Efeitos do plasma frio sob pressão atmosférica como adjuvante no controle da periodontite experimental induzida por Aggregatibacter actinomycetemcomitans / Effect of atmospheric pressure cold plasma as adjuvante in the control of experimental periodontitis induced by Aggregatibacter actinomycetemcomitans

A etiopatogenia da doença periodontal é complexa e exige estudos constantes em alternativas terapêuticas que possibilitem seu controle. Aggregatibacter actinomycetemcomitans está associado fortemente à periodontite crônica e à periodontite agressiva. A tecnologia do plasma frio sob pressão atmosférica tem potencial para uso na odontologia, mas sua aplicação na periodontia ainda é pouco explorada. Este estudo teve como objetivo avaliar os efeitos do plasma de baixa temperatura sob pressão atmosférica (PBTPA) como adjuvante no controle da doença periodontal experimental induzida por ligadura, inoculada com A. actinomycetemcomitans, na região cervical do primeiro molar inferior em modelo murino. Inicialmente, foram determinados os parâmetros físicos efetivos para inibição de biofilmes de A. actinomycetemcomitans utilizando cepa padrão American Type Culture Collection ATCC 29523. Foram realizados testes de screening inicial com a verificação da inibição do crescimento por exposição ao PBTPA de A. actinomycetemcomitans semeados em placas de Petri. Posteriormente, foram formados biofilmes em placas de microtitulação e foram determinados os parâmetros físicos efetivos do PBTPA. Foram realizados experimentos in vivo de indução de doença periodontal por A. actinomycetemcomitans em modelo utilizando ligaduras em ratos. A tomografia computadorizada de feixe cônico foi utilizada para avaliar o nível de perda óssea após período experimental. Os resultados mostraram que o PBTPA foi efetivo na eliminação do micro-organismo observado através da formação de halos de inibição nos tempos de 5 e 7, 5 minutos e sobre biofilmes de A. actinomycetemcomitans expostos ao PBTPA no tempo de 5 minutos. Os resultados exibiram diferença estatística significativa (p <0,001) na distância entre a junção esmalte-cemento e a crista óssea alveolar, do grupo tratado com PBTPA em relação ao grupo raspagem e ao grupo controle. Os resultados do presente estudo sugerem o potencial do PBTPA no controle da periodontite induzida, contudo análises adicionais são necessárias(AU)

The etiopathogenesis of periodontal disease is complex requiring constant studies of therapeutic alternatives that enable its control. Aggregatibacter actinomycetemcomitans is strongly associated with chronic periodontitis and aggressive periodontitis. Cold plasma technology under atmospheric pressure has potential for use in dentistry, but its application in periodontics is still not well explored. This study aimed to evaluate the effects of low temperature atmospheric pressure plasma (PBTPA) as an adjuvant in the control of experimental periodontal disease induced by ligature inoculated with A. actinomycetemcomitans in the cervical region of the lower 1st molar in a murine model. Initially, effective physical parameters for inhibition of A. actinomycetemcomitans biofilms were determined using the standard strain American Type Culture Collection ATCC 29523. Initial screening tests were performed to verify growth inhibition after exposure of A. actinomycetemcomitans seeded in Petri dishes to the PBTPA. Subsequently, biofilms were formed on microtiter plates and the effective physical parameters of the PBTPA were determined. In vivo experiments were carried out to induce A. actinomycetemcomitans periodontal disease induced by ligature in a rat model. Cone beam computed tomography was used to assess the level of bone loss after the experimental period. The results showed that PBTPA was effective in eliminating the microorganism observed through the formation of halos inhibition during 5 and 7.5 minutes and in A. actinomycetemcomitans biofilms exposed to PBTPA at 5 minutes. The previous study using PBTPA in 5 minutes did not show cytotoxicity in Vero cells. The results showed a statistically significant difference (p <0.0001) in the distance between the enamel-cement joint and the alveolar bone crest, of the group treated with PBTPA in relation to the scalling group and the control group, confirming the potential of the technique in dentistry(AU)

Salivary markers of oxidative stress and periodontal pathogens in patients with periodontitis from Santander, Colombia / Marcadores salivales de estrés oxidativo y agentes patógenos periodontales en pacientes con periodontitis en Santander, Colombia

Introduction: Periodontitis affects more than 20% of the Latin American population. Oxidative markers are associated with greater progression of periodontitis; therefore, its role in pathogenesis should be studied. Objective: To determine the prevalence of the main oral bacteria and viruses associated with periodontitis and estimate the total antioxidant capacity and lipid peroxidation in saliva from patients with periodontitis. Materials and methods: We conducted systemically a cross-sectional study in 101 healthy subjects, 87 of whom had been diagnosed with periodontitis (P), according to the criteria of the Centers of Disease Control and Prevention and the American Academy of Periodontology, and 14 without periodontal pockets as controls (C). In subgingival samples, major viruses and dental pathogenic bacteria were identified using PCR techniques. The levels of total antioxidant capacity and malon-di-aldehyde (MDA) were determined by spectrophotometry in samples of unstimulated saliva. Results: The mean of periodontal depth pocket and clinical attachment loss in patients with periodontitis was 5.6 ± 1.7 and 6.1 ± 3.1 mm, respectively. The most prevalent microorganisms were Aggregatibacter actinomycetemcomitans (32.5%) and Porphyromonas gingivalis (18.6%). The patients from rural areas showed a higher percentage of A . actinomycetemcomitans (urban: 17.9% vs. rural: 48.9%, p=0.0018). In patients with periodontitis, the frequency of EBV, HSV1 & 2, and HCMV genes was 2.3%. Periodontitis patients had higher levels of MDA (P: 2.1 ± 1.5; C: 0.46 ± 0.3 µmol/g protein; p=0.0001) and total antioxidant capacity (P: 0.32 ± 0.2; C: 0.15 ± 0.1 mM; p< 0.0036). Oxidative markers showed no modifications due to the presence of periodontopathic bacteria. Conclusions: Aggregatibacter actinomycetemcomitans was the most prevalent bacteria; its presence did not modify the levels of oxidative markers in the saliva of patients with periodontitis.

Introducción. La periodontitis afecta a más del 20 % de la población latinoamericana. La presencia de marcadores de estrés oxidativo se asocia con una mayor progresión de periodontitis, por lo que su rol en la patogenia debe estudiarse. Objetivo. Determinar la prevalencia de las principales bacterias y virus asociados con la periodontitis y estimar la capacidad antioxidante total y la peroxidación de lípidos en la saliva de los pacientes con periodontitis. Materiales y métodos. Se hizo un estudio transversal en 87 sujetos sanos diagnosticados con periodontitis (P) según los criterios de los Centers of Disease Control and Prevention y la American Academy of Periodontology y 14 sujetos sin enfermedad periodontal como grupo control (C). En las muestras subgingivales se identificaron los principales virus y bacterias mediante técnicas de PCR. Los niveles de capacidad antioxidante total y malon-di-aldehído (MDA) se establecieron mediante espectrofotometría en muestras de saliva no estimulada. Resultados. Las medias de profundidad del sondaje y del nivel de inserción clínico periodontal en pacientes con periodontitis fueron 5,6 ± 1,7 y 6,1 ± 3,1 mm, respectivamente. Los microorganismos más prevalentes fueron Aggregatibacter actinomycetemcomitans (32,5 %) y Porphyromonas gingivalis (18,6 %). Los pacientes de áreas rurales registraron un mayor porcentaje de A. actinomycetemcomitans (urbano: 17,9 % Vs. rural: 48,9 %; p=0,0018). La frecuencia de los genes EBV, HSV1 y 2, y HCMV fue de 2,3 %. En pacientes con periodontitis se evidenciaron mayores niveles de MDA (P: 2,1 ± 1,5; C: 0,46 ± 0,3 µmol/g proteína; p=0,0001) y capacidad antioxidante total (P: 0,32 ± 0,2; C: 0,15 ± 0,1 mM; p<0,0036). La presencia de bacterias periodontales patógenas no modificó los marcadores oxidativos. Conclusiones.Aggregatibacter actinomycetemcomitans fue el agente patógeno mas prevalente. Su presencia no modificó los niveles de marcadores oxidativos en la saliva de los pacientes con periodontitis.

Essential Oil from Psidium cattleianum Sabine (Myrtaceae) Fresh Leaves: Chemical Characterization and in vitro Antibacterial Activity Against Endodontic Pathogens

Abstract Endodontic infections result from oral pathogenic bacteria which reach and infect dental pulp, as well as surrounding tissues, through cracks, unrepaired caries and failed caries restorations. This study aims to determine the chemical composition of essential oil from Psidium cattleianum leaves (PC-EO) and to assess its antibacterial activity against endodontic bacteria. Antibacterial activity of PC-EO was evaluated in terms of its minimum inhibitory concentration (MIC) values by the broth microdilution method on 96-well microplates. Bacteria Porphyromonas gingivalis (MIC = 20 µg/mL), Prevotella nigrescens (MIC = 62.5 µg/mL), Fusobacterium nucleatum (MIC = 12.5 µg/mL), Actinomyces naeslundii (MIC = 50 µg/mL), Bacteroides fragilis (MIC = 12.5 µg/mL), Aggregatibacter actinomycetemcomitans (MIC = 6.25 µg/mL) and Peptostreptococcus anaerobius (MIC = 62.5 µg/mL) were evaluated and compared to chlorhexidine dihydrochloride (CDH), the positive control. PC-EO was obtained by hydrodistillation with the use of a Clevenger-type apparatus whereas its chemical composition was analyzed by gas chromatography-flame ionization detection (GC-FID) and gas chromatography-mass spectrometry (GC-MS). Viridiflorol (17.9%), β-caryophyllene (11.8%), 1,8-cineole (10.8%) and β-selinene (8.6%) were the major constituents found in PC-EO, which exhibited high antibacterial activity against all endodontic pathogens under investigation. Therefore, PC-EO, a promising source of bioactive compounds, may provide therapeutic solutions for the field of endodontics.

Research progress of correlation between periodontal pathogens and systemic diseases / 南方医科大学学报

Periodontal pathogens are the main pathogenic factor of periodontitis. Periodontal pathogens have a large variety of virulence factors such as lipopolysaccharide, fimbriae and proteases, which enables the pathogens to infect periodontal tissues and stimulate the secretion of inflammatory cytokines, causing chronic systemic inflammation. Periodontal pathogens may invade multiple systems such as the circulatory system, immune system, respiratory system and digestive system to cause systematic diseases. Recent studies have shown that periodontal pathogens may have close relations with systemic diseases such as cardiovascular disease, diabetes, rheumatoid arthritis, and cancer. Among the periodontal pathogens, can be found in atherosclerotic plaques to impairing the function of the vascular endothelium; may also increase the level of inflammatory factors such as TNF-α to promote insulin resistance and diabetes. Many of the periodontal pathogens such as , and can be detected in the synovial fluid of rheumatoid arthritis patients, suggesting their involvement in the pathogenesis of rheumatoid arthritis. may cause alterations in the intestinal microbiome in mice and promote the occurrence of intestinal tumors. Herein we review the recent progresses in the relationship between periodontal pathogens and systemic diseases.

Porphyromonas gingivalis ligada a enfermedad periodontal y su relación con la artritis reumatoide: identificación de nuevos mecanismos biomoleculares / Porphyromonas gingivalis linked to periodontal disease and its relationship with rheumatoid arthritis: Identification of new biomolecular mechanisms

Objective: Review the existing scientific literature regarding the pathogenicity of Porphyromonas gingivalis, linked to periodontal disease (PD) (oral dysbiosis), and its association with the activation of pathophysiological mechanisms of rheumatoid arthritis (RA), in order to expose the new mechanisms biomolecular involved. Methods: Systematic search in the MeSH, pubmed, Science Direct, Nature y Google academic database, using the keywords: Aggregatibacter actinomycetemcomitans; rheumatoid arthritis; citrullination; dysbiosis; dentistry; periodontitis; porphyromonas gingivalis; rheumatology. Out of a total of 297 publications, 52 were selected, all from 2018; based on the inclusion and exclusion criteria established by the authors. Results: Pg infection linked to periodontal disease is strongly implicated in the pathogenesis and development of RA. Their relationship is linked to the citrullination process and production of citrullinated antipeptide antibodies. Associations have been identified between the microbial virulence of this agent and the expression of multiple genes related to the activation of the immune response and the onset of the chronic inflammatory process. Conclusions: There is a high association between the pathogenesis of both diseases, where microorganisms linked to PD such as Pg have the ability to increase citrullination, galactosylation, fucosylation, as well as excessive glycosylation of fragments antigen-binding (Fab), and therefore the aggressiveness of RA.

Objetivo: revisar la literatura científica existente con respecto a la patogenicidad de Porphyromonas gingivalis, ligada a enfermedad periodontal (EP) (disbiosis oral), y su asociación con la activación de mecanismos fisiopatológicos en la artritis reumatoide (AR), a fin de exponer los nuevos mecanismos biomoleculares implicados. Métodos: búsqueda sistemática en la base de datos del Medical Subject Headings (MeSH), PubMed, Science Direct, Nature y Google académico usando las palabras clave: Aggregatibacter actinomycetemcomitans; artritis reumatoide; citrulinación; disbiosis; odontología; periodontitis; Porphyromonas gingivalis y reumatología. De un total de 297 publicaciones, se seleccionaron 52, todas a partir del año 2018; la selección fue hecha a partir de los criterios de inclusión y exclusión establecidos por los autores. Resultados: la infección por Porphyromonas gingivalis, ligada a la EP, está fuertemente implicada en la patogénesis y desarrollo de AR. Su relación se vincula con el proceso de citrulinación y producción de anticuerpos antipéptidos citrulinados. Se han identificado asociaciones entre la virulencia microbiana de dicho agente y la expresión de múltiples genes, relacionados con la activación de la respuesta inmune y el inicio del proceso inflamatorio crónico. Conclusiones: existe una alta asociación entre la patogenia de ambas enfermedades, donde microorganismos ligados a la EP, como Porphyromonas gingivalis, tienen la capacidad de aumentar la citrulinación, galactosilación, fucosilación, así como la excesiva glicosilación de Fragmentos de unión al antígeno (Fab), y por lo tanto, la agresividad de la AR.

Clinical and microbiological evaluation of non-surgical periodontal therapy in obese and non-obese individuals with periodontitis: a 9-month prospective longitudinal study

Abstract Objective Obesity is a chronic disease that negatively affects an individual's general and oral health. The present study aimed to compare the clinical and microbiological effects of non-surgical periodontal therapy with the full mouth disinfection (FMD) protocol on obese and non-obese individuals at 9 months post-therapy. Methodology This clinical study was first submitted and approved by the Ethics Committee. Fifty-five obese patients and 39 non-obese patients with periodontitis were evaluated. The full-mouth periodontal clinical parameters, clinical attachment level (CAL), probing depth (PD), gingival index (GI), and plaque index (PI), were monitored at baseline, 3, 6, and 9 months after periodontal treatment with full mouth disinfection (FMD) protocol. The mean count of Tannerella forsythia , Porphyromonas gingivalis , Treponema Denticola , and Aggregatibacter actinomycetemcomitans was determined by quantitative polymerase chain reaction on subgingival biofilm samples. Demographic data were assessed by Chi-square test. For clinical and microbiological parameters, two-factor repeated-measures ANOVA was used. Results In both groups, periodontal therapy using the one-stage full-mouth disinfection protocol significantly improved CAL, PD, GI, and PI (p<0.05). Obese and non-obese patients equally responded to non-surgical periodontal therapy (p>0.05). Microbial count found no major differences (p>0.05) between obese and non-obese individuals who had undergone non-surgical periodontal therapy. Conclusions Obesity did not affect the clinical and microbiological outcomes of non-surgical periodontal therapy.

Microbiological study of the subgingival biofilm in HIV+/HAART patients at a specialized dental service / Estudio microbiológico del biofilm subgingival de pacientes VIH+ bajo TARGA en un servicio dental especializado

ABSTRACT The aim of this study was to describe the microbiological profile of HIV patients under highly active antiretroviral treatment (HAART). This crosssectional study comprised 32 HIV patients with periodontal disease (PD) who had been under HAART for more than 6 months. Information about the patients' medical history was obtained from clinical records. Clinical dental examination was performed by a calibrated researcher using standard dental instruments to determine probing depth (PD), clinical attachment level (CAL), and bleeding on probing (BOP). A total 4,765 periodontal sites were evaluated, 125 of which were also studied microbiologically. Subgingival biofilm samples were obtained using sterile paper points; one set was used for microbiological culture studies and the other for endpoint PCR. Statistical analysis was performed using KruskalWallis and posthoc DunnBonferroni contrast tests. All participants were on HAART at the time of the study, and 90.6% had a viral load below 50 copies/mm3. Prevalence of periodontally active sites was low in the study population. Microbiological studies: Black pigmented anaerobic bacteria and fusiform CFU counts were significantly higher in samples from sites with BOP and PD ≥4mm (p 0.020 and p 0.005, respectively). Molecular Assays: Detection of Porphyromonas gingivalis (p 0.002), Tannerella forsythia (p 0.023) and Treponema denticola (p 0.015) was significantly more frequent at sites with BOP and PD ≥4mm. Conclusions: The patients living with HIV/AIDS under HAART studied here had low prevalence of clinical periodontal disease signs. However, significant detection of P. gingivalis, T. denticola, and T. forsythia in periodontal active sites, and the involvement of these microorganisms as potential HIV reactivators, show the importance of creating awareness among dental health professionals of the need for close dental and periodontal monitoring in HIV patients.

RESUMEN El objetivo de este estudio fue describir el perfil microbiológico del biofilm subgingival de los pacientes con VIH bajo tratamiento antirretroviral de alta actividad (TARGA). El estudio comprendió a 32 pacientes VIH seropositivos con enfermedad periodontal (EP) que se encontraran en tratamiento con TARGA por más de 6 meses. Los antecedentes médicos de los pacientes se obtuvieron de las historias clínicas. El examen clínico instrumental (profun didad de sondaje (PS), nivel de inserción clínico (NIC) y sangrado al sondaje (SS)) fue realizado con instrumental odontológico estándar por un investigador calibrado. De este modo, se evaluaron un total de 4.765 sitios periodontales de los cuales 125 fueron estudiados microbiológicamente. Las muestras de biope lícula subgingival se obtuvieron empleando conos de papel estéril. Las muestras se emplearon en estudios microbiológicos y moleculares por PCR de punto final. El análisis estadístico se realizó según KruskalWallis y pruebas de contrastes posthoc de DunnBonferroni. El 90,6% de la población en estudio presentó carga viral inferior a 50 copias/mm3. La prevalencia de sitios periodontales activos fue baja (1%). Los recuentos de bacterias anaerobias estrictas pigmentadas de negro y fusiformes fueron significativamente más altos en muestras de sitios periodontales con SS positivo y PS ≥4 mm (p 0.020 y p 0.005). La detección molecular de Porphyromonas gingivalis (p 0.002), Tannerella forsythia (p 0.023) y Treponema denticola (p 0.015) fue significativamente mayor en los sitios con SS y PS ≥4mm. La prevalencia del 1% de enfermedad periodontal en el grupo de pacientes estudiados fue menor a la esperada, sin embargo; la detección significativa de P. gingivalis, T. denticola y T. forsythia en sitios periodontales activos y su potencial participación como agentes reactivadores del VIH, nos alerta de la importancia de crear conciencia en los profesionales de la salud (médicos y odontólogos) acerca de la necesidad de un monitoreo minucioso del estado periodontal de pacientes con características semejantes a las descriptas en la muestra poblacional estudiada.

Clinical and microbiological evaluation of surgical and nonsurgical treatment of aggressive periodontitis

Abstract The present study aimed to evaluate clinical and microbiological effects of surgical and nonsurgical periodontal therapy in generalized aggressive periodontitis (GAgP) treatment. Sixteen GAgP patients were included in this randomized split-mouth design clinical trial. Maxillary quadrants were allocated into two groups: Nonsurgical Therapy (NST) and Surgical Therapy (ST). The following clinical parameters were assessed: plaque index (PI), bleeding on probing index (BoP), probing depth (PD), clinical attachment level (CAL) and gingival margin position (GMP). Concentrations of Porphyromonas gingivalis (Pg) and Aggregatibacter actinomycetemcomitans (Aa) in the subgingival biofilm were also determined. Clinical and microbiological parameters were assessed at baseline (n=16), 3 (n=15), 6 (n=15) and 12 months (n=8) after treatment. ST was able to promote higher PD reduction compared to NST in deep pockets at 12 months (p<0.05) and in posterior teeth at 6 months (p<0.05). In addition, higher gingival recession was observed in posterior teeth of the ST group at the 6th month (p<0.05). However, ST failed to promoted additional CAL gain in any timepoint (p>0.05). Moreover, microbiological evaluation showed no statistical difference in levels of Aa and Pg for both groups at all follow-up periods. Surgical therapy promoted similar clinical benefits to GAgP therapy. Moreover, both therapies failed to reduce Aa and Pg levels at different follow-up times.

Resumo O presente estudo teve como objetivo avaliar os efeitos clínicos e microbiológicos de terapia periodontal cirúrgica e não cirúrgica no tratamento da periodontite agressiva generalizada (PAgG). Dezesseis pacientes portadores de PAgG foram incluídos neste estudo clínico, prospectivo, randomizado, de boca dividida. Os quadrantes superiores de cada paciente foram alocados em dois grupos: um grupo de terapia não-cirúrgica (NST) e um grupo de terapia cirúrgica (ST). Os parâmetros clínicos avaliados foram: índice de placa (PI), sangramento à sondagem índice (BoP), profundidade de sondagem (PD), nível clínico de inserção (CAL) e posição da margem gengival (GMP). Também foram determinadas as concentrações de Porphyromonas gingivalis (Pg) e Aggregatibacter actinomycetemcomitans (Aa) no biofilme subgengival. Os parâmetros clínicos e microbiológicos foram avaliados no início, 3, 6 e 12 meses após o tratamento. A terapia cirúrgica foi capaz de promover maior redução de PD em comparação com NST em bolsas profundas aos 12 meses (p<0,05) e em dentes posteriores aos 6 meses (p<0,05). Além disso, houve maior recessão gengival nos dentes posteriores do grupo ST no 6° mês (p<0,05). Entretanto, ST não promoveu ganho adicionais de inserção (CAL) em nenhum período do avaliação. A avaliação microbiológica não mostrou diferença estatística nos níveis de Aa e Pg, para ambos os grupos, em todos os períodos de acompanhamento. O tratamento cirúrgico promoveu benefícios clínicos similares ao tratamento não cirúrgico em pacientes com PAgG. Além disso, ambas as terapias não conseguiram reduzir os níveis Aa e Pg após terapia.

Endocardite infecciosa por aggregatibacter actinomycetemcomitans em pacientes predispostos / Infective endocarditis by aggregatibacter actionomycetemcomitans in predisposed patients

A endocardite infecciosa (EI) corresponde a uma infecção microbiana do endocárdio com presença de coágulo de plaquetas e fibrina em seu interior. Quando é de origem periodontal, a Aggregatibacter actinomycetemcomitans (Aa) é a bactéria mais relacionada com a ocorrência dessa doença. Foi avaliada a presença de Aa em gengivites e periodontites de pacientes hospitalizados e sua associação na predisposição à EI. Métodos: Realizou-se a sondagem periodontal em 15 pacientes de um hospital de Itajaí, SC com gengivites e periodontites, entre 18 a 75 anos de idade, de ambos os sexos, considerados em risco de EI. Usou-se um dente de cada paciente como amostra, coletado em cones de papel esterilizado, transferência em recipientes e processamento no laboratório. As amostras foram homogeneizadas e alíquotas de 0,1 ml foram semeadas em duplicata em placas de ágar sangue, incubadas por cinco dias em microaerofilia a 37 O C. Depois da visualização das colônias bacterianas características, foram realizadas provas bioquímicas e reação de catalase. O diagnóstico de EI foi realizado seguindo os critérios de Duke modificado. Conclusão: Não houve incidência de pacientes com risco de EI relacionada com presença da Aa nos participantes avaliados

Objective: Infective endocarditis (IE) corresponds to a microbial infection of the endocardium with the presence of platelet and fibrin clotting in its interior. When it is of periodontal origin, Aggregatibacter actinomycetemcomitans (Aa) is the bacterium most often related to the occurrence of this disease. The presence of Aa in the gingivitis and periodontitis of hospitalized patients and its association with predisposition to IE were evaluated. Methods: Periodontal probing was performed in 15 patients with gingivitis and periodontitis, aged 18 and 75 years, of both genders, and considered at risk for IE at a hospital in Itajaí ­ SC. One tooth of each patient was used for the sample, which was collected in cones of sterilized paper, transferred in containers, and processed in the laboratory. The samples were homogenized and aliquots of 0.1 ml were seeded in duplicate in blood agar plates, incubated for five days in microaerophylia at 37ºC. Following visualization of characteristic bacterial colonies, biochemical and catalase reaction tests were conducted. The diagnosis of IE was performed following the modified Duke criteria. Conclusion: There was no incidence of patients at risk of IE related to the presence of Aa in the participants evaluated

Periodontitis and periodontopathogens in individuals hospitalized in the intensive care unit: a case-control study

Abstract The aim of the present study was to compare periodontal conditions between intensive care unit (ICU) in-patients and non-ICU patients through clinical and microbiological periodontal parameters. This case-control study included 88 individuals hospitalized in ICU and 176 non-hospitalized controls. All individuals underwent a complete periodontal examination and microbiological sampling. The total bacterial load and counts of Porphyromonas gingivalis, Treponema denticola and Aggregatibacter actinomycetemcomitans were evaluated using qPCR. Data were analyzed through the Chi-square, Fisher exact, and t-Student tests, and the Spearman correlation, as appropriate. The prevalence of periodontitis was 39.7% among controls and 59.0% among ICU in-patients (OR=2.18; p=0.002). ICU in-patients had a significantly higher occurrence of cardiovascular disease (p=0.002; OR=2.20) and history of periodontal disease (p=0.031; OR=1.92) than controls. Bacterial counts of A. actinomycetemcomitans, T. denticola and P. gingivalis were significantly higher in ICU in-patients with periodontitis than in controls. The correlation between periodontal parameters and microbiological findings among cases and controls showed a significant and positive correlation between: total bacteria load and % of sites with probing depth (PD) ≥ 4 mm (cases: r=0.22 and controls: r=0.13) and P. gingivalis and % sites with bleeding on probing (BOP) (cases: r=0.22 and controls: r=0.23). Thus, ICU in-patients presented a higher prevalence of periodontitis and worse periodontal condition (higher mean plaque index, BOP, clinical attachment level ≥3 mm, and sites with PD 4 to 6 mm).

Resumo O objetivo deste estudo foi comparar as condição periodontais entre pacientes internados em Unidade de terapia intensiva (UTI) e indivíduos não hospitalizados através de parâmetros periodontais clínicos e microbiológicos. Este estudo caso-controle incluiu 88 indivíduos hospitalizados em UTI e 176 controles não hospitalizados. Todos os indivíduos foram submetidos a um exame periodontal completo e amostragem microbiológica. A carga bacteriana total e as contagens de Porphyromonas gingivalis, Treponema denticola e Aggregatibacter actinomycetemcomitans foram avaliadas utilizando qPCR. Os dados foram analisados, conforme apropriado, por meio dos testes de Qui-quadrado, Fisher exato, t-Student, Mann-Whitney e correlação de Spearman. A prevalência de periodontite foi de 39,7% entre os controles e de 59,0% entre pacientes internados em UTI (OR=2,18, IC 95%: 1,29-3,68; p=0,002). Pacientes admitidos na UTI apresentram significativamente uma maior ocorrência de doença cardiovascular (p=0,002, OR=2,20) e história de doença periodontal (p=0,031; OR=1,92) do que os controles. As contagens bacterianas de A. actinomycetemcomitans, T. denticola e P. gingivalis foram significativamente maiores nos pacientes em UTI com periodontite do que nos controles. A correlação entre os parâmetros clínicos periodontais e os achados microbiológicos entre casos e controles mostrou correlação significativa e positiva entre: carga bacteriana total e % de sítios com profundidade de sondagem (PS) ≥4 mm (casos: r=0,22 e controles: r=0,13) e P. gingivalis e % de sítios com sangramento à sondagem (SS) (casos: r=0,22 e controles: r=0,23). Pacientes internados na UTI apresentaram maior prevalência de periodontite e pior condição periodontal (maior média de índice de placa, SS, de sítios com nível de inserção clínica ≥ 3mm e PS de 4 a 6 mm) do que os controles.

Antibacterial Activity of Homeopathic Medications Lycopodium clavatum and Arsenicum album Against Periodontal Bacteria / Evaluación antibacteriana de los medicamentos homeopáticos sobre bacterias periodontales

Abstract There are several controversies regarding the efficacy of homeopathic substances; however, these remedies are used in many countries for the treatment of various pathological conditions. The purpose of this study was to evaluate the in vitro antibacterial activity of two homeopathic tinctures Arsenicum album (mineral extract) and Lycopodium clavatum (plant extract) on the periodontal bacteria Actinomyces israelii, Streptococcus sanguinis, Prevotella intermedia, Aggregatibacter actinomycetemcomitans and Phorphyromonas gingivalis (P. gingivalis). Materials and methods: Equal numbers of bacteria were seeded on agar plates containing enriched media with the homeopathic solutions at 1dH and 1cH dilutions. After 7 days of incubation under anaerobic conditions, colony forming units (CFUs) were counted. The antibacterial effect was calculated based on the total number of CFUs observed on non-tincture containing agar, and on the tincture containing plates. Results: No visible growth of any of the strains was observed on the plates containing Arsenicum album at any of the dilutions tested. In contrast, when Lycopodium clavatum at 1cH dilution was tested, only P. gingivalis was susceptible to this compound. Conclusions: The results suggest that the mineral extract tincture had a greater antibacterial activity than the plant extract tincture, also Lycopodium clavatum preparation could be an effective inhibitor of periodontal pathogens bacteria such as P. gingivalis.

Resumen Se necesita un mayor número de estudios in vitro e in vivo para validar estos resultados.

Diagnóstico molecular de microorganismos periodontopatógenos en pacientes alcohó-licos - fumadores con periodontitis crónica de la ciudad de Loja, Ecuador / Diagnóstico molecular de microrganismos periodontopatogênicos em pacientes taba-gistas com periodontite crônica na cidade de Loja, Equador / Molecular diagnosis of microorganisms periodontopathogens in alcoholic - smoking patients with chronic periodontitis of the city of Loja, Ecuador

Los pacientes alcohólicos y fumadores presentan mayor predisposición de desarrollar enfermedad periodontal. Objetivo: Determinar la presencia de los microorganismos periodontopatógenos: Porphyromona gingivalis, Treponema denticola, Tannerella forsythia, Fusobacterium nucleatum y Aggregatibacter actinomycetemcomitans mediante la Reacción en Ca-dena de la Polimerasa (PCR), en pacientes alcohólicos fumadores con periodontitis crónica. Materiales y métodos: El universo fue de 31 pacientes de 18 y 62 años de edad de sexo masculino alcohólicos y/o fumadores en los cuales fueron excluidos aquellos que consumían algún tipo de droga, dando una muestra de 23 pacientes con bolsas periodontales ≥ 6mm del Centro de Rehabilitación de la ciudad de Loja, Ecuador. Se realizó un examen periodontal completo y la toma de muestras en dos de los sitios más profundos de cada paciente. Las variables analizadas fueron: presencia de biofilm dental, sangrado al sondaje, profundidad al sondaje y nivel de inserción clínica. Los datos fueron analizados con la prueba de Kruskal Wallis con un nivel de significancia del 5%. Resultados: La periodontitis crónica estuvo en el 52,1% de los pacientes de 18 a 30 años, siendo más susceptibles los alcohólicos de riesgo y fumadores leves. El 91,04 % de alcohóli-cos y fumadores se encuentran asociados con la presencia de biofilm dental (p = 0,028) y en el diagnóstico molecular el 41,18% de los pacientes presentan más de 3 microorganismos (p = 0,039). Conclusión: Se evidenció la presencia de los periodontopatógenos estudiados en pacientes alcohólicos fumadores con periodontitis crónica.

Alcoholic and smoking patients have a greater predisposition to develop periodontal disease. Objective: To determine the presence of microorganisms periodontopathogens: Porphyromona gingivalis, Treponema denticola, Tannerella forsythia, Fusobacterium nucleatum and Aggregatibacter actinomycetemcomitans by Polymerase Chain Reaction (PCR), in alcoho-lic-smoking patients with chronic periodontitis. Materials and methods: The group was composed of 31 patients between the ages of 18 to 62-year-old, male alcoholics and/or smokers in which were excluded those who take some kind of drug, giving a sample of 23 patients with periodontal pockets ≥ 6mm from the Center of Rehabilitation of the city of Loja, Ecuador. A full periodontal examination and the sample taking were in two of the most profound sites of each patient. The variables analyzed were: the presence of dental biofilm, bleeding on probing, probing depth and clinical attachment level. The data were analyzed with the Kruskal Wallis Test with a significance level of 5%. Results: The chronic periodontitis was in the 52.1% of the patients between the ages of 18 to 30 years old, is more susceptible in risky alcoholics-smokers and low smokers. The 91.04 % of alcoholics and smokers are associated with the presence of dental biofilm (p = 0.028) and in the molecular diagnosis the 41.18% of patients exhibit more than 3 microorganisms (p = 0.039). Conclusion: That observed presence of the periodontopathogens in alcoholic-smoking patients with chronic periodontitis.

Os pacientes alcoólicos e fumantes apresentam uma possibilidade maior de desenvolver doença peridental. Objetivo: Determinar a presença do periodontopatógenos de microorganismos Porphyromona gingivalis, Treponema denticola, Fusobacterium nucleatum e Aggregatibacter actinomycetemcomitans por meio da Reação em Cadeia de Polimerasa (PCR),em pacientes alcoólicos e fumantes com periodontite crônico. Materiais e métodos: O universo pertenceu a 31 pacientes de 18 e 62 anos de idade de sexo masculino alcoólicos e/ou fumantes nos quais foram excluídos aqueles que consumiram algum tipo de droga, tendo uma amostra de 23 pacientes com bolsas peridentais. 6mm do Centro de Reabilitação da cidade de Loja, Equador. Um exame periodontal completo e a amostragem foram realizados em dois locais profundamente localizados de cada paciente. As variáveis analisadas eram: presença de biofilm dental, sangrou ao sondaje, profundidade ao sondaje e nível de suplemento clínico. Os dados foram analisados com o teste de Kruskal Wallis com um nível de significancia de 5%. Resultados: O periodontite crônico estava em 52,1% dos pacientes de 18 para 30 anos, enquanto sendo mais suscetível os alcoólicos de risco e fumantes ligeiros. 91,04% de alcoólicos e fumantes são associados com a presença de biofilm dental (p = 0028) e na diagnose 41,18% molecular dos pacientes apresenta mais de 3 microorganismos (p = 0039). Conclusões: A presença do periodontopatógenos foi comprovada nos pacientes alcoólicos e fumantes com periodontite crônico.

Determinação da resposta de imunoglobulina G sérica contra Omp29 de Aggregatibacter actinomycetemcomitans, em pacientes portadores de periodontite agressiva / Determination of serum immunoglobulin G response against Omp29 of Aggregatibacter actinomycetemcomitans in patients with aggressive periodontitis

A Periodontite Agressiva (PA), que atualmente pertence ao grupo das Periodontites estágios 3 e 4, distingue-se dos demais tipos de doença periodontal por seu início precoce, agregação familiar dos casos e por afetar pacientes sistemicamente saudáveis. Além disso, pode ser subclassificada em duas formas, localizada (PAL) e generalizada (PAG), em função de sua extensão. Muitas vezes, os depósitos de biofilme bacteriano são desproporcionais à quantidade de destruição óssea e perda de inserção que o paciente apresenta, independente da subclassificação. O microrganismo mais relacionado à etiopatogênese da doença é o Aggregatibacter actinomycetemcomitans (A. actinomycetemcomitans), incluindo os seus principais sorotipos a, b e c, amplamente estudados. Associado a estas condições, A. actinomycetemcomitans apresenta alguns fatores de virulência como uma leucotoxina, principalmente ligada ao sorotipo b - clone JP2 (que é altamente leucotóxico) e proteínas de membrana externa (OMPs), especialmente Omp29. A resposta de imunoglobulina G (IgG) sérica contra este patógeno foi anteriormente associada à ambas as formas de PA, porém, são escassos os estudos que avaliaram longitudinalmente a resposta sérica frente a variáveis como estas. Dessa maneira, o objetivo desse estudo foi avaliar a resposta sérica, de 27 pacientes com PA e 10 pacientes periodontalmente saudáveis, contra Omp29 e sorotipos de A. actinomycetemcomitans, através de um ensaio ELISA, correlacionando com o número de cópias de JP2 (obtidos por qPCR em tempo real) e parâmetros clínicos, a partir de dados anteriormente coletados por nosso grupo. Todos os dados foram obtidos antes do início do tratamento e um ano após seu término. O tratamento consistiu de orientações de higiene bucal, tratamento mecânico e antibioticoterapia. Os dados resultantes do estudo mostraram que em ambas as formas de PA houve uma redução significativa na profundidade clínica de sondagem (PCS)(p<0,001), nível clínico de inserção (NCI)(p<0,001) e na resposta sérica contra Omp29 e sorotipo c de A. actinomycetemcomitans(p>0,005). Após 1 ano, os valores de densidade óptica (D.O.) normalizados para Omp29 e sorotipos de A. actinomycetemcomitans, bem como o número de cópias do clone JP2 tornaram-se similares aos níveis encontrados nos controles. A redução no número de cópias do clone JP2 foi correlacionada com redução da PCS em PAL(r=0.80,p=0.0042) e valores de D.O. normalizados de Omp29 em PAG(r=0.66,p=0.005). O estudo concluiu que o tratamento periodontal foi eficaz em alterar a resposta sérica contra Omp29 e sorotipos de A. actinomycetemcomitans, além de reduzir o número de cópias do clone JP2 e melhorar os parâmetros clínicos.

Real-time PCR quantification of 9 periodontal pathogens in saliva samples from periodontally healthy Korean young adults

PURPOSE: Few studies have examined periodontal pathogens from saliva samples in periodontally healthy young adults. The purposes of this study were to determine the prevalence of periodontopathic bacteria and to quantify periodontal pathogens in saliva samples using real-time polymerase chain reaction (PCR) assays in periodontally healthy Korean young adults under 35 years of age. METHODS: Nine major periodontal pathogens were analyzed by real-time PCR in saliva from 94 periodontally healthy young adults. Quantification of Aggregatibacter actinomycetemcomitans, Porphyromonas gingivalis, Tannerella forsythia, Treponema denticola, Prevotella intermedia, Fusobacterium nucleatum, Campylobacter rectus, Peptostreptococcus anaerobius, and Eikenella corrodens was performed by DNA copy number measurement. RESULTS: F. nucleatum and E. corrodens were detected in all subjects; the numbers of positive samples were 87 (92.6%), 91 (96.8%), and 90 (95.7%) for P. gingivalis, P. anaerobius, and C. rectus, respectively. Other pathogens were also detected in periodontally healthy subjects. Analysis of DNA copy numbers revealed that the most abundant periodontal pathogen was F. nucleatum, which was significantly more prevalent than all other bacteria (P < 0.001), followed by P. anaerobius, P. gingivalis, E. corrodens, C. rectus, and T. denticola. There was no significant difference in the prevalence of each bacterium between men and women. The DNA copy number of total bacteria was significantly higher in men than in women. CONCLUSIONS: Major periodontal pathogens were prevalent in the saliva of periodontally healthy Korean young adults. Therefore, we suggest that the development of periodontal disease should not be overlooked in periodontally healthy young people, as it can arise due to periodontal pathogen imbalance and host susceptibility.

Effect of Various Agents on Oral Bacterial Phagocytosis in THP-1 Cells

Phagocytosis is a fundamental process in which phagocytes capture and ingest foreign particles including pathogenic bacteria. Several oral pathogens have anti-phagocytic strategies, which allow them to escape from and survive in phagocytes. Impaired bacteria phagocytosis increases inflammation and contributes to inflammatory diseases. The purpose of this study is to investigate the influences of various agents on oral pathogenic phagocytosis. To determine phagocytosis, Streptococcus mutans, Fusobacterium nucleatum, Aggregatibacter actinomycetemcomitans and Porphyromonas gingivalis were stained with 5-(and-6)-carboxyfluorescein diacetate succinimidyl ester (CFSE), and was measured using flowcytometery and confocal microscopy. The influencing factors on phagocytosis were evaluated through the pretreatment of ROS inhibitor (N-acetyl-L-cysteine (NAC)), lysozyme, potassium chloride (KCI) and adenosine triphosphate (ATP) in THP-1 cells. Expression of pro-inflammatory cytokines was determined by enzyme-linked immunosorbent assay (ELISA). The phagocytosis of various bacteria increased in a MOI-dependent manner. Among the tested bacteria, phagocytosis of P. gingivalis showed the highest fluorescent intensity at same infection time. Among the tested inhibitors, the NAC treatment significantly inhibited phagocytosis in all tested bacteria. In addition, NAC treatment indicated a similar pattern under the confocal microscopy. Moreover, NAC treatment significantly increased the bacteria-induced secretion of IL-1β among the tested inhibitors. Taken together, we conclude that the phagocytosis occurs differently depending on each bacterium. Down-regulation by ROS production inhibited phagocytosis and lead increased of oral pathogens-associated inflammation.

Microbiological and clinical effects of probiotics and antibiotics on nonsurgical treatment of chronic periodontitis: a randomized placebo- controlled trial with 9-month follow-up

ABSTRACT Objective: The aim of this double-blind, placebo-controlled and parallel- arm randomized clinical trial was to evaluate the effects of Lactobacillus rhamnosus SP1-containing probiotic sachet and azithromycin tablets as an adjunct to nonsurgical therapy in clinical parameters and in presence and levels of Tannerella forsythia, Porphyromonas gingivalis and Aggregatibacter actinomycetemcomitans. Material and Methods: Forty-seven systemically healthy volunteers with chronic periodontitis were recruited and monitored clinically and microbiologically at baseline for 3, 6 and 9 months after therapy. Subgingival plaque samples were collected from four periodontal sites with clinical attachment level ≥1 mm, probing pocket depth ≥4 mm and bleeding on probing, one site in each quadrant. Samples were cultivated and processed using the PCR technique. Patients received nonsurgical therapy including scaling and root planing (SRP) and were randomly assigned to a probiotic (n=16), antibiotic (n = 16) or placebo (n = 15) group. L. rhamnosus SP1 was taken once a day for 3 months. Azithromycin 500mg was taken once a day for 5 days. Results: All groups showed improvements in clinical and microbiological parameters at all time points evaluated. Probiotic and antibiotic groups showed greater reductions in cultivable microbiota compared with baseline. The placebo group showed greater reduction in number of subjects with P. gingivalis compared with baseline. However, there were no significant differences between groups. Conclusions: The adjunctive use of L. rhamnosus SP1 sachets and azithromycin during initial therapy resulted in similar clinical and microbiological improvements compared with the placebo group.

Incorporation of silver nanoparticles on the surface of orthodontic microimplants to achieve antimicrobial properties / 대한치과교정학회지

OBJECTIVE: Microbial aggregation around dental implants can lead to loss/loosening of the implants. This study was aimed at surface treating titanium microimplants with silver nanoparticles (AgNPs) to achieve antibacterial properties. METHODS: AgNP-modified titanium microimplants (Ti-nAg) were prepared using two methods. The first method involved coating the microimplants with regular AgNPs (Ti-AgNP) and the second involved coating them with a AgNP-coated biopolymer (Ti-BP-AgNP). The topologies, microstructures, and chemical compositions of the surfaces of the Ti-nAg were characterized by scanning electron microscopy (SEM) equipped with energy-dispersive spectrometer (EDS) and X-ray photoelectron spectroscopy (XPS). Disk diffusion tests using Streptococcus mutans, Streptococcus sanguinis, and Aggregatibacter actinomycetemcomitans were performed to test the antibacterial activity of the Ti-nAg microimplants. RESULTS: SEM revealed that only a meager amount of AgNPs was sparsely deposited on the Ti-AgNP surface with the first method, while a layer of AgNP-coated biopolymer extended along the Ti-BP-AgNP surface in the second method. The diameters of the coated nanoparticles were in the range of 10 to 30 nm. EDS revealed 1.05 atomic % of Ag on the surface of the Ti-AgNP and an astounding 21.2 atomic % on the surface of the Ti-BP-AgNP. XPS confirmed the metallic state of silver on the Ti-BP-AgNP surface. After 24 hours of incubation, clear zones of inhibition were seen around the Ti-BP-AgNP microimplants in all three test bacterial culture plates, whereas no antibacterial effect was observed with the Ti-AgNP microimplants. CONCLUSIONS: Titanium microimplants modified with Ti-BP-AgNP exhibit excellent antibacterial properties, making them a promising implantable biomaterial.

Ursodeoxycholic Acid Inhibits Inflammatory Cytokine Expression in THP-1 Cells Infected with Aggregatibacter actinomycetemcomitans

BACKGROUND: Periodontitis is an inflammatory disease characterized by the breakdown of tooth-supporting tissues, leading to tooth loss. Aggregatibacter actinomycetemcomitans are major etiologic bacterium causing aggressive periodontitis. Ursodeoxycholic acid (UDCA), a hydrophilic gall bladder acid, has been used as an effective drug for various diseases related to immunity. The aim of this study was to investigate the effect of UDCA on the inflammatory response induced by A. actinomycetemcomitans. METHODS: A human acute monocytic leukemia cell line (THP-1) was differentiated to macrophage- like cells by treatment with phorbol 12-mystristate 13-acetate (PMA) and used for all experiments. The cytotoxic effect of UDCA was examined by MTT assay. THP-1 cells were pretreated with UDCA for 30 min before A. actinomycetemcomitans infection and the culture supernatant was analyzed for various cytokine production by ELISA. The effect of UDCA on bacterial growth was examined by measuring optical densities using a spectrophotometer. RESULTS: UDCA showed no cytotoxic effect on THP-1 cells, up to 80 µM Ed highlight: Please confirm technical meaning. UDCA pretreatment inhibited the A. actinomycetemcomitans-induced IL-1β, TNF-α, and IL-17A secretion in a dosedependent manner. UDCA also inhibited IL-21 production at 60 µM. The production of IL-12 and IL-4 was not influenced by A. actinomycetemcomitans infection. CONCLUSION: These findings indicate that UDCA inhibits the production of inflammatory cytokines involved in innate and Th17 immune responses in A. actinomycetemcomitans-infected THP-1-derived macrophages, which suggests its possible use for the control of aggressive periodontitis.

Transmissão intrafamiliar de patógenos periodontais / Intrafamilial transmission of periodontal pathogens: a literature review

Objetivo: revisar quais seriam os diferentes fatores envolvidos na transmissão de periodontopatógenos entre membros de uma mesma família e quais as suas consequências. Material e métodos: uma revisão da literatura foi realizada na base de dados PubMed, utilizando os termos "vertical transmission", "periodontal pathogens", "oral colonization", e "periodontitis". Resultados: após a leitura do título e resumo, 30 artigos foram incluídos nesta revisão. A transmissão de patógenos periodontais entre indivíduos de uma mesma família está relacionada à passagem via salivar e ao compartilhamento alimentar e de higiene, aos cuidados dos filhos pelos pais ou cuidadores, e ao contato íntimo entre cônjuges. Estudos que avaliaram a transmissão do Aggregatibacter actinomycetemcomitans entre indivíduos de uma mesma família mostraram a ocorrência da transmissão vertical, embora também ocorra transmissão horizontal. Entretanto, resultados semelhantes não puderam ser observados para o Porphyromonas gingivalis. Enquanto alguns relatos indicam a ocorrência de transmissão horizontal desta bactéria, diversos outros estudos indicam características bacterianas que reduzem sua ocorrência. Conclusão: a colonização oral por microrganismos patogênicos está relacionada à transmissão vertical e horizontal de patógenos, embora a persistência dos microrganismos pareça estar relacionada a fatores individuais do hospedeiro e características dos patógenos. Além disso, atividades preventivas e terapêuticas devem ser realizadas de forma a alterar o processo de transmissão, colonização e o maior risco do desenvolvimento de problemas periodontais.

Objective: to review the different factors involved in the transmission of periodontopathogens between members of the same family and their consequences. Material and methods: an electronic literature review was conducted at the PubMed using the keywords "vertical transmission", "periodontal pathogens", "oral colonization", and "periodontitis". Results: after reading of title and abstract, 30 articles were included. The transmission of periodontal pathogens among individuals of the same family is related to the passage through salivary and food and hygiene sharing, the care of the children by parents or caregivers, and the intimate contact between individuals. Studies evaluating the transmission of Aggregatibacter actinomycetemcomitans among individuals from the same family showed the occurrence of vertical transmission and horizontal transmission. However, similar results could not be observed for Porphyromonas gingivalis. While some reports indicate the occurrence of horizontal transmission, several other studies indicate bacterial characteristics that reduce its occurrence. Conclusion: oral colonization by pathogenic microorganisms is related to its vertical and horizontal transmission, although the persistence of the microorganisms seems to be related to individual host factors and pathogen characteristics. In addition, preventive and therapeutic activities must be performed in a way that will alter the transmission, colonization and the greater risk of developing periodontal problems.

Influence of Aae Autotransporter Protein on Adhesion and Biofilm Formation by Aggregatibacter actinomycetemcomitans

Abstract The periodontopathogen Aggregatibacter actinomycetemcomitans colonizes oral cavity by binding to and invading epithelial cells as well as by participating in biofilms formed on hard surfaces. Aae, an autotransporter protein, is implicated in bacterial adhesion to epithelial cells. Due to the multiple functions of bacterial autotransporter proteins, this study aimed to evaluate the role of aae in A. actinomycetemcomitans ability to adhere to both saliva-coated hydroxyapatite (SHA) and biofilm. An aae null mutant was constructed. Its hydrophobic properties as well as its ability to adhere to epithelial cells, SHA and to form biofilm were evaluated and compared with the parental strain, A. actinomycetemcomitans VT1169. The aae null mutant showed reduced hydrophobicity, as well as decreased binding to SHA and biofilm formation compared to the parental strain. These data suggest that aae mediates A. actinomycetemcomitans adhesion to epithelial cells and may be involved in biofilm formation and interaction with adsorbed salivary proteins.

Resumo O peridontopatógeno Aggregatibacter actinomycetemcomitans coloniza a cavidade oral aderindo e invadindo as células epiteliais e participando da formação de biofilme em superfícies duras. Aae, uma proteína autotransportadora está relacionada com a adesão bacteriana às células epiteliais. Devido às múltiplas funções desempenhadas por proteínas bacterianas autotransportadoras, este estudo teve como objetivo avaliar o papel de aae de A. actinomycetemcomitans tanto na capacidade de aderir à hidroxiapatita recoberta por saliva (SHA), quanto a de formar biofilme. Um mutante nulo aae foi construído. Suas propriedades hidrofóbicas, bem como a sia capacidade para aderir às células epiteliais, à SHA e para formar biofilme foram avaliadas e comparadas com a cepa -mãe, A. Actinomycetemcomitans VT1169. O mutante nulo aae apresentou redução de hidrofobicidade, assim como diminuição da adesão à SHA e na formação de biofilme, quando comparado à cepa parental. Estes dados sugerem que aae media a adesão de A. Actinomycetemcomitans às células epiteliais e pode também estar envolvida na formação de biofilme e na interação com proteínas salivares adsorvidas.