Subgingival biofilm microbiome in individuals with asthma and periodontitis: Metagenomic analysis.

OBJECTIVE: This observational study aimed to explore the metagenomics of subgingival biofilms in individuals with varying degrees of asthma, from severe to none, to elucidate the association between the subgingival microbiome and asthma. MATERIALS AND METHODS: Subgingival biofilm samples were collected from thirty participants at the Asthma Control Program Outpatient Clinic in Bahia (ProAR). These samples were categorized into six groups based on the severity of asthma and the presence or absence of periodontitis. We employed next-generation sequencing (Illumina MiSeq), targeting the 16S rRNA gene, to characterize the microbial communities present. Our analysis included descriptive statistics and sequencing data, evaluated using multivariate statistical methods such as the Shannon index, principal coordinate analysis, and the Bray-Curtis dissimilarity. RESULTS: Our findings indicate a higher prevalence of periodontally detrimental bacterial genera in individuals with severe asthma and periodontitis. Additionally, individuals with asthma, but without periodontitis, exhibited a tendency toward dysbiosis, particularly in cases of severe asthma. CONCLUSION: This research provides new insights into the composition of the subgingival microbiome in individuals with varying severities of asthma and periodontitis. The genera identified in this study underscore the need for further investigations to build upon these findings.

Exploring dysregulated immune response genes and endothelial dysfunction biomarkers as predictors of severe COVID-19.

Identifying individuals and factors associated with severe cases of COVID-19 is crucial as the pandemic continues to spread globally. Effective biomarkers for predicting severe cases are essential for optimizing clinical management, therapy, and preventing unfavorable outcomes. This exploratory observational study aimed to investigate the expression of dysregulated immune response genes (ARG1, NOS2, ITGA4, and SELPLG) in total leukocytes, plasmatic levels of P-selectin and PSGL-1, and their clinical associations in patients with mild and severe COVID-19. Data from 117 confirmed COVID-19 patients (severe = 58, mild = 59) were collected upon admission. Gene expression was measured using RT-qPCR, and plasma protein levels assessed with ELISA assay. The severe COVID-19 patient group had a higher median age of 62.0 (p = 0.0001), a higher proportion of black individuals (86.2%, p < 0.0001), and more males (65.5%, p = 0.007). The neutrophil-lymphocyte ratio (NLR) and platelet-lymphocyte ratio (PLR) were significantly higher in the severe COVID-19 patient group (p < 0.0001), indicating ongoing systemic inflammation. Severe COVID-19 patients also exhibited increased expression of ARG1 (p < 0.05) and SELPLG (p < 0.0001) genes, as well as higher concentrations of soluble P-selectin (p < 0.005) and PSGL-1 (p < 0.05) proteins. Multivariate analysis revealed that NLR, PLR, the expression of SELPLG and sPSGL-1 were independent predictors of COVID-19 severity. In conclusion, this study suggests that biomarkers of endothelial dysfunction and dysregulated leukocyte responses are associated with COVID-19 severity, serving as promising predictive tools for optimizing clinical management and patient monitoring.

Hemophore-like proteins produced by periodontopathogens are recognized by the host immune system and react differentially with IgG antibodies.

Aims: Hemophore-like proteins sequester heme from host hemoproteins. We aimed to determine whether the host immune system can recognize not only Porphyromonas gingivalis HmuY but also its homologs expressed by other periodontopathogens, and how periodontitis influences the production of respective antibodies. Methods: The reactivity of total bacterial antigens and purified proteins with serum IgG antibodies of 18 individuals with periodontitis and 17 individuals without periodontitis was examined by enzyme-linked immunosorbent assay (ELISA). To compare IgG reactivity between groups with and without periodontitis and within the various dilutions of sera, statistical analysis was performed using the Mann-Whitney U-test and two-way ANOVA test with the post-hoc Bonferroni test. Results: Individuals with periodontitis produced IgG antibodies reacting more strongly not only with total P. gingivalis antigens (P = 0.0002; 1:400) and P. gingivalis HmuY (P = 0.0016; 1:100) but also with Prevotella intermedia PinA (P = 0.0059; 1:100), and with low efficiency with P. intermedia PinO (P = 0.0021; 1:100). No increase in the reactivity of IgG antibodies with Tannerella forsythia Tfo and P. gingivalis HusA was found in individuals with periodontitis. Conclusions: Although hemophore-like proteins are structurally related, they are differentially recognized by the host immune system. Our findings point to specific antigens, mainly P. gingivalis HmuY and P. intermedia PinA, whose immunoreactivity could be further investigated to develop markers of periodontitis.

Single nucleotide variants in the IL33 and IL1RL1 (ST2) genes are associated with periodontitis and with Aggregatibacter actinomycetemcomitans in the dental plaque biofilm: A putative role in understanding the host immune response in periodontitis.

The Interleukin (IL)-33 is important in several inflammatory diseases and its cellular receptor is the Interleukin 1 receptor-like 1 (IL1RL1), also called suppression of tumorigenicity 2 ligand (ST2L). This study investigated associations between single nucleotide variants (SNVs) in the IL33 gene and in the IL1RL1 (ST2) gene with periodontitis. Additionally, aimed to determine the role of Aggregatibacter actinomycetemcomitans (Aa) relative amount in the subgingival biofilm in these associations. A cross-sectional study was carried out with 506 individuals that answered a structured questionnaire used to collect their health status, socioeconomic-demographic, and behavioral characteristics. Periodontal examination was performed to determine the presence and severity of periodontitis, and subgingival biofilm samples were collected to quantify the relative amount of Aa by real time polymerase chain reaction. Human genomic DNA was extracted from whole blood cells and SNV genotyping was performed. Logistic regression estimated the association measurements, odds ratio (OR), and 95% confidence interval (95%CI), between the IL33 and ST2 genes with periodontitis, and subgroup analyses assessed the relative amount of Aa in these associations. 23% of individuals had periodontitis. Adjusted measurements showed a statistically significant inverse association between two SNVs of the ST2; rs148548829 (C allele) and rs10206753 (G allele). These two alleles together with a third SNV, the rs11693204 (A allele), were inversely associated with moderate periodontitis. One SNV of the IL33 gene also showed a statistically significant inverse association with moderate periodontitis. Nine SNVs of the ST2 gene were inversely associated with the relative amount of Aa. In the high Aa subgroup, there was a direct association between 11 SNVs of the ST2 gene and moderate periodontitis and two SNVs of the ST2 gene and severe periodontitis, and eight SNVs of the ST2 gene and periodontitis. These exploratory findings of genetic variants in IL-33/ST2 axis support the concept that the different tissue responses among individuals with periodontitis may be modulated by the host's genetics, influencing the physiopathology of the disease.

Periodontitis and its higher levels of severity are associated with the triglyceride/high density lipoprotein cholesterol ratio.

BACKGROUND: Periodontitis and the Triglyceride/High Density Lipoprotein Cholesterol (TG/HDL-C) ratio have both been associated with cardiovascular disease, metabolic syndrome, and obesity. Additionally, the ratio is a possible substitute for predicting insulin resistance. This study investigated the association between periodontitis, its severity levels (exposures), and the TG/HDL-C ratio (outcome). METHODS: A cross-sectional study of public health service users in Brazil considered socioeconomic-demographic characteristics, lifestyle behavior, and general and oral health conditions. Anthropometric measurements and blood pressure were also measured. Systemic biomarker data were obtained, as well as assessment of periodontal diagnosis and its severity. The TG/HDL-C ratio was calculated using the serum triglyceride level over HDL cholesterol and the cut-off point, TG/HDL-C ≥2.3 serving as the cutoff indicting dyslipidemia. Logistic and linear regressions were used to statistically analyze the data. RESULTS: A total of 1011 participants were included, with 84.17% having periodontitis and 49.85% having a TG/HDL-C ratio ≥2.3. For individuals with periodontitis, the odds of TG/HDL-C ratio ≥2.3 were 1.47 times greater than in those without periodontitis (ORAdjusted  = 1.47, 95% CI: 1.02-2.14). Similar results were found for those with moderate and severe periodontitis, with a slight increase in the measurement magnitude with disease severity. CONCLUSION: A positive relationship between periodontitis and the TG/HDL-C ratio ≥2.3 was found, suggesting a possible association with periodontal disease severity.

Moderate and severe periodontitis are positively associated with metabolic syndrome.

OBJECTIVE: This study investigated the association between periodontitis severity (exposure) and metabolic syndrome (MetS - outcome), using two criteria for diagnosis of the outcome, since this relationship remains unexplored. MATERIALS AND METHODS: A case-control study was conducted with 870 individuals: 408 with first MetS diagnosis (cases) and 462 without MetS (controls). Participants' general information was obtained using a questionnaire and laboratory data was collected from medical records. Periodontitis severity criteria followed the Center for Disease Control and Prevention: none, mild, moderate, and severe. Odds ratios (OR) and 95% confidence intervals (95% CI) were determined by logistic regression analysis. RESULTS: Findings showed a positive association between moderate and severe periodontitis and MetS: ORadjusted = 1.64 (95% CI: 1.01 to 2.68) and ORadjusted = 1.94 (95% CI: 1.19 to 3.16), respectively, after adjustment for age, sex, schooling level, smoking habit, and cardiovascular disease. The adjusted measurements showed that among individuals with moderate or severe periodontitis, the probability of having MetS was around two times greater than among those without periodontitis, and that the chance was greater among participants with severe periodontitis than those with moderate periodontitis. CONCLUSION: An association between the severity of periodontal status and MetS was found, suggesting a possible relationship between the two diseases. CLINICAL RELEVANCE: MetS influences the etiology of cardiovascular diseases, one of the leading causes of mortality worldwide. The findings suggest that the greater the severity of periodontitis, the greater is the association magnitude with MetS. The health professional needs to recognize that the importance of periodontal disease may play in MetS.

Severe and moderate periodontitis are associated with acute myocardial infarction.

BACKGROUND: An association between periodontitis and cardiovascular disease is now well documented; however, the effect of periodontitis severity levels on this outcome, specifically on acute myocardial infarction (AMI), remains unexplored. This study investigated the association between levels of periodontitis severity (exposure) and AMI (outcome). METHODS: This case-control study, matched by sex and age, was conducted with 621 participants, with 207 individuals treated in the emergency department of Santa Izabel and Ana Nery Hospitals in Salvador, Bahia, Brazil, diagnosed with a first AMI event, and compared to 414 individuals without a diagnosis of AMI. Levels of periodontitis severity followed two criteria: (1) Center for Disease Prevention and Control and American Academy of Periodontology; (2) Gomes-Filho et al. (2018) using criteria that also evaluated bleeding upon probing. Conditional logistic regression analysis was performed and odds ratios (ORs) and their 95% confidence intervals (CIs) were obtained. RESULTS: The adjusted association measurements showed a positive association between both severe (ORadjusted ranged from 2.21 to 3.92; 95% CI ranged from 1.03 to 10.05) and moderate periodontitis (ORadjusted ranged from 1.96 to 2.51; 95% CI ranged from 1.02 to 6.19), and AMI, for both periodontitis diagnostic criteria. It demonstrated that among those with moderate and severe periodontitis, the chance of having AMI was approximately two to four times greater than among those without periodontitis. CONCLUSION: The findings demonstrate that there is an association between the severity of the periodontal condition and AMI, suggesting a possible relationship among the levels of periodontitis severity and the cardiovascular condition.

Is there association between stress and periodontitis?

OBJECTIVE: This study estimated the association between stress and periodontitis. MATERIALS AND METHODS: A cross-sectional study was conducted with a sample of 621 individuals. Information about individuals was obtained through a questionnaire. Stress was evaluated using the Perceived Stress Scale. The diagnosis of periodontitis was based on a complete periodontal examination including clinical attachment level, probing depth, and bleeding on probing. Prevalence ratios (PR), crude and adjusted, and their respective 95% confidence intervals (95%CI) were estimated by Poisson regression analysis. RESULTS: In the final sample, 48.47% (301) of the individuals were classified as having stress, of which, 23.92% (72) had the diagnosis of periodontitis. Association measurements between stress and probing depth ≥ 4 mm (PRadjusted = 1.28, 95%CI [1.04 to 1.58]), stress and clinical attachment level ≥ 5 mm (PRadjusted = 1.15, 95%CI [1.01 to 1.31]), and stress and periodontitis (PRadjusted = 1.36, 95%CI [1.01 to 1.83]) showed that the frequency of these outcomes among those exposed to stress was 15-36% higher than those without the condition of stress, after adjustment for age, sex, schooling level, current smoking habit, pulmonary disease, and body mass index. CONCLUSIONS: The findings showed positive association between exposure to stress and the presence of periodontitis, reaffirming the need to prevent and control stress. CLINICAL RELEVANCE: Although there are limitations in this study, the results showed that an association exists between stress and periodontitis, signaling the necessity of a multidisciplinary attention when considering the psychological status in the management of oral and general health conditions of the individual.

Prevotella intermedia and periodontitis are associated with severe asthma.

BACKGROUND: Periodontitis, an inflammatory disease of multibacterial etiology that affects the protective and supporting tissues surrounding teeth, can influence the course of respiratory diseases, such as asthma, due to epithelial alterations arising from inflammatory and immunological processes, bronchial remodeling, or by the aspiration of pathogenic colonizers found in periodontal pockets. This study evaluated the levels of periodontal pathogens Prevotella intermedia, Porphyromonas gingivalis, Treponema denticola, Tannerella forsythia, and Aggregatibacter actinomycetemcomitans in the subgingival biofilm of individuals with and without severe asthma. METHODS: A case-control study enrolling 457 individuals (220 with asthma and 237 without asthma) was conducted at the Program for Control of Asthma in Bahia (ProAR) Clinic located in Salvador, Bahia, Brazil. A structured questionnaire was used to obtain data on sociodemographic, health status, and lifestyle habits. A clinical periodontal assessment was performed, including bleeding on probing, probing depth, and clinical attachment level. Subgingival biofilm was collected at the deepest site of each sextant, and bacterial DNA was extracted. Quantitative real-time PCR analysis was performed to detect and relatively quantify periodontopathogens in the biofilm. RESULTS: Statistically significant positive associations were found between periodontitis and severe asthma, (odds ratio [OR]adjusted] : 4.00; 95% confidence interval [CI]: 2.26 to 7.10). High levels of P. intermedia were found in association with the presence of severe asthma (ORadjusted : 2.64; 95% CI: 1.62 to 4.39; P < 0.01). CONCLUSIONS: The present results suggest that periodontitis and P. intermedia are associated with severe asthma. However, the functional consequences of this dysbiosis upon asthma susceptibility and its phenotypes remain unclear.

Common mental disorder is associated with periodontitis.

OBJECTIVES: This research evaluated the association between exposure to common mental disorder (CMD) and the presence of periodontitis. BACKGROUND: Common mental disorder is characterized by the presence of irritation, fatigue, insomnia, forgetfulness, decreased ability to concentrate, anxiety, and depression. It has been associated with several diseases; however, there are few studies that have associated it with periodontitis. METHODS: This cross-sectional study was carried out with 621 individuals. Data collection involved the application of a general questionnaire and the self-reporting questionnaire for diagnosis of CMD. The diagnosis of periodontitis involved a full mouth periodontal examination using: clinical attachment level, probing depth, and bleeding on probing. Prevalence ratios and 95% confidence intervals between CMD (exposure) and periodontitis (outcome) were obtained. RESULTS: In the final sample, 38.16% (237) of the individuals were classified with CMD. Among these, 28.27% (67) had periodontitis. Association measurements showed that the occurrence of periodontitis among those exposed to CMD is approximately 50% higher than in those without this mental condition, with statistical significance, after adjustment for age, sex, family income, current smoking habit, alcohol beverage consumption, and cardiovascular disease (PRadjusted  = 1.54, 95% CI: [1.13 to 2.10]). CONCLUSIONS: The findings showed a positive association between exposure to CMD and periodontitis, revealing the importance of broadening public actions targeting mental health, which seems to be related to oral health, mainly due to the high frequency of the diseases in the studied sample.

Apoptosis Transcriptional Profile Induced by Porphyromonas gingivalis HmuY.

This study aimed at evaluating the transcriptional profile of apoptosis-related genes after in vitro stimulation of peripheral blood mononuclear cells (PBMCs) derived from individuals with periodontitis (P) and healthy nonperiodontitis (NP) control subjects with P. gingivalis HmuY protein. PBMCs from the P and NP groups were stimulated with HmuY P. gingivalis protein, and the expression of genes related to apoptosis was assessed by custom real-time polymerase chain reaction array (Custom RT2 PCR Array). Compared with the NP group, the P group showed low relative levels of apoptosis-related gene expression, downregulated for FAS, FAS ligand, TNFSF10 (TRAIL), BAK1, CASP9, and APAF1 after P. gingivalis HmuY protein stimulation. Furthermore, the P group exhibited low levels of relative gene expression, downregulated for CASP7 when the cells were not stimulated. Our data suggest that P. gingivalis HmuY protein might participate differently in the modulation of the intrinsic and extrinsic apoptosis pathways.

Production of interferon-gamma, interleukin-6, and interleukin-1ß by human peripheral blood mononuclear cells stimulated with novel lys-gingipain synthetic peptides.

BACKGROUND: Periodontitis is a progressive inflammatory process, and its pathogenesis is related to the presence of a dysbiotic subgingival biofilm that elicits the immune response. Porphyromonas gingivalis is a keystone pathogen, and its Lys-gingipain (Kgp) virulence factor is involved in the pathogen-host interaction through the production of cytokines by host cells, but the specific mechanisms of this interaction have not been elucidated. The present study evaluated the in vitro production of interferon-gamma (IFN-γ), interleukin (IL)-6, and IL-1ß cytokines in response to antigenic stimulation of peripheral blood mononuclear cells (PBMCs) with novel Kgp synthetic peptides. METHODS: Our previous in silico study predicted 16 immunogenic peptides from Kgp protein. Nine peptides derived from different regions of the protein were chemically synthesized. The synthetic peptides Kgp12, 17, and 18 were selected based on the immunoglobulin G immunoreactivity in the serum of patients with periodontitis (P) and individuals without periodontitis (WP), and they were used in in vitro stimulation of PBMC derived from groups P and WP. Enzyme-linked immunosorbent assay and microsphere-based flow cytometric assay were used to verify the levels of the cytokines produced in PBMC cultures after 48 hours. RESULTS: Kgp12, 17, and 18 peptides induced lower production of IFN-γ. Kgp12 induced higher levels of IFN-γ in WP than in P individuals. Kgp12 induced higher production of IL-6 and IL-1ß compared with the other stimuli. CONCLUSION: The novel Kgp synthetic peptides tested herein are immunogenic peptides (epitopes) since they induced the production of cytokines by PBMC and therefore may be useful tools in evaluating the pathogen-host interaction.

Association between osteoporosis treatment and severe periodontitis in postmenopausal women.

OBJECTIVE: To estimate the association between osteoporosis treatment and severe periodontitis in postmenopausal women. METHODS: This cross-sectional study comprised of 492 postmenopausal women, 113 women in osteoporosis treatment, and 379 not treated. Osteoporosis treatment consisted of systemic estrogen alone, or estrogen plus progestin, and calcium and vitamin D supplements, for at least 6 months. Severe periodontitis was defined as at least two interproximal tooth sites with clinical attachment loss of at least 6 mm, and at least one interproximal site with probing depth of at least 5 mm; and dental caries experience was measured using the decayed, missing, and filled teeth (DMFT) index. Analysis included descriptive statistics and Poisson multivariate analysis with robust variance. RESULTS: Women receiving osteoporosis treatment had less periodontal probing depth, less clinical attachment loss, and less gingival bleeding than women not receiving treatment for osteoporosis (P ≤ 0.05). In the osteoporosis treatment group, the estimated mean DMFT index score was approximately 20, the most frequent component being the number of missing teeth, and in the nontreated group, the DMFT index was approximately 19. The prevalence of severe periodontitis was 44% lower in the osteoporosis treatment group than in the nontreatment group. The prevalence ratioadjusted was 0.56, 95% confidence interval was 0.31 to 0.99 (P = 0.05), after adjustments for smoking, age, family income, and visit to the dentist. CONCLUSIONS: The results suggest that women treated with estrogen for postmenopausal osteoporosis have a lower prevalence of severe periodontitis than women not receiving treatment.

Immune response of macrophages induced by Porphyromonas gingivalis requires HmuY protein.

The main etiologic agent and a key pathogen responsible for initiation and progression of chronic periodontitis is Porphyromonas gingivalis. We examined the role of P. gingivalis, with particular interest to HmuY protein, in expression of genes involved in Toll-like receptor (TLR)-induced signaling pathways using cell-based infection model. U937 and THP-1 cells differentiated toward macrophages by PMA treatment responded to P. gingivalis-caused infection in slightly different gene expression pattern, mainly by higher expression of genes encoding NF-κB, TLR7, TLR2, TLR8, pro-inflammatory cytokines (IL-1ß, IL-6, TNFα), anti-inflammatory cytokine (IL-10), and chemokines (CCL3L1, CCL4, CXCL10, CXCL11, PTX3). P. gingivalis lacking functional hmuY gene stimulates immune response of macrophages, albeit in a different manner as compared with the wild-type strain, mainly by lower expression of genes encoding NF-κB, IL-1ß, IL-10, CD80, PTX3, and CCL31L. The purified HmuY protein alone induced expression of genes encoding IL-6, IL-10, TNFα, CCL3L1, and CCL4. We conclude that macrophages respond to P. gingivalis infection mostly by TLR7-induced pathway(s). Moreover, P. gingivalis HmuY is one of important virulence factors, which allows P. gingivalis for in vivo growth in the heme-limited host environment, resulting in efficient immune response of macrophages.

Relationship Among Mothers' Glycemic Level, Periodontitis, and Birth Weight.

BACKGROUND: The aim of this study is to determine the influence of glycemic level on the relationship between periodontitis and low birth weight (LBW). METHODS: A case-control study was conducted with 372 females divided into cases (109 mothers of newborns with birth weight < 2,500 g) and controls (263 mothers of newborns with birth weight ≥ 2,500 g). The birth weight of children was obtained from medical records, whereas information on sociodemographic, lifestyle, and health characteristics of the participants was obtained through an interview. Glycated hemoglobin (HbA1c) levels were measured, and probing depth, clinical attachment levels, and bleeding on probing were used to determine the periodontal status. Results were analyzed using logistic regression. RESULTS: The likelihood of having children with LBW among the mothers with periodontitis was six times greater than that observed among mothers without periodontitis (adjusted odds ratio [OR adjusted] = 6.02, 95% confidence interval [CI] = 2.47 to 15.17), even after adjustment. There was also a strong, statistically significant relationship between periodontitis and LBW in both the normal glycemic-level group (HbA1c levels < 5.6%, unadjusted odds ratio [OR unadjusted] = 8.30, 95% CI = 3.56 to 19.35) and the high glycemic-level group (HbA1c levels ≥ 5.6% and < 6.5%, OR unadjusted = 5.73, 95% CI = 1.75 to 18.70). After adjustment for confounders, the magnitude of the association continued to be strong in the normal glycemic-level group (OR adjusted = 7.59, 95% CI = 2.7 to 24.28), an increase of 25% when compared to the main association measurement. In those with high glycemic levels (OR adjusted = 4.03, 95% CI = 0.81 to 19.96), the OR decreased almost 50%, and the association lost statistical significance. CONCLUSION: Periodontitis and glycemic levels appeared to have opposing influences on birth weight, with periodontitis being associated with LBW and the magnitude of the association being altered depending on maternal blood glucose level.

Porphyromonas gingivalis HmuY stimulates expression of Bcl-2 and Fas by human CD3+ T cells.

BACKGROUND: Apoptosis is a highly controlled process of cell death that can be induced by periodontopathogens. The present study aimed to investigate the expression of Fas and Bcl-2 proteins by CD3+ T cells in vitro under stimulation by total Porphyromonas gingivalis antigens and purified recombinant P. gingivalis HmuY protein. RESULTS: CD3+ T cells derived from CP patients and stimulated with HmuY expressed higher levels of Bcl-2 compared to identical cells stimulated with P. gingivalis crude extract or cells derived from NP control subjects (p = 0.043). CONCLUSION: The authors hypothesize that P. gingivalis HmuY plays a role in the pathogenesis of chronic periodontitis, possibly by reducing or delaying apoptosis in T cells through a pathway involving the Bcl-2 protein.

Effect of osteoporosis on periodontal therapy among post-menopausal women.

OBJECTIVE: This intervention study aimed to investigate the effect of osteoporosis on periodontal condition among 48 post-menopausal women undergoing periodontal therapy. MATERIAL AND METHODS: The experimental group, which underwent non-surgical periodontal therapy, was composed of 16 women with periodontitis to be treated, and the control group was formed by 32 women without periodontitis. Oral condition was assessed on three occasions: at the start of the treatment (first examination), 1 month (first re-examination) and 4 months after the end of the therapy (second re-examination). In the second re-examination, recurrence of periodontal disease was evaluated by comparing the clinical measurements obtained pre- and post-treatment. The diagnosis of osteoporosis was made by investigating densitometry reports obtained previously. Descriptive analysis, analysis of variance and the Bonferroni post hoc test were applied to the data gathered, with statistical significance level of 5%. RESULTS: The frequency of periodontitis was 50% in the treated group and 25% in the group without periodontitis. In both groups, this recurrence was greater in subjects with osteoporosis (37.5 and 18.75%, respectively) than in the individuals without osteoporosis (12.5 and 6.25%, respectively). CONCLUSIONS: The preliminary results indicate that osteoporosis possibly has an influence on periodontal condition among individuals undergoing non-surgical periodontal treatment.

Women with low bone mineral density and dental panoramic radiography.

OBJECTIVE: The aim of this study was to investigate whether some mandibular measurements on panoramic radiographs are associated with low bone mineral density in postmenopausal women. METHODS: A sample of 122 panoramic dental radiographs and bone density tests from women 50 years or older were examined. Bone mineral density was measured in the lumbar spine and proximal femur regions through dual-energy x-ray absorptiometry. The mandibular cortical bone thickness below the mental foramen, mandibular alveolar bone resorption, and panoramic mandibular index were measured. RESULTS: The mandibular cortical thickness and mandibular alveolar bone resorption showed the highest specificity (lumbar spine: 89.8% vs 73.5%, proximal femur: 83.6% vs 71.2%, respectively). The panoramic mandibular index demonstrated the highest sensitivity (lumbar spine: 43.8%; proximal femur: 40.8%). The association between the mandibular cortical thickness and bone mineral density was statistically significant even after adjustment for hormonal treatment, smoking, age at menopause, and body mass index (P = 0.04). CONCLUSIONS: It is suggested that panoramic radiography may be useful for confirming individuals who present with low bone mineral density.

Porphyromonas gingivalis antigens differently participate in the proliferation and cell death of human PBMC.

OBJECTIVE: Modulation of cell-mediated immunity by microorganisms in periodontal diseases has been widely studied; however, the proliferative activity and/or programmed death of mononuclear cells under periodontopathogenic stimuli are not yet well understood. The aim of this study was to investigate in vitro proliferation and death of peripheral blood mononuclear cells (PBMC) upon stimulation with Porphyromonas gingivalis (Pg) antigens. DESIGN: In 19 patients with chronic periodontitis (CP) and 16 controls without periodontitis (NP) the following clinical parameters were evaluated: bleeding on probing, probing depth, and clinical attachment level. PBMC were cultured under Pg stimuli and apoptosis/necrosis and proliferation assays were carried out for 18 and 48 h, respectively. Fluorescence of labelled cells was determined using flow cytometry. RESULTS: PBMC of CP and NP subjects exhibited a lower proliferative response to Pg LPS (p<0.05) and HmuY protein (p<0.001) compared with non-stimulated cells. Early apoptosis was induced by Pg LPS (p<0.01) and Pg extract (p<0.05), whilst all antigens induced late apoptosis (Pg LPS: p<0.001; Pg extract: p<0.001; HmuY: p<0.01) and necrosis (Pg LPS: p<0.01; Pg extract: p<0.001; HmuY: p<0.001). Pg LPS induced higher late apoptosis than HmuY (p<0.05). Only Pg LPS-induced necrosis tended to be higher in CP compared with NP. CONCLUSIONS: The inhibitory effect of cell proliferation caused by Pg LPS and HmuY protein is not observed when these antigens comprise Pg extract. Despite induced apoptosis, some still unknown mechanism determines the inflammatory outcome in cell death stimulated by HmuY.

Serum antibody levels against Porphyromonas gingivalis extract and its chromatographic fraction in chronic and aggressive periodontitis.

UNLABELLED: Periodontitis is an inflammatory oral disease caused by multifactorial intrinsic and extrinsic agents, including Gram-negative bacteria such as Porphyromonas gingivalis. OBJECTIVE: To evaluate if there is difference in the serum levels of IgA, IgG and IgG subclasses reactive to Porphyromonas gingivalis in subjects with different periodontal conditions. METHODS: The study included 89 patients divided into four groups: 29 subjects with moderate or severe chronic periodontitis (CP), 12 with aggressive periodontitis (AP), 22 with gingivitis or mild periodontitis (GP), and 26 healthy controls (HC). Humoral response was assayed by enzyme-linked immunosorbent assay (ELISA) to verify serum levels of IgG, IgG1, IgG2, IgG3, IgG4 and IgA serum levels reacting to crude P. gingivalis ATCC 33277 sonicate extract and fraction IV, an enrichment of the immunoreactive bands of the crude extract obtained by chromatography. RESULTS: IgA, IgG (p < 0.01), IgG2, IgG3 and IgG4 serum level reactions to fraction IV were higher in the CP group compared with the healthy control. The CP group had higher levels of IgG and IgG4 to both antigens than the GP group, and higher levels of IgG and IgG4 to sonicate extract than the AP group. There were statistically significant differences in serum levels of IgG to both antigens (p < 0.01), IgG2 to fraction IV (p < 0.01), IgG3 to fraction IV (p < 0.05) and IgG4 to both antigens (p < 0.05) between AP and HC groups. IgG1 titers to sonicate extract were significantly higher (p < 0.05) in the GP group in comparison to the AP group. CONCLUSIONS: The findings of this study suggest that there are differences in the serum levels of IgA, IgG and IgG subclasses in patients with different periodontal conditions.