Association of IL1 gene polymorphisms with chronic periodontitis in Brazilians

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Association of Haplotypes in the CXCR2 Gene with Periodontitis in a Brazilian Population

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Lack of Association of a Functional Polymorphism in the Interleukin 8 Gene with Susceptibility to Periodontitis

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Effect of selective cyclooxygenase-2 inhibition on the development of ligature-induced periodontitis in rats

Background: the purpose of this study was to evaluate the effect of a selective cyclooxygenase-2 inhibitor on the progression of alveolar bone loss in an experimental periodontitis model in rats.Methods: One hundred eighty (180) Wistar rats were separated into 3 experimental groups. Cotton ligatures were placed at the gingival margin level of lower right first molars. The rats were randomly assigned to one of the following groups that received: a daily oral dose of 10 mg/kg body weight of celecoxib (Ce1); 20 mg/kg body weight of celecoxib (Ce2); or 10 ml/kg of saline solution (C). Serum levels of celecoxib and white blood cell count were determined. Standardized digital radiographs were taken after sacrifice at 3, 5, 10, 18, and 30 days to measure the amount of bone loss around the mesial root surface of the first molar tooth in each rat.Results: Two-way analysis of variance (ANOVA) indicated that groups treated with celecoxib had significantly less bone loss compared to controls (P <0.0001) and that there was a significant interaction between treatment with celecoxib and time (P <0.03). Post-hoc comparisons showed that in both groups treated with celecoxib, the bone loss became significant only after 10 days of ligature placement, while in the control group it was already significant after 5 days. However, differences in mean bone loss between control and Ce1 were significant only at 18 days and, between control and Ce2, at 5 and 18 days. There was no significant difference in bone loss among experimental groups at the end of the experimental period.Conclusion: These data provide evidence that systemic therapy with celecoxib can modify the progression of experimentally induced periodontitis in rats.

Local and cardiorenal effects of periodontitis in nitric oxide-deficient hypertensive rats

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

iNOS-Derived Nitric Oxide Stimulates Osteoclast Activity and Alveolar Bone Loss in Ligature-Induced Periodontitis in Rats

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Role of protease-activated receptor-2 in inflammation, and its possible implications as a putative mediator of periodontitis

Proteinase-activated receptor-2 (PAR2) belongs to a novel subfamily of G-protein-coupled receptors with seven-transmembrane domains. This receptor is widely distributed throughout the body and seems to be importantly involved in inflammatory processes. PAR2 can be activated by serine proteases such as trypsin, mast cell tryptase, and bacterial proteases, such as gingipain produced by Porphyromonas gingivalis. This review describes the current stage of knowledge of the possible mechanisms that link PAR2 activation with periodontal disease, and proposes future therapeutic strategies to modulate the host response in the treatment of periodontitis.

Fluoxetine Inhibits Inflammatory Response and Bone Loss in a Rat Model of Ligature-Induced Periodontitis

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

In vitro adherence of Candida albicans isolated from patients with chronic periodontitis

Adherence is considered an extremely important virulence factor in yeast. Objective: The aim of this study was to analyze the adherence to epithelial cells of C. albicans isolated from patients with chronic periodontitis in comparison to healthy patients. Material and methods: Candida albicans cells isolated from individuals with chronic periodontitis (n=25) and healthy controls (n=25) were included in this study. Suspensions of C. albicans (10(6) cells/rnL) and epithelial cells (10(5) cells/mL) were mixed and incubated at 37 degrees C for 1 h. The number of yeasts adhered to 25 epithelial cells was counted. Results: The number of C. albicans cells adhered to epithelial cells was statistically higher in the chronic periodontitis group than in the control group (Student's t-test, p=0.000). Conclusion: The results of the present study suggest a higher Candida adherence of samples isolated from patients with chronic periodontitis.

Evaluation of two morphometric methods of bone loss percentages caused by periodontitis in rats in different locations

Objective: The present study evaluated morphometrically bone loss percentages in experimental periodontitis in rats, comparing different locations (lingual mandible, palatal maxilla and buccal maxilla) and two evaluation methods (distance and area methods). Material and Methods: Ligatures were placed around the maxillary right second molar and around the mandibular right first molar in 14 female Wistar rats. The contralateral molars served as intragroup control. After 4 weeks, the rats were sacrificed and their mandible and maxilla were removed. The specimens were dissected and stained with methylene blue dye. Bone loss was evaluated by two different methods on the surfaces of the defleshed jaw. In the first method, the distance from the cementoenamel junction (CEJ) to the alveolar bone crest was measured in the roots of teeth associated with ligature. In the second method, the area of bone loss was determined using the alveolar tissue bone, CEJ and the proximal region of roots associated with the ligature as reference. The data were converted to bone loss percentages caused by ligature: (ligated - unligated) x 100/ligated. Results: When comparing the distance and area methods, no statistically significant difference was observed (p>0.05). Both methodologies indicated that the maxilla presented greater bone loss than the mandible and it was more accentuated on the buccal side than on the palatal side (p<0.05). Conclusions: The findings of this study show that both the area and the distance methods can be used to evaluate bone loss caused by ligature placement in rats, and suggest applying the morphometric methodology to the maxilla on the buccal side.

Measurement of the nonlinear optical response of low-density lipoprotein solutions from patients with periodontitis before and after periodontal treatment: evaluation of cardiovascular risk markers

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Cardiovascular Disease Parameters in Periodontitis

Background: Recently, there has been an increasing in the impact of oral health on atherosclerosis and subsequent cardiovascular disease. The aim of this study is to investigate the association between chronic periodontitis and cardiovascular risk markers.Methods: Forty patients with periodontitis and 40 healthy gender-, body mass index-, and age-matched individuals were compared by measuring total cholesterol, high-density lipoprotein, low-density lipoprotein, triglycerides, levels of cytokines, antibodies against oxidized low-density lipoprotein, thiobarbituric acid reactive substances, total and differential white blood cell counts, and the non-linear index of refraction.Results: The levels of triglycerides and high-density lipoprotein in periodontitis patients were significantly higher and lower, respectively (P=0.002 and P=0.0126), compared to controls. Total cholesterol, low-density lipoprotein, and lipid peroxide levels were the same in both groups (P = 0.2943, P = 0.1284, and P = 0.067, respectively). Interleukin (IL)-6 and -8, antibodies against oxidized low-density lipoprotein, and leukocyte and neutrophil counts were significantly higher in periodontitis patients (P<0.05). The value of the non-linear index of refraction of low-density lipoprotein solutions was higher in the controls (P = 0.015) compared to individuals with periodontitis.Conclusion: Our results confirmed and further strengthened the suggested association between coronary artery disease and periodontitis. J Periodontol 2009;80:378-388.