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Evolução da terapia com Fibrina Rica em Plaquetas (PRF) na prática odontológica: tubos plásticos sem aditivos como alternativa na produção de PRF, biofuncionalização de hidroxiapatita sintética com Protocolo Progressivo PRO-PRF e uma série de casos

2026-02-10T06:30:24Z

Title: Evolução da terapia com Fibrina Rica em Plaquetas (PRF) na prática odontológica: tubos plásticos sem aditivos como alternativa na produção de PRF, biofuncionalização de hidroxiapatita sintética com Protocolo Progressivo PRO-PRF e uma série de casos Abstract: Platelet-Rich Fibrin (PRF) has emerged as a promising autologous biomaterial in tissue engineering and the biofunctionalization of synthetic materials, particularly in regenerative bone procedures. This thesis aimed to investigate key aspects related to the preparation, characterization, and clinical application of PRF, with emphasis on the use of plastic tubes without additives and the biofunctionalization of synthetic hydroxyapatite (HA) using the third-generation Progressive PRF (PRO-PRF) protocol. In Chapter 1, the density of the fibrin network, platelet aggregates, and cellular morphology of three PRF protocols obtained in glass or plastic tubes, with or without silica coating, were evaluated. Eight volunteers (n = 8) participated in the study, from whom nine blood samples were collected per individual. The samples were divided into three groups according to tube material and centrifuged using the following protocols: Leukocyte- and Platelet-Rich Fibrin (L-PRF – 700 g/12 min), Advanced Platelet-Rich Fibrin (A-PRF – 200 g/14 min), and Advanced Platelet-Rich Fibrin Plus (A-PRF+ – 200 g/8 min). The membranes were analyzed by light microscopy (LM) to assess fibrin and platelet density and by transmission electron microscopy (TEM) for qualitative evaluation of cellular morphology. Membranes obtained from plastic tubes without additives exhibited significantly lower fibrin network density in the L-PRF (p < 0.019) and A-PRF (p < 0.001) protocols. A significantly higher percentage of platelets was observed in membranes produced in plastic tubes without additives, regardless of the protocol used (p < 0.005). Ultrastructural morphology and cellular integrity were preserved in all groups. In Chapter 2, the distribution pattern of HA biofunctionalized with three protocols was investigated: L-PRF, GM350, and PRO-PRF. The study included eight participants (n = 8), with approximately 48 mL of blood collected in six plastic tubes without additives at three different time points. The tubes were divided into three groups according to the centrifugation protocol: L-PRF, GM350 (350 g/15 min), and PRO-PRF (60 g/5 min, 200 g/5 min, and 700 g/5 min). The fluid material was aspirated and transferred to glass containers (5 mL) containing 0.25 g of HA. After polymerization, the clots were compressed to form blocks. Density analysis by micro-computed tomography revealed no significant differences among L-PRF (37.95 ± 0.40), GM350 (39.13 ± 2.29), and PRO-PRF (34.62 ± 4.05; p = 0.132). The PRF/HA ratio, assessed by LM, was significantly lower in PRO-PRF compared with L-PRF (55.14 ± 1.65; p = 0.033) and GM350 (57.10 ± 4.66; p = 0.014). Scanning electron microscopy (SEM) revealed a dense three-dimensional fibrin network integrated with HA. Chapter 3 described a series of four clinical cases involving the application of HA biofunctionalized with PRO-PRF in maxillary sinus floor elevation procedures. Preliminary clinical and tomographic outcomes demonstrated significant vertical bone gain after 120 days (mean: 8.07 mm), and no postoperative complications observed, suggesting that HA biofunctionalization with PRO-PRF represents a safe and promising strategy to enhance tissue repair.

Padronização do diagnóstico em disfunções temporomandibulares: uma análise da aplicação do DC/TMD em contextos acadêmicos, clínicos e desenvolvimento tecnológico.

2026-01-27T06:19:40Z

Title: Padronização do diagnóstico em disfunções temporomandibulares: uma análise da aplicação do DC/TMD em contextos acadêmicos, clínicos e desenvolvimento tecnológico. Abstract: This thesis comprises three interconnected studies with a shared objective: to make the application of the DC/TMD protocol more objective, accessible, and reproducible in dental clinical practice. The overarching aim is to enhance the diagnosis of temporomandibular disorders (TMD) through standardization, technological integration, and professional training. The first study investigated the prevalence of TMD in patients with Parkinson’s Disease and highlighted substantial limitations in applying the DC/TMD in this population. The need for prior administration of the Mini-Mental State Examination (MMSE), along with the requirement for trained professionals, restricts the reproducibility of the protocol in individuals with even mild cognitive impairment. This underscores the need for diagnostic approaches that are both adaptable and straightforward in neurologically affected populations. The second study evaluated the knowledge and confidence of dental students regarding TMD diagnosis and management. Although most students demonstrated solid theoretical knowledge, they reported low confidence in clinical decision-making. A key barrier identified was the limited exposure to structured diagnostic tools like DC/TMD, revealing a disconnect between academic instruction and clinical readiness. Addressing these challenges, the third study developed and validated a diagnostic software based on DC/TMD. Applied to 154 patients, the digital tool showed high agreement with manual diagnoses (Kappa > 0.8), supporting its reliability as a clinical and educational aid. The software proved capable of minimizing diagnostic variability and broadening the reach of standardized protocols, even for users still in training. General conclusion: These studies converge in their pursuit of strategies that promote more accurate, efficient, and consistent use of the DC/TMD protocol. The integration of scientific evidence, clinical education, and technological innovation emerges as a powerful path toward improving TMD diagnosis and ensuring higher quality and equity in dental care.

Efeito do protocolo de cimentação e uso de protetor bucal no desempenho biomecânico de laminados cerâmicos e facetas diretas em resina composta

2025-11-13T06:20:26Z

Title: Efeito do protocolo de cimentação e uso de protetor bucal no desempenho biomecânico de laminados cerâmicos e facetas diretas em resina composta Abstract: Ceramic laminate veneers and direct composite veneers became more popular nowadays, therefore clarifying some topics about the light curing protocol and the interaction between light curing units and luting agents is very important, as well as clarifying aspects about protection of these restorations using mouthguards with and without modifications. The first objective was to evaluate the effect of moving the mono or multiwave light curing units and different exposure times on the degree of conversion and Knoop microhardness of light-cured resin cements with different photoinitiators. The results showed that localized exposure for 40 s resulted in better mechanical properties of the resin cements, unlike the moving LCU protocol and different photoinitiators were not affected by mono or multiwave LCU. The second objective evaluate the presence and thickness of ceramic laminate veneer and the protection with mouthguards with and without antagonist tooth contact by finite element analysis. It was concluded that 4 mm mouthguard generated similar behavior in 0.3 and 1 mm similar to healthy teeth, and the contact with antagonist tooth improved the stress distribution. The third objective evaluated the modification of a mouthguard with hard insert and air-space on the protection of direct composite veneers. Results showed that with the use of mouthguard the strain decreased and the conventional mouthguard presented higher shock absorption, similar to the air-space, on the other side, mouthguard with hard insert presented the lowest shock absorption. The fourth objective was to condense the results of the first three papers and to disclose with a clinical focus for publication in a national journal. The paper resulted on the condensation of the results and generated some guidelines to facilitate clinical application by dentists.

Comportamento biomecânico de implantes extra-estreitos

2025-10-25T06:21:44Z

Title: Comportamento biomecânico de implantes extra-estreitos Abstract: The evolution of implant dentistry has enabled significant advances in the treatment of patients with tooth loss, initially focused on cases of total edentulism. Over time, clinical indications expanded, requiring adaptations to implants, especially regarding their diameter. This led to the emergence of narrow implants and, later, extra-narrow implants, developed to treat regions with severe bone or spatial limitations, such as the anterior areas of the maxilla and mandible, as well as atrophic maxillae. These implants offer a less invasive alternative to bone grafts, especially in patients with contraindications to regenerative procedures, providing rehabilitation with shorter treatment times and lower morbidity. Despite the observed clinical benefits, extra-narrow implants still generate debate regarding their mechanical resistance, especially in areas with high functional demands. Modifications to implant design and the metal alloys used have sought to overcome this limitation. Clinical studies have demonstrated promising results, particularly in overdentures supported by two implants, promoting improvements in masticatory function and quality of life for edentulous patients. However, further long-term studies are needed to consolidate their indication in different types of rehabilitation, especially in posterior regions of the arch. This thesis aims to analyze the mechanical and clinical laboratory behavior of extra-narrow implants with a diameter of 2.9 mm, the Helix GM Narrow® model (Neodent®, Curitiba, PR, Brazil), as well as a systematic review of the survival of reduced-diameter implants. It is written in three chapters, the first being entitled "Influence of the prosthetic interface and the manufacturing metal on the mechanical behavior of two extra-narrow dental implants – In vitro study." The second is entitled "Clinical results of single narrow-diameter implants in areas of low masticatory load: a systematic review." The third is entitled "Survival of extra-narrow implants in aesthetic regions: A clinical study with 12 months of follow-up." In this study, the reduced-diameter implants demonstrated satisfactory performance, both clinically and in laboratory tests.