João Miguel Rua

Dr. João Miguel Rua

Escola Superior de Saúde Egas Moniz, Almada, Setúbal, Portugal
orcid

Research Focus & Metrics

Academic Career Length

9Years (2018-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

View All Publications
1 July 2018 in The Saudi Dental Journal
Verified
Journal Article
Open access
ILInês Alexandra Dias Lopes
Inês Alexandra Dias Lopes
PMPaulo Jorge Vaz Cardoso Monteiro
Paulo Jorge Vaz Cardoso Monteiro
José João MendesJosé João Mendes
José João Mendes
JRJoão Miguel Rua
João Miguel Rua
Jorge CaldeiraJorge Caldeira
Jorge Caldeira
The aim of this in vitro study was to evaluate the effect of four finishing and polishing protocols in Surface Roughness (Ra) and Surface Gloss (Ga) of two different nanocomposites. In total, 50 disc samples of a nanofilled resin and a nanohybrid resin were prepared. The samples were assigned randomly to one of the five groups to which different polishing protocols were applied. Analysis of surface roughness was performed using an Atomic Force Microscope (AFM), with the gloss evaluated using a gloss meter.Statistical evaluation of the results were analyzed using SPSS software, based on one-way ANOVA parametric tests along with the Welch correction and the Dunnett test for multiple comparisons of the tested protocols. The results evidence the significant influence of the applied Protocol Types and Resin Types on Surface Roughness (Ra) and Surface Gloss (Ga). The multiple comparisons between polishing systems highlight the contrast between the most complex protocol, evidencing the lowest average Ra and the highest value Ga, and control protocol, evidencing the highest average Ra and the lowest percentage Ga. Filtek™ Supreme XT provided the best results in both Ra and Ga, in Protocol 4, while Brilliant Everglow™ performed better in Protocols 2 and 3. Both Ra and Ga are dependent on the type of protocol used, as protocol 4 evidence a higher performance, depending also on the type of resins tested in the research, as nanofilled resin provided the best results. Furthermore, the gloss is influenced significantly by the surface roughness of the composite resin. In order to achieve excellent aesthetic appearance and high durability of the direct restoration, it is important to select initially the appropriate biomaterial for use and then to base preference for a polishing technique on achieving perfect results in the surface texture.

Verified
Journal Article
Open access
PDF file
FFFilipa Freitas
Filipa Freitas
TMTeresa Pinheiro de Melo
Teresa Pinheiro de Melo
António HS DelgadoAntónio HS Delgado
António HS Delgado
PMPaulo Monteiro
Paulo Monteiro
JRJoão Miguel Rua
João Miguel Rua
José João MendesJosé João Mendes
José João Mendes
Surface properties of composites such as roughness and color impact periodontal health and aesthetic outcomes. Novel bulk-fill composites with improved functionality are being introduced and, in light of the existing variety of finishing/polishing procedures, research of their surface properties is warranted. Sixty discs were prepared from bulk-fill composites (Filtek™ Bulk Fill Posterior Restorative and Fill-Up™) and incremental-fill Filtek™ Z250. They were further divided according to different polishing procedures (n = 5): three multi-step polishing procedures or finishing with a bur (control). Surface roughness (Ra) was measured using an atomic force microscope (The AFM Workshop TT-AFM). A spectrophotometer (Spectroshade Micro Optic) was used to determine color stability, after exposure to a coffee solution. Data were analyzed using two-way MANOVA (significance level of 5%). Resin composite type, polishing procedure, and their interaction had a statistically significant effect on surface roughness (p < 0.001) and color change (p < 0.001). Fill-Up™ exhibited the highest surface roughness and greatest color change. Differences in color change were statistically significant (p < 0.001). Filtek™ Bulk Fill registered the lowest surface roughness and color change, after the three-step polishing procedure. Both parameters were significantly correlated (ρ = 0.754, p < 0.001) and found to be material dependent and polishing-procedure dependent. Higher surface roughness relates to greater color changes.

23 February 2025 in Journal of Clinical Medicine
Verified
Journal Article
Open access
PDF file
SLSofia Lobo
Sofia Lobo
IAInês Argolinha
Inês Argolinha
Vanessa MachadoVanessa Machado
Vanessa Machado
João BotelhoJoão Botelho
João Botelho
JRJoão Miguel Rua
João Miguel Rua
José João MendesJosé João Mendes
José João Mendes
Precision in diagnosis is essential for achieving optimal outcomes in prosthodontics, orthodontics, and orthognathic treatments. Virtual articulators provide a sophisticated digital alternative to conventional methods, integrating intraoral scans, facial scans, and cone beam computed tomography (CBCT) to enhance treatment predictability. This review examines advancements in virtual articulator technology, including digital workflows, virtual facebow transfer, and occlusal analysis, with a focus on Artificial Intelligence (AI)-driven methodologies such as machine learning and artificial neural networks. The clinical implications, particularly in condylar guidance and sagittal condylar inclination, are investigated. By streamlining the acquisition and articulation of digital dental models, virtual articulators minimize material handling errors and optimize workflow efficiency. Advanced imaging techniques enable precise alignment of digital maxillary models within computer-aided design and computer-aided manufacturing systems (CAD/CAM), facilitating accurate occlusal simulations. However, challenges include potential distortions during digital file integration and the necessity for robust algorithms to enhance data superimposition accuracy. The adoption of virtual articulators represents a transformative advancement in digital dentistry, with promising implications for diagnostic precision and treatment outcomes. Nevertheless, further clinical validation is essential to ensure the reliable transfer of maxillary casts and refine digital algorithms. Future developments should prioritize the integration of AI to enhance predictive modeling, positioning virtual articulators as a standard tool in routine dental practice, thereby revolutionizing treatment planning and interdisciplinary collaboration. This review explores advancements in virtual articulators, focusing on their role in enhancing diagnostic precision, occlusal analysis, and treatment predictability. It examines digital workflows, AI-driven methodologies, and clinical applications while addressing challenges in data integration and algorithm optimization.

Irina XavierIrina Xavier
Irina Xavier
RERonald L. Ettinger
Ronald L. Ettinger
Luís ProençaLuís Proença
Luís Proença
João BotelhoJoão Botelho
João Botelho
Vanessa MachadoVanessa Machado
Vanessa Machado
José João MendesJosé João Mendes
José João Mendes
The purpose of this study was to examine the presence of geriatric dentistry (GD) in the curricula of worldwide dental schools, and to identify and compare their curriculum content. Eighty-three dental schools (16.4% response rate), from 24 countries, in six continents, completed a 25-item online questionnaire, to assess their GD curriculum, and were included in the study. GD was a mandatory course in 56 dental schools (67.5%), an independent subject in 14 schools (16.9%), and was taught as a series of lectures in 31 schools (37.4%). Clinically, 56 dental schools (67.5%) had some form of mandatory education in GD. The type of school, location and method of presentation were not associated with greater interest in expanding their curriculum in GD (p = 0.256, p = 0.276, and p = 0.919, respectively, using the Chi-square test). We found GD is a curriculum requirement in most of the surveyed dental schools and is becoming more common among dental school curricula. This survey is the first study to present data from dental schools from all continents, using a web-based survey which is a resourceful, less-expensive tool to gather data.

José João MendesJosé João Mendes
José João Mendes
JVJoão Viana
João Viana
FCFilipe Cruz
Filipe Cruz
DPDinis Pereira
Dinis Pereira
SFSílvia Ferreira
Sílvia Ferreira
ADAna Sintra Delgado
Ana Sintra Delgado
We aimed to investigate the association between blood pressure (BP) and tooth loss and the mediation effect of age. A cross-sectional study from a reference dental hospital was conducted from September 2017 to July 2020. Single measures of BP were taken via an automated sphygmomanometer device. Tooth loss was assessed through oral examination and confirmed radiographically. Severe tooth loss was defined as 10 or more teeth lost. Additional study covariates were collected via sociodemographic and medical questionnaires. A total of 10,576 patients were included. Hypertension was more prevalent in severe tooth loss patients than nonsevere tooth lost (56.1% vs. 39.3%, p < 0.001). The frequency of likely undiagnosed hypertension was 43.4%. The adjusted logistic model for sex, smoking habits and body mass index confirmed the association between continuous measures of high BP and continuous measures of tooth loss (odds ratio (OR) = 1.05, 95% CI: 1.03–1.06, p < 0.001). Age mediated 80.0% and 87.5% of the association between periodontitis with both systolic BP (p < 0.001) and diastolic BP (p < 0.001), respectively. Therefore, hypertension and tooth loss are associated, with a consistent mediation effect of age. Frequency of undiagnosed hypertension was elevated. Age, gender, active smoking, and BMI were independently associated with raised BP.

10 March 2022 in Materials
Verified
Journal Article
Open access
PDF file
MAMatilde Almiro
Matilde Almiro
BMBeatriz Marinho
Beatriz Marinho
António HS DelgadoAntónio HS Delgado
António HS Delgado
JRJoão Miguel Rua
João Miguel Rua
PMPaulo Monteiro
Paulo Monteiro
MGMarco Gresnigt
Marco Gresnigt
There is still a lack of consensus concerning the recommended etching concentration, application time and type of silane when bonding lithium disilicate-reinforced glass ceramics manufactured by CAD/CAM. The purpose of this study was thus to conduct an in vitro study which investigates the influence of hydrofluoric acid (HF) concentration, etching time and silane type on the microtensile bond strength (μTBS) of lithium disilicate to resin composites. Thirty-nine IPS e.max CAD blocks were randomly divided between thirteen groups (n = 3). The variables were HF concentration (9.5 or 4.9%), etching time (20 or 60 s) and silane type (Bis-Silane, Monobond Plus and ESPE Sil Silane). The blocks were cut into beams, aged for 10,000 cycles in a thermocycler and submitted to tensile stress to determine μTBS. A control group featuring the Monobond Etch & Prime (MEP) agent that combines etching/silanisation into a simultaneous process was also added. This group was discarded from the analysis due to only having pre-test failures. The data were analysed using a three-way ANOVA (α = 0.05). The HF concentration, etching time and silane type significantly influenced μTBS (p < 0.001). Significant interactions between time and silane type (p = 0.004), HF concentration and silane type (p < 0.001) and among the three factors (p < 0.001) were noted. Etching lithium disilicate with 9.5% HF (60 s), followed by the application of Bis-Silane, resulted in the highest μTBS (16.6 ± 9.0 MPa). The highest concentration and etching time under study, combined with a two-part silane, resulted in the highest bond strength, while the application of MEP showed a complete pre-test failure.