Identification of genetic risk factors for periodontitis and possible mechanisms of action

Genetic Association of ICAM-1 (rs5498) Gene Polymorphism With Susceptibility to Stage II Grade B Periodontitis: A Case-Control Study in South Indian Population

INTRODUCTION

In the contemporary perspective, periodontitis is considered a complex issue triggered and perpetuated by bacteria but strongly influenced by the way the body reacts to bacterial plaque. Recent research has indicated that variations in genes might have an impact on the development of periodontitis. This study was conducted to explore a probable link between the genetic variations in intercellular adhesion molecule-1 (ICAM-1) represented by rs5498 and the occurrence of periodontitis.  Methods: A total of 100 participants, 50 with periodontitis and 50 with periodontally healthy or mild gingivitis, were recruited for this study. Whole blood drawn from the participants was used to obtain genomic DNA. The ICAM-1 gene polymorphism (rs5498) was determined using polymerase chain reaction (PCR) amplification and digestion. The ICAM-1 gene's flanking primers were used to amp up the DNA. For statistical analysis, the genotype that was analyzed using the pattern of restriction fragment length polymorphism was recorded. The Chi-square test compared genotype and allele frequency distributions between both groups. The odds ratio with 95% confidence intervals with each individual allele or genotype was used to compute the risk. Statistical significance was established in all tests when the p-value was less than 0.05.

RESULTS

 There was no discernible difference between the genotype frequencies of patients and controls χ2df (P = 0.6065). The findings demonstrated that no significant difference was present between the two groups for homozygous or heterozygous mutant genotypes (AA vs. AG+GG; P = 0.6854). There was no discernible difference in the detected frequencies of the A allele (58% vs. 61%), G allele (42% vs. 39%), TT (16% vs. 24%), AG (40% vs. 36%), and TT genotypes in the studied groups.

CONCLUSION

According to the results of the current investigation, the ICAM-1 (rs5498) gene polymorphism is not associated with periodontitis in the population investigated.

MicroRNAs: The Missing Link between Hypertension and Periodontitis?

Cardiovascular diseases are the leading cause of death worldwide, and arterial hypertension is a recognized cardiovascular risk factor that is responsible for high morbidity and mortality. Arterial hypertension is the result of an inflammatory process that results in the remodeling and thickening of the vascular walls, which is associated with an immunological response. Previous studies have attempted to demonstrate the relationship between oral disease, inflammation, and the development of systemic diseases. Currently, the existence of an association between periodontitis and hypertension is a controversial issue because the underlying pathophysiological processes and inflammatory mechanisms common to both diseases are unknown. This is due to the fact that periodontitis is a chronic inflammatory disease that affects the interface of teeth and surrounding tissues. However, the most likely explanation for understanding this association is related to low-grade chronic inflammation. An initial path in the study of the relationship between the mentioned pathologies is the possibility of an epigenetic influence, mediated by noncoding RNAs as microRNAs. Thus, in the present review we describe the role of microRNAs related to arterial hypertension and/or periodontitis. In addition, we identified 13 common microRNAs between periodontitis and hypertension. According to the predictions of the DIANA-mirPath program, they can regulate genes involved in 52 signaling pathways.

Single nucleotide polymorphisms in inducible nitric oxide synthase gene are not associated with persistent apical periodontitis

The aim of this study was to investigate whether there is an association between inducible in single nucleotide polymorphisms in nitric oxide synthase (rs2297518 and rs2779249) and persistent apical periodontitis. A total of 291 Brazilian subjects were included: 125 with signs/symptoms of persistent apical periodontitis and 166 with root canal-treated teeth exhibiting healthy perirradicular tissues. Endodontically treated patients were followed up after 1 year. The two single nucleotide polymorphisms in nitric oxide synthase were analysed using real-time polymerase chain reaction. Chi-square test and odds ratio with 95% confidence intervals were performed to compare genotype distributions between 'healed' and 'persistent apical periodontitis' groups (p < 0.05). Logistic regression analysis was used to evaluate SNP-SNP interactions. The allele and genotype distributions for the polymorphisms between the persistent apical periodontitis and healed groups were not statistically significant (p > 0.05). In the logistic regression analysis, the polymorphisms were not associated with persistent apical periodontitis and SNP-SNP interactions.

Bioinformatic analysis reveals lysosome-related biomarkers and molecular subtypes in preeclampsia: novel insights into the pathogenesis of preeclampsia

Background: The process of lysosomal biogenesis and exocytosis in preeclamptic placentae plays a role in causing maternal endothelial dysfunction. However, the specific lysosome-associated markers relevant to preeclampsia (PE) are not well-defined. Our objective is to discover new biomarkers and molecular subtypes associated with lysosomes that could improve the diagnosis and treatment of PE. Methods: We obtained four microarray datasets related to PE from the Gene Expression Omnibus (GEO) database. The limma package was utilized to identify genes that were differentially expressed between individuals with the disease and healthy controls. The logistic regression analysis was used to identify core diagnostic biomarkers, which were subsequently validated by independent datasets and clinical samples. Additionally, a consensus clustering method was utilized to distinguish between different subtypes of PE. Following this, functional enrichment analysis, GSEA, GSVA, and immune cell infiltration were conducted to compare the two subtypes and identify any differences in their functional characteristics and immune cell composition. Results: We identified 16 PE-specific lysosome-related genes. Through regression analysis, two genes, GNPTG and CTSC, were identified and subsequently validated in the external validation cohort GSE60438 and through qRT-PCR experiment. A nomogram model for the diagnosis of PE was developed and evaluated using these two genes. The model had a remarkably high predictive power (AUC values of the training set, validation set, and clinical samples were 0.897, 0.788, and 0.979, respectively). Additionally, two different molecular subtypes (C1 and C2) were identified, and we found notable variations in the levels of immune cells present in the two subtypes. Conclusion: Our results not only offered a classification system but also identified novel diagnostic biomarkers for PE patients. Our findings offered an additional understanding of how to categorize PE patients and also highlighted potential avenues for creating treatments for individuals with PE.

Pathogenic associations between oral and gastrointestinal diseases

Both periodontitis and inflammatory bowel disease (IBD) are complex chronic conditions characterized by aberrant host immune response and dysregulated microbiota. Emerging data show an association between periodontitis and IBD, including direct and indirect mechanistic links between oral and intestinal inflammation. Direct pathways include translocation of proinflammatory microbes from the oral cavity to the gut and immune priming. Indirect pathways involve systemic immune activation with possible nonspecific effects on the gut. There are limited data on the effects of periodontal disease treatment on IBD course and vice versa, but early reports suggest that treatment of periodontitis decreases systemic immune activation and that treatment of IBD is associated with periodontitis healing, underscoring the importance of recognizing and treating both conditions.

Dental caries and periodontitis and the risk of myopia in young adults: CHIEF oral health study

Aim

Oral health and ocular diseases may be associated with collagen defects and inflammation status. However, the results from prior studies are conflicting. The aim of this study was to explore the association of dental caries and periodontitis with myopia in young adults.

Materials and methods

A total of 938 military personnel aged 19–39 years receiving both oral and eye examinations from 2018 through 2020 were included in this study in Taiwan. The severity of myopia was graded as no myopia (diopters > − 0.5, N = 459), low myopia (diopters: − 0.5 to -5.9, N = 225) and high myopia (diopters ≤ − 6.0, N = 254). A multiple logistic regression analysis with adjustments for age, body mass index, systolic blood pressure, smoking, alcohol consumption, missing teeth numbers, blood leucocyte counts, triglycerides, high-density lipoprotein, and uric acid were used to determine the associations of actively dental caries, filled teeth and stage II/III periodontitis with myopia.

Results

The presence of any actively dental caries was significantly associated with a higher risk of any myopia (low or high) (odds ratio [OR] and 95% confidence intervals [95% CI] 1.42 [1.04–1.94]), whereas there was no association for filled teeth. Moreover, the association for stage II/III periodontitis was only observed with high myopia (OR: 1.52 [1.07–2.15]) and was not observed with low myopia.

Conclusions

Our findings suggest that only actively dental caries and a higher severity of periodontitis were associated with myopia among young adults, thus highlighting the dental inflammation status in the oral cavity as a potential link to ocular diseases.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12903-022-02413-w.

Profile of vitamin D receptor gene polymorphism TaqI in patients with periodontitis

The present study aimed to assess the incidence of the vitamin D receptor (VDR) gene polymorphism TaqI in patients with periodontitis, and the potential association of this polymorphism with the severity of the disease. This was a case-controlled study, which included 162 adults divided into two groups as follows: Case group (81 patients diagnosed with periodontitis) and control group (81 patients without periodontitis). Venous blood was obtained from each sample from which DNA was extracted. The gene polymorphism was determined using restricted fragment length polymorphism-PCR and DNA sequencing to identify endonuclease restrictions in exon 9 (TaqI). The data were analyzed using an independent samples t-test. VDR gene polymorphisms were detected in periodontitis cases with TT (86.4%), Tt (12.4%) and tt (1.2%) genotypes. DNA sequencing confirmed a change in the sequence of the VDR gene nucleotides in patients with periodontitis. The data indicated that the severity of periodontal tissue damage may be influenced by changes in the nucleotide sequence.

Gene Interaction Network Analysis Reveals IFI44L as a Drug Target in Rheumatoid Arthritis and Periodontitis

Simple Summary

In spite of substantial investigation, the biological link between periodontitis and rheumatoid arthritis remains unexplained. This study intended to correlate periodontitis and rheumatoid arthritis gene expression patterns to find shared targets for both the disease. We identified the differentially expressed genes (DEGs) in periodontitis and rheumatoid arthritis. The network was built by integrating DEGs and ranking the genes using GeneMANIA. FINDSITEcomb2.0 was used to find a possible inhibitor for the top-ranked gene. Further, the binding effectiveness and protein-ligand complex stability were then determined by molecular docking and molecular dynamics. The network analysis showed IFI44L as a highly ranking gene implicated in most immunological pathways. A virtual screening of 6507 compounds revealed vemurafenib as the best candidate for the IFI44L target. Molecular docking and molecular dynamics modelling revealed the stability of the IFI44L-vemurafenib complex, which suggest IFI44L is potential target and vemurafenib could be the better candidate to treat both diseases.

Abstract

Objective: Despite extensive research on periodontitis and rheumatoid arthritis, the underlying molecular connectivity between these condition remains largely unknown. This research aimed to integrate periodontitis and rheumatoid arthritis gene expression profiles to identify interconnecting genes and focus to develop a common lead molecule against these inflammatory conditions. Materials and Methods: Differentially expressed genes (DEGs) of periodontitis and rheumatoid arthritis were identified from the datasets retrieved from the Gene Expression Omnibus database. The network was constructed by merging DEGs, and the interconnecting genes were identified and ranked using GeneMANIA. For the selected top ranked gene, the potential inhibitor was searched using FINDSITE^comb2.0. Subsequently, the molecular docking and molecular dynamics were performed to determine the binding efficiency and protein-ligand complex stability, respectively. Results: From the network analysis, IFN-induced protein 44-like (IFI44L) was identified as a top ranked gene involved in most of the immunological pathway. With further virtual screening of 6507 molecules, vemurafenib was identified to be the best fit against the IFI44L target. The binding energy and stability of IFI44L with vemurafenib were investigated using molecular docking and molecular dynamics simulation. Docking results show binding energy of −7.7 Kcal/mol, and the simulation results show stability till 100 ns. Conclusions: The identified IFI44L may represent a common drug target for periodontitis and rheumatoid arthritis. Vemurafenib could be a potent anti-inflammatory drug for both diseases.

Bioprospecting Phenols as Inhibitors of Trichothecene-Producing Fusarium: Sustainable Approaches to the Management of Wheat Pathogens

Fusarium spp. are ubiquitous fungi able to cause Fusarium head blight and Fusarium foot and root rot on wheat. Among relevant pathogenic species, Fusarium graminearum and Fusarium culmorum cause significant yield and quality loss and result in contamination of the grain with mycotoxins, mainly type B trichothecenes, which are a major health concern for humans and animals. Phenolic compounds of natural origin are being increasingly explored as fungicides on those pathogens. This review summarizes recent research activities related to the antifungal and anti-mycotoxigenic activity of natural phenolic compounds against Fusarium, including studies into the mechanisms of action of major exogenous phenolic inhibitors, their structure-activity interaction, and the combined effect of these compounds with other natural products or with conventional fungicides in mycotoxin modulation. The role of high-throughput analysis tools to decipher key signaling molecules able to modulate the production of mycotoxins and the development of sustainable formulations enhancing potential inhibitors’ efficacy are also discussed.

Dental Fluorosis and Periodontium: an Original Research Report of In Vitro and In Vivo Institutional Studies

Fluorosis is one of the global problems that have persisted for a very long time now without any specific treatment and cure. Fluoride is known for its influence on the tooth structures like enamel and dentin, but little information exists on its effect on the surrounding periodontal structures and bone. With this background, we conducted multiple studies assessing etiological, diagnostic, therapeutic and clinical criteria in subjects with and without dental fluorosis in a single group of the population residing in high fluoride water areas (1.5-3.0 ppm) of Davangere District, Karnataka, India. These preliminary studies conducted are hereby elaborately presented and discussed in this comprehensive review article along with their important conclusions.

Characterization of the Subgingival Cultivable Microbiota in Patients with Different Stages of Periodontitis in Spain and Colombia. A Cross-Sectional Study

The objective was to characterize and compare the subgingival microbiota in patients diagnosed according to the World Workshop on the Classification of Periodontal and Peri-Implant Diseases and Conditions 2018. For this cross-sectional study, Spanish and Colombian subjects (characterized as health/gingivitis, periodontitis in stages I-II or stages III-IV) were clinically assessed, and subgingival samples were taken and processed by culture. The comparisons among patients with periodontal status (and between countries) was made using Mann–Whitney, Kruskal–Wallis, ANOVA and chi-square tests. The final sample consisted of 167 subjects. Eikenella corrodens and Parvimonas micra were more frequently detected in health/gingivitis and Porphyromonas gingivalis in periodontitis (p < 0.05). Higher total counts were observed in Colombia (p = 0.036). In Spain, significantly higher levels of P. gingivalis and Campylobacter rectus were observed, and of Tannerella forsythia, P. micra, Prevotella intermedia, Fusobacterium nucleatum, Actinomyces odontolyticus and Capnocytophaga spp. in Colombia (p < 0.001). P. micra was more prevalent in health/gingivitis and stage I-II periodontitis in Colombia, and P. gingivalis in all periodontitis groups in Spain (p < 0.05). As conclusions, significant differences were detected in the microbiota between health/gingivitis and periodontitis, with minor differences between stages of periodontitis. Differences were also relevant between countries, with Colombia showing larger counts and variability of bacterial species.

A Proteomic Analysis of Discolored Tooth Surfaces after the Use of 0.12% Chlorhexidine (CHX) Mouthwash and CHX Provided with an Anti-Discoloration System (ADS)

Chlorhexidine (CHX) is considered the gold standard for the chemical control of bacterial plaque and is often used after surgical treatment. However, CHX employment over an extended time is responsible for side effects such as the appearance of pigmentations on the teeth and tongue; the discoloration effects are less pronounced when using a CHX-based mouthwash with added an anti-discoloration system (ADS). The aim of this study was to evaluate, using one- and two-dimensional gel electrophoresis combined with mass spectrometry, the possible proteomic changes induced by CHX and CHX+ADS in the supragingival dental sites susceptible to a discoloration effect. The tooth surface collected material (TSCM) was obtained by curettage after resective bone surgery from three groups of patients following a supportive therapy protocol in which a mechanical control was combined with placebo rinses or CHX or a CHX+ADS mouthwash. The proteomic analysis was performed before surgery (basal conditions) and four weeks after surgery when CHX was used (or not) as chemical plaque control. Changes in the TSCM proteome were only revealed following CHX treatment: glycolytic enzymes, molecular chaperones and elongation factors were identified as more expressed. These changes were not detected after CHX+ADS treatment. An ADS could directly limit TSCM forming and also the CHX antiseptic effect reduces its ability to alter bacterial cell permeability. However, Maillard’s reaction produces high molecular weight molecules that change the surface properties and could facilitate bacterial adhesion.

Influence of female sex hormones in different stages of women on periodontium

The primary etiologic factor for periodontal diseases is “Dental plaque.” Although pathogenic bacteria in dental plaque are required for the incidence of periodontal disease, a susceptible host is also very important. The susceptibility of the host can be modified by many systemic factors with hormones level being one. The periodontium shows an exaggerated inflammatory response to plaque modified by female sex hormones during puberty, pregnancy, in women taking oral contraceptives, and at the postmenopausal stage. This review provides an in detail analysis of how periodontium is influenced by the fluctuation in sex steroid hormones of females during different phases of their lifetime and to discuss how much the same hormone at different ages and stages shows an exaggerated gingival response to plaque.

Association of TNF-α-308G/A, -238G/A, -863C/A, -1031T/C, -857C/T polymorphisms with periodontitis susceptibility: Evidence from a meta-analysis of 52 studies

The association between tumor necrosis factor-alpha (TNF-α-308G/A, -238G/A, -863C/A, -1031T/C, and -857C/T) polymorphism and either chronic (CP) or aggressive (AgP) periodontitis susceptibility was conflicting. This meta-analysis aimed to quantitatively estimate the association.A total of 52 studies involving 5519 patients and 7260 controls were identified through a search of multiple electronic databases. Odds ratios (ORs) and their 95% confidence intervals using allele, homozygous, heterozygous, dominant, and recessive genetic models were computed to assess the strength of the association.The TNF-α-308G/A polymorphism was significantly associated with decreased risks of CP (GG vs AA: OR = 0.353, P < .001; GG+GA vs AA: OR = 0.480, P < .001) and AgP (G vs A: OR = 0.651, P < .001; GG vs AA: OR = 0.306, P < .001; GG+GA vs AA: OR = 0.384, P < .001) in Asians. There were no associations between TNF-α-238G/A, -863C/A, -1031T/C, -857C/T polymorphism and susceptibility to AgP. No associations were also found between CP susceptibility and TNF-α-238G/A, -857C/T polymorphism.These findings supported that TNF-α-308G/A polymorphism might be the protective factors of CP and AgP in Asians, and TNF-α-238G/A, -863C/A, -1031T/C, -857C/T polymorphism is not linked to AgP susceptibility.

Periodontitis, Low-Grade Inflammation and Systemic Health: A Scoping Review

Background and objectives: Periodontitis is a multifactorial chronic inflammatory infectious disease in which an infection is necessary, but not sufficient, for development of the condition. Individual susceptibility strictly linked to the immune and inflammatory response of the organism must also be present. Low-grade inflammation (LGI) is a systemic status of chronic sub-clinical production of inflammatory factors. This condition represents a risk factor for many chronic diseases including diabetes, cardiovascular disease, cerebrovascular disease, neurodegenerative disease and cancer. This scoping review aims to clarify, summarize and disseminate current knowledge on the possible link between periodontitis, LGI and systemic health. Materials and Methods: PRISMA Extension for Scoping Reviews guidelines were followed. An ad-hoc created keyword string was used to search the electronic databases of PubMed/Medline, Embase, The Cochrane Library and ClinicalTrials.gov. A hand search of specialized journals and their reference lists was also performed. Results: 14 studies that respected eligibility criteria were selected and analyzed. There is emerging evidence of strong links between periodontitis, LGI and systemic health. On the one hand, periodontitis influences the systemic status of LGI and on the other hand, the systemic production of inflammatory factors affects periodontitis with a bidirectional connection. Conclusions: LGI and the subsequent onset of a systemic inflammatory phenotype can be considered the common substrate of many chronic inflammatory diseases including periodontitis, with multiple mutual connections between them. Understanding of the biological principles and mechanisms underlying such a complex interrelationship could lead to significant improvements in the field of personalized diagnostics and therapeutic protocols.

Oestrogen receptor Rsa I gene polymorphism in osteoporosis periodontitis patients with or without dental fluorosis

Background & objectives:

There is a paucity of information on association between dental fluorosis, osteoporosis and periodontitis. The aim of this pilot study was to evaluate oestrogen receptor (ER) Rsa 1 gene polymorphism in osteoporosis periodontitis patients with and without dental fluorosis.

Methods:

Twenty one primary osteoporotic patients suffering from periodontitis with dental fluorosis and 20 primary osteoporotic patients suffering from periodontitis without dental fluorosis participated in this study. Periodontitis was diagnosed based on age, gender T-scores using clinical parameters such as plaque scores, gingival bleeding scores and probing pocket depth, clinical attachment level (CAL) and severity of dental fluorosis. DNA was genotyped at the RsaI RFLP (in exon 5) inside the ER gene to study ER Rsa I gene polymorphism in osteoporosis periodontitis patients with and without dental fluorosis.

Results:

Patients with dental fluorosis had higher degree of osteoporosis than those without fluorosis. CAL was significantly higher (P<0.05) in those with dental fluorosis compared with those without. Rr heterozygote (21.95%) was observed in patients without fluorosis whereas RR mutant homozygote was absent in both the groups. Rr wild homozygote type was seen more in the patients with fluorosis (51.21%). Significant differences were found in distribution of these genotypes between patients with and without dental fluorosis.

Interpretation & conclusions:

This preliminary study showed the presence of ER I gene polymorphism in osteoporosis periodontitis patients without dental fluorosis. Further studies with large sample size are needed to confirm the association shown in this preliminary study.

Significance of Markers of Monocyte Activation (CD163 and sCD14) and Inflammation (IL-6) in Patients Admitted for Alcohol Use Disorder Treatment

BACKGROUND

Monocyte activation and inflammation are prominent features of alcohol-related liver disease; however, they have not been thoroughly assessed in patients with alcohol use disorder (AUD) without overt liver disease. This study aimed to analyze associations among clinical and laboratory variables and markers of monocyte activation (CD163 and sCD14), and inflammation (interleukin [IL]-6) among AUD patients.

METHODS

We analyzed the aforementioned associations in the highest quartile in 289 patients (77.5% male; median age, 50 years) consecutively admitted for alcohol detoxification in 2 tertiary hospitals in the Barcelona metropolitan area, Spain.

RESULTS

Median alcohol intake was 142 g/d; median glucose, albumin, creatinine, and bilirubin levels (mg/dl), 92, 40, 0.78, and 0.69, respectively; median AST, 41 U/l; median hemoglobin, median corpuscular volume, and platelet count, 14.1 g/dl, 94.8 fL, and 189 × 10⁹ /l, respectively; median cholesterol, triglyceride, fibrinogen, and ferritin levels, 187 mg/dl, 109.3 mg/dl, 341 mg/dl, and 177 ng/ml, respectively. In addition, 36.7% patients had an erythrocyte sedimentation rate >20 mm, 32.5% had a C-reactive protein (CRP) level of >5 mg/l, and 10.9% were hepatitis C virus (HCV)-positive. Median CD163, sCD14, and IL-6 levels were 759, 1.68 × 10⁶ , and 4.37 pg/ml, respectively. On logistic regression analyses, glucose, AST, bilirubin, hemoglobin levels, and HCV infection (adjusted odds ratio [aORs]: 1.01, 1.02, 3.04, and 9.73, respectively) were associated with CD163. Glucose, AST, triglyceride, and CRP >5 mg/l (aORs: 1.02, 1.01, 1.00, and 3.49, respectively) were associated with sCD14. Alcohol consumption upon admission, MCV, total cholesterol levels, and CRP >5 mg/l (aORs: 0.99, 1.05, 0.99, and 2.56, respectively) were associated with IL-6.

CONCLUSIONS

Monocyte activation and systemic inflammation are associated with higher glucose, liver enzyme, and lipid levels, HCV infections, and CRP of >5 mg/l, thus potentially identifying patients with AUD at high risk of midterm poor outcomes.

Association of A-197G polymorphism in interleukin-17 gene with chronic periodontitis: Evidence from six case-control studies with a computational biology approach

AIM

The aim of the present study was to evaluate the association of interleukin-17 (IL-17) A-197G gene polymorphism with chronic periodontitis (CP) in a case-control study, a meta-analysis, and an in silico approach.

METHODS

In the case-control study, 122 cases with CP and 126 healthy controls were recruited; IL-17 A-197G genotyping was performed by polymerase chain reaction-restriction fragment length polymorphism. In the meta-analysis, comprehensive literature retrieval was performed on valid databases to identify relevant studies. Bioinformatics tools were employed to investigate the effects of A-197G transition on the promoter region of IL-17.

RESULTS

Our case-control study revealed a significant association between IL-17 A-197G transition and CP. The overall meta-analysis revealed significant associations between the IL-17 A-197G polymorphism and CP risk in homozygote co-dominant and recessive models. The stratified analysis also showed a statistically significant association between the mentioned transition and CP risk in the Caucasian population. The in silico analysis revealed that the A-197G polymorphism could make changes in protein-binding sites of the IL-17 promoter region.

CONCLUSIONS

Our study supports that IL-17 A-197G transition could be a genetic risk factor for CP. However, further studies with a larger sample size among different ethnicities are required to obtain a more accurate conclusion.

Quality of methods and reporting in association studies of chronic periodontitis and IL1A -889 and IL1B +3953/4 SNPs: A systematic review

OBJECTIVE

The aim of this systematic review was to evaluate the quality of reporting and methodology in genetic association studies between IL1A -889 and IL1B +3954 polymorphisms and chronic periodontitis.

BACKGROUND

Evidence provided by periodontal research on genetic risk factors is of uttermost importance in clinical practice as a possible diagnostic and prognostic tool for periodontitis. Inadequate reporting of results as well as high risk of bias due to methodological inconsistency hampers the integration of evidence in terms of clinical applicability.

METHODS

This review includes case-control studies in humans published between 1997 and July 2017. Searching was conducted through MEDLINE, EMBASE, and search handing. Specific scoring systems have been developed to evaluate the quality of methods and reporting. Each article was scored according to its adequacy, and then, the total number and the percentage of items positively qualified for both methods and reporting were calculated. The quality of methods in studies scoring 0-6, 7-12, and 13-16 was, respectively, considered poor, moderate, and good. For reporting, scores of 0-9, 10-18, and 19-26 were deemed of poor, moderate, and good quality, respectively. Pearson's correlation coefficient was calculated to explore the correlation between the year of publication and the quality in terms of methods and reporting.

RESULTS

From the 531 screened studies, 52 met the inclusion criteria and were thus included in the study. The quality of methods and reporting of published genetic association papers on IL1 and chronic periodontitis is moderate. On a scale from 0 to 16, the mean score for methods of the reviewed studies was 8.19 ± 1.93. The items more frequently considered inadequate concerned the handling of confounders in statistical analysis, especially oral hygiene habits, socioeconomic status, subgingival colonization of specific periodontal pathogens, and stress. A significant positive correlation was found between the year of publication and the quality scores in terms of method (r = 0.401, P = 0.003). In terms of reporting, the mean score was 14.83 ± 3.04 on a scale from 0 to 26 and it was considered overall moderate. No statistically significant correlation was found between the year of publication and the quality of reporting (P = 0.266).

CONCLUSIONS

The association between IL1A -889 and IL1B +3954 polymorphisms and chronic periodontitis is questionable due to methodological inconsistency. Evidence arising from meta-analysis is unreliable due to high risk of bias and moderate quality in terms of reporting.

Outflow Facility in Tube Shunt Fenestration

AIM

Determination of the effect of varying fenestration technique, and simulated patch graft on outflow facility for Baerveldt tube.

MATERIALS AND METHODS

Silicone tubing similar to Baerveldt implant (AMO, Santa Ana, CA) with different fenestrations techniques was connected to a digital manometer in a closed system with a fluid-filled syringe on a stand to adjust pressure. The venting slits included: (A) 4 piercings with 7-0 TG140-8 needle; (B) a 2-mm slit with a 15° blade; (C) 4 piercings with a 15° blade; (D) 9-0 Nylon on CS140-6 needle with suture stenting the fenestration.

RESULTS

For pressures of 10, 20, 30, 40 mm Hg in groups A to D, the average outflow facility (mL/min/mm Hg) were group A: 0.11, 0.20, 0.28, 0.40; group B: 0.30, 0.69, 0.98, 0.93; group C: 0.73, 0.80, 0.81, 0.88; group D: 0.58, 0.65, 0.80, 0.87. For external compression with 10 gram weights at pressures of 10, 20, 30, 40 mm Hg, outflow were group A: 0.0, 0.18, 0.20, 0.53; group B: 0.75, 0.70, 0.97, 1.21. Group C: 0.18, 0.03, 0.57, 0.04. Group D: 0.73, 0.90, 1.13, 0.91.

CONCLUSION

Effectivity of venting slits in maintaining adequate IOP in the early postoperative period for non-valved glaucoma implant is variable, multifactorial and largely intraocular pressure (IOP) dependent.

CLINICAL SIGNIFICANCE

This study explores methods of producing fenestration and the effects on outflow at different pressures in an attempt to determine which fenestration technique has more reproducible results that can be made applicable in clinical practice. This is also the first study to evaluate the effect of external pressures similar to scleral patch graft on the tube fenestrations.

HOW TO CITE THIS ARTICLE

Olayanju J, Borras T, Qaqish B, Fleischman D. Outflow Facility in Tube Shunt Fenestration. J Curr Glaucoma Pract 2018;12(3):113-118.

[Correlation between interleukin-10 polymorphisms and susceptibility to chronic periodontitis among Uygur adults in the Moyu area]

OBJECTIVE

This study aims to investigate the association between interleukin (IL)-10-597 (C/A) single-nucleotide polymorphisms and chronic periodontitis of Moyu Uygur population in Xinjiang Uygur Autonomous Region of China.

METHODS

In accordance with the inclusion and exclusion criteria, the buccal swabs of 300 subjects were randomly selected from the epidemiological investigation of Uygur adults in Moyu county on April and May 2013. The study was conducted on a healthy control group, a mild chronic periodontitis group, and a moderate-to-severe chronic periodontitis group, with each comprising 100 samples. The IL-10-597(C/A) site in the promoter sequences was analyzed using the tetra-primer amplification refractory mutation system-polymerase chain reaction method to test the genotype and allele distributions. Statistical analysis was performed using Chi-squared test and ordinal classification Logistic regression analysis.

RESULTS

The genotype and allele frequencies of the IL-10-597(C/A) site in the healthy control group, mild chronic periodontitis group, and moderate-to-severe chronic periodontitis group exhibited no significant difference (P>0.05). The age of all the samples was associated with chronic periodontitis. The risk of chronic periodontitis in the people of 55-65 years old was 25 times in the people under the age of 35 (OR=25.56, P<0.001).

CONCLUSIONS

The IL-10-597 (C/A) single-nucleotide polymorphisms in the gene promoter are not associated with chronic periodontitis in Uygur adult population.

Association Between Apical Periodontitis and TNF-α -308 G>A Gene Polymorphism: A Systematic Review and Meta-Analysis

Abstract Currently, investigations have focused on the identification of Single Nucleotide Polymorphisms (SNP) involved in host response and its ability to generate an immunity deficiency. The aim of this study was to perform a systematic review (SR) and meta-analysis to evaluate the association between TNF-α -308 G>A polymorphism and apical periodontitis (AP) phenotypes. A broad search for studies was conducted. The following databases were used: PubMed, Scopus, Web of Science, and VHL (Medline, SciELO, Ibecs, and Lilacs). The MeSH terms “Periapical Periodontitis,” “Periapical Abscess,” “Polymorphism, Genetic,” and “Polymorphism, Single Nucleotide” were used. MeSH synonyms, related terms, and free terms were included. Clinical investigations of individuals with different AP phenotypes in permanent teeth were selected. After application of the eligibility criteria, selected studies were qualified by assessing their methodological quality. A fixed effect model was used for the meta-analysis. The initial search identified 71 references. After excluding duplicate abstracts, 33 were selected. From these, two were eligible for quality assessment and were classified as being of moderate evidence. The included studies did not demonstrate association between AP and TNF-α -308 G>A SNP. However, the meta-analysis demonstrated an association between the genotype distribution and AP phenotype (OR= 0.49; confidence interval= 0.25, 0.96; p=0.04). The role of TNF-α -308 G>A SNP in AP phenotypes is debatable. Further studies are needed to confirm and understand the underlying mechanisms of the identified association.

Quantitative Parameters of Interdental Gingiva in Chronic Periodontitis Patients with IFN-γ Gene Polymorphism

Chronic periodontitis (CP), an infectious disease resulting in inflammation within the periodontal tissue, is the main cause of adult tooth loss. CP is a multi-factorial disorder and the interaction between multiple genetic and environmental factors results in the manifestation of this disease. Recent researches in periodontitis has focused on cytokine gene polymorphisms that play important role in periodontal inflammation, but few studies investigated histological change that occur during CP in the supporting tissue of teeth. The aims of this study were to investigate the association of IFN-γ +874 A/T polymorphisms and quantitative parameters of interdental gingiva in CP patients. The study samples were interdental gingiva biopsies from 60 individuals including 38 patients and 22 healthy subjects. After determination of IFN-γ +874 A/T gene polymorphism by amplification refractory mutation system-polymerase chain reaction (ARMS-PCR), patients were divided in three subgroups: 10 AA, 18 AT and 10 TT. After slides preparation, quantitative parameters were estimated by Cavalieri's point-counting method. Statistical analyses were performed using Mann-Whitney and Kruskal-Wallis test to compare differences between groups. The volume density (Vv) of epithelium, connective tissue and its components were significantly different between the control and CP groups (P&lt;0.05). Statistically significant differences in the Vv of collagenous and non-collagenous matrix of interdental gingiva between AA, AT and TT groups were found (P&lt;0.05). Result of present study shows that IFN-γ +874 A/T is strongly associated with some quantitative parameters of connective tissue constituents of interdental papilla in CP patients.

Periodontal disease and women's health

BACKGROUND

Periodontal disease (PD) is a multifactorial inflammatory condition in which inappropriate interaction between the host immune response and specific groups of bacterial pathogens leads to destruction of connective and bone tissues supporting the tooth. Dissemination of pathogens, toxins, and immune complexes from and to periodontal lesions is at the basis of the increasingly recognized association between PD and various systemic diseases (SDs). Considering the growing attention of the medical community to "gender medicine", this review focuses on the association between PD and six systemic conditions heavily impacting women's health, with the aim of providing evidence in support of a joint effort between physicians and dentists to improve clinical management of these conditions.

METHODS

We considered systematic reviews, meta-analyses and narrative reviews evaluating all possible associations between periodontitis, systemic diseases and women.

RESULTS

Gender prevalence for PD is discordant, but the literature strongly supports an association between PD and female infertility and adverse pregnancy outcomes. Moreover, PD is bidirectionally linked to several systemic diseases characterized by an established female gender bias, i.e. osteoporosis (OP), cardiovascular diseases (CVD), autoimmunity, Alzheimer's disease (AD) and cancer.

CONCLUSIONS

Overall, the literature data reviewed here provides a strong foundation for further characterization of molecular and microbial drivers of PD and of several female-prevalent systemic diseases, highlighting the possible importance of a good oral condition in preventing or attenuating women's systemic diseases.

Association of cytokines polymorphisms with chronic peridontitis and rheumatoid arthritis in a Mexican population

OBJECTIVE

Historically, it has been shown that rheumatoid arthritis (RA) and periodontitis (PE) share pathophysiological similarities and possibly a genetic background. In order to elucidate the genetic background between both diseases, we evaluated the distributions of five SNPs genotypes and all the possible haplotypes composed in subjects with isolated RA, PE, combined diseases and healthy controls.

MATERIALS AND METHODS

The study population consisted of 280 Mexican subjects. Genomic DNA was isolated from buccal epithelial cells collected by cheek scrapings and analyzed for the determination of the following SNPs: IL-1α + 4845 (rs17561), IL-1α -889 (rs1800587), IL-1β + 3954 (rs1143634), IL-1β -511(rs16944) and TNF-α -308 (rs1800629).

RESULTS

After adjustment for age, sex and smoking status, multiple logistic regression analysis revealed a no significant association in the genotype frequencies of TNF-α -308 and IL-1α + 4845 SNPs. Otherwise a significant association was observed in IL-1β + 3954 and IL-1β -511 (p < 0.05) while IL-1α -889 was of borderline statistical significance (p = 0.054). Also, we found three negative associated haplotypes with PE: IL-1α + 4845 G/IL-1β -511 A, IL-1β + 3954 C/IL-1β -511 A and interestingly IL-1α -889 C/IL-1β -511 A also with a positive association with RA.

CONCLUSIONS

Some genotypes and haplotypes are associated with the diseases. But it seems that the genetic background of the association between RA and PE needs to be explored deeper.

Functional Haplotypes in Interleukin 4 Gene Associated with Periodontitis

Chronic periodontitis (CP) is an infectious inflammatory disease that affects tooth-supporting structures and in which dental plaque bacteria, immune mechanisms and genetic predisposition play important roles. Interleukin 4 (IL-4) is a key anti-inflammatory cytokine with relevant action in imbalances in inflamed periodontal tissue. Individuals carrying the TCI/CCI genotype (S-haplotype) of the IL-4 gene are 5 times more susceptible to CP, whereas the CTI/TTD genotype (P-haplotype) confers protection against CP. Compared with the S-haplotype, subjects with the P-haplotype produce higher levels of the IL-4 protein after non-surgical periodontal therapy. The present in vitro study aimed to investigate the functionality of IL-4 haplotypes in immune cells to obtain insight into the influence of these genetic variations in regulating immune responses to CP-associated bacteria. Peripheral blood was collected from 6 subjects carrying each haplotype, and their immune cells were challenged with periodontopathogens to compare responses of the different haplotypes with regard to gene expression, protein secretion and the immunophenotype of T helper responses. We found higher IL-4 mRNA and protein levels in the P-haplotype, which also presented higher levels of anti-inflammatory cytokines. In contrast, cells from S-haplotype subjects responded with higher levels of pro-inflammatory cytokines. S-haplotype individuals exhibited significantly greater polarization toward the Th1 phenotype, whereas the P-haplotype was associated with an attenuated response to periodontopathogens, with suggestive skewing toward Th2/M2 phenotypes. In conclusion, IL-4 genetic variations associated with susceptibility to or protection against chronic periodontitis are directly associated with influencing the response of immune cells to periodontopathogens.

Interaction of IL1B and IL1RN polymorphisms, smoking habit, gender, and ethnicity with aggressive and chronic periodontitis susceptibility

Background:

Although the interleukin-1 (IL-1) plays a critical role in the pathogenesis of periodontitis, associations between IL1 gene cluster polymorphisms and the disease remains unclear.

Aims:

To investigate the importance of IL1B-511C>T (rs16944), IL1B +3954C>T (rs1143634), and IL1RN intron 2 variable number tandem repeat (VNTR) (rs2234663) polymorphisms, individually or in combination, as the risk factors of periodontitis in a Southeastern Brazilian population with a high degree of miscegenation.

Subjects and Methods:

A total of 145 individuals, with aggressive (aggressive periodontitis [AgP], n = 43) and chronic (chronic periodontitis [CP], n = 52) periodontitis, and controls (n = 50) were genotyped by polymerase chain reaction (PCR) (IL1RN intron 2 VNTR) or PCR-restriction fragment length polymorphism (PCR-RFLP) (IL1B-511 C>T and IL1B + 3954C>T) techniques.

Statistical Analysis:

The independent t-test, Chi-square, and Fisher's exact tests were used. The SNPStats program was used for haplotype estimation and multiplicative interaction analyses.

Results:

The IL1B +3954T allele represented risk for CP (odds ratio [OR] = 2.84), particularly in smokers (OR = 4.43) and females (OR = 6.00). The minor alleles IL1RN*2 and *3 increased the risk of AgP (OR = 2.18), especially the IL1RN*2*2 genotype among  white Brazilians (OR = 7.80). Individuals with the combinations of the IL1B + 3954T and IL1RN*2 or *3-containing genotypes were at increased risk of developing CP (OR = 4.50). Considering the three polymorphisms (rs16944, rs1143634, and rs2234663), the haplotypes TC2 and CT1 represented risk for AgP (OR = 3.41) and CP (OR = 6.39), respectively.

Conclusions:

Our data suggest that the IL1B +3954C>T and IL1RN intron 2 VNTR polymorphisms are potential candidates for genetic biomarkers of periodontitis, particularly in specific groups of individuals.

Evaluation of ICAM-1 and VCAM-1 Gene Polymorphisms in Patients with Periodontal Disease

BACKGROUND We aimed to investigate the potential genetic relationships between the polymorphisms of gene rs5498 ICAM-1 and rs1041163 VCAM-1 and chronic periodontitis in a Chinese population within Heilongjiang. MATERIAL AND METHODS Genomic DNA was extracted from oral mucosa cells of 584 periodontal patients and 182 healthy individuals. Genotyping of the rs5498 ICAM-1 and rs1041163 VCAM-1 gene polymorphisms was performed with the Multiplex SNaPshot technique. RESULTS Statistically significant associations were identified between the chronic periodontal patients and the controls in the gene polymorphisms of rs5498 ICAM-1 (P=0.007) and rs1041163 VCAM-1 (P=0.029). The distribution of rs5498 (P=0.029) and rs1041163 (P=0.049) differed significantly across the mild, moderate, and severe groups of periodontitis. CONCLUSIONS Our findings indicate that ICAM-1 rs5498 and VCAM-1 rs1041163 polymorphisms contribute to chronic periodontitis, and ICAM-1 rs5498 and VCAM-1 rs1041163 gene polymorphisms might be associated with periodontitis severity in the Heilongjiang Chinese population. Further studies should be conducted to determine whether these polymorphisms could be used as biomarkers of periodontitis.

A meta-analysis of MMP-9 promoter -1562 C/T polymorphism on susceptibility of chronic periodontitis

Background

Although many studies have focused on the association of the MMP-9 promoter −1562 C/T polymorphism with the susceptibility and/or severity of chronic periodontitis (CP), results have been inconsistent. Therefore, a meta-analysis of all eligible studies was performed to derive a more precise estimation of the association between this polymorphism and CP risk.

Methods

All relevant studies were identified through a database search in PubMed, Medline, and Web of Science. All the full-text studies with appropriate analytical design, published in English, which evaluated the association of MMP-9 promoter −1562C/T polymorphism with CP risk using validated genotyping methods, and with non-duplicated data were selected for this study. A fixed-effect model was used to calculate pooled ORs in the absence of heterogeneity across included trials (P > 0.1 and I² < 50 %), otherwise the random-effect model was applied.

Results

In an overall meta-analysis, pooled ORs revealed that T variant in the MMP-9 promoter −1562 C/T polymorphism was associated with a significantly decreased risk for CP under all comparison models. In subgroup analyses by ethnicity, pooled ORs showed that a significant association of the MMP-9 promoter −1562 C/T polymorphism with CP risk was only detected in Caucasians and Asians but not in mixed population. In the subgroup analysis by severity of CP, pooled ORs indicated that T allele of the MMP-9 promoter −1562 C/T polymorphism was associated with decreased susceptibility to severe CP while there was no significant association between this polymorphism and moderate CP.

Conclusions

Our meta-analysis showed that T allele in the MMP-9 promoter −1562 C/T polymorphism might be a protective factor for CP, especially in Caucasians and Asians. Moreover, there was a significant association of the MMP-9 promoter −1562 C/T polymorphism with decreased susceptibility to severe CP, while the allelic and/or genotype distributions of this polymorphism were not associated with moderate CP.

Electronic supplementary material

The online version of this article (doi:10.1186/s40064-016-2135-3) contains supplementary material, which is available to authorized users.

Cellular Profile and Expression of Immunologic Markers in Chronic Apical Periodontitis from HIV-infected Patients Undergoing Highly Active Antiretroviral Therapy

INTRODUCTION

This study tested the hypothesis that the inflammatory cell profile (CD3-, CD4-, CD8-, CD20-, and CD68-positive cells) and the expression of immunologic markers (tumor necrosis factor α, interferon-γ, interleukin-6, and interleukin-18) in chronic apical periodontitis are the same between non-HIV-infected patients and HIV-infected patients undergoing highly active antiretroviral therapy (HAART).

METHODS

Thirty-four surgically excised chronic apical periodontitis lesions were sampled from 34 patients (17 HIV-infected and 17 non-HIV-infected). The lesions were extracted from teeth with no previous endodontic treatment. All HIV-infected patients were undergoing HAART. The specimens were submitted to histopathologic and immunohistochemical analyses by using an optical microscope. Immunoexpression was graded into 2 levels, focal to weak and moderate to strong. The χ(2), Fisher exact, and Mann-Whitney tests were used to analyze all significant differences between groups.

RESULTS

Periapical cysts represented 70.6% and 52.9% of the lesions in the HIV-infected and non-HIV-infected groups, respectively; however, no statistically significant difference was observed (P = .481). There were no statistically significant differences between groups for the inflammatory cell profile and for any of the immunologic markers (P > .05).

CONCLUSIONS

There are no statistically significant differences of the cellular profile and expression of immunologic markers in chronic apical periodontitis between non-HIV-infected patients and HIV-infected patients undergoing HAART.

TBX21-1993T/C (rs4794067) polymorphism is associated with increased risk of chronic periodontitis and increased T-bet expression in periodontal lesions, but does not significantly impact the IFN-g transcriptional level or the pattern of periodontophatic bacterial infection

Th1-polarized host response, mediated by IFN-γ, has been associated with increased severity of periodontal disease as well as control of periodontal infection. The functional polymorphism TBX21-1993T/C (rs4794067) increases the transcriptional activity of the TBX21 gene (essential for Th1 polarization) resulting in a predisposition to a Th-1 biased immune response. Thus, we conducted a case-control study, including a population of healthy controls (H, n = 218), chronic periodontitis (CP, n = 197), and chronic gingivitis patients (CG, n = 193), to investigate if genetic variations in TBX21 could impact the development of Th1 responses, and consequently influence the pattern of bacterial infection and periodontitis outcome. We observed that the polymorphic allele T was significantly enriched in the CP patients compared to CG subjects, while the H controls demonstrated and intermediate genotype. Also, investigating the putative functionality TBX21-1993T/C in the modulation of local response, we observed that the transcripts levels of T-bet, but not of IFN-γ, were upregulated in homozygote and heterozygote polymorphic subjects. In addition, TBX21-1993T/C did not influence the pattern of bacterial infection or the clinical parameters of disease severity, being the presence/absence of red complex bacteria the main factor associated with the disease status and the subrogate variable probing depth (PD) in the logistic regression analysis.

Association of susceptible genotypes to periodontal disease with the clinical outcome and tooth survival after non-surgical periodontal therapy: A systematic review and meta-analysis

Background

The real clinical utility of genetic testing is the prognostic value of genetic factors in the clinical outcome of periodontal treatment and the tooth survival. A meta-analysis was undertaken to estimate the effect of a susceptible genotype to periodontitis on the clinical outcomes of non-surgical periodontal therapy and the tooth survival.

Material and Methods

A systematic search of MEDLINE-Pubmed, Cochrane Library and Scopus was performed. Additionally, a hand search was done in three journals. No specific language restriction was applied. Two reviewers screened independently titles and abstracts or full text copies. Quality assessment of all the included studies was held.

Results

Initial screening of electronic databases resulted in 283 articles. Ten studies met the inclusion criteria, nine of them examined the clinical outcome, while the other one investigated the tooth survival in susceptible individuals after non-surgical periodontal therapy. Eight of included studies were selected for the meta-analysis. IL-1 positive genotypes increase the risk of tooth loss, while no association found between the bleeding on probing (BOP), clinical attachment loss (CAL) and plaque index (PI) with the genotype status. Probing pocket depth (PPD) reduction in the first three months and in long-term results found to have a significant association with the genotype.

Conclusions

There is no difference in the clinical measurements after non-surgical periodontal treatment, apart from PPD. More publications are needed to identify a cause-effect relationship.

Key words:Periodontal disease, periodontitis, periodontal therapy, clinical outcome, tooth loss, susceptibility, polymorphism, genotype, meta-analysis, systematic review.

A study of the periodontal state of a late Medieval United Kingdom population

OBJECTIVE

To study the severity of bone loss in a Medieval UK population, and compare this with other ancient UK populations from different time periods.

DESIGN

Skulls from a burial site in York (XI-XV century) were investigated. Skulls with a minimum of 17 teeth were included and were divided from childhood into five age groups. Direct measurements from the cement enamel junction (CEJ) to the alveolar crest (AC) were undertaken at six points around each tooth with a UNC 15 probe. The mean bone loss was calculated for each tooth type.

RESULTS

Seventy five skulls were included in the study (12-60 years of age). Bone loss was found to increase with age, but stabilized in older individuals (>45 years). The mean CEJ-AC distance varied from 2.1mm in the youngest group to a maximum of 4.1mm in 36-45 year olds. Results were compared with a Roman-British population (Whittaker et al., 1982) where comparable values for mean bone loss were 2.2mm and 5.4mm respectively, and a population of XVIII century Londoners (Whittaker et al., 1998) where bone loss of 1.1mm and 4.0mm was reported for the youngest and oldest age groups respectively.

CONCLUSION

Measuring the CEJ-AC distance in dried skulls from ancient populations may be used as a proxy for the levels of periodontal disease irrespective of tooth wear. The findings from the current study suggest that the severity of periodontitis as determined by measurements of alveolar bone loss on dried skulls from this ancient population, seems to have declined in the United Kingdom from the III-V century to XVIII century. This may be due to changes in environmental factors including living conditions and diet, together with individual characteristics including systemic illness and genetic make up.

Association of Fc gamma-receptors IIa, IIIa, and IIIb genetic polymorphism with susceptibility to chronic periodontitis in South Indian population

BACKGROUND AND OBJECTIVE

Fc gamma receptors (FcγRs) are the members of the immunoglobulin superfamily and may play a role in the pathogenesis of periodontitis. Genetic variation in these receptors and its link with various forms of periodontitis is being studied in different populations. The aim of the present study is to determine whether specific FcγRIIa, FcγRIIIa, and FcγRIIIb alleles and/or genotypes are associated with risk for susceptibility to generalized chronic periodontitis (GCP) in South Indian population.

MATERIALS AND METHODS

The study population consisted of 120 South Indian subjects; 60 with GCP and 60 periodontally healthy. Deoxyribonucleic acid (DNA) was extracted from samples collected by scrapping buccal epithelium. FcγRIIa and FcγRIIIa genotyping were performed by polymerase chain reaction (PCR) amplification of DNA with allele-specific primers followed by allele-specific restriction digestion of the products. However, FcγRIIIb genotyping was done by allele-specific PCR.

RESULTS

No significant difference in the distribution of FcγRIIa H/R and FcγRIIIa NA1/NA2 genotypes or their respective alleles was observed in GCP patients and healthy subjects. For FcγRIIIa F/V genetic polymorphism, the homozygous V/V genotype and V allele were significantly overrepresented in GCP patients while F/F genotype and F allele in controls.

CONCLUSION

The present study demonstrates that FcγRIIIa V/V genotype, as well as V allele, could be a possible risk factor for chronic periodontitis in South Indian population.

Relationship between Periodontitis and Rheumatoid Arthritis: Review of the Literature

Periodontitis (PD) and rheumatoid arthritis (RA) are immunoinflammatory diseases where leukocyte infiltration and inflammatory mediators induce alveolar bone loss, synovitis, and joint destruction, respectively. Thus, we reviewed the relationship between both diseases considering epidemiological aspects, mechanical periodontal treatment, inflammatory mediators, oral microbiota, and antibodies, using the keywords “periodontitis” and “rheumatoid arthritis” in PubMed database between January 2012 and March 2015, resulting in 162 articles. After critical reading based on titles and abstracts and following the inclusion and exclusion criteria, 26 articles were included. In the articles, women over 40 years old, smokers and nonsmokers, mainly constituted the analyzed groups. Eight studies broached the epidemiological relationship with PD and RA. Four trials demonstrated that the periodontal treatment influenced the severity of RA and periodontal clinical parameters. Nine studies were related with bacteria influence in the pathogenesis of RA and the presence of citrullinated proteins, autoantibodies, or rheumatoid factor in patients with PD and RA. Five studies investigated the presence of mediators of inflammation in PD and RA. In summary, the majority of the articles have confirmed that there is a correlation between PD and RA, since both disorders have characteristics in common and result from an imbalance in the immunoinflammatory response.

Interleukin-1β (3953/4) C→T polymorphism increases the risk of chronic periodontitis in Asians: evidence from a meta-analysis of 20 case-control studies

INTRODUCTION

To investigate the association of the interleukin-1β (IL-1β) (3953/4) C→T polymorphism with chronic periodontitis (CP) in Asians.

MATERIAL AND METHODS

Systematic searches of electronic databases and hand searching of references were performed, including PubMed, Embase, the Cochrane Library, and the Chinese National Knowledge Infrastructure (CNKI). Odds ratios (ORs) with 95% confidence intervals (CIs) were used to assess the strength of the associations. Publication bias was tested by Egger's test. Sensitivity analysis was conducted by limiting the meta-analysis studies conforming to Hardy-Weinberg equilibrium (HWE). Data analyses were carried out using RevMan 6.0.

RESULTS

A meta-analysis was performed on 20 published case-control studies, including 1,656 CP cases and 1,498 healthy controls. The pooled OR was 1.60 (95% CI = 1.02-2.52, p = 0.04) for the T allele carriers (TT + CT) compared with CC and 1.60 (95% CI = 1.06-2.42, p = 0.02) for T vs. C. Subgroup analysis by country revealed significant risks of CP among Indians carrying the T allele (TT vs. CC: OR = 3.88, 95% CI = 1.77-8.50, p = 0.0007).

CONCLUSIONS

The analysis showed that IL-1β (3953/4) C→T polymorphism probably increases the risk of CP in Asians, and the IL-1β+3954 TT genotype may be associated with a strongly increased risk of CP in Indians, but not in Chinese.

Cell adhesion proteins: roles in periodontal physiology and discovery by proteomics

Adhesion molecules expressed by periodontal connective tissue cells are involved in cell migration, matrix remodeling and inflammatory responses to infection. Currently, the processes by which the biologic activity of these molecules are appropriately regulated in time and space to preserve tissue homeostasis, and to control inflammatory responses and tissue regeneration, are not defined. As cell adhesions are heterogeneous, dynamic, contain a complex group of interacting molecules and are strongly influenced by the type of substrate to which they adhere, we focus on how cell adhesions in periodontal connective tissues contribute to information generation and processing that regulate periodontal structure and function. We also consider how proteomic methods can be applied to discover novel cell-adhesion proteins that could potentially contribute to the form and function of periodontal tissues.