Impact of combined at-home bleaching and whitening toothpaste use on the surface and color of a composite resin.

Objective: This in vitro study aimed to evaluate the effects of different whitening toothpastes on a composite resin during at-home bleaching with 10% carbamide peroxide. Materials and Methods: Sixty samples (7 mm × 2 mm) were used for color and roughness analyses, while another 60 samples (3 mm × 2 mm) were utilized to assess microhardness. The factors analyzed included toothpaste, for which 5 options with varying active agents were tested (distilled water; conventional toothpaste; whitening toothpaste with abrasive agents; whitening toothpaste with abrasive and chemical agents; and whitening toothpaste with abrasive, chemical, and bleaching agents). Brushing and application of whitening gel were performed for 14 days. Surface microhardness (SMH), surface roughness (Ra), and color (∆L*, ∆a*, ∆b, ∆E*ab, and ∆E00) were analyzed. The Ra and SMH data were analyzed using mixed generalized linear models for repeated measures, while the color results were assessed using the Kruskal-Wallis and Dunn tests. Results: Between the initial and final time points, all groups demonstrated significant increases in Ra and reductions in SMH. No significant differences were found between groups for SMH at the final time point, at which all groups differed from the distilled water group. Conventional toothpaste exhibited the lowest Ra, while whitening toothpaste with abrasive agent had the highest value. No significant differences were observed in ∆L*, ∆a*, and ∆b. Conclusions: While toothpaste composition did not affect the color stability and microhardness of resin composite, combining toothbrushing with whitening toothpaste and at-home bleaching enhanced the change in Ra.

Evaluation of the efficacy of the use of violet LED light in the bleaching of damaged primary incisors darkened by trauma.

BACKGROUND: The aim of this study was to evaluate efficacy of violet LED light for the bleaching treatment of primary incisors darkened by trauma. METHODS: Twenty deciduous incisors with color change were selected, divided into two groups: control - no bleaching protocol was applied, and VL- treated with violet LED. The change color analysis was taken in each tooth, by spectrophotometer. In three different time: baseline - before treatment, after 4 treatment sessions and after 8 treatment sessions. RESULTS: The color change data were analyzed using ANOVA and a post- hoc Tukey tests (α=0.05). After 4 and 8 sessions no differences were observed between the groups (p<0.05). CONCLUSIONS: Thus, it can be concluded that violet LED light was not effective in bleaching primary incisors darkened by trauma after 8 sessions.

Salivary Microbial Dysbiosis Is Associated With Peri-Implantitis: A Case-Control Study in a Brazilian Population.

Background and Objectives: The aim of this study was to examine the salivary microbiome in healthy peri-implant sites and those with peri-implantitis. Methods: Saliva samples were collected from 21 participants with healthy peri-implant sites and 21 participants with peri-implantitis. The V4 hypervariable region of the 16S rRNA gene was sequenced using the Ion Torrent PGM System (Ion 318™ Chip v2 400). The NGS analysis and composition of the salivary microbiome were determined by taxonomy assignment. Downstream bioinformatic analyses were performed in QIIME (v 1.9.1). Results: Clinical differences according to peri-implant condition status were found. Alpha diversity metrics revealed that the bacterial communities of participants with healthy peri-implant sites tended to have a richer microbial composition than individuals with peri-implantitis. In terms of beta diversity, bleeding on probing (BoP) may influence the microbial diversity. However, no clear partitioning was noted between the salivary microbiome of volunteers with healthy peri-implant sites or volunteers with peri-implantitis. The highest relative abundance of Stenotrophomonas, Enterococcus and Leuconostoc genus, and Faecalibacterium prausnitzii, Haemophilus parainfluenzae, Prevotella copri, Bacteroides vulgatus, and Bacteroides stercoris bacterial species was found in participants with peri-implantitis when compared with those with healthy peri-implant sites. Conclusion: Differences in salivary microbiome composition were observed between patients with healthy peri-implant sites and those with peri-implantitis. BoP could affect the diversity (beta diversity) of the salivary microbiome.

Color stability of dental enamel bleached with violet LED associated with or without Low concentration peroxide gels.

BACKGROUND: This study aimed to evaluate the in vitro color of dental enamel bleached with the violet LED, associated with or without low-concentration of peroxide; analyzed in two time intervals: 24 h later and 6 months after the treatment. METHODS: Ninety fragments of bovine teeth (6 × 6 mm and 3 mm thick) were randomly divided into 6 groups according to bleaching treatment: NB - no bleaching, VL - Violet LED, HP- 7.5 % hydrogen peroxide, HP + VL - 7.5 % hydrogen peroxide + violet LED, CP - 22 % carbamide peroxide, CP + VL - 22 % carbamide peroxide + violet LED. The color change was analyzed by using a spectrophotometer, at time intervals of 24 h and 6 months after performing the bleaching techniques (n = 12). Scanning electron microscopy (SEM) was performed to verify the enamel surface morphology after treatment (n = 3). RESULTS: The color change data were analyzed using ANOVA and a post-hoc Tukey tests (α = 0.05). The VL group showed chromatic changes after 24 h of treatment, however the groups submitted to bleaching gel treatments associated with or without violet LED (CP + VL, CP, HP, HP + VL) showed the highest color change values at all time intervals analyzed, with color stability after 6 months of treatment for the CP + VL group. Scanning electron microscopy analysis showed the greatest change in enamel surface for Groups CP and HP. CONCLUSIONS: It could be concluded that violet LED had immediate bleaching effect without promoting significant changes in enamel morphology, however the association with carbamide peroxide 22 % showed color stability and greater bleaching efficacy than the use of violet LED alone, after 6 months.

Oral prevalence and antifungal susceptibility of Candida species in cystic fibrosis patients.

OBJECTIVE: This study aimed at assessing the oral prevalence ofCandida species in cystic fibrosis patients and the antifungal susceptibility of the isolates. DESIGN: One hundred patients aged 3-20 years old were included in the study and were divided into three groups: G1 (low severity disease): 25 cystic fibrosis patients with Shwachman-Kulczycki score (SK) between 100 and 71; G2 (high severity disease): 25 cystic fibrosis patients with SK score under 40; and G3 (control): 50 healthy patients age- and gender-matched to cystic fibrosis patients. Stimulated saliva samples were collected and the oral fungal concentrations were assessed. Isolates were identified by phenotypic and genotypic tests. Antifungal susceptibilities to amphotericin B, flucytosine and fluconazole were determined by CLSI methodology. Fungal counts were compared by Kruskal Wallis and Dunn's test (5%). RESULTS: A total of 68 % of Group 1, 80 % of Group 2, and 44 % of controls yielded positive Candida cultures. Oral concentrations of fungi were significantly higher in cystic fibrosis patients in relation to the control group (p < 0.0005). No significant difference was observed between low and high severity cystic fibrosis groups (p > 0.05). C. albicans was most frequently isolated species in all groups. Higher variability of Candida species was observed in the control group. C. dubliniensis and C. tropicalis were only detected among cystic fibrosis groups. All the isolates were susceptible to flucytosine and fluconazole. CONCLUSIONS: Patients with cystic fibrosis were more frequently colonized by Candida species and showed higher oral fungal burden. No antifungal resistant isolates were detected.

Evaluation of the masticatory biomechanical function in Down syndrome and its Influence on sleep disorders, body adiposity and salivary parameters.

OBJECTIVE: To evaluate the phenotypic features of the masticatory biomechanics in atypical subjects with Down syndrome (DS). Its influence was analysed on sleep disorders, body adiposity and its risks, and some physicochemical properties of saliva. METHODS: Seventy subjects were enrolled to assess masticatory biomechanical function and divided into two groups: DS and control groups. Electrical activities of the masseter and temporal muscles (at rest and in maximum voluntary clench-MVC), maximum bite force-MBF and maximum mouth opening-MMO were investigated. Among the atypical subjects, just 24 participants underwent the anthropometry, the polysomnography II and the saliva testing (salivary flow rate-SFR, buffer capacity-BC and salivary cortisol levels, morning/SC-AM and night/SC-PM). RESULTS: MVC and MBF values showed high statistical significance in the control group (P < .001) than in the DS group of 35. MMO values were slightly increased in the DS group in relation to the control group. Overweight and obesity were found in both genders. Atypical women showed higher risk to develop cardiovascular-metabolic diseases than in atypical men. OSA severe was 20% for atypical women and 42.8% for atypical men, whereas snoring index was present in all genders. SFR was reduced in 100% of atypical subjects (hyposalivation in 10% women and 28.5% men). Furthermore, 100% BC, 66.6% SC-AM and 91.6% SC-PM showed normal patterns. CONCLUSION: Masseter and temporal muscle hypotonia was found in all atypical subjects with DS. This muscle dysfunction strongly was related to overweight/obesity, risks for development of cardiovascular/metabolic diseases, OSA severity, successive snoring episodes and salivary flow reduction in DS.

Effect of violet led associated with low-concentration hydrogen peroxide on enamel surface roughness

Aim: The present study aimed to assess in vitro the effect ofviolet LED in tooth bleaching techniques associated or not withlow-concentration hydrogen peroxide gel on enamel surfaceroughness. Methods: Fifty-two enamel fragments of bovineteeth were flattened and polished (4x4x3 mm) and dividedinto four groups according to bleaching treatment: VL- VioletLED; HP- 7.5% hydrogen peroxide; HP+VL- 7.5% hydrogenperoxide + violet LED; C- No bleaching (control). Before thetreatments, all specimens were immersed in 20 mL of blacktea for six days, changing solutions every 24 h to simulatethe staining of specimens. Forty fragments were used toanalyze surface roughness (n=10) and 12 fragments wereused for the morphological analysis (SEM) (n=3). Results:The data were submitted to one-way ANOVA and a post-hocTukey test. The lower roughness values was observed for thegroup that did not receive bleaching treatment (C), differingsignificantly only from the group bleached with 7.5% hydrogenperoxide + violet LED (HP+VL) (p=0.0077). The remaininggroups did not show significant differences in roughnessvalues (p>0.05). The scanning electron microscopy analysisshowed irregularities on the enamel surface regardless ofthe treatment received. Conclusion: The results showedthat bleaching treatments with violet LED associated withlow-concentration hydrogen peroxide gels (7.5%) increasethe surface roughness of tooth enamel

Eficácia polissonográfica de um aparelho intraoral semiflexível em pacientes apneicos resistentes ao CPAP ­ estudo preliminar / Polysomnographic efficacy of a semi-flexible intraoral appliance in CPAPresistant apneic patients ­ preliminary study

INTRODUÇÃO: Os aparelhos intraorais (AIO) possuem indicação para tratamento da Síndrome da Apneia Obstrutiva do Sono (SAOS) inclusive em pacientes com baixa adesão ao CPAP. A polissonografia com o AIO pode confirmar benefício terapêutico. MÉTODOS: Compararam-se os resultados polissonográficos de um AIO semiflexível em pacientes sob uso inadequado do CPAP por meio de estudo-piloto retrospectivo, incluindo 17 pacientes (11 homens e 6 mulheres) com 53,7 +- 7,8 anos, IMC de 27,5 +- 4,1kg/m2 e índice de apneia- -hipopneia basal (IAH) de 35,0 +- 19,8/h. Confirmados o uso inadequado ou recusa do CPAP, os pacientes receberam um aparelho com propulsão semiflexível (A-QUALITY) e, após titulação completa, novas polissonografias foram comparadas aos registros basais e com CPAP. Utilizou-se ANOVA para medidas repetidas e post-hoc Bonferroni (p < 0,05). RESULTADOS: Houve redução semelhante no IAH com AIO (7,7 +- 1,7/h) e CPAP (6,1 +- 1,6/h), ambos comparados ao basal (p < 0,001). O índice de dessaturação de O2 foi reduzido com AIO (2,4 +- 0,6/h) e CPAP (1,3 +- 0,6/h), ambos comparados ao basal (15,7 +- 3,8), (p <0,001). O índice de despertares também foi minimizado com AIO (7,2 +- 1,9/h) e CPAP (4,2 +- 0,7/h), ambos comparados ao basal (18,9 +- 5,3), (p<0,001). A eficiência do sono foi maior com o AIO comparado ao CPAP (87,2 +- 2,1 x 75,6 +- 3,9) (p<0,05). CONCLUSÃO: O tratamento com o aparelho selecionado resultou em melhora nos registros polissonográficos nessa amostra e pode ser indicado como alternativa ao CPAP em pacientes subtratados (AU)

INTRODUCTION: Intraoral appliances (IOA) are indicated for treatment of Obstructive Sleep Apnea Syndrome (OSAS) even in patients with poor adherence to CPAP. Polysomnography with IOA may confirm therapeutic benefit. METHODS: Polysomnographic results of a semiflexible IOA in patients under inadequate use of CPAP were compared by a retrospective pilot study including 17 patients (11 men and 6 women) aged 53.7 +- 7.8 years, BMI of 27.05 +- 4.1kg/m2 and basal apnea-hypopnea index (AHI) of 35.0 +- 19.8/h. Confirmed the inappropriate use or refusal of CPAP, the patients received a semiflexible propulsion device (AQUALITY) and, after complete titration, new polysomnographies were compared to baseline and CPAP registers. ANOVA was used for repeated and post-hoc Bonferroni measurements (p <0.05). RESULTS: There was a similar reduction in AHI with OA (7.7 +- 1.7/h) and CPAP (6.1 +- 1.6/h), both compared to baseline (p <0.001). The O2 desaturation index was reduced with IOA (2.4 +- 0.6 h) and CPAP (1.3 +- 0.6/h), both compared to baseline (15.7 +- 3.8) (p <0.001). Awakening rates were also minimized with IOA (7.2 +- 1.9/h) and CPAP (4.2 +- 0.7/h), both compared to baseline (18.9 +- 5.3) (p <0.001). Sleep efficiency was higher with IOA compared to CPAP (87,2 +- 2,1 x 75,6 +- 3,9) (p <0.05). CONCLUSION: Treatment with the selected device resulted in improved polysomnographic records in this sample and may be indicated as an alternative to CPAP in undertreated patients. (AU)

Reduced salivary flow rate and high levels of oxidative stress in whole saliva of children with Down syndrome.

AIM: To investigate salivary parameters between children with Down Syndrome (DS) and without DS. MATERIALS AND METHODS: Stimulated whole saliva was collected from 18 children with DS and 23 without DS. Salivary flow rate, pH, and salivary buffering capacity were determined. Cariogenic microorganisms were quantified by culture, and periodontopathogens by quantitative real-time polymerase chain reaction. The antioxidant profile was quantified spectrophotometrically, while malondialdehyde (MDA) was quantified by high-performance liquid chromatography. Data were analyzed by Mann-Whitney test and Spearman correlation (α = 0.05). RESULTS: Salivary flow rate was significantly lower in DS than in controls (p < 0.0001). Significant higher difference was observed for total protein dosage (p < 0.0001), superoxide dismutase activity (SOD) (p = 0.0002), and MDA (p < 0.001) in DS group. CONCLUSIONS: Reduced salivary flow rate might be an important factor in oral diseases development. High salivary levels of SOD and MDA show the significant influence of the oxidative stress and the early-onset periodontal disease in DS people.

Gallic acid/hydroxypropyl-ß-cyclodextrin complex: Improving solubility for application on in vitro/ in vivo Candida albicans biofilms.

The aim of this study was to increase the solubility of gallic acid (GA) for the treatment of Candida albicans biofilm, which is very difficult to treat and requires high drug concentrations. Cyclodextrins (CDs) were used for this purpose. Complexes were evaluated by phase-solubility studies, prepared by spray drying and characterized by drug loading, scanning electron microscopy (SEM) and differential scanning calorimetry (DSC). The complexes were tested on C. albicans biofilm using in vitro and in vivo models. HPßCD formed soluble inclusion complexes with GA. The percentage of GA in GA/HPßCD was 10.8 ± 0.01%. The SEM and DSC analyses confirmed the formation of inclusion complexes. GA/HPßCD maintained the antimicrobial activity of the pure GA. GA/HPßCD was effective on C. albicans biofilms of 24 and 48h. The in vivo results showed an anti-inflammatory activity of GA/HPßCD with no difference in invading hypha counting among the groups. This study encourages the development of new antifungal agents.

Análise microbiológica e imunologica do fluido gengival e proteoma salivar de individuos com Sindrome de Down com doença periodontal / Microbiological and immunological analysis in the gingival crevicular fluid and salivary proteome analysis in individuals with Down syndrome with periodontal disease

O objetivo deste estudo foi avaliar a quantidade de periodontopatógenos e de citocinas inflamatórias no fluido gengival, bem como as proteínas salivares em indivíduos com Síndrome de Down (SD) com Doença Periodontal (DP), comparando-os com indivíduos cromossomicamente normais, antes e 45 dias após o tratamento periodontal não-cirúrgico. Para detectar e quantificar as bactérias (Porphyromonas gingivalis, Tannerella forsythia e Treponema denticola), o fluido gengival foi coletado de 35 indivíduos com DP, sendo 23 indivíduos com SD e 12 não-sindrômicos (controle). Para quantificar as citocinas inflamatórias e as proteínas salivares foram coletados fluido gengival e saliva de 30 indivíduos com DP, sendo 20 indivíduos com SD e 10 não-sindrômicos (controle). Os efeitos do tratamento nos parâmetros clínicos foram positivos para o índice de placa, sangramento à sondagem, profundidade de sondagem e nível de inserção, em ambos os grupos. Porém, a contagem dos periodontopatógenos foi maior nos indivíduos com SD comparados com o grupo controle, antes e 45 dias após o tratamento periodontal. As citocinas Th1, Th2 e Th17 também foram encontradas em maiores quantidades nos indivíduos com SD do que nos controle, mesmo depois do tratamento periodontal. Adicionalmente, maiores quantidades de proteínas salivares com propriedades antimicrobianas, lubrificação, metabolismo, organização celular, resposta imune e transporte foram encontradas em indivíduos com SD depois do tratamento periodontal. Conclui-se que os resultados desta pesquisa podem contribuir para uma compreensão mais aprofundada do comportamento microbiológico, imunológico e do proteoma salivar de indivíduos com SD, e, consequentemente, explicar a alta prevalência e severidade da doença periodontal nesses indivíduos.

The aim of this study was to quantify the periodontopathogens, inflammatory cytokines and salivary proteins in subjects with Down syndrome (DS) and normal subjects, both with periodontal disease (PD), before and 45 days after non-surgical periodontal therapy. To detect and quantify bacteria (Porphyromonas gingivalis, Tannerella forsythia, and Treponema denticola), crevicular gingival fluid (CGF) was collected from 35 individuals with PD, 23 with DS and 12 non-syndromic (control). To quantify the inflammatory cytokines and salivary proteins, CGF and saliva of 30 individuals with PD, 20 with SD and 10 non-syndromic (control) were collected. The effects of the non-surgical periodontal therapy on clinical parameters were positive in both groups. However, the count of periodontopathogens was higher in individuals with DS compared with the control group, before and after periodontal therapy.Th1, Th2 and Th17 cytokines were also found in higher amounts in individuals with DS even after periodontal therapy compared with control patients. Furthermore, higher amounts of salivary proteins with antimicrobial properties, lubrication, metabolism, cellular organization, immune response and transport were quantified in individuals with DS after periodontal therapy. Despite of clinical parameters improvement after non-surgical periodontal therapy in subjects with DS, it is concluded that the results of this study may contribute to a more profound understanding of microbiological and immunological behavior, as well as knowledge of the salivary proteome in individuals with Down syndrome, and also might explain the high prevalence and severity of periodontal disease in these individuals

Inorganic elemental analysis and identification of residual monomers released from different glass ionomer cements in cell culture medium / Análise elementar inorgânica e identificação de monômeros residuais orgânicos liberados por diferentes cimentos de ionômero de vidro

Introduction: Glass ionomer cements (GICs) release inorganic elements and organic residual monomers with the potential for deleterious effects on pulp cells. Objective: To identify and quantify inorganic elements present in different GICs and released components from these materials in cell culture medium. Material and Method: Samples of two resin-modified GICs for base/liner (Vitrebond and Fuji Lining LC), two resin-modified restorative GICs (Vitremer and Fuji II LC) and two conventional restorative GICs (Ketac Fil Plus and Ketac Molar Easymix) were prepared and analyzed by Energy-Dispersive X-Ray Fluorescence Spectrometry (EDXRF). Extracts of these materials were obtained by immersion of each sample in separate containers of DMEM for 24 h (total surface-liquid ratio = 45.7 mm²/mL). The extracts were analyzed by EDXRF and Gas Chromatography-Mass Spectrometry (GC-MS). Result: Higher percentages of strontium, silicon and aluminum were identified in Vitrebond, Vitremer, Fuji Lining LC, Fuji II LC, and Ketac Fil Plus, while zinc was detected only in Vitrebond. Ketac Molar Easymix presented a greater atomic composition of lanthanum, calcium, aluminum and silicon. Strontium was detected in the extracts from all materials except Ketac Molar Easymix; calcium was present in extracts from Ketac Fil Plus; zinc only in Vitrebond; and silicon in Fuji II LC extract. The analysis by GC-MS detected 2-hydroxyethyl-methacrylate (HEMA) in the extracts from all resin-modified GICs, and iodine benzene was detected only in the Vitrebond extract. Conclusion: Of the GICs sampled, Vitrebond released the highest number of components with cytotoxic potential.

Introdução: Os cimentos de ionômero de vidro (CIVs) liberam elementos inorgânicos e monômeros orgânicos residuais que têm o potencial de causar efeitos deletérios sobre as células pulpares. Objetivo: Identificar e quantificar os elementos inorgânicos presentes em diferentes CIVs, bem como os componentes liberados por estes materiais em meio de cultura celular. Material e Método: Espécimes cilindricos de dois CIVs modificados por resina para base/forramento (Vitrebond e Fuji Lining LC), dois CIVs modificados por resina restauradores (Vitremer e Fuji II LC) e dois CIVs convencionais restauradores (Ketac Fil Plus e Ketac Molar Easymix) foram preparados e analisados por Espectrometria de Fluorescência de Raios X por Energia Dispersiva (EDXRF). Em seguida, extratos de 24h desses materiais foram obtidos e analisados por EDXRF e por Cromatografia Gasosa/Espectrometria de Massa (CG/EM). Resultado: Os elementos inorgânicos identificados em maior porcentagem nos CIVs Vitrebond, Fuji Lining LC, Vitremer, Fuji II LC e Ketac Fil Plus foram estrôncio, silício e alumínio, enquanto o zinco foi detectado apenas no Vitrebond. O Ketac Molar Easymix apresentou maior porcentagem dos elementos lantânio, cálcio, alumínio e silício. Estrôncio foi detectado nos extratos de todos os materiais, exceto no Ketac Molar Easymix; cálcio estava presente no extrato do Ketac Fil Plus; zinco apenas no Vitrebond; e silício no extrato do Fuji II LC . O HEMA foi identificado nos extratos de todos os CIVs modificados por resina, e o iodobenzeno, somente no Vitrebond. Conclusão: Entre os CIVs estudados, o Vitrebond é o que libera mais componentes com potencial citotóxico.

Expression of the interleukin-10 signaling pathway genes in individuals with Down syndrome and periodontitis.

BACKGROUND: Individuals with Down syndrome (DS) have a higher prevalence and severity of periodontal disease, which cannot be explained by poor oral hygiene alone and is related to changes in the immune response. The aim of this study is to evaluate whether DS was associated with differential modulation of expression of genes associated with proinflammatory and anti-inflammatory responses in periodontal disease. METHODS: A total of 51 individuals were evaluated: 19 individuals with DS and periodontal disease (group 1), 20 euploid individuals with periodontal disease (group 2; positive control), and 12 euploid individuals without periodontal disease (group 3; negative control). Clinical periodontal evaluation and gingival biopsies were performed. Quantitative reverse transcription-polymerase chain reaction was used to determine expression levels of interleukin-10 (IL-10), the receptors IL-10RA and IL-10RB, intracellular adhesion molecule 1 (ICAM-1), interferon-γ-inducible protein 10 (IP-10), and the signaling intermediates Janus kinase 1, signal transducer and activator of transcription 3 (STAT-3), and suppressor of cytokine signaling 3 (SOCS-3). RESULTS: Expression of IL10, SOCS3, IP10, and ICAM1 mRNA in DS patients was significantly lower compared to euploid individuals with periodontal disease, whereas IL-10RB and STAT-3 mRNA levels were higher in individuals with DS. CONCLUSION: Reduced expression of IL-10 coupled with a possible increase of STAT3 activation (increase of STAT3 and reduction of SOCS3 mRNA) indicates an important modulation of the immune response, with attenuation of anti-inflammatory and increase of proinflammatory mediators. This modulation may be related to the increased prevalence and severity of periodontitis in individuals with DS.

Análise dos parâmetros clínicos periodontais e expressão genética de interferons alfa, gama e genes relacionados em indivíduos portadores de Síndrome de Down com doença periodontal / Periodontal clinical parameters analysis and genetics expression of Interferon-alpha, Interferon-gamma and genes related in individuais with Down Syndrome and periodontal disease

A doença periodontal (DP) em indivíduos com Síndrome de Down (SD) se desenvolve com alta prevalência, precocemente, de modo rápido e generalizado em comparação com indivíduos não-sindrômicos. Foi demonstrado que portadores da SD apresentam resposta imune diminuída em relação aos cromossomicamente normais. O objetivo desta pesquisa foi investigar diferenças nos parâmetros clínicos periodontais e níveis de expressão dos genes Interferon-gama (IFNG), Interferon-gama receptor 1 (IFNGR1), Interferon-gama receptor 2 (IFNGR2), Interferon-alfa (IFNA), Interferon-alfa receptor 1 (IFNAR1), Interferon-alfa receptor 2 (IFNAR2), Janus-quinase 1 (JAK1), Transdutor de sinal e ativador da transcrição 1 (STAT1) e Fator de regulação de interferon 1 (IRF1) em indivíduos com SD que apresentam ou não DP e em indivíduos cromossomicamente normais. Fizeram parte deste estudo 80 indivíduos entre 7 e 57 anos de idade subdivididos em 4 grupos: SD com DP (A); indivíduos com SD sem DP (B); indivíduos não-sindrômicos (Controle) com DP (C) e indivíduos Controle sem DP (D). A expressão gênica foi investigada por meio de quantificação relativa utilizando a técnica da Reação em Cadeia da Polimerase (PCR) em Tempo Real. Para o índice sangramento à sondagem (SS) não houve diferença entre os grupos A e C. A periodontite crônica localizada foi o tipo prevalente tanto entre indivíduos com SD como Controle. Considerando os parâmetros clínicos, não foram encontradas diferenças na periodontite crônica localizada entre os indivíduos com SD e Controle, assim como para a periodontite crônica generalizada. Com relação à análise genética, observou-se que indivíduos dos grupos com SD em relação aos grupos cromossomicamente normais (A+B-C+D) tiveram uma expressão de IFNG semelhante ao observado entre indivíduos do grupo Controle com DP (CD). No entanto, quando a DP acomete indivíduos com SD (A-B), o IFNG não apresenta uma resposta imune tão eficiente quanto para os indivíduos cromossomicamente normais (C-D). Na expressão do gene IFNA, indivíduos com SD (A+B-C+D) têm uma expressão consideravelmente menor que os indivíduos cromossomicamente normais com DP (C-D), indicando uma imunodeficiência em um importante mecanismo de controle da inflamação. Indivíduos com SD apresentaram expressão significativamente maior dos genes IFNGR2 e IFNAR1, os quais residem no cromossomo 21. A expressão de JAK1 nos indivíduos com SD independente de DP (A+B-C+D) foi acentuadamente menor, enquanto que a expressão do gene IRF1 foi significativamente maior nesses indivíduos em comparação aos indivíduos cromossomicamente normais (C-D). Portanto, a SD provavelmente pode interferir na cascata da via de sinalização do IFNG e IFNA contribuindo para uma menor eficiência do sistema imune de indivíduos frente à um estímulo inflamatório como a DP

Periodontal disease (PD) in individuals with Down Syndrome (DS) has an early, quickly and widespread onset and high prevalence when compared with individuals without the Syndrome. Only poor oral hygiene does not explain the severe periodontal destruction seen in DS patients. It has been shown that DS patients have a weaker immune response than people with normal number of chromosomes. The aim of this study was to investigate differences in periodontal clinical parameters and the expression levels of the genes Interferon-gamma (IFNG), Interferongamma receptor 1 (IFNGR1), Interferon-gamma receptor 2 (IFNGR2), interferon-alpha (IFNA), interferon-alpha receptor 1 (IFNAR1), Interferonalpha receptor 2 (IFNAR2), Janus-kinase 1 (JAK1), Signal transducers and activators of transcription 1 (STAT1) and Interferon regulatory factor 1 (IRF1) in DS patients with and without periodontal disease in comparison with chromossomically normal individuals. A total of 80 individuals aged 7 to 57 years participated in this study and were divided into 4 groups: DS with PD (A); DS without PD (B); individuals without DS (control) with PD (C) and individuals without DS (control) and without PD (D). A quantitative RT-qPCR was used to investigate gene expression. There was no difference between groups A and C regarding the bleeding on probing (BOP) index. The most prevalent type of periodontitis seen in this study was the localized chronic periodontitis, both in individuals with and without DS. Considering the clinical parameters, localized and generalized chronic periodontitis did not differ between individuals with and without DS. Regarding genetic analysis, individuals of the groups with DS in relation to the groups without DS (A+B-C+D) showed an IFNG expression similar to that seen among the individuals of groups control with PD (C-D). However, individuals with DS (A+B-C+D), the IFNG immune response is not as efficient as that of individuals without DS (C-D). Individuals of groups with DS (A+B) have a considerably smaller expression of the IFNA gene than those of groups without DS (C+D), indicating an immune deficiency in an important inflammation control mechanism. Individuals with DS presented a significantly greater expression of the genes IFNGR2 and IFNAR1, both located in chromosome 21. JAK1 expression in individuals with DS regardless of PD (A+B-C+D) was markedly smaller, while the expression of the IRF1 gene was significantly greater when compared with individuals without DS (C+D). Therefore, DS can probably interfere in the IFNG and IFNA signaling pathways, making the response of the immune system of individuals with DS to inflammatory stimuli, such as PD, less efficient