , Feminino , Humanos , Masculino , Resolução de Problemas , Reprodutibilidade dos Testes
6.
Dent J (Basel) ; 9(5)2021 May 17.
Artigo em Inglês | MEDLINE | ID: mdl-34067879

RESUMO

Education currently focuses on improving academic knowledge and clinical skills, but it is also important for students to develop personal and interpersonal skills from the start of their clinical practice. The aim was to evaluate the effect of peer mentoring in third-year students and to gauge the evolution of non-technical skills (NTS) acquisition up to the fifth year. The study groups were selected between September 2015 and May 2018, based on the NTS training they had or had not received: (1) fifth-year students with no training (G1); (2) third-year students mentored in NTS (G2a); and (3) a small group of fifth-year students who became mentors (G2b). A total of 276 students who took part in this study were assessed using a 114-item self-evaluation questionnaire. Data were collected from seven surveys conducted between September 2015 and May 2018, and statistical analysis was performed using one-way ANOVA and Fisher's post-hoc test. G2a improved their non-technical skill acquisition over three years of clinical training up to their fifth year. This group and G2b showed statistically significant differences compared to non-mentored students (G1). Peer mentoring at the beginning of clinical practice is a valid option for training students in non-technical skills.

7.
J Clin Periodontol ; 47(1): 81-100, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31562778

RESUMO

AIM: The present systematic review aimed at assessing the degree of compliance with supportive periodontal/peri-implant therapy as well as identifying patient-related factors that could potentially play a role on patient compliance. METHODS: Electronic and manual literature searches were carried out to assess patient compliance during maintenance. Main outcomes were compliance definition, degree of compliance and patient-related factors. Owing to the heterogeneity of the data reported across the studies, descriptive statistics were performed to shed light on compliance rate and the patient-related factors. RESULTS: A total of 39 articles were included. No consensus regarding the definition of "compliance" was found in the analysed literature. The percentage of fully compliers and non-compliers ranged between 3.3%-86.8% and 1.69%-64.4%, respectively. Smoking habit and history of periodontal disease were found to be associated with patients' compliance. Inadequate information/motivation was found as the main patient-reported reason for non-compliance. CONCLUSIONS: Despite the high variability across studies, compliance with the supportive periodontal/peri-implant maintenance therapy was found to be unsatisfactory. Attitudes, psychological traits and construct associated with compliance remain largely unknown, and still, lack of information and motivation are paramount to be addressed during the periodontal/implant therapy to increase patient compliance.


Assuntos
Implantes Dentários , Cooperação do Paciente , Peri-Implantite , Doenças Periodontais , Humanos , Motivação , Fumar
8.
Clin Oral Implants Res ; 28(6): 662-667, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-27210034

RESUMO

OBJECTIVES: The impact of single implants on oral health-related quality of life (OHRQoL) is scarcely investigated, especially when combined with immediate placement and loading in extraction sockets. The aim was to describe prospectively the changes of OHRQoL with single implants placed in the esthetic zone in healed ridges or in extraction sockets after 5 years. MATERIAL AND METHODS: Ninety-six patients, enrolled at three clinical centers, received 102 single implants placed in a healed ridge (n = 54 implants/50 patients) or in extraction sockets (n = 48 implants/46 patients). Implants were immediately provisionalized, and permanent crowns were cemented after 12 weeks. Oral health impact profile questionnaires (OHIP-14) were completed before surgery, after 1 (provisional crown), 6 (permanent crown), 12 and 60 months, respectively. The overall OHIP-14 score pertains to seven domains with two items each and was assessed on a Likert scale of 0-4 (0 = never and 4 = very often). The evolution of the total OHIP-14 score and changes within all OHIP domains over time and between groups were assessed with a linear mixed-effect model analysis. RESULTS: After 5 years, overall implant survival was 98%. The total OHIP-14 score for both groups combined decreased from 0.50 at baseline to 0.17 at 6 months (P < 0.001), indicative of improvement. For both groups, this remained stable up to 5 years (P = 0.41). However, after 5 years, the total OHIP-14 score revealed a statistically significantly higher improvement in the healed group compared with the extraction group (P = 0.027). CONCLUSION: Missing a single tooth in the maxillary esthetic zone leads to limited OHRQoL problems as reflected by a low overall OHIP score. However, OHRQoL improves less in the extraction group, reflecting that replacing a missing tooth is perceived as more beneficial than replacing a present tooth.


Assuntos
Implantes Dentários para Um Único Dente , Carga Imediata em Implante Dentário , Saúde Bucal , Qualidade de Vida , Adolescente , Adulto , Idoso , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Inquéritos e Questionários , Adulto Jovem
9.
Int J Paediatr Dent ; 22(2): 100-9, 2012 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-21883558

RESUMO

OBJECTIVES: The objectives were to investigate the prevalence of the condition, by using transillumination, in a group of children. Analysed the prevalence with regard to gender, jaw affected, and the teeth that exhibited dysplasia most commonly. METHODS: A sample of 550 children aged 6 to 14 years was selected at the Department of Paediatric Dentistry at the Universitat Internacional de Catalunya, but among those selected only 505 children were eligible for inclusion in the study. The gender and age of the child, number of permanent teeth, number of teeth affected by MIH and their position were registered. RESULTS: Ninety patients (17.85%) had MIH. Of these, 45 were girls (50%) and 45 were boys (50%). A total of 8062 permanent teeth were observed. Of these, 344 (4.2%) were affected by MIH. Of the teeth affected, 198 (57.7%) were located in the maxilla and 146 (42.4%) in the mandible. This result was statistically significant (P = 0.003). CONCLUSIONS: The population studied showed a prevalence of MIH of 17.8%. The presence of the defect did not differ according to sex in this population. Defects were more common among teeth in the maxilla.


Assuntos
Hipoplasia do Esmalte Dentário/epidemiologia , Esmalte Dentário/patologia , Transiluminação/métodos , Adolescente , Criança , Estudos de Coortes , Hipoplasia do Esmalte Dentário/diagnóstico , Hipoplasia do Esmalte Dentário/patologia , Inquéritos de Saúde Bucal , Feminino , Humanos , Masculino , Mandíbula , Maxila , Prevalência , Distribuição por Sexo , Espanha/epidemiologia , Estatísticas não Paramétricas
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