Saliva microbiota and metabolite in individuals with caries or periodontitis / 中华口腔医学杂志

Objective: To detect and analyze the characteristics of oral microbiota in species composition, function and metabolism among caries, periodontitis and oral healthy individuals, hunting for the microbiome-derived biomarkers with specificity and sensitivity to estimate the occurrence of these two diseases. Methods: Saliva samples were collected from 10 patients with high caries risk [decayed-missing-filled teeth (DMFT)≥6, HC group] in Department of Endodontics, 10 patients with periodontitis of grade Ⅱ A-Ⅲ C (PG group) in Department of Periodontology and 10 oral healthy individuals (HH group) from School of Stomatology, The Fourth Military Medical University during from March 2022 to June 2022. A baseline examination was conducted on all participants, including their oral conditions of caries and periodontal health. Metagenomic sequencing (Illumina PE150 platform) and liquid chromatography-mass spectrometry were used to detect microorganisms and their metabolites in the samples respectively. The sequencing data were analyzed to obtain the information of microbial taxonomic composition, functional genes and metabolites in each group of samples. The basic oral conditions and saliva samples of subjects in each group were evaluated and collected by the same professional endodontist. Results: There were no significant difference in baseline characteristics such as age and sex among the subjects in each group (P>0.05). DMFT in HC group (9.0±1.7) was significantly higher than that in HH group (0) and PG group (0) (F=243.00, P<0.001). Sequencing data analysis showed that the taxonomic compositions of salivary microbiota in each group were mainly Firmicutes, Bacteroidetes, Proteobacteria, Actinobacteria and Fusobacteria at the phylum level, and Streptococcus, Neisseria, Rothia, Prevotella at the genus level. Differential analysis showed that, compared with the HH group, HC group and PG group had significant differences in taxonomic composition (P<0.05), and the most significant among them was Prevotella. At the species level, Prevotella pallens was the most significant change in HC group, and Porphyromonas gingivalis in PG group. Metabolite analysis showed that there were significant differences in metabolites between HC group and PG group. The results showed that, compared with the HH group, the most significant metabolite change was 3-hydroxy-1, 5-diphenylpentan-1-one in HC group (P=0.001) and N1 acetylspermine in PG group (P=0.002) respectively. Compared with the PG group, the metabolite of HC group with the most significant difference is D-glucosamine 6-phosphate (P=0.006). The metabolism gene function analysis showed that, the enrichment of carbohydrate metabolism related genes was highest in HC group, followed with HH group, and it was lowest in PG group. In addition, compared with the HH group, the abundance of functional genes related to glucose metabolism, such as ABC transporter and phosphotransferase system, were significantly decreased in PG group (P<0.05), but significantly increased in HC group (P<0.05). Conclusions: There is a significant correlation between the alternation of carbohydrate metabolism of salivary microbiota with the occurrence of caries and periodontitis. In the future, Prevotella pallens and 3-hydroxy-1, 5-diphenylpentan-1-one may be the potential biomarkers of caries; while Porphyromonas gingivalis and N1 acetylspermine work in the predictions of periodontitis.

Analysis of porphyromonas gingivalis fimA genotypes in severe periodontitis patients

Abstract The aim of this study was to i) evaluate the prevalence of P. gingivalis and the genotypes fim A I, Ib, II, III, IV, and V in Brazilian patients with periodontitis stage III and IV, grades B and C, ii) compare periodontitis grades B and C with regard to the prevalence of P. gingivalis and fim A genotypes, and iii) correlate the presence of these pathogens with clinical periodontal variables. Two samples of subgingival biofilm were collected from the interproximal sites with the greatest clinical attachment loss (CAL) of each patient (grade B = 38; grade C = 54) and submitted to polymerase chain reaction (PCR) for the identification of P. gingivalis and fim A genotypes. The collected periodontal clinical parameters included gingival index, plaque index, probing depth (PD), bleeding on probing (BoP) and CAL. P. gingivalis was present in 61.96% of the samples, but more prevalent in patients with grade C periodontitis (p = 0.048) and higher CAL (p < 0.001), PD (p < 0.001), and BoP (p = 0.01) values, and at sites with high CAL values (p = 0.01). The fim A II genotype was more prevalent in patients with greater mean PD (p = 0.04) and a higher proportion of bleeding sites (p = 0.006). Thus, in this sample of Brazilian periodontitis patients, the presence of P. gingivalis was associated with grade C periodontitis and periodontal destruction, while the fim A II genotype was associated with increased PD and BoP, supporting the notion that P. gingivalis fim A II is an important virulence factor in periodontal tissues.

Frequency of Porphyromonas gingivalis fimA in smokers and nonsmokers after periodontal therapy

Abstract Porphyromonas gingivalis is one of the most important Gram-negative anaerobe bacteria involved in the pathogenesis of periodontitis. P. gingivalis has an arsenal of specialized virulence factors that contribute to its pathogenicity. Among them, fimbriae play a role in the initial attachment and organization of biofilms. Different genotypes of fimA have been related to length of fimbriae and pathogenicity of the bacterium. Objectives The aim of this study was to identify 5 types of fimA genotype strains in smokers and nonsmokers with periodontitis, before and after periodontal therapy. Material and Methods Thirty-one patients with periodontitis harboring P. gingivalis were selected: 16 nonsmokers (NS) and 15 smokers (SM). Clinical and microbiological parameters were evaluated at baseline and 3 months after periodontal treatment, namely: plaque index, bleeding on probe, probing depth, gingival recession and clinical attachment level. The frequency of P. gingivalis and fimA genotype strains were determined by polymerase chain reaction. Results Type I fimA was detected in the majority of SM and NS at baseline, and the frequency did not diminish after 3 months of treatment. The frequency of type II genotype was higher in SM than NS at baseline. After 3 months, statistical reduction was observed only for types II and V fimA genotypes in SM. The highest association was found between types I and II at baseline for NS (37.5%) and SM (53.3%). Conclusion The most prevalent P. gingivalis fimA genotypes detected in periodontal and smoker patients were genotypes I and II. However, the presence of fimA genotype II was higher in SM. Periodontal treatment was effective in controlling periodontal disease and reducing type II and V P. gingivalis fimA.

The effects of different restorative materials on periodontopathogens in combined restorative-periodontal treatment

Abstract Objective The aim of the study was to evaluate the association between subgingival restorations and the target periodontopathogenic bacteria (Pg, Td and Pi) in subgingival biofilm during one year after combined restorative-periodontal treatment. Material and Methods Seventeen systemically healthy subjects, who were positive for the presence of three cervical lesions associated with gingival recessions in three different adjacent teeth, were included in the study. A total of 51 combined defects were treated with connective tissue graft plus a nanofilled composite resin (NCR+CTG), a resin-modified glass ionemer cement (RMGI+CTG) and a fluoride-releasing resin material with pre-reacted glass (PRG), called giomer (Giomer+CTG). Periodontal clinical measurements and subgingival plaque samples were obtained from all combined defects at baseline and at 6 and 12 months after the surgery. The number of bacteria were evaluated by the real-time polymerase chain reaction (qPCR) method. Results No statistically significant difference in the amount of DNA copies of Pg, Td and Pi was observed in any of the groups at any time points (p>0.05). In addition, there was no statistically significant difference in the amount of DNA copies of the bacteria at baseline and at 6 and 12 months postoperatively, regardless of treatment group (p>0.05). Conclusion This study suggests that subgingivally placed NCR, RMGI and giomer restorations can show similar effects on periodontopathogenic bacteria in the treatment of gingival recessions that are associated with noncarious cervical lesions (NCCLs).

Distribución gen fimA de Porphyromonas gingivalis en pacientes chilenos con periodontitis crónica / Distribution of fimA genotypes of Porphyromonas gingivalis in Chilean patients with chronic periodontitis

RESUMEN: Antecedentes: Gen fimA de Porphyromonas gingivalis es un importante factor de virulencia asociado al desarrollo y la progresión de periodontitis. Objetivo: Cuantificar los niveles de P. gingivalis y la prevalencia de genotipos fimA en pacientes chilenos con diferentes grados de severidad de periodontitis crónica. Metodología: Se analizaron 135 muestras subgingivales de 45 adultos (15 con leve, 15 con moderada y 15 con periodontitis severa) mediante qPCR para P. gingivalis y genotipos fimA (I-V and Ib). Resultados: Se detectó P. gingivalis en el 73,3% de los pacientes con periodontitis crónica (46,6%, 73,3% y 100% para las formas leve, moderada y severa, respectivamente). El gen fimA se detectó en el 66% de los sujetos positivos para P. gingivalis, siendo el fimA IV y I los genotipos más prevalentes. Además, se detectó fimA IV en el 75% y fimA I en el 62,5% de los casos severos y moderados de periodontitis, respectivamente. Los niveles aumentados de fimA IV se asociaron con periodontitis crónica severa. Conclusiones: Los resultados sugieren una alta prevalencia de P. gingivalis y de sus genotipos fimA IV y I en pacientes con periodontitis crónica. Además fimA IV fue asociado con formas más severas de periodontitis crónica en esta población chilena.

ABSTRACT: Background: Porphyromonas gingivalis fimA gene is a key virulence factor and has been associated with development and progression of periodontal diseases. Aim: To quantify the levels of P. gingivalis and the prevalence of fimA genotypes in Chilean patients with different severity of chronic periodontitis. Methodology: One hundred and thirty five subgingival samples from 45 adults (15 with slight, 15 with moderate and 15 with severe chronic periodontitis, respectively) were analyzed by qPCR for P. gingivalis and fimA genotypes (I-V and Ib). Results: P. gingivalis was detected in 73.3% of patients (46.6%, 73.3% and 100% of patients with slight, moderate and severe chronic periodontitis, respectively). The genotype fimA was detected in 66% of positive subjects for P. gingivalis, whereas fimA IV and I were the most prevalent genotypes. In addition, fimA IV was detected in 75% and fimA I in 62.5% of severe and moderate cases, respectively. Increased levels of fimA IV were associated with severe chronic periodontitis. Conclusions: These findings suggest that there is a high prevalence of P. gingivalis and its fimA IV and I genotypes in chronic periodontitis patients. Furthermore, fimA IV was associated with severe chronic periodontitis in this Chilean population.

Porphyromonas gingivalis Fim-A genotype distribution among Colombians / Distribución del genotipo Fim-A de Porphyromonas gingivalis entre la población colombiana

Introduction: Porphyromonas gingivalis is associated with periodontitis and exhibit a wide array of virulence factors, including fimbriae which is encoded by the FimA gene representing six known genotypes. Objetive: To identify FimA genotypes of P. gingivalis in subjects from Cali-Colombia, including the co-infection with Aggregatibacter actinomycetemcomitans, Treponema denticola, and Tannerella forsythia. Methods: Subgingival samples were collected from 151 people exhibiting diverse periodontal condition. The occurrence of P. gingivalis, FimA genotypes and other bacteria was determined by PCR. Results: Porphyromonas gingivalis was positive in 85 patients. Genotype FimA II was more prevalent without reach significant differences among study groups (54.3%), FimA IV was also prevalent in gingivitis (13.0%). A high correlation (p= 0.000) was found among P. gingivalis, T. denticola, and T. forsythia co-infection. The FimA II genotype correlated with concomitant detection of T. denticola and T. forsythia. Conclusions: Porphyromonas gingivalis was high even in the healthy group at the study population. A trend toward a greater frequency of FimA II genotype in patients with moderate and severe periodontitis was determined. The FimA II genotype was also associated with increased pocket depth, greater loss of attachment level, and patients co-infected with T. denticola and T. forsythia.

Introducción: Porphyromonas gingivalis es una bacteria asociada con la periodontitis. Expresa una amplia gama de factores de virulencia, incluyendo las fimbrias, las cuales están codificadas por el gen FimA que representa seis genotipos conocidos. Objetivo: Identificar los genotipos de FimA de P. gingivalis en pacientes de Cali - Colombia, incluyendo la co -infección con Aggregatibacter actinomycetemcomitans, Treponema denticola y Tannerella forsythia. Métodos: Se obtuvieron muestras subgingivales de 151 individuos con diferentes diagnósticos periodontales. La ocurrencia de P. gingivalis, los genotipos de FimA y otras bacterias se determinó por PCR. Resultados: Porphyromonas gingivalis fue positiva en 85 pacientes. El genotipo FimA II fue más prevalente, pero no hubo diferencias significativas entre los grupos de estudio (54.3%), FimA IV fue el más frecuente en la gingivitis (13.0%). Una alta correlación (p= 0.000) se encontró entre P. gingivalis , T. denticola y T. forsythia. El genotipo FimA II estuvo correlacionado con la detección de T. denticola y T. forsythia. Conclusiones: Porphyromonas gingivalis tuvo una alta frecuencia incluso en el grupo de individuos sanos. Se encontró una tendencia hacia una mayor frecuencia de FimA II en pacientes con periodontitis moderada y severa. El genotipo FimA II también se asoció con una mayor profundidad de la bolsa, una mayor pérdida de nivel de inserción, y con los pacientes en los que se detectó co-infección con T. denticola y T. forsythia.

Prevalencia de los genotipos fimA II y fimA IV de Porphyromonas gingivalis en un grupo de mujeres mexicanas con diabetes gestacional en la región centro de México / Prevalence of fimA II and fimA IV Porphyromonas gingivalis genotypes in a group of Mexican women with gestational diabetes in the central region of México

La diabetes gestacional (DG) es una de las complicaciones médicas que más frecuentemente afectan a las mujeres embarazadas; algunos autores reportan una prevalencia entre el 9,7 y el 13,9%. La DG puede ser causa de efectos adversos como: nacimiento pretérmino, macrosomia, nacimiento por cesárea, hiperbilirrubinemia, hipertensión gestacional, así como la predisposición de desarrollar posteriormente diabetes mellitus tipo 2 y síndrome metabólico. La literatura señala la asociación entre los microorganismos presentes en el biofilm subgingival, etiológicos de la inflamación de los tejidos de soporte dentarios y diabetes mellitus. Uno de estos microorganismos, Porphyromonas gingivalis, expresa, entre otros factores de virulencia, una proteína llamada fimbrilina, la cual presenta variaciones genotípicas relacionadas con su capacidad de inducción en la expresión de mediadores inflamatorios; los genotipos fimA II y fimA IV se consideran con mayor capacidad de virulencia y su presencia se ha asociado con la resistencia a la insulina. En este estudio analizamos la prevalencia de los genotipos fimA II y fimA IV en un grupo de mujeres mexicanas de la región central de México con DG, en mujeres con embarazo sin diabetes y mujeres sin embarazo y sin diabetes. Los resultados encontrados muestran una elevada presencia del genotipo fimA II en mujeres con DG (p < 0,05)

Gestational diabetes (GD) is one of the most common complications in pregnant women, with some authors reporting prevalence between 9.7% and 13.9%. GD can lead to the following adverse effects: preterm birth, macrosomia, cesarean birth, hyperbilirubinemia, gestational hypertension, and predisposition to later develop diabetes mellitus type 2 and metabolic syndrome. The literature shows an association between microorganisms in the subgingival biofilm, which produces inflammation of the dental support tissue, and diabetes mellitus. Porphyromonasgingivalis is one of these microorganisms, and among other virulence factors, it expresses a protein called fimbrilin which has genotypic variations related to its ability to induce expression of inflammatory mediators. Genotypes fimA II and fimA IV are considered to have a greater virulence and their presence has been associated with insulin resistance. An analysis is made on the prevalence of genotypes fimA II and fimA IV in a group of women in central region of Mexico with GD, pregnant women without diabetes, and non-pregnant women without diabetes. The results show an elevated presence of genotype fimA II in women with GD (P <.05)

Genotipificación de los genes rgpA y kgp que codifican para las gingipaínas de Porphyromonas gingivalis / Genotyping of rgpA and kgp genes encoding Pophyromonas gingivalis gingipains

Porphyromonas gingivalis es un microorganismo fuertemente asociado con la etiología de la periodontitis. Esta bacteria posee varios factores de virulencia, dentro de los que destacan las gingipaínas, debido a sus múltiples acciones relacionadas con la destrucción de la matriz extracelular del tejido conectivo periodontal, la modulación del sistema inmune del hospedero y la estimulación de la expresión de citoquinas pro-inflamatorias. Estas proteinasas tienen afinidades específicas siendo Arg-gingipaínas (RgpA y RgpB, codificadas por los genes rgpA y rgpB, respectivamente) y Lys-gingipaínas (Kgp, codificada por el gen kgp). Se ha descrito que existen polimorfismos en los genes que codifican para esta proteinasas. El objetivo del presente estudio fue describir la frecuencia de los genotipos identificados para los genes rgpA y kgp en aislados clínicos de P. gingivalis, obtenidos desde pacientes con periodontitis. Para ello se utilizó amplificación por PCR de los genes rgpA y kgp, seguido de análisis de restricción. De un total de 47 aislados provenientes de 4 individuos con periodontitis crónica y 2 con periodontitis agresiva, se genotipificaron 38 aislados para el gen rgpA, exhibiendo la totalidad de éstos el patrón electroforético A (100 por ciento). Para el gen kgp se genotipificaron 43 aislados, presentando 28 de ellos (65.2 por ciento) el perfil electroforético kgp-I y 15 aislados (34.8 por ciento) el perfil kgp-II. En los aislados provenientes de un individuo fue posible apreciar ambos genotipos descritos para el gen kgp. Los resultados indican un predominio del patrón electroforético A (rgpA) y que el genotipo kgp-I fue el más frecuentemente encontrado de los genotipos kgp.

Porphyromonas gingivalis is a microorganism strongly associated with the etiology of periodontitis. This periodontal bacterium possesses an array of virulence factors, among which gingipains have a key importance, being involved with extracellular matrix destruction of periodontal tissues, modulation of host immune response and stimulation in the production of pro-inflammatory cytokines by different types of cells. These proteinases have specific affinities, being Arg-gingipains (RgpA and RgpB, encoded by rgpA and rgpB genes, respectively) and Lys-gingipains (Kgp, encoded by the kgp gene). It has been described that there are polymorphisms in the genes encoding for gingipains. Therefore, the aim of the present study was to describe the frequency of rgpA and kgp genotypes in clinical isolates of P. gingivalis obtained from periodontitis patients. For determining the rgpA and kgp genotypes, we used PCR amplification and restriction analysis. From 47 isolates obtained from 4 individuals with chronic periodontitis and 2 subjects with aggressive periodontitis, 38 were typified for rgpA gene and all exhibited the electrophoretic pattern A (100 percent). For kgp gene, we characterized 43 isolates, 28 of them (65.2 percent) with the kgp-I electrophoretic profile and 15 isolates (34.8 percent) with the kgp-II profile. In the isolates belonging to one individual, we found both genotypes of kgp gene. The results indicate a clear predominance of the electrophoretic pattern A (for rgpA gene) and kgp-I genotype was the most frequently found of the kgp genotypes.

Analysis of the presence of pathogens which predict the risk of disease at peri-implant sites through polymerase chain reaction (PCR)

A presença dos ADN de Actinobacillus actinomycetemcomitans, Porphyromonas gingivalis e Prevotella intermedia em amostras coletadas de sulco periimplantar de 19 pacientes parcialmente desdentados foi analisada pela reação em cadeia da polimerase (PCR). Dentre esses 19 pacientes, dez apresentavam histórico de doença periodontal e nove não apresentavam antecedentes. Os resultados obtidos nesta análise foram relacionados com a profundidade do sulco periimplantar, o sangramento à sondagem e o provável risco de doença. Constatou-se que houve a amplificação do ADN das bactérias-alvo em sete amostras, sendo quatro de pacientes sem histórico de periodontopatia. Este resultado sugere que mesmo na ausência de sinais inflamatórios significantes, essa detecção qualitativa pode indicar risco de periimplantite, requerendo manutenção pós-operatória mais rigorosa.

DNA probe analysis in smoker and non smoker rapidly progressive periodontitis patients--a pilot study.

Smoking is one of the most significant risk factors in the development and further advancement of inflammatory periodontal disease. The bacteria A. actinomycetemcomitans, P. gingivalis and P. intermedius as indicated as the potential pathogens associated with periodontal disease. Since the bacteria mentioned as well as smoking are factors associated with periodontitis it is of importance to elucidate the interrelationship between these factors. The purpose of this study was to investigate the prevalence of A. actinomycetemcomitans, P. gingivalis and P. intermedius in subgingival plaque samples obtained form healthy and diseased sites of patients with rapidly progressive periodontitis who were smokers and non smokers along with other clinical parameters.