Monitoring of Immune Memory by Phenotypical Lymphocyte Subsets Identikit: An Observational Study in a Blood Donors' Cohort.

The cross-talk between the innate and adaptive immune response represents the first defense weapon against the threat of pathogens. Substantial evidence has shown a relationship between immune phenotype lymphocytes and COVID-19 disease severity and/or implication in susceptibility to SARS-CoV-2 infection. Recently, belonging to ABO blood groups has been investigated as a correlation factor to COVID-19 disease. This pilot study investigated lymphocyte typing in a cohort of blood donors to understand the underlying mechanism in SARS-CoV-2 infection linked to the blood group. The study cohort consisted of 20-64-year-old subjects, without comorbidities, from both sexes, who were COVID-19 vaccinated with previous or no infection history. Whole blood samples, collected at A.O.R.N. Sant'Anna and San Sebastiano Hospital (Campania Region), were processed by multiparametric cytofluorimetric assay, to characterize CD4+ helper and CD8+ cytotoxic T cell CD3+ subpopulations. The CD45RA, CCR7, CD27, CD28, CD57 and PD-1 markers were investigated to delineate the peripheral T-cell maturation stages. Differences were detected in ABO blood types in CD3+, CD4+ gated on CD3+, CD8+ and CD8+ gated on CD3+ percentage. These results contribute to identifying a memory cell "identikit" profile in COVID-19 disease, thus leading to a useful tool in precision medicine.

Comprehensive clinical and histological evaluation of bovine hydroxyapatite bone graft with polypropylene membrane versus leukocyte- and platelet-rich fibrin for alveolar preservation after tooth extraction.

BACKGROUND: Osseointegrated implant placement in the ideal prosthetic position necessitates a sufficient residual alveolar ridge. Tooth extraction and the subsequent healing process often lead to bony deformities, characterized by a reduction in alveolar ridge height and width, resulting in unfavorable ridge architecture for dental implant placement. Several materials, including allografts, alloplastics, xenografts, and autogenous bone, are commonly used to address these concerns. In this context, leucocyte- and platelet-rich fibrin (L-PRF) emerges as a promising solution. METHODS: This case report aims to compare the clinical and histological efficacy of bovine hydroxyapatite bone graft covered with polypropylene membrane (BHAG-PM) and leucocyte- and platelet-rich fibrin (L-PRF) in preserving dental alveoli following tooth extraction. Extraction, graft placement in the alveoli, and the anterior border between extracted elements were performed for both treatment groups. RESULTS: Up to 24 months of follow-up revealed satisfactory and comparable clinical and histological outcomes. These results suggest that both BHAG-PM and L-PRF effectively promote alveolar preservation, paving the way for ideal implant placement. CONCLUSIONS: In general, bone-substitute materials are effective in reducing alveolar changes after tooth extraction. Xenograft materials should be considered as among the best of the available grafting materials for alveolar preservation after tooth extraction. Both techniques effectively preserve the alveolar bone and facilitate the placement of osseointegrated implants in ideal positions, paving the way for successful oral rehabilitation.

The literature discusses oral manifestations caused by sexually transmitted viruses: a narrative review.

This review provides practical recommendations for dental practitioners in dealing with oral lesions associated with sexually transmitted diseases (STDs), offering clinically relevant insights to increase the awareness of these diseases in the mainstream of everyday practice. STDs are acquired through unprotected vaginal, anal or oral sex and are caused by more than 30 different types of bacteria, viruses and protozoa. Saliva, precum, semen, vaginal secretions and menstrual blood could be likely vehicles of infections and defensive barriers to infection by pathogenic microbes could be represented via intact mucosal membrane, the diluent function of saliva, and the antimicrobial action of salivary enzymes that collectively contribute to oral health and protection. STD, can directly and indirectly affect mucous membranes, manifesting with characteristic diagnostic signs and lesions. Given their potential oral manifestations, dental professionals need a comprehensive understanding of STD. The findings of this review lay a foundation for comprehending several STDs, emphasizing the importance of physicians as well dental practitioners being open to discussing sexuality issues with patients and providing appropriate therapeutic interventions.

The "Magnificent Seven" in Oral and Systemic Health against COVID-19.

The COVID-19 pandemic impacted all areas of daily life, including medical care. Unfortunately, to date, no specific treatments have been found for the cure of this disease, and therefore, it is advisable to implement all possible strategies to prevent infection. In this context, it is important to better define the role of all behaviors, in particular nutrition, in order to establish whether these can both prevent infection and improve the outcome of the disease in patients with COVID-19. There is sufficient evidence to demonstrate that immune response can be weakened by inadequate nutrition. Nutrition management and treatment are very important to enhance the immune response of an infected person against RNA viral infection. A complete nutritional assessment should include anthropometric, dietary, and laboratorial assessment, as well as a multidisciplinary discussion about the patient's clinical condition. In this way, it is possible to establish an individualized nutritional approach to contribute to improving clinical and nutritional prognoses. From this point of view, diet, through intake of vitamins and trace elements and maintaining adequate functioning of the intestinal barrier, can reduce the severity of the COVID-19 infection. In this study, we provide an overview of the effects of diet on COVID-19 infection in non-cancer patients. This notion needs to be further evaluated, and thus, identification, characterization, and targeting of the right nutrition principles related to the management of patients with COVID-19 are likely to improve outcomes and may prevent the infection or lead to a cure.

Dietary Polyphenols against Oxidative Stress in Head and Neck Cancer: What's New, What's Next.

Head and neck cancers (HNC) are a worldwide health problem, accounting for over 5% of all types of cancers. Their varied nature makes it sometimes difficult to find clear explanations for the molecular mechanisms that underline their onset and development. While chemio- and radiotherapy are clearly not to be dismissed, we cannot undervalue the effect that polyphenols - especially dietary polyphenols - can have in helping us to cope with this medical emergency. By influencing several different proteins involved in numerous different metabolic pathways, polyphenols can have a broad spectrum of biological action and can hopefully act synergistically to tackle down head and neck cancer. Moreover, being natural molecules, polyphenols does not present any side effects and can even enhance drugs efficacy, making our clinical therapy against head and neck cancer more and more effective. Certainly, oxidative stress plays an important role, altering several molecular pathways, lowering the body's defenses, and ultimately helping to create a microenvironment conducive to the appearance and development of the tumor. In this regard, the regular and constant intake of foods rich in polyphenols can help counteract the onset of oxidative stress, improving the health of the general population. In this review, we highlight the role of polyphenols in managing oxidative stress, with such positive effects that they can be considered new tools to use in our anti-head and neck cancer strategy.

Optimization of Cobalt-Chromium (Co-Cr) Scaffolds for Bone Tissue Engineering in Endocrine, Metabolic and Immune Disorders.

Approximately 50% of the adult global population is projected to suffer from some form of metabolic disease by 2050, including metabolic syndrome and diabetes mellitus. At the same time, this trend indicates a potential increase in the number of patients who will be in need of implant-supported reconstructions of specific bone regions subjected to inflammatory states. Moreover, physiological conditions associated with dysmetabolic subjects have been suggested to contribute to the severity of bone loss after bone implant insertion. However, there is a perspective evidence strengthening the hypothesis that custom-fabricated bioengineered scaffolds may produce favorable bone healing effects in case of altered endocrine or metabolic conditions. This perspective review aims to share a comprehensive knowledge of the mechanisms implicated in bone resorption and remodelling processes, which have driven researchers to develop metallic implants as the cobalt-chromium (Co-Cr) bioscaffolds, presenting optimized geometries that interact in an effective way with the osteogenetic precursor cells, especially in the cases of perturbed endocrine or metabolic conditions.

Extracellular Vesicles as a Translational Approach for the Treatment of COVID-19 Disease: An Updated Overview.

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) caused a global pandemic in the years 2020-2022. With a high prevalence, an easy route of transmission, and a long incubation time, SARS-CoV-2 spread quickly and affected public health and socioeconomic conditions. Several points need to be elucidated about its mechanisms of infection, in particular, its capability to evade the immune system and escape from neutralizing antibodies. Extracellular vesicles (EVs) are phospholipid bilayer-delimited particles that are involved in cell-to-cell communication; they contain biological information such as miRNAs, proteins, nucleic acids, and viral components. Abundantly released from biological fluids, their dimensions are highly variable, which are used to divide them into exosomes (40 to 150 nm), microvesicles (40 to 10,000 nm), and apoptotic bodies (100-5000 nm). EVs are involved in many physiological and pathological processes. In this article, we report the latest evidence about EVs' roles in viral infections, focusing on the dual role of exosomes in promoting and inhibiting SARS-CoV-2 infection. The involvement of mesenchymal stromal/stem cells (MSCs) and MSC-derived EVs in COVID-19 treatment, such as the use of translational exosomes as a diagnostical/therapeutic approach, is also investigated. These elucidations could be useful to better direct the discovery of future diagnostical tools and new exosome-derived COVID-19 biomarkers, which can help achieve optimal therapeutic interventions and implement future vaccine strategies.

Radiographic marginal bone level evaluation around two different tissue-level implant systems: a one-year prospective study.

BACKGROUND: Marginal bone loss, is a frequently reported variable in the evaluation of dental implants. The primary objective of this study was to evaluate radiographic marginal bone level changes around the two different tissue-level implant systems placed adjacently in the posterior maxilla or mandible. The influence of implant macro-geometry and vertical soft tissue thickness on marginal bone loss were also evaluated. METHODS: Seven patients were included in the study and a total of 18 implants were analyzed. Each patient received two different implants placed adjacently in the maxilla or the mandible. The implants used in our study were either Straumann® SP cylindrical implants or JD Octa® tapered implants. During the surgery, vertical soft-tissue thickness was measured with a periodontal probe placed on the top of the bony crest and in the center of the future implant site. Healing abutments were then seated. Three months following implant placement, impressions were taken, and screw-retained metal ceramic prostheses were delivered. Standardized intraoral radiographs were taken immediately after implant placement and one year following implant loading in order to assess marginal bone level changes. RESULTS: Results showed a mean marginal bone loss of 0.55±0.5 mm for Straumann® SP implants and 0.39±0.49 mm for JD Octa® implants after one year of loading and the difference was not statistically significant between the two systems. A statistically significant correlation was found between soft tissue thickness and marginal bone loss; in sites with thin mucosal tissues (≤2 mm), there was significantly greater bone loss compared to sites with thick, soft tissues (> 2 mm) in both implants. CONCLUSIONS: Radiographic marginal bone loss was not statistically different between the two implant systems at the one-year examination period. Moreover, vertical soft tissue thickness influenced marginal bone loss regardless of the implant system used.

Exploring the Association of Burning Mouth Syndrome with Depressive and Anxiety Disorders in Middle-Aged and Older Adults: A Systematic Review.

BACKGROUND: Burning Mouth Syndrome (BMS) is an idiopathic condition mainly affecting middle-aged and older individuals with hormonal disturbances or psychiatric disorders and is characterized by chronic pain. The etiopathogenesis of this multifactorial syndrome is largely unknown. The objective of the present systematic review was therefore to evaluate the relationship of BMS with depressive and anxiety disorders in middle-aged and older individuals. METHODS: We selected studies evaluating BMS and depressive and anxiety disorders assessed with validated tools, published from their inception up to April 2023, using PubMed, MEDLINE, EMBASE, Scopus, Ovid, and Google Scholar databases and adhering to the PRISMA 2020 guidelines/PRISMA 2020 27-item checklist. This study is registered on PROSPERO (CRD42023409595). The National Institutes of Health Quality Assessment Toolkits for Observational Cohort and Cross-Sectional Studies were used to examine the risk of bias. RESULTS: Two independent investigators rated 4322 records against the primary endpoint and found 7 records meeting the eligibility requirements. Anxiety disorders were found to be the most common psychiatric disorders related to BMS (63.7%), followed by depressive disorders (36.3%). We found a moderate association of BMS with anxiety disorders, with multiple studies included (n = 7). Moreover, we found a low association of BMS with depressive disorders (included studies, n = 4). The role of pain appeared to be controversial in explaining these associations. CONCLUSIONS: In middle-aged and older subjects, anxiety and depressive disorders may be potentially related to the development of BMS. Furthermore, also in these age groups, females showed higher risk of developing BMS than males, even when taking into account multimorbidity such as sleep disorders, personality traits, and biopsychosocial changes as suggested by study-specific findings.

The ancient roots of dentistry in the Mediterranean civilizations: between Etruscan and Greek traditions up to the time of imperial Rome.

Etruscans, people living in Etruria (Umbria and Tuscany, Italy), were the first to make dentures and false teeth, from 700 BCE onwards. The aim of this study was to investigate, through archaeological and anthropological records, the Etruscans ability in dental practice to understand better Greek's influence on their medical knowledge and, subsequently, the transmission of their medical expertise to Romans. We extensively searched literature to find out references in previous studies on Etruscan medical and dental practice by using keywords such as "Etruscan medicine" and "Etruscan dentistry." We selected various historical papers, from the ancient age texts of 5th century to 2020, which best focused on the review's purpose. Etruscan civilization was influenced by Greek's culture throughout Italian colonies and later "merge" into Greek-Roman culture. Their medical practice based on a mixture of mythology, religion, and technical abilities, especially regarding metalworking. Archaeological remains show a great competence in creating dental prosthesis and in treatment of oral diseases. The results of this paper provide an evident contribution to the knowledge of Etruscan culture, still largely unknown by an anthropological point of view, and their strong relationship with the Greeks colonies, in a profitable cultural exchange.

About Functional Foods: The Probiotics and Prebiotics State of Art.

Poor diet, obesity and a sedentary lifestyle have a significant impact on natural microbiota disorders; specifically, the intestinal one. This in turn can lead to a multitude of organ dysfunctions. The gut microbiota contains more than 500 species of bacteria and constitutes 95% of the total number of cells in the human body, thus contributing significantly to the host's resistance to infectious diseases. Nowadays, consumers have turned to purchased foods, especially those containing probiotic bacteria or prebiotics, that constitute some of the functional food market, which is constantly expanding. Indeed, there are many products available that incorporate probiotics, such as yogurt, cheese, juices, jams, cookies, salami sausages, mayonnaise, nutritional supplements, etc. The probiotics are microorganisms that, when taken in sufficient amounts, contribute positively to the health of the host and are the focus of interest for both scientific studies and commercial companies. Thus, in the last decade, the introduction of DNA sequencing technologies with subsequent bioinformatics processing contributes to the in-depth characterization of the vast biodiversity of the gut microbiota, their composition, their connection with the physiological function-known as homeostasis-of the human organism, and their involvement in several diseases. Therefore, in this study, we highlighted the extensive investigation of current scientific research for the association of those types of functional foods containing probiotics and prebiotics in the diet and the composition of the intestinal microbiota. As a result, this study can form the foundation for a new research path based on reliable data from the literature, acting a guide in the continuous effort to monitor the rapid developments in this field.

Ceramic Materials for Biomedical Applications: An Overview on Properties and Fabrication Processes.

A growing interest in creating advanced biomaterials with specific physical and chemical properties is currently being observed. These high-standard materials must be capable to integrate into biological environments such as the oral cavity or other anatomical regions in the human body. Given these requirements, ceramic biomaterials offer a feasible solution in terms of mechanical strength, biological functionality, and biocompatibility. In this review, the fundamental physical, chemical, and mechanical properties of the main ceramic biomaterials and ceramic nanocomposites are drawn, along with some primary related applications in biomedical fields, such as orthopedics, dentistry, and regenerative medicine. Furthermore, an in-depth focus on bone-tissue engineering and biomimetic ceramic scaffold design and fabrication is presented.

Is the Non-Coding RNA miR-195 a Biodynamic Marker in the Pathogenesis of Head and Neck Squamous Cell Carcinoma? A Prognostic Meta-Analysis.

Head and neck squamous cell carcinoma (HNSCC) represents a heterogeneous group of neoplasms whose histological derivation comes from the mucous membranes lining the epithelium: the oral cavity, the larynx, the hypopharynx, the nasopharynx, and the oropharynx. The etiopathogenetic mechanisms involving tumor genesis including the alteration of cell proliferation, apoptosis, invasion, migration, and death may involve alterations in the expression of microRNA (miR). To date there have been no systematic reviews with meta-analysis conducted specifically on the role of miR-195 in HNSCC; therefore, our hypothesis was to evaluate if the aberrant expression of miR-195 in HNSCC tissues may represent a prognostic biomarker of survival through the hazard ratio (HR) and relative risk (RR) analysis. The systematic review was designed according to the PRISMA indications; in total, three electronic databases were consulted (PubMed, Scopus, Cochrane Central Trial) including Google Scholar and the gray literature, and a combination of keywords was used such as miR-195 AND HNSCC, microRNA AND HNSCC and miR-195. The meta-analysis and trial sequential analysis were performed using RevMan 5.41 software and TSA software (Cochrane Collaboration, Copenhagen, Denmark). This search identified 1592 articles and, at the end of the selection process, three articles were included. The results of the meta-analysis reported an aggregated risk ratio for overall survival (OS) between the expression of miR-195 at the highest and lowest of 0.36 and 6, respectively, 95% CI: [0.25, 0.51]. Heterogeneity was evaluated through Chi2 = 0.05 df = 2 (p = 0.98) and the Higgins index I2 = 0%. The test for the overall effect was Z = 5.77 (p < 0.00001). The forest plot was in favor of higher OS in patients with high miR-195 expression.

Comparative study of the anaesthetic efficacy of 4% articaine versus 2% mepivacaine in mandibular third molar germectomy using different anaesthetic techniques: a split-mouth clinical trial.

BACKGROUND: Currently, one of the most discouraging aspects for many patients undergoing dental procedures is the administration of local anaesthesia. Therefore, there is a constant search for new techniques to avoid the invasive and painful nature of the injection. This study aimed to compare the clinical efficacy of local anaesthetics with articaine 4% or mepivacaine 2% (both with epinephrine 1:100.000), using different anaesthetic techniques to perform germectomy of lower third molars and to assess patients' feelings and pain during surgery. METHODS: Totally 50 patients (ranged 11-16 years) who required germectomy of mandibular third molars were recruited. Each patient received local anaesthesia on one side with articaine inoculated with plexus technique while on the other side with mepivacaine using inferior alveolar nerve block technique. The patients' evaluation was performed on pre and intraoperative tactile-pressure feelings and intraoperative pain with four levels on the Visual Analogue Scale (VAS). RESULTS: Surgical operations lasted less with more efficient analgesia when articaine was used. The additional intraosseous injection was required mainly in the mepivacaine group intraoperatively. A few patients had tactile-pressure feelings while intraoperative pain sensation was absent in 90% of cases with articaine. Significant differences were found in the cases who reported "absent" and "moderate" VAS values, favoring the use of articaine. CONCLUSIONS: Articaine injected with a plexus anaesthetic technique seems to be more clinically manageable than mepivacaine for the mandibular third molar germectomy. The discomfort of tactile-pressure feelings and pain experienced was lower using articaine anaesthetic technique used.

Correlation between Diabetes Mellitus and Peri-implantitis: A Systematic Review.

BACKGROUND: Osseo-integrated implants provide effective treatment results for edentulous patients. However, despite the high success and survival rates of dental implants, several factors, such as poor oral hygiene and a history of periodontal disease, and systemic diseases, such as diabetes mellitus, could influence the outcome of the treatment. In fact, poor glycemic control can affect the healing process. Diabetes mellitus is considered a relative contraindication for dental implant therapy due to the fact that the success rates of the implants seem to be lower in diabetic patients, even if there is no total agreement among the results reported in the literature. The analysis of peri-implant inflammation indices, bone loss around the implant and glycemic index can provide us with useful information on the relationship between glycaemia in diabetic patients and the course of peri-implantitis, as well as implant success in the short term. OBJECTIVE: The purpose of this review is to establish how peri-implant inflammation parameters vary in diabetic versus non-diabetic patients. METHODS: This review was conducted on the basis of PRISMA. The search was conducted by three independent reviewers searching for keywords in three databases: PubMed, Scopus, Web Of Sciences (WOS), and the Cochrane Central Register of Controlled Trial. RESULTS: A total of 1159 records were identified, and 11 articles were included in the qualitative analysis. CONCLUSION: The analysis of the extracted data from the included studies suggests that some periimplant inflammation indices, such as bleeding on probing and bone loss around the implant, appear to be increased in diabetic patients with glycometabolic decompensation, compared with control not affected by diabetes mellitus.

Natural Bioactive Compounds against Oxidative Stress: Dietary Polyphenols Strike Back.

Oxidative stress is a major cellular and metabolic burden that can really alter cell life and become the base for disease onset and development. Many widespread pathologies can develop from an unresolved oxidative stress situation; thus, addressing this state is paramount for human health. Our antioxidant enzymes sometimes are not just enough. Fortifying our defense and the antioxidant and anti-inflammatory system can make a difference in our health: if this is attainable with our dietary habits, it could be a dream come true. Polyphenols are a fantastic tool indeed in the fight against oxidative stress: they are easy to obtain, with little cost, no side effects, and have a multitude of metabolic actions. This perspective review would shed light on polyphenol's metabolic and molecular action regarding oxidative stress to help preserve our health.

Temporomandibular Disorders as a Risk Factor for Suicidal Behavior: A Systematic Review.

BACKGROUND: Temporomandibular disorders (TMD) are a group of common musculoskeletal dysfunctions that affect the temporomandibular joint or masticatory muscles and related structures or are expressed as a clinical combination of these two factors. The etiology of TMD is multifactorial and features related to anxiety, depression and mental disorders can contribute to the predisposition, onset and progression of TMD. The ability to adapt and develop coping attitudes was reduced in patients presenting with chronic pain, while suicidal behavior (suicidal ideation, suicide attempts, and suicide completion) was increased. The objective of this review was therefore to investigate suicidal behavior in relation to TMD. METHODS: The review was performed according to the PRISMA 2020 guidelines. Six databases (PubMed, MEDLINE, EMBASE, Scopus, Ovid, and Google Scholar) were consulted through the use of keywords related to the review topic. The study is registered on PROSPERO (CRD42022320828). RESULTS: The preliminary systematic search of the literature yielded 267 records. Excluding duplicates, 15 were considered potentially relevant and kept for title and abstract analysis. Only six articles were considered admissible reporting a single exposure factor, TMD and a single outcome, suicidal behavior, although these were evaluated through different assessment tools. We found a low association of TMD with suicidal behavior in observational studies, with estimates partly provided [prevalence ratio (PR) from 1.26 to 1.35, 95% confidence intervals (CI) from 1.15 to 1.19 (lower) and from 1.37 to 1.54 (higher); and odds ratios (OR) from 1.54 to 2.56, 95% CI from 1.014 to 1.157 (lower) and 2.051 to 6.484 (higher)], a relevant sample size (n = 44,645), but a few studies included (n = 6). CONCLUSIONS: The results of the included studies showed that the prevalence data of suicidal behavior were more present in young adults with TMD, with a controversial association with gender. Suicidal behavior was also correlated and aggravated by the intensity of pain.

Effects of Vitamin D on the Renin-Angiotensin System and Acute Childhood Pneumonia.

Vitamin D promotes kidney calcium reabsorption and regulates calcium and phosphate metabolism, as well as the intestinal absorption of calcium and phosphorus and bone mineralization events. Vitamin D is also known for its immunomodulatory properties. It has been shown in the literature that the active form of vitamin D, 1,25-dihydroxyvitamin D, performs multiple functions in the adaptive and innate immune system, as well as acting on the endothelial membrane. Recent evidence shows that vitamin D is a negative endocrine modulator of the renin-angiotensin system (RAS), with protection from diseases leading to lung damage, such as pneumonia caused by various pathogens. Vitamin D support associated with the use of antibiotics could be crucial to counteract these infectious diseases.

Update on COVID-19 and Effectiveness of a Vaccination Campaign in a Global Context.

The COVID-19 pandemic caused by SARS-CoV-2 remains a significant issue for global health, the economy, and society. When SARS-CoV-2 began to spread, the most recent serious infectious disease of this century around the world, with its high morbidity and mortality rates, it is understandable why such infections have generally been spread in the past, mainly from international travel movements. This perspective review aimed to provide an update for clinicians on the recent developments related to the microbiological perspectives in pandemics, diagnostics, prevention (such as the spread of a virus), vaccination campaigns, treatment options, and health consequences for COVID-19 based on the current literature. In this way, the authors attempt to raise awareness on the transversal nature of these challenges by identifying the main risk/vulnerability factors that the scientific community must face including our current knowledge on the virus capacity of the mechanism of entry into the cells, the current classifications of viral variants, the knowledge of the mathematical model on the spread of viruses (the possible routes of transmission), and the effectiveness of vaccination campaigns in a global context of pandemic, particularly from COVID-19, with a look at new or future vaccines.

Does miR-197 Represent a Valid Prognostic Biomarker in Head and Neck Squamous Cell Carcinoma (HNSCC)? A Systematic Review and Trial Sequential Analysis.

(1) Background: Between tumors of the head and neck region, the squamous cell variant (HNSCC) is the most common and represents one of the main neoplasms affecting humans. At the base of carcinogenesis processes, there are genetic alterations whose regulation can be influenced by changes in the expression of microRNA (miR). Consequently, despite recent studies indicating miR-197 as a potential prognostic biomarker of survival for many varieties of cancer, there are currently no systematic reviews and trial sequential/bioinformatics/meta-analysis regarding the role of miR-197 in HNSCC. Our hypothesis was that with the existing literature, it is possible to clarify whether the different expressions of miR-197 in neoplastic tissues can represent a prognostic biomarker of survival in head and neck tumors. (2) Methods: The systematic review was reported following the indications of PRISMA and by consulting six electronic databases (including one register). Moreover, this review was carried out using the Kaplan-Meier plotter database portal, and hazard ratio (HR) data were extracted. Finally, a trial sequential analysis (TSA) was conducted to test the robustness of the proposed meta-analysis. (3) Results: This search identified 1119 articles and outcomes of the meta-analysis, reporting an aggregate HR for overall survival (OS) between the highest and lowest miR-197 expression of 1.01, 95% CI: [1.00, 1.02]. (4) Conclusions: We can state that, from the literature data included in the present meta-analysis, and from the TSA and bioinformatics analysis data, miR-197 does not currently represent a valid prognostic biomarker for HNSCC, although the data provided by the Kaplan-Meier plotter suggest that miR-197 can serve as a putative biomarker in short-term (5 years) survival.