Imunoexpressão de fatores reguladores da osteoclastogênese na doença periodontal em humanos e sua relação com os parâmetros clínicos

Periodontal disease is an infection initiated by oral periodontal pathogens that trigger an immune response culminating in tissue destruction. This destruction is mediated by the host by inducing the production and activation of lytic enzymes, cytokines and the stimulation of osteoclastogenesis. The aim of this study was to compare the immunohistochemical expression of factors involved in bone resorption, RANKL (Ligand Receptor Activator of Nuclear Factor kappa B), OPG (Osteoprotegerin) and TNF-α (tumor necrosis factor alpha) between the gingival healthy, gingivitis and chronic periodontitis and correlate them with clinical parameters. The sample consisted of 83 cases and 12 clinically healthy gums, 42 gingivitis and 29 periodontitis, from 74 adolescent and adult patients with a mean age of 35 years, without systemic changes and non-smokers, predominantly female and race brown. There was no statistically significant difference for the expression of anti-RANKL (p = 0.581) and RANKL / OPG ratio (p = 0.334) when comparing the three conditions, but the anti-OPG and anti-TNF-α showed statistically significant between the types of injury (p = 0.001 and p <0.001, respectively), showing greatest expression in periodontitis. In cases of periodontitis, the variable clinical attachment loss (PIC) was statistically significant and positive correlation, respectively, with immunostaining of anti-RANKL (p = 0.002, p = 0.001 and r = 0.642), anti-OPG (p = 0.018, p = 0.014 and r = 0.451), anti-TNF-α (p = 0.032, p = 0.014 and r = 0.453) and the percentage ratio of RANKL / OPG (p = 0.018, p = 0.002 and r = 0.544). The tooth mobility (MB) showed a statistically significant difference only with immunohistochemical anti-RANKL (p = 0.026), and probing depth (PD) was positively correlated with anti-RANKL (p = 0.028 and r = 0.409), both in cases of periodontitis. Only in cases of gingivitis TNF-α was positively correlated with RANKL (p = 0.012 and r = 0.384) and the RANKL / OPG ratio (p = 0.027 and r = 0.341). Given these results, we conclude that the greatest expression of TNF-α in periodontitis demonstrates a relationship with the progression and severity of periodontal disease and the correlation between all antibodies and clinical attachment loss demonstrates their involvement in periodontal bone resorption

Perfil periodontal de pacientes portadores de alterações endócrino-metabólicas

Objective- Convinced that periodontium, many times, can show alterations in human health, the aim of these studies was to investigate the periodontal situation in patients with endocrine-metabolic disorders such as, Berardinelli-Seip Syndrome, hyperthyroidism, hypothyroidism and acromegaly. Methods- Eight patients with Berardinelli-Seip Syndrome, 16 acromegalics, 30 hypothyroids, 30 hyperthyroids, and a control group with 35 patients were evaluated. Clinical attachment loss, probing depth, gingival bleeding index, gingival overgrowth and Index of Decayed, Missing and Filled Teeth were measured in each patient. All ethical aspects were rigidly observed, being the study conducted after its approval by the University of Fortaleza Research Ethics Committee. Results- The presence of periodontitis was marked in hyperthyroids and in patients with Berardinelli-Seip Syndrome. Hypothyroids showed not much presence of periodontitis, while all acromegalics presented absence of periodontitis. Conclusions- The protective effect of periodontitis in acromegalic patients is a new finding, whose mechanisms are not yet clear, but may be related to the anabolic effects of growth hormone. The presence of periodontitis in Berardinelli-Seip Syndrome may occur due the early onset of diabetes. In hyperthyroids, the high prevalence of periodontitis could be linked to thyroid hormones effects on bone, explaining also the minor prevalence in hypothyroids

Adesão de células mesenquimais da medula óssea de camundongos e do ligamento periodontal de ratos a diferentes superfícies de titânio: estudo comparativo in vitro

The present experiment used cell culture to analyze the adhesion capacity of mouse mesenchymal bone marrow cells and rat periodontal ligament to different titanium surfaces. Grade II ASTM F86 titanium discs 15mm in diameter and 1.5mm thick were used and received 2 distinct surface treatments (polished and cathodic cage plasma nitriding). The cells were isolated from the mouse bone marrow and rat periodontal ligament and cultured in α-MEM basic culture medium containing antibiotics and supplemented with 10% FBS and 5% CO2, for 72 hours at 37ºC in a humidified atmosphere. Subculture cells were cultured in a 24-well plate with a density of 1 x 104 cells per well. The titanium discs were distributed in accordance with the groups, including positive controls without titanium discs. After a 24-hour culture, the cells were counted in a Neubauer chamber. The results show that both the mouse mesenchymal bone marrow cells and rat periodontal ligament cells had better adhesion to the control surface. The number of bone marrow cells adhered to the polished Ti surface was not statistically significant when compared to the same type of cell adhered to the Ti surface treated by cathodic cage plasma nitriding. However a significant difference was found between the control and polished Ti groups. In relation to periodontal ligament cell adhesion, a significant difference was only found between the control and plasma-treated Ti surfaces. When comparing equal surfaces with different cells, no statistically significant difference was observed. We can therefore conclude that titanium is a good material for mesenchymal cell adhesion and that different material surface treatments can influence this process

Resposta celular Th1 /Th2 na doença periodontal experimental, em ratos: um estudo imuno-histoquímico

Host response plays a major role in the pathogenesis of periodontal disease. Mediators such as inflammatory cytokines which are secreted during the immune response to bacterial challenges have ambiguous functions that may or may not lead to protection of the attacked tissue. In this context, experimental evidence suggests that T-helper 1 (Th-1) and T-helper 2 (Th-2) mediated responses are potentially important during the disease process. The aims of this study therefore were to further clarify the role played by Th2 cells during different time points of the active phase of periodontal disease, as well as, to investigate whether there was any evidence of a Th1 response in the periodontal disease microenvironment. Experimental periodontitis was induced in 30 Wistar male rats by placing cotton ligatures around the mandibular first molars. The rats were then randomly divided into two groups. Group1 (G1=15) and Group 2 (G2=15). In G1 the ligatures were maintained for 2 days, whereas in G2 the ligatures were left for 15 days, a time point that corresponds to the advanced stage of periodontal disease The contra-lateral teeth served as controls (no ligatures). Immunohistochemical investigation for the presence in gingival tissue of Th2 specific transcription factor (GATA3) and the subunit of the IFN-γ receptor was carried out after the disease induction period. Light microscopy analysis revealed a decrease in the expression of GATA-3 as bone loss progressed. On the other hand, although IFN-γ R1 was detected at an early stage of the active phase of disease its expression remained unaltered during the remaining period of the study. These results indicate that the Th2 response have a protective role during the pathogenesis of periodontal disease and that the progression of the periodontal disease is related with the unbalance of the responses Th1/Th2

Análise imuno-histoquímica das metaloproteinases da matriz ( MMP-1,MMP-2 e MMP-9) na doença periodontal

The tissular destruction found in periodontal diseases is caused mainly by components of the host that have its production stimulated by the products of the microorganisms present on the plaque. Matrix Metalloproteinases (MMPs), a class of enzymes involved both in physiologic and pathologic extracellular matrix degradation are considered the main responsible for the characteristic tissular loss in periodontal disease, and the understanding of how this happens can have a series of beneficial implications for prevention, diagnosis and treatment of this illness. The aim of this work was to study the immunohistochemical expression of MMP-1, MMP-2, and MMP-9 in fragments of gingival biopsies with clinical diagnose of periodontal disease. MMP-1 has expressed significantly more than the others MMPs in gingivitis both in the epithelium (p=0,0008) and connective tissue (p=0,0049). In periodontitis, both MMP-1 and MMP-9 has expressed significantly more than MMP-2 in the epithelium (p<0,0001) and in the connective tissue (p=0,0002). MMP-1 and MMP-9 presented more expression in periodontitis than in gingivitis but MMP-1 only in the connective tissue (p=0,03) and MMP-9 in the epithelium (p=0,003) and in the connective tissue (p=0,04). In conclusion, these results indicate that the MMP-1 presents high expression in every stages of the periodontal diseases, and increases its expression in the connective tissue when the gingivitis evolves to periodontitis. Therefore, it may have an important role in connective tissue degradation and bone loss observed in disease, since early, in gingivitis, until late stages, in periodontitis, of the periodontal disease. MMP-9 has expressed more in periodontitis than in gingivitis, both in epithelium and in connective tissue. It means that this enzyme may have some importance in the progression of gingivitis to periodontitis by acting in bone resorption observed in this desease

Efeitos da azilsartana sobre a doença periodontal em um modelo experimental com ratos wistar

Periodontal diseases, highly prevalent disease in worldwide population, manifest primarily in two distinct entities: plaque-induced gingivitis and periodontitis. Periodontitis is a chronic inflammatory disease characterized of different levels of collagen, cementum, and alveolar bone destruction. Recent experimental studies demonstrated anti-inflammatory and antirreabsortive effect of antihypertensive agents of the angiotensin II receptor blockers class on periodontal disease. The aim of this study was to evaluate the effects of azilsartan (AZT), a potent inhibitor of the angiotensin II receptor which has minimal adverse effects on bone loss, inflammation, and the expression of matrix metallo proteinases (MMPs), receptor activator of nuclear factor kB ligand (RANKL), receptor activator of nuclear factor kB (RANK), osteoprotegerin (OPG), cyclooxygenase-2 (COX-2), and cathepsin K in periodontal tissue in a rat model of ligature-induced periodontitis. Male Wistar albino rats were randomly divided into 5 groups of 20 rats each: (1) nonligated, water; (2) ligated, water; (3) ligated, 1 mg/kg AZT; (4) ligated, 5 mg/kg AZT; and (5) ligated, 10 mg/kg AZT. All groups were treated with water or AZT for 10 days. Periodontal tissues were analyzed by morphometric exam, histopathology and immunohistochemical detection of MMP-2, MMP-9, COX-2, RANKL, RANK, OPG, and cathepsin K. Levels of IL-1b, IL-10, TNF-a, myeloperoxidase (MPO), and glutathione (GSH) were determined by ELISA. Treatment with 5 mg/kg AZT resulted in reduced MPO (p˂0.05) and IL-1b (p˂0.05) levels and increased in Il-10 levels (p˂0.05). It was observed a reduced expression of MMP-2, MMP-9, COX-2, RANK, RANKL, cathepsin K, and a increased expression of OPG in the animals subjected to experimental periodontitis and threated with AZT (5 mg/kg). Conclusions: These findings suggest an anti-inflammatory and anti-reabsortive effects of AZT on ligature-induced periodontitis in rats.