Genetic polymorphism of interleukins 6 and 17 correlated with apical periodontitis: A Cross-sectional study

Abstract Interleukins 6 and 17 act in bone resorption in the presence of infections of endodontic origin for host defense. Genetic polymorphisms may be associated with increased bone loss, represented by areas of large periapical lesions. This study aimed to verify the frequency of interleukin 6 and 17 gene polymorphism in patients with asymptomatic apical periodontitis or chronic apical abscess and to verify the existence of correlations between periapical lesion area with age, gender, and presence of the polymorphism, in the studied population, in the state of Pernambuco. A population consisting of thirty diagnosed individuals was included. The area of the lesions was measured in mm². Genomic DNA was extracted and genotyping was performed by Polymerase Chain Reaction Restriction Fragment Length Polymorphism for interleukin 6 (rs 1800795) and interleukin 17 (rs 2275913). Fisher's exact, chi-square, and odds ratio tests were used. A logistic regression analysis was also performed using sex, age, and the presence of polymorphism as covariates, in addition to linear regression to test the relationship between age and lesion area. All tests used a significance level of 0.05% (p ≤0.05%). There was no statistical significance in the occurrence of large areas of periapical lesions correlated with age, sex, and diagnosis, nor in the distribution of alleles in the polymorphism of interleukins 6 and 17 in the studied groups. The frequency of homozygous and heterozygous polymorphism was high. The polymorphism of these interleukins is not correlated with the increase in the areas of asymptomatic periapical inflammatory lesions.

Resumo As interleucinas 6 e 17 atuam na reabsorção óssea na presença de infecções de oriegem endodôntica para defesa do hospedeiro. Polimorfismos genéticos podem estar associados ao aumento da perda óssea, representada por áreas de lesões periapicais grandes. O objetivo deste estudo foi verificar a frequência do polimorfismo dos genes interleucina 6 e 17 em pacientes com periodontite apical assintomática ou abscesso apical crônico e verificar a existência de correlações entre área de lesão periapical com idade, sexo e presença do polimorfismo, na população estudada, no estado de Pernambuco. Foi incluída uma população constituída por trinta indivíduos diagnosticados. A áreas da lesões foram medidas em mm². O DNA genômico foi extraído e a genotipagem realizada por Polimorfismo de Comprimento de Fragmento de Restrição de Reação em Cadeia da Polimerase para interleucina 6 (rs 1800795) e interleucina 17 (rs 2275913). Os testes exato de Fisher, qui-quadrado e odds ratio foram utilizados. Uma análise de regressão logística também foi realizada usando sexo, idade e presença de polimorfismo como covariável, além de regressão linear para testar a relação da idade e área da lesão. Todos os testes utilizaram um nível de significância de 0,05% (p ≤0.05%). Não houve significância estatística na ocorrência das áreas grandes de lesões periapicais correlacionadas com idade, sexo e diagnóstico nem nas distribuições de alelos no polimorfismo das interleucinas 6 e 17 nos grupos estudados. A frequência de polimorfismo homozigoto e heterozigoto foi alta. O polimorfismo dessas interleucinas não está correlacionado ao aumento das áreas das lesões inflamatórias periapicais assintomáticas.

Effectiveness of the use of xylitol chewing gum in prevention of dental caries A systematic review

This systematic review of the literature assessed the effectiveness of using chewing gum containing only xylitol compared to prevention strategies or placebo in reducing the incidence of carious lesions in children using data obtained from randomized controlled trials. Electronic search was carried out in PubMed MEDLINE, Latin American and Caribbean Literature on the Health Science, Web of Science, Scopus, Science Direct, and Scientific Electronic Library Online through the period between 2000 and 2020. Included clinical studies were done in children when the xylitol was dispensed in gum and the preventive effect of xylitol on tooth decay was compared to other preventive strategies or control groups. The studies were evaluated for their quality to obtain the level of evidence. The preventive fraction of each study was extracted. Two hundred studies were found. After analyzing the inclusion and removal of duplicates, only five studies were analyzed for the quality of evidence. With the analysis through the Grading of Recommendations Assessment, Development, and Evaluation system, it was possible to verify the very low level of scientific evidence on the effectiveness of gums containing only xylitol for the prevention of caries in children. The preventive fraction obtained varied between ? 0.31 and 0.57 depending on the compared prevention strategy. The conflicting results, limitations, and inconsistencies of the studies allow us to establish that there is insufficient evidence to support the use of gums containing only xylitol for the prevention of caries in children. Other properly designed clinical trials need to be carried out.

Immunohistochemical expression of TGF-ß1 and MMP-9 in periapical lesions

Abstract The objective of this study was to evaluate the expression of matrix metalloproteinase 9 (MMP-9) and transforming growth factor beta (TGF-β1) in periapical lesion samples correlated with the intensity of the inflammatory infiltrate and thickness of the epithelial lining. Forty-five cases of periapical lesions (23 periapical granulomas and 22 radicular cysts) were subjected to morphological and immunohistochemical analyses using anti-MMP-9 and anti-TGF-β1 antibodies. The data were analyzed using the following tests: non-parametric Mann-Whitney, chi-square, Fisher's exact test and Spearman's correlation test (P<0.05). Analysis of inflammatory infiltrate revealed that 78% of periapical granulomas presented infiltrate grade III, in contrast with 32% of radicular cysts (P<0.001). Morphological evaluation of the epithelial thickness in radicular cysts revealed the presence of atrophic epithelium in 86% of the cysts. The immunostaining of MMP-9 was score 2 in 67% of the granulomas and 77% of the cysts. Both lesions were predominantly score 1 for TGF-β1. Significant differences were confirmed between the expression scores of TGF-β1 and MMP-9 in periapical granulomas (p = 0.004) and in radicular cysts (p < 0.001). Expression of TGF-β1 was different for periapical granulomas and radicular cysts. This immunoregulatory cytokine seems more representative in asymptomatic lesions. The extracellular matrix remodeling process dependent on MMP-9 seems to be similar for both periapical granulomas and radicular cysts. TGF-β1 and MMP-9 may play an important role in the maintenance of periapical lesions.