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Objective: Desmarestia anceps Montagne (D. anceps) seaweed has been shown to play a range of biologic activities, such as anti-inflammatory and antioxidant properties. The purpose of this study was to investigate the effects of D. anceps on pathogenesis of ligature-induced experimental periodontitis in rats., Design: Fifty-four male Wistar rats were randomly divided into six groups. Doses of D. anceps (100 and 200 mg/kg) were administered for 14 days to animals with or without ligature-induced periodontitis, in order to compare to control groups (vehicle solution). Morphometric registration of alveolar bone loss and histological analysis were conducted. Inflammatory cells were counted on hematoxylin-eosin-stained slides. Immunohistochemical expressions for interleukin-1 beta (IL-1β), tumor necrosis factor (TNF-α), receptor activator of nuclear factor kappa-Β ligand (RANKL) and bone morphogenetic protein 2 (BMP-2) were evaluated., Results: Alveolar bone loss was higher in groups exposed to ligature-induced periodontitis, but no significant differences were observed comparing different treatment and control groups. Animals that received D. anceps extracts showed significant lower counts of inflammatory cells. D. anceps promoted increased expression of BMP-2 and inhibited IL-1β, TNF-α and RANKL., Conclusion: D. anceps modulates inflammatory response in experimental periodontitis in rats. Further pharmacological and immunological analyses are warranted., Competing Interests: Declaration of Competing Interest All authors of this research (Giliano Nicolini Verzeletti, Eduardo José Gaio, Keilla Gomes Machado, Tobias Rauber Spuldaro, Clarissa Favero Demeda, Rafaele Frassini, André Felipe Streck, Sidnei Moura e Silva, Cassiano Kuchenbecker Rösing, João Antonio Pêgas Henriques and Mariana Roesch-Ely) declare no conflict of interest., (Copyright © 2023 Elsevier Ltd. All rights reserved.)

Adenoid cystic carcinoma (ACC) patients face a highly infiltrative and metastatic disease characterized by poor survival rates and suboptimal response to available therapies. We have previously shown that sensitization of ACC tumors to chemotherapy using histone deacetylase inhibitors (HDACi) constitutes a promising therapeutic strategy to manage tumor growth. Here, we used patient-derived xenografts (PDX) from ACC tumors to evaluate the effects of in vivo administration of the HDAC inhibitor Entinostat combined with Cisplatin over tumor growth. RNA from PDX tumor samples receiving the proposed therapy were analyzed using NanoString technology to identify molecular signatures capable of predicting ACC response to the therapy. We also used an RNAseq dataset from 68 ACC patients to validate the molecular signature identified by the NanoString platform. We found that the administration of Entinostat combined with Cisplatin resulted in a potent tumor growth inhibition (TGI) ranging from 38% to 106% of the original tumor mass. Enhanced response to therapy is consistent with the reactivation of tumor suppressor genes, including SFRP1, and the downregulation of oncogenes like FGF8 and CCR7. Nanostring data from PDX tumors identified a genetic signature capable of predicting tumor response to therapy. We further stratified 68 ACC patients containing RNAseq data accordingly to the activity levels of the identified genetic signature. We found that 23% of all patients exhibit a genetic signature consistent with a high ACC tumor response rate to Entinostat and Cisplatin. Our study provides compelling preclinical data supporting the deployment of a powerful systemic anticancer therapy crafted and explicitly tested for ACC tumors., Competing Interests: None., (AJCR Copyright © 2023.)

For decades, the link between poor oral hygiene and the increased prevalence of oral cancer has been suggested. Most recently, emerging evidence has suggested that chronic inflammatory diseases from the oral cavity (e.g., periodontal disease), to some extent, play a role in the development of oral squamous cell carcinoma (OSCC). The present study aimed to explore the direct impact of biofilm‑induced periodontitis in the carcinogenesis process using a tobacco surrogate animal model for oral cancer. A total of 42 Wistar rats were distributed into four experimental groups: Control group, periodontitis (Perio) group, 4‑nitroquinoline 1‑oxide (4‑NQO) group and 4NQO/Perio group. Periodontitis was stimulated by placing a ligature subgingivally, while oral carcinogenesis was induced by systemic administration of 4NQO in the drinking water for 20 weeks. It was observed that the Perio, 4NQO and 4NQO/Perio groups presented with significantly higher alveolar bone loss compared with that in the control group. Furthermore, all groups receiving 4NQO developed lesions on the dorsal surface of the tongue; however, the 4NQO/Perio group presented larger lesions compared with the 4NQO group. There was also a modest overall increase in the number of epithelial dysplasia and OSCC lesions in the 4NQO/Perio group. Notably, abnormal focal activation of cellular differentiation (cytokeratin 10‑positive cells) that extended near the basal cell layer of the mucosa was observed in rats receiving 4NQO alone, but was absent in rats receiving 4NQO and presenting with periodontal disease. Altogether, the presence of periodontitis combined with 4NQO administration augmented tumor size in the current rat model and tampered with the protective mechanisms of the cellular differentiation of epithelial cells.

The aim of the present study was to analyze the relationship of OM with possible risk factors such as oral health condition, immunological status and IL-1β profile in patients submitted to hematopoietic stem cell transplantation (HSCT). Fifty-four individuals submitted to HSCT were included. All patients received previous dental treatment and photobiomodulation (PBM) as the institutional OM preventive protocol. OM scores, immune status, and IL-1β levels were determined during the conditioning period and at D+3 and D+8 after HSC infusion. IL-1β gene polymorphism was also analyzed during conditioning. Possible associations of OM with risk factors were analyzed using conditional Fisher's exact test. OM was observed in 34 patients (62.9%) classified as Grade 1 (13 patients/24.1%), Grade 2 (14 patients/25.9%), Grade 3 (3 patients/5.5%), and Grade 4 (4 patients/7.4%). Allogeneic HSCT individuals exhibited a higher OM grade than autologous subjects. Moreover, an association was observed between severe OM and severe gingivitis (p = 0.01), neutropenia (p = 0.03), and leukopenia (p = 0.04). A significant association between OM and lower IL-1β levels was detected at three time points, i.e., conditioning (p = 0.048), D+3 (p = 0.01), and D+8 (p = 0.005). The results showed that IL-1β gene polymorphism was not associated with OM. Our study provided important insights into the scope of OM risk factors in the setting of HSCT. Patients submitted to HSCT with severe gingivitis prior to chemotherapy and with severe neutropenia and leukopenia exhibited a higher OM grade. Further investigation will be necessary to better understand the exact role of IL-1β in the context of OM pathobiology and to validate cytokine analysis in larger cohorts.

The aim of this review was to update the evidence of new approaches to non-surgical therapy (NSPT) in the treatment of periodontitis. Preclinical and clinical studies addressing the benefits of adjunctive antimicrobial photodynamic therapy, probiotics, prebiotics/synbiotics, statins, pro-resolving mediators, omega-6 and -3, ozone, and epigenetic therapy were scrutinized and discussed. Currently, the outcomes of these nine new approaches, when compared with subgingival debridement alone, did not demonstrate a significant added clinical benefit. However, some of these new alternative interventions may have the potential to improve the outcomes of NSPT alone. Future evidence based on randomized controlled clinical trials would help clinicians and patients in the selection of different adjunctive therapies.

The multistep process of oral carcinogenesis provides a biological rationale for the use of chemoprevention in individuals at increased risk of developing oral cancer. We aimed to determine if low doses of propranolol can prevent the development of oral cancer using a tobacco-relevant and p53-associated animal model of cancer initiation. Twenty-six Wistar rats were randomly allocated into two groups, vehicle, and propranolol. All animals received 4-nitroquinoline N-oxide (4NQO) at 25 ppm diluted in the drinking water for 20 weeks. Animals from the propranolol group received propranolol (0.1 mg/kg) 5 days per week by gavage for 18 weeks. The clinical analysis was performed by measuring the area of the lesion and assessment of scores based on lesion appearance (papule; plaque; nodule or ulcerated). Histopathological analysis was performed to determine the presence of epithelial dysplasia or invasive squamous cell carcinoma (SCC). The average lesion area in 4NQO + vehicle and in 4NQO + propranolol groups were 0.20  and 0.28 mm2, respectively (P = 0.53). The percentage of cases clinically graded as papules, thick plaques, nodular areas, and ulcerated lesions was similar between groups (P = 0.94). Histopathological diagnosis also did not differ between groups (P = 0.65), with 54.5 and 70% of cases being diagnosed as SCC in 4NQO and in 4NQO + propranolol groups, respectively. In conclusion, daily doses propranolol at 0.1 mg/kg were not as effective as a chemopreventive therapy in an animal model of 4NQO-induced carcinogenesis., (Copyright © 2020 Wolters Kluwer Health, Inc. All rights reserved.)

Aim: To assess obesity as a risk factor for tooth loss over 5 years in an urban sample of Brazilian adults., Materials and Methods: A total of 1586 individuals were surveyed using a multistage probabilistic approach. Five years later, 635 individuals 14-64 years old were re-examined. An incident case of tooth loss was determined for a participant that had lost at least one tooth over time. Obesity was evaluated by calculating body mass index at baseline and by the change in obesity status over time., Results: Incident cases of tooth loss were significantly more frequent among obese (47.1%) than normal-weight individuals (32.4%) (p = .004). Obese individuals had 31% higher risk [relative risk (RR) =1.31; 95% confidence interval (95%CI) 1.04-1.65] for tooth loss than normal-weight individuals adjusting for age, socio-economic status, smoking, dental care and periodontitis. This association was significant for females (RR=1.47, 95%CI 1.08-2.01), but not for males. The risk for tooth loss was also modified by presence of periodontitis at baseline and lifetime smoking exposure. There was an increased risk for tooth loss for those that remained obese than those that remained normal weight., Conclusion: Obesity is associated with higher risk for tooth loss. This association was modified by sex, periodontal status and smoking., (© 2020 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.)

The purpose of this study was to evaluate aortic wall thickness after periodontal disease and/or obesity induction in a Wistar rat model.Sixty male Wistar rats were randomly divided into four groups: control (CT), periodontal disease (PD), obesity (OB), and obesity plus periodontal disease (OB+PD). Groups OB and OB+PD received cafeteria diet for 17 weeks. After they had acquired obesity (week 12), periodontal disease was induced by placing a silk ligature on the maxillary right second molar of groups PD and OB+PD. During the experimental period, body weight and Lee index were assessed. Mean alveolar bone loss (ABL) was evaluated, and aortas were prepared for histometric analysis of the aortic wall by ImageJ software. Body weight and Lee index increased in rats exposed to cafeteria diet. Mean ABL was higher in Groups PD and OB+PD than in control and OB (p<0.05). ABL was 18% higher in Group OB+PD than in Group PD, with statistically significant difference (p<0.001). Aortas were thicker in Groups OB and OB+PD than in control and PD groups, respectively (2.31mm ± 0.28 and 2.33 ± 0.29 vs. 2.18 ± 0.26 and 2.14 ± 0.27). Group OB differed significantly from the control group (p=0.036), and OB+PD and OB differed significantly from PD (p=0.004 and p= 0.001, respectively). Obesity alters aortic wall thickness in Wistar rats. However, the presence of periodontal disease did not affect the aortic wall thickness under the conditions of the present study.

Objectives: To evaluate the influence of red wine exposure, alcohol, grape juice and resveratrol in the occurrence of spontaneous and ligature induced periodontitis as well as CRP, TNFα and IL-6 levels in Wistar rats., Methodology: 50 male Wistar rats were randomly assigned to 5 groups (Control, Red Wine, Grape Juice, 12% Alcohol and 0.05mg/mL Resveratrol). All groups were fed with laboratory rat chow and liquid intake according to group allocation. After 8 weeks, ligatures were placed around the maxillary right second molars. The contra-lateral molars remained as intra-group controls. After 14 days, animals were killed, blood samples collected and specimens prepared for analysis. Group comparisons were performed by ANOVA. A cut-off point in the 75th percentile in the side without ligature was used for definition of spontaneous periodontitis., Results: All animals completed the experiment. According to mean alveolar bone loss, no statistically significant differences were found. Animals exposed to red wine presented a lower occurrence of spontaneous periodontitis, lower levels of TNF-α (0.97 ng/mL) and CRP (0.29 mmol/μL) compared to controls (1.97 ng/mL, p = 0.008 and 0.45 mmol/ μL, p less than or equal to 0.05 respectively)., Conclusion: Red wine exposure potentially affects the occurrence of spontaneous periodontitis, CRP and TNF-α levels in Wistar rats., Competing Interests: The authors declare not to have conflicts of interest., (Copyright© by the International Academy of Periodontology.)

This study aimed to assess the effects of low molecular weight heparin (LMWH) on alveolar bone loss (ABL), blood count, and counting of megakaryocytes and adipocytes in male Wistar rats. Forty male 60-day Wistar rats were randomly divided into four groups: Control (C), Periodontal Disease (PD), Heparin (Hp) and Heparin + Periodontal Disease (Hp+PD). LMWH was applied for 60 days at doses of 1 ml/kg/day. Blood samples were collected at baseline, 30 and 60. On day-49, PD and Hp+PD groups were subjected to ligature-induced periodontitis around second upper right molar. The left side was assessed as spontaneous alveolar bone loss. Mean ABL in the side with ligature showed significantly different between C (0.35±0.07 mm) and Hp+DP (0.49±0.09 mm) groups (p<0.001), between PD (0.55±0.11 mm) and Hp (0.32±0.06 mm) groups (p<0.001) and between Hp and Hp+DP groups (p<0.001). No significant differences were found among groups for ABL in the side without ligature. Animal weight, food intake, and water consumption showed no statistically significant difference among groups. Megakaryocytes and adipocytes were counted using optical microscopy and no statistically significant differences were found. Within-groups, there were an increase and a decrease, respectively, in the counting of lymphocytes (p=0.005 for C and p=0.009 for Hp+PD groups only) and leukocytes (p=0.003 for C, p=0.001 for PD, p=0.002 for Hp, and p<0.001 for Hp+PD groups). There was no decrease in the number of platelets in the three collection periods. LMWH was not able to affect ABL, but it may change the blood counting, especially increasing lymphocytes.

Objective: This study evaluated the effect of an experimental carcinogenic, 4-Nitroquinoline 1-oxide (4NQO), in the spontaneous alveolar bone loss (ABL) in an animal model., Design: Twenty-two male Wistar rats were included in this study. They were randomly divided into two groups: the control group (n = 10) received food and water ad libitum, and the test group (n = 12) receive the same food; however, 25 ppm of 4NQO was diluted in the drinking water. All animals were euthanized after 20 weeks, and the tongues were removed and analyzed macroscopically to determine the presence of oral mucosal lesions. All specimens were paraffin-embedded and histological sections were obtained. The microscopic analysis was based on routine procedure (haematoxylin and eosin stain). The analysis of spontaneous ABL was performed by a calibrated examiner using standardized photographs and imaging software. Differences in spontaneous ABL were assessed among the three resulting groups: control, 4NQO with oral squamous cell carcinoma (OSCC), and 4NQO without OSCC., Results: In the 4NQO-treated group, nine animals developed OSCC. The animals in the 4NQO with OSCC group presented significantly more spontaneous ABL (0.65 ± 0.21 mm) than the control group (0.34 ± 0.05) (p < 0.001). The animals in the 4NQO without OSCC group showed a mean spontaneous ABL of 0.47 ± 0.13 mm, which was not statistically significant different when compared to the control group (p = 0.096)., Conclusions: It was concluded that the presence of OSCC enhanced spontaneous ABL in Wistar rats when compared to control animals. Additionally, it was shown that, solely, administration of 4NQO may not be considered responsible for alveolar bone destruction., (Copyright © 2018 Elsevier Ltd. All rights reserved.)

This study aimed to evaluate the anti-plaque and anti-gingivitis effects of two mouthwashes containing cetylpyridinium chloride (CPC), in comparison to negative control mouthwash. One hundred and twenty subjects were randomly assigned to study groups: test (0.075% CPC and 0.28% zinc lactate), positive control (0.07% CPC) and negative control mouthwash without CPC. All volunteers were examined by a calibrated examiner for the Quigley-Hein Plaque Index (Turesky modification) and Löe-Silness Gingival Index (GI). Gingival severity was also measured by the percentage of sites with positive gingival bleeding. During six weeks, oral hygiene consisted of brushing twice daily with a toothbrush and toothpaste and rising with their assigned mouthwash. Plaque and gingival parameters were assessed at baseline, after four and six weeks of product use. Statistical analyses were performed separately for plaque and gingival indices, by ANOVA, paired t-test and ANCOVA (α < 0.05). After 4 and 6 weeks, all mouthwashes groups presented statistically significant reductions in plaque and gingival parameters as compared to baseline. In comparison to the positive control, the test group presented additional reductions in dental plaque of 19.8% and 16.8%, after 4 and 6 weeks, respectively. For GI, the additional reductions in the test group were 9.7% and 14.3%, at 4 and 6 weeks, respectively. The test group showed additional reduction of 35.3% and 54.5% in the gingival severity, at week 4 and 6, respectively. It is concluded that the mouthwash containing CPC and zinc lactate presents significant anti-plaque and anti-gingivitis effects as compared to positive and negative control mouthwashes.

The aim of the present work was to evaluate the effect of different times on alveolar bone loss (ABL) and whether the presence of ligature on one side affects ABL on the contralateral site. This is a secondary analysis of databases from studies conducted at the Federal University of Rio Grande do Sul. Included studies used ligature-induced periodontal disease in rats. In order to be included, the studies were required to have a control group without any ligatures and an intra-group control. Three studies were included, which used different time periods: 2 weeks with ligature and 8 weeks without ligature; 5 weeks with ligature and 17 weeks without ligature; 22 weeks with and without ligature. Animals were raised similarly and sacrificed by decapitation. Maxillae were defleshed with 9% sodium hypochlorite. Pictures were taken and five measurements were obtained from each image. The presence of ligature generated significantly greater ABL compared to sides without ligature. Comparing sides with ligature, ABL was lower at 2 weeks than at 5 and 22 weeks. Sides without ligature showed no significant difference between 8 and 17 weeks for spontaneous periodontitis. However, after 22 weeks, animals exhibited significantly greater ABL when compared to other periods. The presence of ligature on one side did not influence ABL on the contralateral side. Two weeks of ligature-induced periodontal disease seems to be sufficient to demonstrate significant ABL. Teeth without ligature contralateral to teeth with ligature may be considered sound controls, thereby reducing the amount of animals needed in periodontal research., (Sociedad Argentina de Investigación Odontológica.)

The aim of this study was to compare the efficacy in supragingival plaque removal of two soft-bristle toothbrushes. Seventy volunteers were allocated randomly to the Colgate Slim Soft or Curaprox CS5460 toothbrush grourps. At baseline appointment, volunteers underwent plaque examination using the Rustogi Modification of the Navy Plaque Index. Under supervision, they then brushed their teeth for 1minute with their assigned toothbrushes and the plaque examination was repeated. Volunteers performed daily oral hygiene with their assigned toothbrush and a regular dentifrice provided by the researchers for 7 days. The baseline experimental procedures were then repeated. Separate analyses of variance were performed for the whole-mouth, interproximal, and gumline plaque scores (p < 0.05). No difference in baseline pre-brushing scores was found between groups. After a single toothbrushing, the mean plaque score was significantly reduced in both groups (p < 0.05), with greater reduction of whole-mouth and interproximal plaque scores observed in the SlimSoft group compared with the Curaprox group (p < 0.05). After 7 days, the SlimSoft group showed greater reduction of the whole-mouth and interproximal plaque scores compared with the Curaprox group (p < 0.05). In conclusion, the SlimSoft toothbrush presented greater efficacy in supragingival plaque removal than did the Curaprox CS5460 toothbrush, as reflected by whole-mouth and interproximal plaque scores.

Aim: The aim of this study was to assess the effect of overweight and obesity on periodontal attachment loss (PAL) progression in an urban population from south Brazil., Methods: In 2001, a population-based oral health survey entitled "Epidemiology of periodontal diseases: the Porto Alegre Study" was conducted by drawing a probabilistic sample of 1586 individuals. After 5 years, 755 (participation rate: 47.6%) individuals were re-examined. For this analysis, self-reported diabetics, underweight individuals, and individuals with <6 teeth were excluded. Poisson regressions were used to calculate relative risks (RR) and 95% confidence intervals (CI) adjusted for sex, age, skin colour, education, socio-economic status, smoking and dental care., Results: Five hundred and eighty-two individuals (333 males/249 females, 36.02 ± 14.97 years) were included. Overall, obese individuals had significantly higher risk of experiencing PAL progression than individuals with normal weight after adjusting for important co-factors (RR = 1.36, 95% CI = 1.04-1.78). In a stratified analysis, no statistically significant associations were observed between PAL progression and obesity for males (RR = 1.13, 95% CI = 0.75-1.69), whereas obese females were at statistically significant higher risk than normal weight females (RR = 1.64, 95% CI = 1.11-2.43)., Conclusion: Obesity appears to be a risk factor for PAL progression for females but not males in this developing country population., (© 2016 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.)

The aim of the present study was to evaluate the effect of 15% alcohol dependence on ligature-induced alveolar bone loss and TNF-α secretion in Wistar rats. Thirty-three male Wistar rats aged 45-60 days (mean weight=253 g) were randomly allocated test or control groups. Test group (n=18) received 15% alcohol as liquid intake and control group (n=15) received water during the experimental period. TNF-α was analyzed by ELISA assay in 11 animals per group. After 14 days of alcohol/water intake, alcohol dependency was assessed and silk ligatures were placed around the left second upper molars. Ligature presence and body weight were checked weekly. After 40 days, animals were sacrificed and the maxillae were defleshed for morphometric analysis using standardized images. All animals in the test group displayed signs of alcohol dependency at day 14. No statistically significant differences in final body weight (334.83±21.38 vs. 322.48±30.65 g, p=0.20) were observed between groups. In relation to alveolar bone loss, no statistically significant difference was observed among test and control groups both for ligated teeth (0.76±0.06 vs. 0.74±0.10 mm, p=0.60) and unligated teeth (0.41±0.16 vs. 0.35±0.05 mm, p=0.22). The TNF-α secretion also did not display statistically significant differences between test and control groups (10.78±1.84 vs. 12.13±2.11 pg/mL, p=0.12). It may be concluded that 15% alcohol dependency was not capable to alter alveolar bone loss and TNF-α secretion in Wistar rats.

Background: A positive association between obesity-associated metabolic disorders (e.g., hyperlipidemia and diabetes) and periodontitis has been demonstrated in the literature. This study evaluates the role of cafeteria diet-induced obesity/hyperlipidemia (CAF) on alveolar bone loss (ABL) in rats., Methods: Sixty male Wistar rats were randomly divided in four groups: control, periodontitis (PERIO), obesity/hyperlipidemia (CAF), and obesity/hyperlipidemia plus periodontitis (CAF+PERIO). Groups CAF and CAF+PERIO were exposed to a high-fat, hypercaloric diet. At week 12, periodontal disease was induced in groups PERIO and CAF+PERIO by ligatures in the upper second molar. The contralateral tooth was considered the intragroup control. Body weight and Lee index were evaluated weekly during the experiment. Serum glucose and cholesterol/triglycerides in the liver were evaluated, and percentage of ABL was measured by microcomputed tomography. Serum tumor necrosis factor (TNF)-α and interleukin (IL)-1β were evaluated by enzyme-linked immunosorbent assay at week 17., Results: Body weight, Lee index, and cholesterol/triglycerides in the liver increased in groups exposed to the cafeteria diet. Groups PERIO and CAF+PERIO exhibited a significantly higher ABL compared to control and CAF groups. The presence of obesity and hyperlipidemia significantly increased ABL in the CAF+PERIO group compared to the PERIO group (53.60 ± 3.44 versus 42.78 ± 7.27, respectively) in the sides with ligature. Groups exposed to CAF exhibited higher ABL in the sides without ligature. No differences were observed among groups for IL-1β and TNF-α., Conclusion: Obesity and hyperlipidemia modulate the host response to challenges in the periodontium, increasing the expression of periodontal breakdown.

Purpose: To compare the effect of toothbrushing abrasion with hydrated silica-based whitening and regular toothpastes on root dentin using contact profilometry., Materials and Methods: Ninety dentin specimens (4 x 4 x 2 mm) were randomly divided into five experimental groups (n = 18) according to the toothpaste: three whitening (W1, W2 and W3) and two regular toothpastes (R1 and R2) produced by two different manufacturers. Using a brushing machine, each specimen was brushed with a constant load of 300 g for 2500 cycles (4.5 cycles/s). The toothpastes were diluted at a ratio of 1:3 w/w (dentifrice:distilled water). The brush diamond tip of the profilometer moved at a constant speed of 0.05 mm/s with a force of 0.7 mN., Results: The average value of brushing abrasion in μm (mean ± SD) was obtained from five consecutive measurements of each specimen: W1 = 8.86 ± 1.58, W2 = 7.59 ± 1.04, W3 = 8.27 ± 2.39, R1 = 2.89 ± 1.05 and R2= 2.94 ± 1.29. There was a significant difference between groups (ANOVA, p<0.0001). Post-hoc Tukey's test for multiple comparisons showed differences between all the whitening and regular toothpastes, but not among the whitening nor among the regular toothpastes., Conclusion: The whitening toothpastes tested can cause more dentin abrasion than the regular ones.

Few population-based cohort studies have been established in Dentistry and this is especially true for Latin America. We conducted a population-based prospective study focusing on oral health in Porto Alegre, south Brazil, and herein we describe its methodology and discuss directions for further research. The cohort was established in 2001 using a multistage probability sample of 1,465 toothed and 121 edentulous subjects. A 5-year follow-up was performed in 2006 that included 755 individuals. The main aim of this study was to determine the pattern and risk factors for periodontal disease progression and tooth loss incidence. A full-mouth protocol was used including periodontal assessments at six sites per tooth. Primary outcomes were periodontal attachment loss and tooth loss. Oral mucosal lesions, dental plaque, gingivitis, supragingival calculus, probing depths, gingival recession, and dental caries were also assessed. This is the first population-based cohort study to focus on periodontal disease in Latin America. Findings will contribute to our understanding of the epidemiology of periodontal disease and provide valuable data for the planning and implementation of preventive and therapeutic strategies.

Gingival recession is characterized by the apical migration of the gingival margin, exposing the root surface. Studies have demonstrated several etiological factors for gingival recession such as periodontitis, traumatic toothbrushing, use of oral piercing, and past orthodontic therapy, among others. It might not be possible to identify and quantify the influence of each factor, and gingival recession at some sites may be the result of the combination of these factors. Gingival recession affects individuals at all ages, with prevalence increasing as time passes. The aim of this study was to observe whether there is correlation between gingival thickness and gingival recession. Fifty-five subjects of both genders aged 18-35 years participated in the study. The volunteers were under treatment at the School of Dentistry of the Federal University of Rio Grande do Sul. Buccal gingival thickness was measured on incisors, canines and bicuspids, under anesthesia, following inclusion and exclusion criteria. Statistical analysis was performed with STATA version 10.1. The results had a Pearson Correlation Coefficient of -0.216. Linear regression had a statistically significant pvalue of 0.025. It may be concluded that there is weak negative correlation between gingival thickness and gingival recession.

Background: Certain drugs such as glucocorticoids may interfere with the modulation of periodontal disease. In contrast, corticosteroid treatment has been associated with a protective effect with regard to periodontal breakdown, depending on the dose, pathway, and exposure time. Considering the potential relevance of nucleotidases in coordinating the cardiovascular system and inflammation processes, the aim of this study was to investigate the nucleotidase activities in the blood serum of rats with periodontal disease exposed chronically to inhaled corticosteroids., Methods: Adult male Wistar rats (n=26) were randomly assigned to one of the following four study groups: a control group that received no intervention; a periodontal disease group that received saline solution; a 'low dose' group that received 30 μg of budesonide daily; and a corresponding 'high dose' group that received 100 μg daily over a 15-day time course. The hydrolysis of ATP, ADP, and AMP were analysed in blood serum., Results: Periodontal disease diminished the hydrolysis of ATP and enhanced the hydrolysis of ADP. Repeated administration of either a low or high dose in the periodontal disease model of inhaled corticosteroids reversed the observed increase in ADP hydrolysis, and only the repeated administration of low doses of inhaled corticosteroids was able to reverse the decrease in the hydrolysis of ATP induced by periodontal disease., Conclusion: The variables investigated in this study may be involved in the pathophysiology of periodontal disease and may participate in the mechanisms that mediate the development of some of the side effects of inhaled corticosteroids., (Copyright © 2014 Elsevier Ltd. All rights reserved.)

The aim of the present study was to evaluate the effect of alcohol and/or tobacco exposure on spontaneous alveolar bone loss in Wistar rats. Twenty-four, male, 60 day-old, Wistar rats were assigned to 4 groups: Group 1 received 10 mL/kg of glucose solution (5%). Group 2 received 2 g/kg alcohol (20%). Group 3 was exposed to tobacco smoke (6 cigarettes/60 min). Group 4 received both interventions of groups 2 and 3. Alcohol was given by gastric gavage and cigarette exposure was performed using a forced ventilation chamber. After 30 days, animals were sacrificed and the upper maxillae removed and defleshed. Morphometric analysis of alveolar bone loss (ABL) around the second molar was performed in standardized digital photographs. Statistical analysis was conducted using paired t-test, one-way ANOVA and occurrence of spontaneous periodontal disease (ABL ≥ 0.39 mm) was analyzed by Fisher's exact test. Significant differences in body weight were observed between all groups. Group 2 presented higher body weight as compared to the 3 other groups at 4 weeks (p≤0.05). Mean ABL values were 0.31 mm (±0.08), 0.29 mm (±0.07), 0.33 mm (±0.10), and 0.33 mm (±0.08) for groups 1, 2, 3, and 4, respectively. No significant differences were found among groups. In the analysis of occurrence of periodontal breakdown, alcohol exposure decreased the occurrence of ABL and cigarette exposure increased ABL. The combination of alcohol and cigarette exposure did not differ from the control group. Alcohol consumption decreased the occurrence of periodontal breakdown, while tobacco increased this rate.

Objective: To evaluate the effect of body weight on the occurrence of spontaneous alveolar bone loss in Wistar rats., Methods: Twenty-eight rats were randomly divided in two groups. Control group received standardized rat chow diet and water. Test group received cafeteria (CAF) diet during 17 weeks. Diet was available for both groups ad libitum. Body weight and Lee Index were evaluated. At the end of the experimental period, rats were killed by decapitation and maxillae were defleshed with 9% sodium hypochlorite. Morphometric analysis was performed in digital standard photographs. Presence of spontaneous periodontitis was considered when mean alveolar bone loss was ≥0.51mm (75th percentile). Statistical analysis was performed with chi-square test, Mann-Whitney test and independent samples t-test (significance level P≤0.05)., Results: After 17 weeks of exposure to standard CAF diet, a statistically significant mean difference in body weight (g±SD) (478±43 vs. 580±60) and Lee Index (3.07±0.05 vs. 3.24±0.07) was observed between control and obesity groups, respectively. Median (interquartile range) of alveolar bone loss in control group was 0.344 (0.313-0.367) and 0.491 (0.427-0.506) for buccal and palatal site, respectively. For obese group was 0.308 (0.289-0.354) and 0.549 (0.482-0.616) for buccal and palatal site, respectively. In animals submitted to CAF diet, 20 sites were classified as spontaneous periodontal disease, whereas in control animals, only 8 sites exhibited periodontal breakdown according cut-off point. A significant difference between groups was detected (P=0.009)., Conclusions: It may be concluded that obesity increases the occurrence of spontaneous periodontal disease in Wistar rats., (Copyright © 2013 Elsevier Ltd. All rights reserved.)

The aim was to correlate alveolar bone loss in the buccal/palatal and the mesial/distal surfaces of upper molars in rats. Thirty-three, 60-day-old, male Wistar rats were divided in two groups, one treated with alcohol and the other not treated with alcohol. All rats received silk ligatures on the right upper second molars for 4 weeks. The rats were then euthanized and their maxillae were split and defleshed with sodium hypochlorite (9%). The cemento-enamel junction (CEJ) was stained with 1% methylene blue and the alveolar bone loss in the buccal/palatal surfaces was measured linearly in 5 points on standardized digital photographs. Measurement of the proximal sites was performed by sectioning the hemimaxillae, restaining the CEJ and measuring the alveolar bone loss linearly in 3 points. A calibrated and blinded examiner performed all the measurements. Intraclass Correlation Coefficient revealed values of 0.96 and 0.89 for buccal/lingual and proximal surfaces, respectively. The Pearson Correlation Coefficient (r) between measurements in buccal/palatal and proximal surfaces was 0.35 and 0.05 for the group treated with alcohol, with and without ligatures, respectively. The best correlations between buccal/palatal and proximal surfaces were observed in animals not treated with alcohol, in sites both with and without ligatures (r = 0.59 and 0.65, respectively). A positive correlation was found between alveolar bone loss in buccal/palatal and proximal surfaces. The correlation is stronger in animals that were not treated with alcohol, in sites without ligatures. Areas with and without ligature-induced periodontal destruction allow detection of alveolar bone loss in buccal/palatal and proximal surfaces.

Objective: To assess the oral health status of community-dwelling adults aged 60 years and older from southern Brazil and to determine demographics, socioeconomic, behavioural and dental risk indicators., Materials and Methods: This cross-sectional study used a multistage, probability sampling method to draw a representative sample of the metropolitan area of Porto Alegre, Brazil. A subsample of 217 subjects was included in this analysis. Oral mucosal lesions, dental caries, tooth loss and periodontal status (full-mouth, six sites per tooth exam) were assessed by calibrated examiners., Results: Prevalence of edentulism was 39.5%, and mean tooth loss was 20.2 (SE = 0.6). Older individuals [Odds Ratio (OR) = 2.2], women (OR = 2.3), white people (OR = 5.9), individuals of lower socioeconomic status (OR = 5.6) and smokers (OR = 3.5) had higher likelihood of being edentulous. Approximately 36% of dentate individuals had caries and/or restoration affecting, in average, 5.0 teeth. Periodontitis affected 79% of subjects, and it was associated with older age (OR = 4.0), men (OR = 3.4) and large amounts of supragingival plaque (OR = 3.0)., Conclusion: Poor oral health was observed in this elderly population from South Brazil. Sociodemographic disparities accounted for most of the burden of disease and treatment needs., (© 2012 The Gerodontology Society and John Wiley & Sons A/S.)

Unlabelled: Obesity has been linked to higher inflammatory status and periodontal breakdown., Objective: The purpose of this study was to investigate the effect of obesity on alveolar bone loss in experimental periodontitis in rats., Material and Methods: Twenty-four female Wistar rats were randomly divided into two groups: obese (n=13), which were fed with "cafeteria diet" (CAF diet--high amounts of sucrose and fat) for 90 days in order to gain weight, and non-obese (n=11) regularly fed rats. Ligature-induced experimental periodontitis was created in all animals. Body weight differed statistically between obese and non-obese groups (277.59 and 223.35 g, respectively) at the moment of the ligature placement. Morphometric registration of alveolar bone loss was carried out after 30 days of ligature placement to determine the effect of obesity on the progression of experimental periodontitis., Results: Intra-group comparisons showed significantly higher alveolar bone loss mean values in maxillary teeth with ligature (P<0.05). Alveolar bone loss [mean (SD), mm] was not statistically different between obese and non-obese groups [0.71 (0.09) and 0.65 (0.07) mm, respectively]. However, when palatal sides are analyzed separately, obese group presented significantly higher alveolar bone loss (P<0.05) as compared to non-obese [0.68 (0.12) and 0.53 (0.13) mm, respectively]., Conclusions: In spite of the weak differences, it is possible to conclude that the progression of alveolar bone loss in ligature-induced periodontitis can be potentially influenced by body weight in rats.

Aim: The aim of this 5-years longitudinal study was to investigate the pattern and rate of periodontal attachment loss (PAL) progression in an urban population in South Brazil., Methods: In 2001, a multistage probability sampling strategy was used to derive a representative sample of 1,465 dentate individuals from Porto Alegre, Brazil. Five years later, 697 dentate individuals (294M/403F, mean age: 37.9 ± 13.3) were available for follow-up. PAL was assessed by calibrated examiners using a full-mouth protocol. Estimates of proximal PAL progression and standard errors (SE) are reported., Results: Fifty-six per cent (SE: 1.9) and 36% (SE: 1.8) of subjects showed PAL progression ≥3 mm affecting ≥2 and ≥4 teeth respectively. PAL progression ≥3 mm was mostly localized affecting 3.8 (SE: 0.2) teeth and 5.7 (SE: 0.3) sites. Annual PAL progression was, on average, 0.3 mm (SE: 0.01). Significant differences in PAL progression were observed according to age, gender, race and socioeconomic status. PAL progression increased with age reaching the highest progression rate in the 40-49 years cohort, and then decreased in older age groups. PAL progression was consistently higher among males and non-Whites than females and whites., Conclusion: A large proportion of this urban Brazilian sample was affected by PAL progression underscoring the need for health promotion initiatives aiming at preventing progression of destructive periodontal disease., (© 2011 John Wiley & Sons A/S.)

Objective: To evaluate the effect of different concentrations of inhaled budesonide on secretion of tumoral necrosis factor-alpha (TNF-α) and on ligature-induced alveolar bone loss in Wistar rats., Materials and Methods: Forty-two animals were randomly divided in four groups. Control group (G1) did not receive any procedure. For the other 3 groups, alveolar bone loss was induced by placement of ligatures around the upper second molar. The contralateral molar was considered intra-group control. Group 2 (G2) was nebulized with saline solution (NaCl 0.9%). Groups 3 and 4 (G3 and G4) were nebulized with 30 μg and 100 μg budesonide, respectively. Administration of drugs was performed daily for 14 days. Blood samples were collected from all animals for analysis of TNF-α. The maxillae from G2, G3 and G4 were removed and defleshed with 9% sodium hypochlorite. Morphometric analysis of bone loss was performed in digital standard photographs. Statistical analysis was performed with one-way ANOVA, followed by Tukey HSD or Scheffé multiple comparison's test (significance level P ≤ 0.05)., Results: Mean alveolar bone loss values for teeth with ligature were 0.72, 0.70 and 0.77 mm for Groups 2, 3 and 4, respectively. No statistically significant differences were found amongst groups with or without ligature. The production of TNF-α was 60% higher in the presence of ligature (G1 vs. G2/G3/G4). No effect was observed in TNF-α secretion after inhalation of budesonide., Conclusion: Inhaled budesonide in different concentrations did not alter alveolar bone loss and TNF-α secretion in male Wistar rats., (Copyright © 2011 Elsevier Ltd. All rights reserved.)

Objective: The aim of the present study was to evaluate the influence of ethanol in low concentration (5%) in ligature-induced alveolar bone loss in Wistar rats., Material and Methods: Thirty rats were randomly assigned to test and control groups (n=15). Test group received a liquid diet containing ethanol 5% (vol./vol.) and standard rat chow. Control group received only tap water as the liquid diet and the same rat chow. In both groups, diet was delivered ad libitum. Alveolar bone loss was induced prior to the beginning of the study by means of ligatures placed around the upper second molars. The contra-lateral tooth remained as intra-group control. At the end of the nine weeks, the animals were killed and morphometric analysis of alveolar bone loss was performed by a blinded and calibrated examiner. Intra-group comparisons were performed by paired sample T-test and inter-group differences were compared by independent sample T-test (α=.05)., Results: Animals that drank ethanol in low concentration systematically presented less alveolar bone loss than the control group, regardless of the presence of ligature. Test group showed less alveolar bone loss (p=0.04) in unligated teeth when compared to control group (0.32 ± 0.07 and 0.37 ± 0.07 mm, respectively). However, no significant difference (p=0.14) was observed between Test and Control groups (0.78 ± 0.14 and 0.84 ± 0.18 mm, respectively) in ligated teeth., Conclusion: The results of this study lead to the conclusion that low concentration alcohol intake did not affect the alveolar bone loss in ligature induced periodontal breakdown., (Copyright © 2010 Elsevier Ltd. All rights reserved.)

There are many studies that evaluate possible risk factors for periodontal diseases in animals. Most of them have focused only on the biological aspects of disease occurrence; therefore, it has been difficult to compare studies of the different methodological approaches. The aim of the present study was to compare different methods - linear and area - of the evaluation of morphometrical alveolar bone loss. Sixty hemimaxillae, defleshed and stained with 1% methylene blue to delineate the cementoenamel junction and alveolar bone crest, were obtained from a previous study that induced periodontal disease by means of ligatures in two groups of fifteen Wistar rats during 9 weeks. Ligatures were placed around the right upper second molars, and the contra-lateral teeth remained as intra-group controls. Digital photographs were taken from the specimens and submitted to a single, calibrated, blind examiner who performed the morphometrical evaluation of alveolar bone loss using both linear and area methods. Mean values of linear and area measurements were obtained from each side - buccal and palatal - of the specimens. The degree of association between the two methods was determined by Pearson's Correlation Coefficient. An almost perfect association (0.98) was determined between the linear and area evaluations. A mathematical formula was subsequently created to estimate the total area of alveolar bone loss, from linear mean measurements. Both methods were suitable for detecting bone level alterations. The results of the present study allow for the transformation of data and better compilation of results from different studies.

Objective: A recent consensus report could not find specific reports of the effect of nifedipine on the destruction of the periodontal tissues. The aim of the present study was to evaluate the effect of nifedipine on gingival enlargement and periodontal breakdown using a ligature-induced periodontitis in rats., Materials and Methods: Fifty, male, 60 days old, Wistar rats, were divided into six groups. Cotton sutures were placed around the upper second molars. Two groups of 10 rats each did not receive ligatures and were treated daily with either saline solution or nifedipine 50mg/kg/day. Two groups of 10 rats received ligatures and were also treated daily with saline solution or nifedipine 50mg/kg/day. Two additional groups (nifedipine 10 and 100mg/kg/day) were included to explore a possible dose-response relationship. Animals were euthanatised at 30 days. Internal and oral epithelium, total and inflamed connective tissue, gingival thickness and height, and bone loss were assessed histologically., Results: Nifedipine alone was not sufficient to promote gingival enlargement or periodontal destruction in the absence of the ligature. Compared to animals with ligatures only, the group that received ligatures and nifedipine 50mg/kg/day showed significant higher estimates for total and inflamed connective tissue, gingival thickness and height. No significant differences were observed for bone loss between these experimental groups. The other dosages of nifedipine did not provide additional information., Conclusion: Nifedipine itself did not lead to gingival enlargement in rats. In the presence of biofilm accumulation, nifedipine yielded greater gingival enlargement and periodontal inflammation, but it did not increase periodontal destruction., (2010 Elsevier Ltd. All rights reserved.)

Objective: The aim of this study was to verify the association between an endogenous depression model and the development of ligature-induced periodontitis in rats., Material and Methods: Nine male Lewis rats received 30 mg/kg clomipramine from neonatal day 8 to day 21 (depressed group), while 13 control Lewis rats were left untouched (control group). On day 150, ligatures were placed around the 2nd upper molars in both groups, i.e. the contralateral molar of the intra-group control. On day 190, the rats were killed and the maxillae were defleshed. The distance between the cemento-enamel junction and the alveolar bone crest was measured by a blinded examiner using standardized digital photographs., Results: The depressed rats showed hyperactivity in open field on day 142 and greater attempts to escape on day 143 compared to controls. The other behavioral data did not show statistically significant differences between the groups (Mann-Whitney, p>0.05). In teeth with ligature, mean alveolar bone loss varied from 0.51 to 0.60 and from 0.63 to 0.64 mm for tests and controls, respectively (t-test, p>0.05). In teeth without ligature, these values varied from 0.38 to 0.43 and 0.42 to 0.45 mm in the test and control groups, respectively (t-test, p>0.05)., Conclusion: Induced depression did not alter ligature-induced bone loss in Lewis rats.

Objective: The aim of this study was to compare ligature-induced alveolar bone loss between obese and non-obese rats., Material and Methods: Thirty female Wistar rats were randomly divided into two groups: a test group comprising 14 rats fed with a "cafeteria diet" for 120 days in order to gain weight and a control group comprising 16 regularly fed rats. Ligatures were placed around the 2nd upper molars, and the contralateral teeth served as intra-group controls. After 30 days, the animals were killed and the maxillae were removed. Sodium hypochlorite was used to prepare the specimens, and the cementum-enamel junction was stained with methylene blue 1%. Morphometric analysis of alveolar bone loss was by standardized digital photographs and the distance between the cementum-enamel junction and the alveolar bone crest was measured using the software Image Tool 3.0., Results: Body weight differed statistically between test and controls (268.6 and 242.4 g, respectively). Test animals demonstrated a mean (SD) alveolar bone loss of 0.51 (0.11) mm and in the controls 0.52 (0.14) mm in teeth with ligatures. No statistically significant differences were observed (ANOVA+Tukey), except for teeth with and without ligatures in both groups., Conclusions: The establishment and progression of alveolar bone loss in rats was not influenced by body weight in the present study.

Objective: Interleukin-1 (IL-1) and tumor necrosis factor (TNF) are pro-inflammatory cytokines directly related with tissue destruction in the pathogenesis of periodontitis. Inhibitory effects on IL-1 and TNF production have been attributed to the folate analog methotrexate. The purpose of this study was to evaluate the effect of methotrexate on the pathogenesis of alveolar bone loss in experimental periodontitis in rats., Methods: Ligature-induced experimental periodontitis was created in 44 Wistar rats. The animals were randomly divided into four groups and treated with methotrexate (0.1, 0.5, and 1.0 mg x kg(-1)) or saline. Morphometrical registration of alveolar bone loss was carried out after 28 days of ligature placement to determine the effect of methotrexate on the progression of experimental periodontitis., Results: Intra-group comparisons showed significantly higher alveolar bone loss mean values in maxillary sides with ligature (paired sample t-test; p<0.05). Mean alveolar bone loss was not different between groups and was independent of the dosage (range 0.63-0.67 mm, one-way ANOVA; p>0.05)., Conclusion: Although methotrexate has important cytokine-inhibitory properties, its possible use in modulating the host immune-inflammatory response in periodontal disease was not confirmed.

The purpose of this study was to compare histologic and morphometric procedures of bone height measurement. Microscopic measurements are the most frequent methods in periodontal studies with animals, but have limited capacity to identify bone levels associated with both healthy tissues and periodontal disease. Ligatures were placed in the maxillary left second molars of 10 male 60-day-old Wistar rats for 30 days. Left and right maxillary sides of 5 rats were processed for histologic analysis (H), sectioned buccolingually, and stained with HE. The maxillae of the other 5 rats were defleshed and used for morphometric analysis (M). Histometric measurements from the cementoenamel junction to the bone crest were performed. Standardized photographs were used for morphometric analysis. The t test was used for dependent or independent samples (alpha = 0.05%). Distances from cementoenamel junction to bone crest were 0.95 +/- 0.25 and 1.07 +/- 0.30 mm for H and M, respectively. Buccal measurements were 0.92 +/- 0.16 and 1.08 +/- 0.35 mm for H and M. The values obtained using H and M for areas without ligatures were 0.44 +/- 0.15 and 0.47 +/- 0.11 mm for lingual measurements and 0.23 +/- 0.08 and 0.41 +/- 0.10 mm for buccal measurements. No significant differences were found between the two methods in the detection of bone height associated with the placement of ligatures in rats.

The rat model is widely used in periodontal research and the quality of histological sections is essential. The purpose of this study was to evaluate the histological characteristics of periodontal tissues in Wistar rat maxillae, with different times of fixation and decalcified by nitric acid or formic acid (Anna Morse Solution). Fifteen rats were used. Fixation was performed for 24, 48 and 72 hours. The maxillae were hemi-sectioned and each part was decalcified either in nitric acid for 7 days or in Anna Morse solution for 35 days. Two trained and blinded examiners performed the evaluation. Fourty eight hours of fixation and decalcification with Anna Morse solution showed more clear characteristics of the epithelium-connective tissue interface and of the periodontal structures. Mean measurements between the cementum-enamel junction and the bone crest varied in the different experimental times from 176.5 (+/- 60.45) to 210.94 (+/- 39.33) pixels on the buccal aspect, and from 199.69 (+/- 38.33) to 298.55 (+/-70.81) pixels on the palatal aspect, with no statistically significant differences (ANOVA, p > 0.05). In the same fixation period, decalcification with nitric acid or Anna Morse solution did not display any statistically significant differences. It may be concluded that for a qualitative histological analysis, fixation should preferably be for 48 hours and the demineralization should be made by Anna Morse solution. For a histomorphometric analysis, the decalcification solution does not interfere in the results.

The aim of this study was to evaluate, in rats, the role of the systemic use of dexamethasone in the pathogenesis of induced alveolar bone loss. In 26 female Wistar rats, ligatures were placed around the second upper molars, and the contralateral ones served as intra-group controls. Two groups were formed. The test group received 0.5 mg/kg of dexamethasone subcutaneously every third day during thirty days. The control group received the same amount of saline solution. After thirty days, the animals were sacrificed and their maxillae were removed. Sodium hypochlorite was used to prepare the specimens, and the cementum-enamel junction was stained with 1% methylene blue. Morphometric analysis of the alveolar bone loss was performed with standardized digital photographs, and the distance between the cementum-enamel junction and the alveolar bone crest was measured with the software ImageTool 3.0. Intra-examiner calibration revealed a Pearson correlation coefficient of 0.99. Statistical analysis was performed by paired or independent samplet tests, as appropriate (alpha = 0.05). Dexamethasone increased the mean alveolar bone loss in ligature-induced periodontitis in relation to the control group (0.77 and 0.61 buccally, and 0.65 and 0.56 palatally, respectively). No significant differences were observed intergroups in the teeth without ligatures. In the animal model used here, the use of dexamethasone increased the progression of ligature-induced alveolar bone loss.