Oxidative Stress in the Local and Systemic Events of Apical Periodontitis

Oxidative stress is involved in the pathogenesis of a variety of inflammatory disorders. Apical periodontitis (AP) usually results in the formation of an osteolytic apical lesion (AL) caused by the immune response to endodontic infection. Reactive oxygen species (ROS) produced by phagocytic cells in response to bacterial challenge represent an important host defense mechanism, but disturbed redox balance results in tissue injury. This mini review focuses on the role of oxidative stress in the local and associated systemic events in chronic apical periodontitis. During endodontic infection, ligation of Toll-like receptors (TLRs) on phagocytes' surface triggers activation, phagocytosis, synthesis of ROS, activation of humoral and cellular responses, and production of inflammatory mediators, such as, cytokines and matrix metalloproteinases (MMPs). The increment in ROS perturbs the normal redox balance and shifts cells into a state of oxidative stress. ROS induce molecular damage and disturbed redox signaling, that result in the loss of bone homeostasis, increased pro-inflammatory mediators, and MMP overexpression and activation, leading to apical tissue breakdown. On the other hand, oxidative stress has been strongly involved in the pathogenesis of atherosclerosis, where a chronic inflammatory process develops in the arterial wall. Chronic AP is associated with an increased risk of cardiovascular diseases (CVD) and especially atherogenesis. The potential mechanisms linking these diseases are also discussed.Peer reviewe

Development of a self-report questionnaire designed for population-based surveillance of gingivitis in adolescents: assessment of content validity and reliability

The major infectious diseases in Chile encompass the periodontal diseases, with a combined prevalence that rises up to 90% of the population. Thus, the population-based surveillance of periodontal diseases plays a central role for assessing their prevalence and for planning, implementing, and evaluating preventive and control programs. Self-report questionnaires have been proposed for the surveillance of periodontal diseases in adult populations world-wide. Objective This study aimed to develop and assess the content validity and reliability of a cognitively adapted self-report questionnaire designed for surveillance of gingivitis in adolescents. Material and Methods Ten predetermined self-report questions evaluating early signs and symptoms of gingivitis were preliminary assessed by a panel of clinical experts. Eight questions were selected and cognitively tested in 20 adolescents aged 12 to 18 years from Santiago de Chile. The questionnaire was then conducted and answered by 178 Chilean adolescents. Internal consistency was measured using the Cronbach’s alpha and temporal stability was calculated using the Kappa-index. Results A reliable final self-report questionnaire consisting of 5 questions was obtained, with a total Cronbach’s alpha of 0.73 and a Kappa-index ranging from 0.41 to 0.77 between the different questions. Conclusions The proposed questionnaire is reliable, with an acceptable internal consistency and a temporal stability from moderate to substantial, and it is promising for estimating the prevalence of gingivitis in adolescents

Osteoarthritis of the Temporomandibular Joint: Clinical and Imagenological Diagnosis, Pathogenic Role of the Immuno- Inflammatory Response, and Immunotherapeutic Strategies Based on T Regulatory Lymphocytes

Osteoarthritis is a degenerative disease affecting the TMJ. It is the most common TMJ disorder and shows a higher prevalence in women and older people. TMJ osteoarthritis (TMJ-OA) is characterized by variable degrees of inflammation, destruction of the articular cartilage, and sub-chondral bone resorption. In this context, diverse pro-inflammatory cytokines, chemokines, enzymes, and bone-resorptive associated factors have been considered as possible markers of active TMJ-OA. The molecular balance is determinant not only for initiation and progression, but also for the clinical expression of the disease. Recent advances in the biochemical analysis of synovial fluid from affected patients have provided new insights into the patho-physiology of the TMJ-OA; however, its molecular pathogenesis still remains unclear. Recently, a Th1 and Th17-dominated immune response has been associated with the inflammatory and destructive events characteristic of TMJ-OA and, in particular, the Th17 lymphocyte pathway has a pivotal role in the increased production of RANKL, which is involved in osteoclast activation and subsequent sub-chondral bone resorption. Understanding the TMJ physiology and pathogenesis of the TMJ-OA, together with the key molecular determinants of the TMJ tissue destruction, will enable the development of new chair-side point of care diagnostics and more conservative treatment modalities with minimal complications

Host response mechanisms in periodontal diseases

Periodontal diseases usually refer to common inflammatory disorders known as gingivitis and periodontitis, which are caused by a pathogenic microbiota in the subgingival biofilm, including Porphyromonas gingivalis, Aggregatibacter actinomycetemcomitans, Tannerella forsythia and Treponema denticola that trigger innate, inflammatory, and adaptive immune responses. These processes result in the destruction of the tissues surrounding and supporting the teeth, and eventually in tissue, bone and finally, tooth loss. The innate immune response constitutes a homeostatic system, which is the first line of defense, and is able to recognize invading microorganisms as non-self, triggering immune responses to eliminate them. In addition to the innate immunity, adaptive immunity cells and characteristic cytokines have been described as important players in the periodontal disease pathogenesis scenario, with a special attention to CD4+ T-cells (T-helper cells). Interestingly, the T cell-mediated adaptive immunity development is highly dependent on innate immunity-associated antigen presenting cells, which after antigen capture undergo into a maturation process and migrate towards the lymph nodes, where they produce distinct patterns of cytokines that will contribute to the subsequent polarization and activation of specific T CD4+ lymphocytes. Skeletal homeostasis depends on a dynamic balance between the activities of the bone-forming osteoblasts (OBLs) and bone-resorbing osteoclasts (OCLs). This balance is tightly controlled by various regulatory systems, such as the endocrine system, and is influenced by the immune system, an osteoimmunological regulation depending on lymphocyte- and macrophage-derived cytokines. All these cytokines and inflammatory mediators are capable of acting alone or in concert, to stimulate periodontal breakdown and collagen destruction via tissue-derived matrix metalloproteinases, a characterization of the progression of periodontitis as a stage that presents a significantly host immune and inflammatory response to the microbial challenge that determine of susceptibility to develop the destructive/progressive periodontitis under the influence of multiple behavioral, environmental and genetic factors

RvE1 Impacts the Gingival Inflammatory Infiltrate by Inhibiting the T Cell Response in Experimental Periodontitis

Periodontitis is a chronic inflammatory disease associated with the formation of dysbiotic plaque biofilms and characterized by the progressive destruction of the alveolar bone. The transition from health to disease is characterized by a shift in periodontal immune cell composition, from mostly innate (neutrophils) to adaptive (T lymphocytes) immune responses. Resolvin E1 (RvE1) is a specialized pro-resolution mediator (SPMs), produced in response to inflammation, to enhance its resolution. Previous studies have indicated the therapeutic potential of RvE1 in periodontal disease; however, the impact of RvE1 in the microbial-elicited osteoclastogenic immune response remains uncharacterized in vivo. In the present study, we studied the impact of RvE1 on the gingival inflammatory infiltrate formation during periodontitis in a mouse model. First, we characterized the temporal-dependent changes of the main immune cells infiltrating the gingiva by flow cytometry. Then, we evaluated the impact of early or delayed RvE1 administration on the gingival immune infiltration and cervical lymph nodes composition. We observed a consistent inhibitory outcome on T cells -particularly effector T cells- and a protective effect on regulatory T cells (Tregs). Our data further demonstrated the wide range of actions of RvE1, its preventive role in the establishment of the adaptive immune response during inflammation, and bone protective capacity.publishedVersio

The influence of flap design on patients’ experiencing pain, swelling, and trismus after mandibular third molar surgery: a scoping systematic review

Third molar removal surgery usually comes accompanied by postoperative discomfort, which could be influenced by the surgical approach chosen. This scoping systematic review aimed at compiling the available evidence focused on the influence of flap design, including envelope flap (EF), triangular flap (TF), and modified triangular flap (MTF), on postoperative pain, swelling, and trismus, as primary outcome measures, and any result mentioning healing promotion or delay, as secondary outcome measure, after mandibular third molar extraction surgery. An electronic search, complemented by a manual search, of articles published from 1999 to 2020 was conducted in the Medline (PubMed), EMBASE and Web of Science databases including human randomized controlled trials, prospective, and retrospective studies with at least 15 patients. The risk of bias of the included studies was assessed either with the Cochrane’s Risk of Bias tool or with the Newcastle-Ottawa scale. Every step of the review was performed independently and in duplicate. The initial electronic search recovered 2102 articles. After applying the inclusion criteria, 12 articles were included. For patient’s perceived postoperative pain, TF and MTF frequently reported better results than EF. For swelling, the literature is divided, despite a trend favoring EF. For trismus, data showed that its occurrence is mostly associated with the duration of the surgery rather than with the chosen flap. For healing, the limited data is inconclusive. Finally, randomized studies showed a high risk of bias, whereas nonrandomized studies were mostly of good quality and low risk of bias. Although there was no clear consensus regarding the influence of different flap designs for third mandibular molar extraction on postoperative clinical morbidities; the surgeon’s experience, estimated surgical difficulty, molar position and orientation, and surg ery duration should be considered when choosing among the different flap designs

Enfermedades crónicas

Adherencia al tratamiento farmacológico y relación con el control metabólico en pacientes con DM2Aluminio en pacientes con terapia de reemplazo renal crónico con hemodiálisis en Bogotá, ColombiaAmputación de extremidades inferiores: ¿están aumentando las tasas?Consumo de edulcorantes artificiales en jóvenes universitariosCómo crecen niños normales de 2 años que son sobrepeso a los 7 añosDiagnóstico con enfoque territorial de salud cardiovascular en la Región MetropolitanaEfecto a corto plazo de una intervención con ejercicio físico, en niños con sobrepesoEfectos de la cirugía bariátrica en pacientes con síndrome metabólico e IMC < 35 KG/M2Encuesta mundial de tabaquismo en estudiantes de profesiones de saludEnfermedades crónicas no transmisibles: Consecuencias sociales-sanitarias de comunidades rurales en ChileEpidemiología de las muertes hospitalarias por patologías relacionadas a muerte encefálica, Chile 2003-2007Estado nutricional y conductas alimentarias en adolescentes de 4º medio de la Región de CoquimboEstudio de calidad de vida en una muestra del plan piloto para hepatitis CEvaluación del proceso asistencial y de resultados de salud del GES de diabetes mellitus 2Factores de riesgo cardiovascular en población universitaria de la Facsal, universidad de TarapacáImplicancias psicosociales en la génesis, evolución y tratamiento de pacientes con hipertensión arterial esencialInfarto agudo al miocardio (IAM): Realidad en el Hospital de Puerto Natales, 2009-2010Introducción de nuevas TIC y mejoría de la asistencia a un programa de saludNiños obesos atendidos en el Cesfam de Puerto Natales y su entorno familiarPerfil de la mortalidad por cáncer de cuello uterino en Río de JaneiroPerfil del paciente primo-consultante del Programa de Salud Cardiovascular, Consultorio Cordillera Andina, Los AndesPrevalencia de automedicación en mujeres beneficiarias del Hospital Comunitario de Til-TiPrevalencia de caries en población preescolar y su relación con malnutrición por excesoPrevalencia de retinopatía diabética en comunas dependientes del Servicio de Salud Metropolitano Occidente (SSMOC)Problemas de adherencia farmacológica antihipertensiva en población mapuche: Un estudio cualitativoRol biológico de los antioxidantes innatos en pacientes portadores de VIH/SidaSobrepeso en empleados de un restaurante de una universidad pública del estado de São Paul