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- Cortical bone thickness of the anterior maxilla using AI segmentationPublication . Pizzurro, Claudia; Marques, Tiago Miguel Santos; Fernandes, Danilo; Araújo, Filipe Miguel Soares Framegas deIntroduction: The thickness of the buccal cortical plate in the anterior maxilla is a critical factor in implantology, orthodontics, and aesthetic dentistry. Cone-beam computed tomography CBCT combined with artificial intelligence (AI)–based segmentation and three-dimensional digital workflows, may facilitate three-dimensional assessment of alveolar bone morphology. Aim: To evaluate buccal cortical bone thickness in the anterior maxillary region using CBCT imaging associated with AI-based segmentation and three-dimensional digital analysis. Materials and Methods: CBCT examinations of patients with anterior maxillary teeth were retrospectively analysed. DICOM files were imported into CoDiagnostiX® software for AI-based segmentation and STL model generation. The obtained models were analysed in Geomagic Control X® through a standardized three-dimensional workflow. Linear measurements of cortical bone thickness were performed at the cervical, middle, and apical thirds of the teeth. Descriptive, inferential, and exploratory statistical analyses were conducted to assess cortical bone distribution and anatomical variability. Results: A total of 44 CBCT examinations were analysed. Considerable anatomical variability was observed in buccal cortical bone thickness. Mean thickness values generally decreased from the apical to the cervical level, with the lowest values observed at the cervical third. Mixed linear model analysis demonstrated a significant effect of root level on cortical bone thickness on both the right (p = 0.003) and left sides (p = 0.042), with significantly greater thickness at the apical level compared with the cervical level (Bonferroni-adjusted p = 0.002). No significant effects of age or sex were identified. On the left side, lateral incisors presented significantly greater cortical thickness than central incisors (p = 0.006). Conclusion: The anterior maxillary region presents a predominance of thin buccal cortical bone associated with considerable anatomical variability. The present study demonstrated the feasibility of a three-dimensional digital workflow that combines CBCT imaging, AI-assisted segmentation, STL model generation, and three dimensional morphometric analysis to assess alveolar bone morphology. The findings of the present study may support more individualized treatment planning in implantology, orthodontics, and aesthetic dentistry.
- Relatório de atividade clínica em ciências médico-cirúrgicasPublication . Santos, João Rafael Pina dos; Couto, Patrícia Sofia SoaresO presente Relatório de Atividade Clínica apresenta o percurso realizado no último ano do Mestrado Integrado em Medicina Dentária, culminando a formação académica e clínica na Clínica Dentária Universitária da Universidade Católica Portuguesa, em Viseu. O documento reúne a atividade clínica desenvolvida ao longo do ano letivo de 2025/2026, com especial foco na área médico-cirúrgica, mais concretamente em Medicina Oral, evidenciando a aplicação prática dos conhecimentos adquiridos e o desenvolvimento de competências essenciais para o exercício profissional. A diversidade de pacientes observados e tratados proporcionou contacto com diferentes realidades clínicas, permitindo aprofundar competências de diagnóstico, planeamento e execução prática de procedimentos médico-dentários. A experiência em Medicina Oral foi particularmente enriquecedora, pelo contacto com lesões da mucosa oral, patologia das glândulas salivares, manifestações orais de doenças sistémicas e situações que exigiram raciocínio clínico diferenciado e diagnóstico histopatológico. A experiência clínica evidenciou a relevância de uma abordagem integrada e multidisciplinar, centrada nas necessidades específicas de cada paciente. Ao longo deste percurso, tornou-se evidente que a área médico-cirúrgica exige, para além da competência técnica, uma sólida capacidade de diagnóstico diferencial, pensamento crítico, responsabilidade ética e sensibilidade para gerir situações de maior complexidade clínica e emocional. A interação constante com os pacientes contribuiu para o desenvolvimento de uma visão mais abrangente da profissão, reforçando a importância da relação médico-dentista/paciente como elemento fundamental para o sucesso terapêutico. Este relatório constitui, assim, não apenas o registo da atividade clínica desenvolvida, mas também o reflexo da evolução académica, científica, técnica e humana alcançada durante a formação pré-graduada, representando uma etapa determinante na transição para o exercício autónomo e responsável da Medicina Dentária.
- Alterações no microbioma oral durante o tratamento da doença periodontalPublication . Marques, Johanna Sampaio; Mendes, Ana Karina da Silva; Marques, Tiago Miguel SantosIntrodução: A doença periodontal é uma doença inflamatória crónica multifatorial, resultante da interação entre a disbiose do microbioma oral e a resposta imunitária do hospedeiro. Apesar dos avanços na classificação clínica da doença, os métodos convencionais de diagnóstico e monitorização baseiam-se essencialmente em parâmetros clínicos, não refletindo as alterações microbiológicas associadas à sua progressão. Neste contexto, a identificação de biomarcadores microbianos poderá constituir uma ferramenta complementar na monitorização da atividade da doença e da resposta ao tratamento. Objetivo: Avaliar a evolução da carga salivar de Eubacterium timidum, Tannerella forsythia e Treponema denticola e a sua relação com os parâmetros clínicos periodontais. Materiais e Métodos: Realizou-se um estudo observacional longitudinal com 21 pacientes avaliados em dois momentos distintos: no diagnóstico e tratamento periodontal não cirúrgico (T0) e na consulta de reavaliação (T1). Foram recolhidas amostras de saliva não estimulada e informação clínica e sociodemográfica. A carga bacteriana das três espécies foi quantificada por qPCR num subgrupo representativo de 12 participantes e correlacionada com os parâmetros clínicos periodontais. Resultados: Os parâmetros clínicos mantiveram-se globalmente estáveis entre T0 e T1, embora com elevada variabilidade interindividual. A análise microbiológica revelou perfis distintos de aumento, diminuição ou manutenção das espécies bacterianas estudadas, sem uma associação linear com a evolução clínica. Em alguns participantes, o aumento da carga bacteriana acompanhou o agravamento dos parâmetros periodontais, enquanto noutros se observaram alterações microbiológicas na ausência de modificações clínicas relevantes. Conclusão: A quantificação salivar de Eubacterium timidum, Tannerella forsythia e Treponema denticola evidenciou uma elevada heterogeneidade entre os participantes, refletindo a natureza multifatorial da doença periodontal. A integração de biomarcadores microbiológicos com os parâmetros clínicos poderá contribuir para uma monitorização mais abrangente da doença periodontal, sendo necessários estudos com amostras de maior dimensão e períodos de seguimento mais uniformes para confirmar a sua utilidade clínica.
- Aplicação da impressão 3D no ensino da anatomia dentária : uma revisão sistemática sobre modelos anatómicos impressosPublication . Fontes, Luana Leal; Marques, Tiago Miguel Santos; Salgado, Helena Cristina Morais Coelho Teixeira; Quezada, Margarida MartinsIntrodução: A impressão tridimensional (3D) tem vindo a assumir um papel cada vez mais relevante na Medicina Dentária, não só pelas suas aplicações clínicas, mas também pelo seu potencial como ferramenta educativa. No contexto do ensino da Anatomia Dentária, os modelos anatómicos impressos em 3D têm sido descritos como recursos pedagógicos capazes de complementar os métodos tradicionais de ensino,
promovendo uma aprendizagem mais interativa e centrada no estudante. Assim, o objetivo desta revisão sistemática foi analisar a evidência científica disponível sobre a utilização de modelos anatómicos impressos em 3D no ensino da Anatomia Dentária. Materiais e Métodos: A presente revisão sistemática foi desenvolvida de acordo com as diretrizes PRISMA. Foi realizada uma pesquisa bibliográfica nas bases de dados
PubMed/MEDLINE®, ScienceDirect® e Scopus®, em janeiro de 2026, com atualização em março de 2026, recorrendo a termos relacionados com impressão 3D, anatomia dentária e educação, sendo a pesquisa complementada por literatura cinzenta. A seleção dos estudos foi efetuada por dois investigadores independentes, de acordo com critérios de inclusão e exclusão previamente definidos. A qualidade metodológica dos estudos foi avaliada através da Checklist for Quasi-Experimental Studies do Joanna Briggs Institute (JBI), tendo a concordância entre investigadores sido
determinada através do coeficiente Kappa de Cohen. Resultados: Foram identificados 948 registos, dos quais 7 cumpriram os critérios de
elegibilidade e foram incluídos na revisão sistemática. De uma forma geral, os estudos incluídos sugerem que os modelos anatómicos impressos em 3D constituem um recurso pedagógico complementar relevante no ensino da Anatomia Dentária. A sua utilização parece contribuir positivamente para a compreensão da morfologia dentária, visualização tridimensional das estruturas anatómicas, desenvolvimento de
competências práticas e aumento da motivação dos estudantes. Adicionalmente, os modelos impressos em 3D apresentam vantagens relacionadas com a padronização anatómica, acessibilidade e possibilidade de repetição dos procedimentos, reduzindo algumas das limitações associadas aos métodos convencionais de ensino. Conclusão: Os modelos anatómicos impressos em 3D representam uma ferramenta pedagógica complementar promissora no ensino pré-clínico da Anatomia Dentária. A evidência atualmente disponível sugere benefícios ao nível da aprendizagem, compreensão anatómica e desenvolvimento de competências práticas. Contudo, os resultados indicam que estes modelos não deverão substituir totalmente os métodos convencionais de ensino, mas sim ser integrados como recursos complementares no processo de ensino-aprendizagem. - Extreme weather disturbance of electrical substations : a geospatial prediction and impact assessment model for PortugalPublication . Bajramaj, Tim; Bertani, NicolòExtreme weather events are an increasing threat to electrical distribution infrastructure, yet data-driven approaches to substation-level disturbance prediction remain scarce, particularly at the most granular level of the high-to-medium voltage interface. This thesis develops and deploys a modular, open-data framework for predicting and contextualising weather-driven disturbances of substations on the Portuguese mainland. A three-type sampling strategy is used to train a calibrated Gradient Boosting classifier, whichachieves 81.3% accuracy, 70.9% recall, and a ROC-AUC of 0.866 on held-out test set of unseen installations. Daily and cumulative precipitation, temperature extremes, and geographic latitude emerge as the dominant disturbance predictors, with isolated 15 kV substations exhibiting disproportionate vulnerability. A self-developed line-length-proportional allocation mechanismassigns parish-level population, enterprise activity, and critical infrastructure exposure to individual substations across all 2,882 parishes, producing a bounded Criticality Index that ranks installations by their socio-economic consequence in case of disturbance. Both models are operationalized in Grid Sentinel PT, an open-source dashboard delivering automated, daily-updated,three-day-ahead disturbance risk forecasts for every substation on the Portuguese mainland. The framework is designed as a transferable blueprint for other European distribution operators.
- Measuring and explaining financial efficiency in brazilian listed firms : evidence from the social pillar and ESG disclosurePublication . Dietinger, Natalie; Wanke, Peter FernandesObjective: This study examines how efficiently publicly listed Brazilian firms transform financial inputs into financial outputs and to what extent the Social Pillar contributes to explaining differences in financial efficiency. Methodology: Financial efficiency scores are estimated using a hybrid Data Envelopment Analysis–Non-negative Matrix Factorization (DEA–NMF) approach with continuously differentiable hyperparameters (ρ, α, τ), selected through automated calibration. Followed by the second stage regression analysis where the efficiency scores are regressed against ESG and sector variables. Findings: The Social Pillar does not show a statistically significant relationship with financial efficiency for the dataset explored. However, Stakeholder Engagement exhibits a positive and significant association with financial efficiency, like the governance Pillar. The Environmental Expenditure variable shows a significantly negative correlation with financial efficiency. Conclusion: While the Social Pillar does not show an effect, Firms should focus their social incentives on their core stakeholders to boost the social pillar and create efficiency within the firm.
- Assessing the impact of next-generation products on the business model resilience of the austrian tobacco monopolyPublication . Prankl, Simon; Rajsingh, PeterThis dissertation assesses the impact of next-generation products (NGPs) on the business model resilience of the Austrian tobacco monopoly, administered by the Monopolverwaltung GmbH through a network of 4,308 licensed retailers (Trafiken). The market has undergone a structural transition from combustible to non-combustible revenue since 2020, accelerated by the Tax Amendment Act 2025. The study employs a mixed-methods triangulation design, combining quantitative time-series analysis (2018–2025) and revenue projections through 2030 with data from twelve semi-structured expert interviews conducted between April and May 2026. The findings confirm a measurable substitution dynamic: the NGP segment grew from 7.7% of total monopoly revenue in 2022 to 16.2% in 2025 and is projected to reach 26.6% by 2030. The margin differential between combustible cigarettes (12.9%) and newly regulated NGP categories (25.0% to 26.7% for specialty shops) embeds an economic incentive for portfolio reconfiguration within the legislative framework. Evaluated against the dynamic capabilities framework, the monopoly demonstrated strong institutional sensing capacity and an effective but operationally constrained seizing response, alongside an incomplete retail-level reconfiguration that risks bifurcating the network. The institution ultimately exhibited adaptive resilience, maintaining its core exclusive distribution function. The study's principal theoretical contribution is the inversion of the regulatory entrepreneurship mechanism, demonstrating that the regulated incumbent, rather than a disruptive entrant, deployed regulatory entrepreneurship tactics to achieve legislative consolidation.
- Two adoption logics, one tool : how and why talent agencies and content creators differ in evaluating AI operating systems in the DACH creator economyPublication . Geesink, Marleen Sophie; Almeida, SílviaThis dissertation examines how and why talent management agencies and individual content creators in the German-speaking Instagram creator economy differ in their evaluation of integrated AI operating systems (AI OS). The question is not whether established adoption frameworks predict who adopts, but where they break down when two structurally distinct actor types confront the same nascent technology. The study draws on the Technology Acceptance Model, the Unified Theory of Acceptance and Use of Technology, Diffusion of Innovations, and the Technology-Organisation-Environment framework as sensitising lenses. A comparative qualitative design analysed eighteen semi-structured interviews with ten individual creators and eight talent management agencies through a two-wave abductive thematic strategy. Participants evaluated a concrete prototype (marlu.ai) as empirical stimulus. Two structurally distinct adoption logics emerge. Adoption intention in this nascent category does not follow directly from perceived usefulness. Agencies and creators are not simply more or less willing to adopt the same tool, but follow different adoption logics. Agencies are often blocked before evaluation begins, because the category itself is not yet recognised in the field. Creators reach evaluation more readily, but they filter usefulness through autonomy, identity, trust, and delegation boundaries. Managed creators occupy a structurally intermediate position between the two logics, and a preliminary vicarious-adoption configuration decouples adopter from recommender. Established frameworks describe what creators evaluate but not what agencies do not. Such nascent markets require constructs operating upstream of the perceived usefulness pathway.
- Governing the hybrid : algorithmic stewardship and the risk of mission drift in carbon ReFi DAOsPublication . Mohamed, Linda Ben; Azevedo, CarlosHybrid organizations face a persistent governance challenge: how to protect their social mission from the market logic they depend on to survive, a displacement the literature terms Mission Drift. Carbon ReFi DAOs attempt to resolve this by encoding mission protection directly into blockchain-based smart contracts, a governance mode this study names Algorithmic Stewardship. This study evaluates the efficacy and structural boundaries of this automated governance framework under competitive market pressures. Situated at the intersection of hybrid organization theory and Web3 governance research, this study deploys a qualitative exploratory design driven by abductive logic. Eight practitioner interviews across five distinct value chain stakeholder clusters were analysed using the Gioia methodology. Findings reveal that Algorithmic Stewardship does not resolve the dual logic tension; it relocates it. The risk relocation chain extends to a fourth step: Algorithm Capture, the incremental modification of mission-protecting parameters through legitimate governance votes. Five structural limits define where the architecture breaks down: the mission encodability limit, the deliberation gap, willingness to believe failure, the trust deficit, and thecompliance enforcement gap. For algorithmic hybrid architectures to preserve their social missions, protocol design must move away from the myth of absolute automation, treating execution as a strategic variable, implementing dual-layered constitutional architectures, and engineering spaces for relational trust.
- The role of persuasion knowledge and self-esteem in consumer responses to influencer marketing : an experimental studyPublication . D'Alessandro, Camilla; Braga, João NizaInfluencer marketing has emerged as a dominant form of digital advertising, yet the psychological mechanisms underlying consumer resistance to it remain poorly understood. This study examined whether the activation of persuasion knowledge reduces purchase intention and product attitudes in an influencer marketing context, and whether self-esteem moderates this relationship.A 3 (Knowledge Condition: Control, Knowledge Activated, No Knowledge Activated) × 2 (Self-Esteem: High, Low) between-subjects experimental design was conducted with 275 participants. Persuasion knowledge was manipulated through an explicit informative message about influencer marketing practices; self-esteem was manipulated using an autobiographical recall task and verified with the Brief Rosenberg Self-Esteem Scale.None of the four hypotheses were supported. The activation of persuasion knowledge did not significantly affect purchase intention or attitude toward the product, and self-esteem did not moderate either relationship. Notably, participants in the control condition, who evaluated the product without influencer mediation, reported descriptively higher purchase intention and more positive product attitudes than those exposed to influencer content, regardless of persuasion knowledge condition. Exploratory regression analyses identified influencer trust, influencer purchase behaviour, and product familiarity as the strongest predictors of consumer outcomes, with influencer opinion accounting for the largest share of variance in the influencer-exposed subsample. These findings suggest that, in transparent persuasion contexts, source credibility may outweigh cognitive awareness as a determinant of consumer responses. Theoretical and managerial implications are discussed, along with limitations and directions for future research.