Effect of tumor necrosis factor alpha (TNF-α) -308 and -1031 gene polymorphisms on periodontitis among Saudi subjects

ObjectivesPeriodontitis is an infectious disorder that leads to irreversible loss of the surrounding attachment and bone destruction. Genetic polymorphism of cytokines has been suggested to play a role in periodontitis. This case-control study aimed to investigate the relationship between periodontitis and two single nucleotide polymorphisms (SNPs): rs1800629 (-308 G/A) and rs1799964 (-1031 T/C), in the TNF-α gene promoter area.Materials and methodsPeripheral blood was used to prepare genomic DNA from 60 subjects with stage II to stage III periodontitis, as along with 65 control subjects. Polymerase chain reaction and restriction endonuclease digestion were used to genotype TNF-α SNPs.ResultsThe distribution of both genotypes and alleles of TNF-α (-308 G/A) polymorphism did not vary between periodontitis subjects and the controls (P > 0.05). However, the CT genotype and C allele of the TNF-α (-1031 T/C) polymorphism were observed more frequently in the periodontitis subjects than in the controls, while the TT genotype and the T allele were more predominant in the control subjects than in the periodontitis patients (OR: 3.149; 95% CI: 1.494–6.639; P = 0.002 and OR: 2.933; 95% CI: 1.413–6.090; P = 0.003, sequentially).ConclusionThe TNF-α (-308 G/A) polymorphism potentially has no correlation with periodontitis susceptibility, whereas the TNF-α (-1031) CT genotype and C allele might be related to periodontitis among Saudi subjects.     

Quantitative Assessment of the Associations Between Interleukin‐8 Polymorphisms and Periodontitis Susceptibility

Background: This review assesses the associations of interleukin‐8 gene (IL‐8) ?251A/T (rs4073) and ?845T/C (rs2227532) polymorphisms with susceptibility to periodontitis. Methods: Several electronic databases were searched for eligible articles. Twelve studies involving 2,233 cases and 2,655 controls were retrieved and analyzed. Odds ratios (ORs) along with 95% confidence intervals (CIs) were calculated to assess the strength of relationship between the IL‐8 polymorphisms and periodontitis risk. Results: No significant association was found for IL‐8 ?251A/T polymorphism with periodontitis in the overall analysis and stratification by periodontitis type and smoking status. Subgroup analysis by ethnicity revealed that ?251A/T T allele and TT genotype were associated with decreased risk of periodontitis in a Brazilian mixed population (T allele versus A allele: OR 0.80, 95% CI 0.68 to 0.94, P_{heterogeneity} = 0.30; TT versus AA: OR 0.65, 95% CI 0.46 to 0.93, P_{heterogeneity} = 0.39; TT versus AA/AT: OR 0.58, 95% CI 0.35 to 0.98, P_{heterogeneity} = 0.01). In addition, ?251A/T T allele was associated with increased periodontitis risk in Asians. Pooled estimates showed that the ?845T/C polymorphism was associated with periodontitis susceptibility in overall analysis and the chronic periodontitis subgroup. In addition, marginal associations were observed between ?845T/C polymorphism and periodontitis in a Brazilian mixed population. Moreover, this association was also confirmed to be significant in Brazilian non‐smokers. Conclusion: This meta‐analysis indicated that both IL‐8 ?251A/T and ?845T/C polymorphisms may be involved in the development of periodontitis in a Brazilian mixed population, whereas the ?251A/T allele T appeared to be a risk factor for periodontitis in Asians.     

Effect of tumor necrosis factor alpha (TNF-α) -308 and -1031 gene polymorphisms on periodontitis among Saudi subjects

ObjectivesPeriodontitis is an infectious disorder that leads to irreversible loss of the surrounding attachment and bone destruction. Genetic polymorphism of cytokines has been suggested to play a role in periodontitis. This case-control study aimed to investigate the relationship between periodontitis and two single nucleotide polymorphisms (SNPs): rs1800629 (-308 G/A) and rs1799964 (-1031 T/C), in the TNF-α gene promoter area.Materials and methodsPeripheral blood was used to prepare genomic DNA from 60 subjects with stage II to stage III periodontitis, as along with 65 control subjects. Polymerase chain reaction and restriction endonuclease digestion were used to genotype TNF-α SNPs.ResultsThe distribution of both genotypes and alleles of TNF-α (-308 G/A) polymorphism did not vary between periodontitis subjects and the controls (P > 0.05). However, the CT genotype and C allele of the TNF-α (-1031 T/C) polymorphism were observed more frequently in the periodontitis subjects than in the controls, while the TT genotype and the T allele were more predominant in the control subjects than in the periodontitis patients (OR: 3.149; 95% CI: 1.494–6.639; P = 0.002 and OR: 2.933; 95% CI: 1.413–6.090; P = 0.003, sequentially).ConclusionThe TNF-α (-308 G/A) polymorphism potentially has no correlation with periodontitis susceptibility, whereas the TNF-α (-1031) CT genotype and C allele might be related to periodontitis among Saudi subjects.     

Interleukin-6 gene -174G>C promoter polymorphism reduces the risk of periodontitis in Brazilian populations: A meta-analysis

IntroductionPeriodontitis is a multifactorial host-mediated oral disease caused by microbes. Previous studies suggested that interleukin-6 (IL-6) gene promoter polymorphism (-174G > C) are associated with the risk of periodontitis, although the results were inconclusive. This study investigated the association between IL-6 -174G > C polymorphism and susceptibility to periodontitis.MethodA comprehensive search was conducted in PubMed, EMBASE, Web of Science, and Google Scholar databases to retrieve relevant studies. Pooled odds ratios (ORs) and 95% confidence intervals (CIs) were calculated to assess the strength of the association between 174G > C polymorphism and the risk of periodontitis. Cochrane Q and I² statistics were used to measure heterogeneity between studies. Publication bias was estimated using Begg's funnel plots and Egger's test.ResultsOur results showed significant differences in the allelic (C vs. G: OR = 0.82, CI = 0.65–1.03), recessive (CC vs. GC + GG: OR = 0.69, CI = 0.42–1.13), and dominant (GC + CC vs. GG: OR = 0.85, CI = 0.63–1.13) genetic models of the IL6 -174G > C polymorphism and risk of periodontitis. Further, subgroup analysis showed decreased susceptibility to periodontitis associated with IL6 -174 G > C in a Brazilian population (C vs. G: OR = 0.60, CI = 0.41–0.88; GC + CC vs. GG: OR = 0.57, CI = 0.42–0.78) but not in Asian or Caucasian populations.ConclusionThe findings of this study revealed that the IL6 -174 “C" allele is protective against periodontitis in the Brazilian population.     

Association Between Interleukin‐4 Gene −590 C/T, −33 C/T,and 70‐Base‐Pair Polymorphisms and Periodontitis Susceptibility: A Meta‐Analysis

Background: Several studies have investigated the association between interleukin (IL)‐4 gene ?590 C/T, ?33 C/T, or 70–base pair (70‐bp) polymorphisms and periodontitis susceptibility but with conflicting results. Hence, a meta‐analysis was conducted to explore whether these polymorphisms are associated with periodontitis susceptibility. Methods: A comprehensive literature search was conducted of PubMed, Embase, Scopus, ScienceDirect, and Web of Science up to April 5, 2014. After the eligible studies were identified, data were extracted and quality‐assessed before performing the meta‐analysis. Results: The meta‐analysis included 23 eligible case‐control studies from 11 articles involving 12 studies of the ?590 C/T polymorphism (1,220 cases and 2,039 controls), five of the ?33 C/T polymorphism (715 cases and 967 controls), and four of the 70‐bp polymorphism (426 cases and 506 controls). The meta‐analysis showed that none of these IL‐4 gene polymorphisms were significantly associated with periodontitis susceptibility in all study participants. However, subgroup analysis showed that the IL‐4 ?590 T allele (odds ratio [OR] = 1.2, 95% confidence interval [CI] = 1.02 to 1.42, P = 0.03) and TT genotype (OR = 1.68, 95% CI = 1.05 to 2.67, P = 0.03) were associated with periodontitis in whites. Conclusions: Based on current evidence, the IL‐4 ?33 C/T and 70‐bp polymorphisms were not associated with an increased risk of periodontitis. However, the IL‐4 ?590 T allele and TT genotype were associated with increased risk of periodontitis in whites.     

The association between interleukin polymorphism and recurrent aphthous stomatitis: A meta-analysis

ObjectiveTo assess the association between interleukin gene polymorphism and recurrent aphthous stomatitis (RAS).DesignsTwo electronic databases, PubMed and Embase, were utilized to assemble potentially relevant studies meeting the inclusion criteria. A meta-analysis was conducted using Revman 5.3 software (London, UK), and the pooled odds ratio (OR) and 95% confidence interval (CI) were then used to evaluate the strength of the relationship between the gene polymorphisms of IL-1beta(−511C/T), IL-1beta(+3954C/T), IL-6(−174G/C) and IL-10(−1082G/A) and the risk of RAS.ResultsTen studies were included in the final meta-analysis, with 884 cases and 1104 controls participating. The results demonstrated that the polymorphism of IL-1beta(−511C/T) significantly increased the probability of the development of RAS in Europeans. (T vs. C: OR = 1.35, 95%CI = 1.09–1.67; CC vs. CT + TT: OR = 1.77, 95%CI = 1.24–2.53; CC vs. TT: OR = 1.86, 95%CI = 1.18–2.95). Furthermore, the C allele in IL-1beta(+3954C/T) was determined to be related to the risk of RAS in Americans (C vs. T: OR = 1.52, 95%CI = 1.07–2.17) and the presence of the C gene was considered a risk variant (CC + CT vs. TT: OR = 1.46, 95%CI = 1.01–2.11), but no relationship was found between the polymorphism of IL-10(−1082G/A) and the risk of RAS.ConclusionsThe meta-analysis suggested that the mutation of IL-1beta(−511C/T) in Europe and IL-1beta(+3954C/T) in America tend to increase the risk of RAS, but the polymorphism of IL-10(−1082G/A) appears to have no association with RAS risk in America. Further study is required to confirm the above conclusions.     

Association Between Arterial Hypertension and Periodontal Status in Morbidly Obese Patients Who Are Candidates for Bariatric Surgery

ObjectiveThis study aimed to compare the systemic and periodontal conditions between morbidly obese patients with and without hypertension who were candidates for bariatric surgery.MethodsThe study cohort had 111 morbidly obese patients stratified into two groups: patients with (G1 = 54) and without (G2 = 57) arterial hypertension. The following characteristics were compared between the two groups: (i) education level; (ii) anthropometric parameters [weight, height, body mass index (BMI), waist and hip circumferences and waist-to-hip ratio (WHR)]; (iii) risk of developing cardiovascular diseases (based on patients’ sex, age and WHR); (iv) behaviours regarding oral hygiene; and (v) periodontal status. The t-test, Mann–Whitney U-test, chi-square test and logistic regression were applied, with a significance level of 5%.ResultsPatients in G1 had a lower level of education (P = 0.002). There were no intergroup differences for weight (P = 0.211), height (P = 0.126), BMI (P = 0.551), waist circumference (P = 0.859) and WHR (P = 0.067); however, patients in G2 had a smaller hip circumference (P = 0.029), and 78% of patients in G1 had a high/very high risk of developing cardiovascular diseases. The prevalence of periodontitis was 72.2% (n = 39) in G1 and 38.6% (n = 22) in G2. On logistic regression analysis, age [adjusted odds ratio (OR) = 1.07; 95% CI = 1.01–1.13; P = 0.008) and the presence of arterial hypertension (OR = 2.77; 95% CI = 1.17–6.56; P = 0.019) were identified as the independent variables associated with periodontitis.ConclusionMorbid obesity and arterial hypertension are associated with a higher prevalence of cardiovascular diseases. Moreover, morbidly obese patients with hypertension have a higher prevalence of periodontitis and greater severity of periodontal disease than those without hypertension.     

EFFECT OF LOCALLY DELIVERED BISPHOSPHONATES ON ALVEOLAR BONE: A SYSTEMATIC REVIEW AND META-ANALYSIS

ObjectiveTo assess the effect of locally applied bisphosphonate drugs on alveolar bone defects caused by periodontitis and marginal bone level after placement of dental implants.Materials and MethodsThree electronic databases (PubMed/MEDLINE, Web of Science, and Scopus) were searched from January 2010 until May 2020 for randomized controlled clinical trials reporting the effect of locally delivered bisphosphonates on alveolar bone. The risk of bias was assessed and quantitative synthesis was conducted with both fixed and random-effects meta-analyses by using RevMan version 5.3. Subgroup and sensitivity analyses were performed whenever required.ResultsAmong the included studies, the effect of locally delivered bisphosphonates on alveolar bone regeneration in periodontitis was measured by 15 studies and on marginal bone level after installation of dental implants by three studies. Bisphosphonates showed significantly higher intrabony defect depth reduction than placebo/control in vertical bone defects treated with non-surgical approach (MD = 1.69mm; 95% CI, 1.32-2.05; P < 0.00001; I²=93%) or surgical approach (MD = 0.70mm; 95% CI, 0.23-1.16; P = 0.003; I² = 78%) and in class II furcation defects treated with non-surgical approach (MD = 1.61mm; 95% CI, 1.15-2.07; P < 0.00001; I² = 99%) or surgical approach (MD = 0.24mm; 95% CI, 0.05-0.42; P = 0.01; I² = 62%). Clinical attachment loss increased by 1.39mm (95% CI, 0.92-1.85; P < 0.01; I²=93%) and 1mm (95% CI, 0.75-1.26; P < 0.001; I² = 0%) in vertical bone defects after non-surgical and surgical treatments, respectively, and by 1.95mm (95% CI, 1.37-2.53; P < 0.00001; I² = 96%) and 0.84mm (95% CI, 0.58-1.10; P < 0.01, I² = 47%) after non-surgical and surgical treatment in class II furcation defects, respectively. Lesser marginal bone loss during pre-loading (MD = -0.18 mm; 95% CI, -0.24- -0.12; P<0.00001; I²=0%) and 1-year post-loading (MD = -0.33 mm; 95% CI, -0.59–0.07; P = 0.01; I² = 0%) periods was observed when bisphosphonate coated dental implants were used.ConclusionLocally delivered bisphosphonates induce bone regeneration in periodontal defects and decrease the rate of marginal bone loss after dental implant therapy.     

Association of -1082 interleukin-10 gene polymorphism in Peruvian adults with chronic periodontitis

Objectives: The aim of this study was to assess association of the -1082 IL-10 gene polymorphism with chronic periodontitis CP in a Peruvian population. Study Design: Samples of venous blood and DNA were obtained from 106 Peruvian subjects: a) 53 periodontally healthy; and b) 53 with CP. The association of the -1082 IL-10 promoter sequences was assessed by Polymerase chain reaction-restriction fragment length polymorfism (PCR-RFLP). Student’s t test were used to assess the clinical parameters, as well as the χ2 test and the odds ratio (OR), with 95% confidence intervals (CI) used performed for estimates regarding genotype and allele frequencies. Results: There were statistically significant differences between groups regarding the mean bleeding on probing, mean attachment level and mean probing depth (p < 0.00001) indicating that the matching based on the evaluated groups was adequate. The χ2 test found a statistically significant imbalance of genotypes between groups (p = 0.0172). The prevalence of CP was significantly higher in subjects harboring at least one A allele at position -1082 (AA and GA genotypes) in comparison to patients with the GG genotype (OR = 2.96; CI: 0.52; 5.41; p = 0.0099). Equally, subjects with the AA genotype were significantly associated to a diagnosis of CP (OR = 2.71; CI: 0.38; 5.04; p = 0.0231). On the other hand, subjects presenting a healthy periodontal status presented at least one G allele in comparison with the AA genotype (OR = 0.37; CI: 0.05, 0.69; p = 0.0231). For subjects with the GG genotype, the same positive association was observed (OR = 0.34; CI: 0.06, 0.62; p = 0.0099). There were no significant differences between groups amongst subjects with the GA genotype (OR = 1.19; CI: 0.22, 2.16; p = 0.6774). Conclusions: Within the limits of this study, IL-10 gene polymorphism at position -1082 does not appear to be associated to CP. Conversely, subjects with AA genotype seem to be at an increased risk of developing CP. Key words:According to MeSH documentation, chronic periodontitis, cytokines, genetic polymorphism, interleukin-10, periodontal disease.     

Orthodontically induced external apical root resorption in patients treated with fixed appliances vs removable aligners

Objective:To determine whether orthodontic treatment with removable aligners vs fixed orthodontic appliances is associated with a different frequency of orthodontically induced external apical root resorption (OIEARR) when genetic, radiographic, and clinical factors are accounted for.Materials and Methods:Three hundred seventy-two orthodontic patients treated with removable aligners (Invisalign) or fixed appliances were genetically screened for interleukin 1B gene (IL1B) (rs1143634), interleukin 1 receptor antagonist gene (IL1RN) (rs419598), and osteopontin gene (SPP1) (rs9138/rs11730582). Twelve clinical variables, potentially associated with OIEARR, were also considered. Subjects were divided according to the presence of radiographically determined OIEARR (>2 mm). The association between OIEARR and appliance type, and radiographic, clinical and genetic factors, was assessed using backward stepwise conditional logistic regression. Odds ratios (ORs) and 95% confidence intervals (CIs) were reported.Results:Reliability of the methods was adequate. Clinical case complexity (American Board of Orthodontics [ABO] Discrepancy Index) (OR: 1.032; 95% CI: 1.005–1.061; P = .021) and extent of incisor apical displacement in the sagittal plane (OR: 1.478; 95% CI: 1.285–1.699; P = .001) were associated with an increased OIEARR risk. After adjusting for associations between clinical/radiographic/genetic factors, there were no statistically significant differences with respect to OIEARR or type of orthodontic appliance used, whether removable aligners or fixed appliances (OR: 1.662; 95% CI: 0.945–2.924; P = .078). Only subjects homozygous for the T allele of IL1RN (rs419598) were more prone to OIEARR during orthodontic treatment (OR: 3.121; CI: 1.93–5.03; P < .001).Conclusions:A similar OIEARR predisposition was identified using either removable aligners (Invisalign) or fixed appliances.     

Investigation of interleukin‐13 gene polymorphisms in individuals with chronic and generalized aggressive periodontitis in a Taiwanese (Chinese) population

Wu Y‐M, Chuang H‐L, Ho Y‐P, Ho K‐Y, Tsai C‐C. Investigation of interleukin‐13 gene polymorphisms in individuals with chronic and generalized aggressive periodontitis in a Taiwanese (Chinese) population. J Periodont Res 2010; 45: 695–701. © 2010 John Wiley & Sons A/S Background and Objective: The interleukin‐13 (IL‐13) ?1112 C/T polymorphisms have been analyzed previously in a North European population of patients with aggressive periodontitis. The present study was carried out to investigate the association of polymorphisms in the IL‐13 gene with susceptibility to periodontitis in a Taiwanese population. Material and Methods: The genotyping of IL‐13 ?1112 C/T polymorphisms in 60 patients with aggressive periodontitis, 204 patients with chronic periodontitis and 95 healthy controls was carried out using the polymerase chain reaction–restriction fragment length polymorphism technique. Genotypes and allele frequencies among study groups were compared using Fisher’s exact test (p < 0.05). Pearson’s chi‐square test was used for analysis of the Hardy–Weinberg equilibrium. Results: The distributions of CC genotypes and C alleles between patients with aggressive periodontitis and healthy controls were significantly different (p = 0.034 and 0.046). After adjustment for age, gender, betel nut chewing and smoking status using logistic regression analysis, the odds ratio (OR) was 6.45 [95% confidence interval (CI) = 1.99–23.72, p = 0.003] for aggressive periodontitis. However, the CC genotype was only significantly associated with the risk of aggressive periodontitis in the nonsmoking group (OR = 4.48, 95% CI = 1.31–16.93, p = 0.020). Conclusion: The CC genotype or C allele appears to increase the risk of developing aggressive periodontitis in Taiwanese subjects.     

Evaluation of the FDI Chairside Guide for Assessment of Periodontal Conditions: A Multicentre Observational Study

ObjectiveThere is a need to develop easy-to-use tools to screen for periodontal conditions in daily practice. This study aimed to evaluate the FDI World Dental Federation “Chairside Guide” (FDI-CG) developed by the Task Team of the FDI Global Periodontal Health Project (GPHP) as a potential tool for screening.MethodsDatabases from 3 centres in Germany, Hong Kong, and Spain (n = 519) were used to evaluate the association of the FDI-CG and its individual items with the periodontitis case definitions proposed by the Centers for Disease Control and Prevention (CDC) and the American Academy of Periodontology (AAP) for population-based surveillance of periodontitis.ResultsStatistically significant differences were observed among the databases for the prevalence of periodontitis and the items included in the FDI-CG. The FDI-CG score and its individual components were significantly associated with the periodontal status in the individual databases and the total sample, with bleeding on probing showing the strongest association with severe periodontitis (odds ratio [OR] = 12.9, 95% CI [5.9; 28.0], P < .001, for those presenting bleeding on probing >50%), followed by age (OR = 4.8, 95% CI [1.7; 4.2], P = .004, for those older than 65 years of age). Those subjects with a FDI-CG score >10 had an OR of 54.0 (95% CI [23.5; 124.2], P < .001) and presented with severe periodontitis. A significant correlation was found between the different FDI-CG scoring categories (mild, moderate, and severe) and the categories for mild, moderate, and severe periodontitis using the Centers for Disease Control and Prevention and the American Academy of Periodontology criteria (r = 0.57, Spearman rank correlation test, P < .001).ConclusionThe FDI Chairside Guide may represent a suitable tool for screening the periodontal condition by general practitioners in daily dental practice.     

Coronary heart disease and chronic periodontitis: is polymorphism of interleukin‐6 gene the common risk factor in a Chinese population?

Oral Diseases (2011) 17 , 270–276 Objectives: Coronary heart disease (CHD) and chronic periodontitis (CP) both are multifactorial chronic diseases and related to inflammation. Interleukin‐6 (IL‐6) plays an important role in the pathogenesis of inflammatory diseases. The purpose of the study was to investigate the association among IL‐6 gene polymorphisms, CP and CHD susceptibility in a Chinese population. Material and methods: The investigation was conducted as a case‐control study involving 505 individuals: 113 patients with CHD and CP, 84 patients with CHD, 178 patients with CP and 130 control individuals. The polymorphisms of IL‐6 gene were analyzed by polymerase chain reaction‐restriction fragment length polymorphism. Relationships between the distributions of the genotypes and risk factors were also assessed. Results: Mutations at the loci ‐174 G/C, ‐597 G/A of IL‐6 were rare in a Chinese population. No significant difference for IL‐6‐572C/G polymorphism was detected among moderate CP group, severe CP group and control (P = 0.312 and 0.481), significant differences were found between CHD groups and non‐CHD groups (P ≤ 0.001). After adjustment for CHD risk factors, the G allele resulted in an increased risk (OR = 1.676‐1.856), the GG/CG genotype was nearly two times higher risk compared to CC genotype (OR = 2.010‐2.136). Conclusions: IL‐6‐572C/G polymorphism did not correlate with CP susceptibility, but might be a potential risk factor for CHD in a Chinese population.     

Influence of cytotoxic T lymphocyte antigen-4 (CTLA-4) gene polymorphisms in periodontitis

AimPersistent host inflammatory immune response against the pathogens results in the destruction of periodontal tissues. Cytotoxic T lymphocyte antigen 4 (CTLA-4) is a particularly important molecule in down-regulating T-cell expansion and cytokine production. This study aimed to assess three functional SNPs within CTLA-4 gene, ?1722 T/C, ?318 C/T, and +49 A/G in patients with aggressive or chronic periodontitis.Materials and methodsA total of 197 patients with periodontitis (71 aggressive and 126 chronic periodontitis) and 218 healthy controls were recruited. All samples were genotyped for CTLA-4 gene polymorphisms by polymerase chain reaction-amplification refractory mutation system (PCR-ARMS).ResultsThe allelic and genotype frequencies of only +49 A/G SNP were more prominence in patients with chronic periodontitis (CP) than that controls (0.0005 and 0.001, respectively). Multivariate logistic regression analysis was demonstrated that homozygosity in +49 G/G had profoundly increased susceptibility for CP, OR = 3.7 (95% CI; 1.6–8.5, P = 0.001). In addition, comparison of CTLA-4 SNPs between patients with CP and aggressive periodontitis (AgP) revealed that heterozygosity in ?1722 T/C polymorphism of CTLA-4 gene had a significantly higher risk for CP compared with AgP with a calculated odds ratio of 2.18 (95% CI; 1.17–4.06, P = 0.01).ConclusionThese results suggest that CTLA-4 gene variants might be associated to susceptibility to specific form of periodontitis and participate in the CP development.     

Analysis of the interleukin-6 gene promoter polymorphisms in Czech patients with chronic periodontitis

BACKGROUND: Chronic periodontitis is an inflammatory disease, which is a major cause of tooth loss. The proinflammatory cytokines interleukin-1 (IL-1) and interleukin-6 (IL-6) are key regulators of the host response to microbial infection and major modulators of extracellular matrix catabolism and bone resorption. The purpose of this study was to investigate the associations of chronic periodontitis with IL-6 gene polymorphisms (at positions -597 [G/A], -572 [G/C], and -174 [G/C]). METHODS: We analyzed allele, genotype, and haplotype distributions of the IL-6 promoter variants in a case-control study involving 148 patients with chronic periodontitis and 107 unrelated controls. RESULTS: Our results showed significant differences in the distributions of alleles and genotypes of the IL-6 (-572 G/C) polymorphism between patients and the control population (chi2 = 10.393, P= 0.001, P(corr) < 0.01). The difference was due to the underrepresentation of the -572 G/C heterozygotes in patients (6.1%) compared to controls (19.6%). Although no variant "CC" homozygotes were detected in our cases and controls, heterozygosity protected against chronic periodontitis, representing a 73% reduction of risk (odds ratio [OR] = 0.27, 95% confidence interval: 0.12-0.61) compared to wild-type homozygotes. However, there were no significant differences in genotype or allele frequencies between both groups for IL-6 -597 G/A and -174 G/C polymorphisms. CONCLUSION: This study is the first, to our knowledge, suggesting that the -572 G/C polymorphism of the IL-6 gene may be one of the protective factors associated with lower susceptibility to chronic periodontitis.     

Porphyromonas gingivalis HmuY‐Induced Production of Interleukin‐6 and IL‐6 Polymorphism in Chronic Periodontitis

Background: In chronic periodontitis (CP), the gene polymorphism of interleukin‐6 (IL‐6) to 174C/G has been associated with the altered production of this cytokine. The aim of this pilot study is to compare the allelic and genotypic frequencies in patients with CP with control individuals without periodontitis (NP) and to measure the production of IL‐6 by whole blood cells stimulated with Porphyromonas gingivalis HmuY protein. Methods: DNA was isolated from peripheral blood cells of 49 patients with CP and 60 control individuals classified as NP, and genotyping was performed by polymerase chain reaction using sequence‐specific primers. Whole blood cells from 29 patients with CP and 30 control individuals were stimulated for 48 hours with HmuY, and IL‐6 levels were measured using enzyme‐linked immunosorbent assay. Results: The proportion of individuals carrying the G allele at position –174 of the IL‐6 gene was higher in the group with CP (85.7%) than in the normal control group (73.3%; P <0.03). P. gingivalis HmuY‐induced production of IL‐6 was higher in the group with CP (P <0.05). Conclusions: Our findings suggest that P. gingivalis HmuY may be associated with increased IL‐6 production during CP. Furthermore, patients with periodontitis and individuals with higher HmuY‐induced production of IL‐6 show a high frequency of the G allele at position –174.     

Association between genetic polymorphisms in DEFB1 and microRNA202 with caries in two groups of Brazilian children

ObjectiveThis replication study aimed to evaluate an association between caries experience and polymorphisms in DEFB1 and miRNA202 in two different Brazilian groups.DesignThe population consisted in 312 Brazilian children. Genomic DNA for was extracted from buccal cells isolated from saliva. The genotyping analysis of the polymorphisms in DEFB1 and miRNA202 was performed by real-time polymerase chain reactions. The associations between caries experience, genotype and allele distribution was performed, with an alpha of 0.05.ResultsA statistical significant difference was observed between allele distribution and the polymorphism rs12355840 in the miRNA202 for permanent dentition in the Manaus group, in which individuals that carry the allele C had almost three times more chance to have caries (p = .021; OR = 2.7, 95% CI = 1.1–6.7). In the Ribeirão Preto group there was a statistical significant difference for the polymorphism rs11362 in the DEFB1 for both dentition in alleles (p = .043) and genotype (p = .020) distributions. The T allele increased in two times the chance to have caries (OR = 2.03; 95% CI = 1.05–4.07).ConclusionIn conclusion, the allelic distribution of the polymorphism rs12355840 in miRNA202 was associated with caries experience in the Manaus group. In the Ribeirão Preto group, the allelic and genotypic distributions in the polymorphism rs11362 in DEFB1 were associated with caries experience.     

Endodontics Specialists’ Practice during the Initial Outbreak of Coronavirus Disease 2019

IntroductionThe first outbreak of coronavirus disease 2019 (COVID-19) in the United States resulted in a nationwide closure of dental offices that created an oral health crisis. The aim of this observational study was to analyze and compare the characteristics of patients who visited 2 private endodontics offices from March 16 to May 31, 2020, compared with the same period in 2019.MethodsDemographic, diagnostic, and procedural data of 1520 (693 in 2020 and 827 in 2019) patient visits were collected. Bivariate and multiple logistic regression analyses were used to assess the impact of the COVID-19 outbreak on patient-related variables.ResultsBivariate analyses showed that the number of patient visits decreased in April and May 2020 (P < .0001). In 2020, patients’ self-reported pain level was higher, they were more frequently diagnosed with pulp necrosis and acute apical abscess, and they received more incisions for drainage (P < .05). Multiple logistic regression analyses showed that the COVID-19 outbreak was associated with less visits for older patients (>49.5 years) (odds ratio [OR] = 0.720; 95% confidence interval [CI], 0.573–0.906), more patients with kidney diseases (OR = 2.690; 95% CI, 1.143–6.331), higher levels of pain on percussion (OR = 2.277; 95% CI, 1.718–3.016), less cases with previously initiated treatment (OR = 0.242; 95% CI, 0.080–0.731), less periapical diagnoses of asymptomatic apical periodontitis (OR = 0.510; 95% CI, 0.306–0.849), and a higher number of nonsurgical root canal treatments (OR = 2.073; 95% CI, 1.397–3.074) and apicoectomies (OR = 2.799; 95% CI, 1.367-5.729).ConclusionsThese findings show that the public health burden of endodontic infections was more intense during the initial outbreak of COVID-19.     

Cyclooxygenase-2 Gene-765 single nucleotide polymorphism as a protective factor against periodontitis in Taiwanese

Aim: Prostaglandin E₂ (PGE₂) is considered to be an important mediator of tissue destruction in periodontitis. The cyclooxygenase (COX) catalyses the production of PGs. COX‐2, which is induced in an inflammatory response, is responsible for PGs synthesis at sites of inflammation. A single nucleotide polymorphism of COX‐2^?765 has been shown to alter the expression of the COX‐2 gene. The purpose of the present study was to evaluate the association of the COX‐2^?765 polymorphism and susceptibility to periodontitis in Taiwanese. Material and Methods: Eighty‐five cases of aggressive periodontitis (AgP), 343 cases of chronic periodontitis (CP) and 153 cases of healthy controls (HC) were recruited for the study. Genotypes of COX‐2^?765 were determined by polymerase chain reaction‐restriction fragment length polymorphism (PCR‐RFLP). The distribution of genotypes among groups was compared by logistic regression analyses. The risk for periodontitis associated with genotypes was calculated as the odds ratio (OR). Results: The prevalence of the GC and CC genotypes was significantly lower in AgP (5%) and in CP (29%) compared with the HC (42%). The ORs for carriage of the ?765C allele (GC+CC versus GG) in AgP and CP were 0.068 (95% CI=0.020–0.173, p<0.0001) and 0.571 (95% CI=0.385–0.849, p=0.006), respectively. After adjustment for age, gender and smoking status, the OR was 0.071 (95% CI=0.017–0.219) and 0.552 (95% CI=0.367–0.829) for AgP and CP, respectively. Conclusions: The results of the study suggest that the ?765G to C polymorphism of the COX‐2 gene is associated with a decreased risk for periodontitis in Taiwanese, especially in AgP. However, the biological meaning needs further investigation.     

Meta‐Analysis of Association Between Interleukin‐1β C‐511T Polymorphism and Chronic Periodontitis Susceptibility

Background: Many studies have been conducted to explore the association between interleukin (IL)‐1β C‐511T polymorphism and risk of chronic periodontitis (CP) but with different or even contradictory results. A meta‐analysis was performed to further explore their association. Methods: PubMed, Chinese National Knowledge Infrastructure, and EMBASE were searched up to September 30, 2014 for relevant case‐control studies. Two authors (D‐YL and L‐YX) independently selected studies and extracted data from included studies. The meta‐analysis was performed using comprehensive meta‐analysis software. Results: Nineteen case‐control studies involving 2,173 patients with CP and 3,900 healthy controls were included. Using a random‐effects meta‐analysis model, a non‐significant association between IL‐1β C‐511T polymorphism and CP was identified (T versus C: odds ratio [OR] = 1.03, 95% confidence interval [CI] = 0.85 to 1.25; TT versus CC: OR = 1.03, 95% CI = 0.72 to 1.46; CT versus CC: OR = 0.96, 95% CI = 0.71 to 1.30; CT + TT versus CC: OR = 1.00, 95% CI = 0.74 to 1.34; TT versus CT + CC: OR = 1.05, 95% CI = 0.81 to 1.38), and sensitivity analysis indicated that the results were robust. Subgroup analyses also revealed a non‐significant association. No publication bias was detected. Conclusions: Based on currently available evidence, IL‐1β C‐511T polymorphism is not associated with the risk of developing CP. Additional research is warranted to further explore and confirm the association of genetic polymorphism and CP.