Clinical trials

The goal of this randomized clinical trial is to assess whether BCP (Biphasic Calcium Phosphate) improves alveolar ridge preservation (ARP) in patients who need tooth extraction. The main question it aims to answer is whether using BCP for alveolar ridge preservation has a positive effect on bone volume compared with natural healing. The main questions it aims to answer are: Does BCP improve ridge preservation compared with natural healing? Researchers will compare BCP grafted sockets to natural healing sockets to see if BCP better preserves ridge volume. Participants will: Have a tooth indicated for extraction. Be assigned to either BCP or natural healing. Undergo CBCT (Cone Beam Computed Tomography) and intra-oral scanning after extraction and after six months of healing to measure horizontal and vertical resorption and bone density.

The goal of this randomized clinical trial is to assess whether β-TCP (Beta-Tricalcium Phosphate) improves alveolar ridge preservation (ARP) in patients who need tooth extraction. The main question it aims to answer is whether using β-TCP for alveolar ridge preservation has a positive effect on bone volume compared with natural healing. The main questions it aims to answer are: Does β-TCP improve ridge preservation compared with natural healing? Researchers will compare β-TCP grafted sockets to natural healing sockets to see if β-TCP better preserves ridge volume. Participants will: Have a tooth indicated for extraction. Be assigned to either β-TCP or natural healing. Undergo CBCT (Cone Beam Computed Tomography) and intra-oral scanning after extraction and after six months of healing to measure horizontal and vertical resorption and bone density.

This study hypothesizes that the SHIELD technique, when combined with a suitable bone graft material, enables successful immediate implant placement in Type 3 extraction sockets with buccal bone dehiscence, regardless of the extent of buccal bone loss. Specifically, it is proposed that the regenerative potential of the SHIELD technique is not significantly affected by the degree of buccal bone dehiscence, whether in compromised sockets (ST3 Subclass B, when a buccal dehiscence is present and extending 1/3 to 2/3 of the total length of the alveolus) or severely compromised sockets (ST3 Subclass C, for severe dehiscence passing more than 2/3 of the facial bone of the alveolus). All in all, this study aims to assess the clinical performance of the CE-approved medical device NOVAMag® SHIELD by evaluating its success rate and long-term suitability for the rehabilitation of edentulous regions in routine clinical settings. It further seeks to generate clinically meaningful evidence supporting the safety and efficacy of magnesium-based biomaterials in the management of complex post-extraction defects. In addition, the study investigates the CE-approved self-tapping conical implant VEGA® + to obtain comprehensive clinical data contributing to post-market surveillance and continuous product evaluation.

The goal of this clinical trial is to learn whether transcranial direct current stimulation (tDCS), a non-invasive brain stimulation, can reduce "craving" and problematic levels of social media/internet use in university students. The main questions it aims to answer are: * Does active tDCS reduce craving to use social media during the intervention period compared with sham stimulation and no stimulation? * Does active tDCS reduce internet/social media addiction severity (measured with the Internet Addiction Test, IAT) compared with sham stimulation and no stimulation, and are any effects still present at follow-up? Researchers will compare three groups-active tDCS, sham tDCS (a simulation where stimulation is stopped after the first seconds), and a control group (no stimulation)-to see whether changes are due to tDCS rather than placebo effects or time. Participants will: * Complete an initial screening and baseline questionnaires (a sociodemographic questionnaire and the IAT). * Be randomly assigned to one of three groups: active tDCS, sham tDCS, or control (no stimulation). * Complete the IAT again after the intervention and again about 5 weeks later (follow-up), along with questions about social media use habits. During intervention, participants in active tDCS and sham tDCS will: * Attend 10 sessions over 2 consecutive weeks (Monday-Friday), with each session lasting about 30 minutes; mobile phone use is not allowed during sessions. * Rate craving on a Visual Analogue Scale (VAS) at the start and end of each session. This study will be conducted with university students in the Greater Lisbon area and will follow double-blind procedures for the active vs sham conditions (participants and researchers will not know the assigned condition until the end of the study).

This exploratory study evaluates the effectiveness of a 12-session Heart Rate Variability Biofeedback (HRV-BFB) protocol in reducing distress and burnout while promoting psychological well-being among Portuguese National Republican Guard (GNR) professionals. Exposed to high occupational stress from unpredictable risks, shift work, and limited resources, these individuals face elevated vulnerability to chronic stress outcomes. The intervention leverages real-time HRV feedback to enhance autonomic regulation, breathing techniques, and emotional self-regulation.

The aim of the study is to investigate the effects of incorporating variability within Resistance Training (RT) methods on the neural adaptations along the corticospinal tract and on neuromuscular function. The literature suggests that RTis one of the most common modalities to enhance and restore muscle function and its practice results in adaptation in neural and morphological adaptations. It is also known that conditions such as ageing and injury have a negative impact on neural drive to the muscles with consequences at motor control level that are not addressed by traditional RT. Recent approaches such as metronome paced strength training have been used to cover this motor control dimension through a greater control and consciousness of movement. However, this methodology tends not to incorporate the inherent variability and complex, fractal-like fluctuations that characterize human movement. The investigators propose that incorporating variability through a fractal-like metronome approach will speed up the neural adaptations which will be useful in injury rehab.

Kinesiophobia, defined as an excessive and irrational fear of physical movement due to perceived vulnerability to injury, has gained significant attention in clinical and scientific communities. This condition can act as a barrier to physical activity, negatively impacting patients' disability, quality of life, and the implementation of rehabilitation programs. It is particularly prevalent after anterior cruciate ligament reconstruction (ACLR), affecting physical function, return to sport rates, and patient performance. While the Tampa Scale for Kinesiophobia (TSK) is considered a gold standard for assessing kinesiophobia, recent studies have raised concerns about its validity, especially in ACLR patients. The TSK may not adequately capture fear of specific sports activities, which is more common in ACLR patients than a general phobia of movement. Some researchers argue for an assessment approach similar to that used for pain experiences, emphasizing the subjective nature of fear. Based on the specific phobia model, assessing kinesiophobia in the presence of a trigger, such as visualizing or confronting the movement associated with the injury, may be more relevant. This approach is supported by evidence showing that sports situations evoking the greatest fear after ACLR are cutting, jumping, and contact. Further research is needed to investigate alternative methodologies for assessing fear of movement in ACLR patients, considering the prevalence and repercussions of kinesiophobia in this population. The objectives of this study are threefold: * To compare the magnitude of kinesiophobia through the TSK, the subjective feeling of fear when visualising feared movements, and the subjective feeling of fear in anticipation of the feared situation. * Evaluate the impact of focusing on feared activities on motor behavior and Autonomic Nervous System (ANS) markers. * To assess the relation between the three methods of assessing fear of movement and indicators of motor behaviour, ANS activity, fear-avoidance beliefs, anxiety, avoidance behaviour, and physical function.

Anterior cruciate ligament (ACL) injuries are among the most prevalent and functionally limiting knee injuries in sports, particularly those that involve pivoting movements. Despite advancements in surgical reconstruction and physical rehabilitation, many athletes continue to exhibit persistent motor control deficits and increased gait variability, both of which are closely linked to a heightened risk of re-injury and long-term joint degeneration. These deficits arise from biomechanical impairments and disrupt proprioceptive input that requires cortical reorganization, contributing to maladaptive neuroplasticity. However, conventional rehabilitation strategies often overlook this neural dimension. Recent findings emphasize the importance of fostering motor variability and promoting neuroplasticity through external focus strategies, including sensorimotor synchronization. While isochronous cues, an invariant stimulus, are commonly used, they do not reflect the natural fluctuations of healthy gait and may reduce its complexity. Fractal-based cues, in contrast, introduce structured variability resembling the natural dynamics of locomotion and have been shown to restore gait complexity in clinical populations. However, no study has yet explored their acute effects on gait variability and corticospinal function following ACL reconstruction (ACLR). This crossover randomized controlled trial aims to compare the acute effects of a single session of treadmill walking synchronized to either fractal or isochronous-based visual cues on gait variability and corticospinal measures in athletes with ACLR. The investigators hypothesize that fractal-based cueing will acutely restore gait variability and enhance corticospinal excitability, evidenced by increased corticospinal excitability and intracortical facilitation, and reduced short-interval intracortical inhibition, thus promoting adaptive neuroplasticity. Conversely, isochronous cueing is expected to maintain or decrease gait complexity without improving corticospinal measures. This study may provide insights that could be highly valuable as a way to promote neuroplasticity and optimize gait rehabilitation after ACLR, also allowing an objective quantification and aiming to restore variability to levels close to those observed in healthy individuals, thus contributing to reducing the re-injury rate.

Peri-implantitis is a growing public health problem that can lead to several complications and sequelae, with a serious impact on the health and quality of life of patients and a high cost for healthcare systems. Bacterial plaque that accumulates around dental implants leads to peri-implant tissue inflammation that ultimately can result in the loss of the implant, significant bone destruction and infection that can reach other regions. Successful implant decontamination is necessary to preserve the implant and several strategies have been suggested for this purpose, however, there is still no fully effective treatment modality and failures and recurrence are relatively frequent. To better understand this problem and develop more effective treatment strategies, investigators will first conduct an epidemiological study to understand the factors associated with the development of this pathology. Although there is data at an international level, the incidence of this problem in Portugal has not yet been properly studied. Later investigators will conduct a randomized clinical trial to evaluate the 6-week clinical outcomes of patients treated with a photodynamic therapy as an adjuvant versus the use of conventional titanium implant curettes for implant surface decontamination in the non-surgical treatment. Sixty patients/implants with peri-implantitis and within the established criteria, will undergo non-surgical treatment with one of the two protocols being studied. Various clinical and radiographic parameters will be evaluated, such as probing depth, insertion loss, recession, bleeding on probing, suppuration, peri-implant crevicular fluid volume, alveolar bone loss and peri-implantitis microbiome will be evaluated before surgery and 6 weeks after surgery.

The goal of this clinical trial is to investigate the effects of strength training with different focus of attention strategies on plantar flexor force and how this affects gait in apparently healthy older adults. The main questions it aims to answer are: * Is there an acute effect of focus of attention on non-linear force variability and the subjacent neurophysiological mechanisms in apparently healthy young and older adults? * Is there a training effect of focus of attention on non-linear force variability and does it transfer to non-linear gait variability as well as the respective subjacent neurophysiological mechanisms in apparently healthy older adults? Researchers will compare two different external focus strategies with an internal focus to see if non-linear variability increases and subjacent neurophysiological mechanisms are more automized with an external focus of attention compared to an internal focus. In the acute study young adults are assessed as the differences between focus conditions are thought to be in the same direction as for older adults but attenuated. Participants will carry out training and strength assessments of the calf muscles and walking on a treadmill.

Aging is a major risk factor for cardiovascular disease (CVD), contributing to progressive macrovascular and microvascular dysfunction. Macrovascular impairments, such as arterial stiffening and endothelial dysfunction, reduce nitric oxide (NO) bioavailability, leading to hypertension and impaired blood flow regulation. Microvascular dysfunction exacerbates cardiovascular decline by compromising capillary perfusion and tissue oxygenation, increasing susceptibility to ischemic events. Preserving vascular function is essential for maintaining cardiovascular health in aging populations. Low-intensity aerobic exercise (LIAE) improves cardiovascular health and mobility, particularly in populations unable to perform high-intensity exercise. However, LIAE alone often fails to induce significant vascular adaptations, such as improved arterial compliance or endothelial function, highlighting the need for optimized interventions. Blood Flow Restriction (BFR) enhances vascular adaptations during low-intensity exercise by inducing localized hypoxia, stimulating endothelial function and arterial remodeling. While BFR may transiently increase blood pressure and arterial stiffness, its vascular benefits resemble those of high-intensity exercise at lower workloads. However, research on BFR's acute vascular effects during aerobic exercise in older adults remains limited. Current studies have focused on perceptual and hemodynamic responses to LIAE+BFR but lack direct assessments of macrovascular (e.g., flow-mediated slowing) and microvascular function. Older adults may exhibit distinct vascular responses, yet data are scarce. This study examines acute vascular responses to LIAE+BFR and high-intensity interval exercise (HIIE) in young and older adults. Hypothesis: 1. BFR combined with LIAE will elicit greater acute microvascular and macrovascular responses in older adults than in younger adults. 2. These responses will be comparable to HIIE without BFR, suggesting BFR enhances LIAE's efficacy to high-intensity levels. 3. Any transient vascular dysfunction (e.g., increased arterial stiffness) will normalize within 30 minutes post-exercise, supporting safety in aging populations.

Photodynamic therapy (PDT) is an innovative technique that utilizes light-activated agents, known as photosensitizers, to produce reactive oxygen species capable of targeting and eliminating pathogens. This therapeutic approach has been explored in a variety of medical fields due to its versatility and minimal invasiveness. In the context of periodontal diseases, PDT has emerged as a promising adjunctive treatment in the non-surgical management of periodontitis. Periodontitis, a chronic inflammatory disease caused by the accumulation of pathogenic bacteria in the subgingival environment, is often treated with mechanical debridement, including scaling and root planing (SRP). However, these conventional methods may not always achieve complete bacterial eradication. PDT, when used in conjunction with SRP, has the potential to significantly enhance bacterial elimination. The use of photosensitizers, activated by specific wavelengths of light, leads to the generation of singlet oxygen, which can effectively kill a broad spectrum of periodontal pathogens, including those resistant to antibiotics. As an adjunctive therapy, PDT can improve the clinical outcomes of non-surgical periodontitis treatment by reducing bacterial load, promoting tissue healing, and potentially decreasing the need for more invasive procedures. The ability of PDT to target bacteria without harming surrounding tissues makes it an attractive option for patients who require a non-invasive treatment approach. In conclusion, photodynamic therapy is a valuable addition to periodontal treatment regimens, offering enhanced bacterial reduction and improved therapeutic outcomes in the management of periodontitis.

The goal of this clinical trial is to evaluate the influence of Facial Scan (FS) and cone beam computed tomography (CBCT) in the prosthodontic treatment planning in patients who require rehabilitation with a single crown. After collecting the patients, at the first appointment, data collection will be carried out, including: an intraoral scan (digital impressions), intraoral and extraoral photographs, CBCT, and facial scanning. At the following appointment, a mock-up will be performed. The purpose of the mock-up is to preview the expected smile outcome before beginning the oral rehabilitation treatment. After each mock-up, patients will be asked to complete a questionnaire designed to evaluate their self-perception of comfort and aesthetics. Additionally, after each mock-up, the clinician will assess occlusal contacts (the bite) and record the time required for adjustments to achieve a comfortable occlusion for the patient. The main questions it aims to answer are: * How does the patient perceive comfort and aesthetics during the rehabilitation process? * What is the influence of using a virtual articulator on diagnostic waxing accuracy? * How does integrating facial scanning (FS) and cone-beam computed tomography (CBCT) affect current digital workflows involving a virtual articulator? * What impact does the programming of the virtual articulator have on treatment planning outcomes?

This clinical trial aims to determine if Transcranial electrical stimulation by direct current (tDCS) and transauricular Vagus Nerve Stimulation (tVNS) treatments are effective in reducing stress symptoms, distress and improving sleep quality in adults. The main questions it aims to answer are: * Determine if tDCS effectively reduces the intensity of stress symptoms in adults. * Determine if tDCS is effective in reducing levels of distress in adults. * Determine if tDCS is effective in improving sleep quality. * Determine if tVNS is effective in reducing the intensity of stress symptoms in adults. * Determine if tVNS is effective in reducing levels of distress in adults. * Determine if tVNS is effective in improving sleep quality.

Aging leads to declines in functional capacity and effort tolerance. Muscle strength remains stable from ages 25 to 50 but declines significantly after age 60, affecting activities like stair climbing and walking, reducing autonomy and independence. While muscle atrophy is a significant factor, macrovascular endothelial dysfunction also impairs skeletal muscle performance in older adults. Nitric oxide (NO), produced by endothelial cells, regulates vascular homeostasis and contractile function. NO enhances muscle fiber shortening velocity, reduces twitch time-to-peak contraction, and increases the rate of force development. Aging-related endothelial dysfunction reduces NO availability, leading to reduced muscle mass and sarcopenia via decreased skeletal muscle perfusion. Increased arterial stiffness disrupts ventricular-vascular coupling, reducing cardiac output and contributing to age-related muscle weakness. Additionally, microvascular function decreases with age, contributing to altered physical work perception and reduced function. Low capillary density is linked to reduced walking speed in older adults and reduced walking time in peripheral arterial disease patients, supporting the microvasculature\'s role in functional performance. Reduced muscle mass also increases central hemodynamic load, impacting arterial stiffness and cardiac function. Resistance training (RT) is recommended to mitigate aging effects like loss of strength and muscle mass and reduce cardiovascular risk and all-cause mortality. Guidelines suggest 1-3 sets of 8-12 repetitions at 60-80% of the individual\'s repetition maximum (1RM), performed at least twice a week. However, older adults with osteoarthritis and cardiovascular conditions often cannot tolerate high mechanical stress and are prescribed lower intensity-resistance training (LIRT) at 40-50% of 1RM, typically yielding negligible muscle hypertrophy or strength gains. Blood flow restriction (BFR) training, which applies pressure bands to restrict blood flow during LIRT, increases muscle volume and strength. While BFR shows promise, it can cause acute increases in arterial stiffness and blood pressure in older adults, necessitating caution in its prescription. This study aims to compare macrovascular and microvascular function responses to acute resistance exercise with and without BFR in young and older adults. We hypothesize that older adults will show a more pronounced increase in macrovascular and microvascular dysfunction following resistance exercise compared to younger participants. In this parallel group randomized controlled trial, participants will be randomly assigned to either LIRT-BFR or high-intensity resistance training (HIRT). Each participant will attend three sessions: a familiarization session and two experimental sessions involving the randomized exercise conditions. Measurements of brachial blood pressure, heart rate, and macrovascular and microvascular function will be taken at rest and during recovery periods post-exercise.