Análise in vivo do silicone vedando à infiltração de bactérias na interface pilar/implante / In vivo effectiveness of silicone gel sheets as a barrier at the inner microgap between

Neste estudo foi avaliada a eficácia da colocação de uma placa de silicone para tentar vedar a interface entre o pilar protético e a base de 22 implantes de hexágono externo osseointegrados, em 14 pacientes com boa condição clínica dos tecidos peri-implantares e portadores de coroas protéticas, em intervalo de tempo que variava de dois a 36 meses. As amostras foram coletadas desses microespaços antes, 30 e 90 dias após da inserção da membrana de silicone. Os DNA bacterianos foram extraídos e submetidos, em triplicata, à reação em cadeia da polimerase (PCR) com o uso de iniciadores específicos para os patógenos peri-implantares Aggregatibacter actinomycetemcomitans, Porphyromonas gingivalis, Prevotella intermedia e Tannerella forsythensis. Nas amostras iniciais foi constatada uma positividade de 48%, valor estatisticamente diferente do encontrado nas amostras coletadas após 30 (33%; p = 0,0652) e 90 dias (27%; p = 0,0081); aos 90 dias apresentou-se p < 0,05 indicando diferença significativa após a inserção da membrana. Assim, ficou evidenciado que a placa de silicone apenas reduziu, mas não impediu a penetração de nenhuma destas espécies no interior dos implantes de hexágono externo.

In this study the efficiency of the placing of a silicone membrane in order to seal the interface between the prosthetic abutment and the foundation of 22 external hexagonal connection implants was evaluated in 14 patients with good clinical conditions of the peri-implant tissues and implant-suppored prostheses varying from 2 to 36 months. The samples were collected in these microgaps before the insertion of the silicone membrane, 30, and 90 days later. The bacterial DNA were extracted and triplicated following polymerase chain reactio (PCR) with the use of specific initiators for the pathogenic peri-implant Aggregatibacter actinomycetemcomitans, Porphyr omonas gingivalis, Prevotella intermedia and Tannerella forsythensis species. In the initial samples, 48% of positive results were presented, a number statistically different from those found in samples collected after 30 (33%; p = 0,0652) and 90 days (27%; p = 0,0081); at 90 days, p values of < 0,05 were found, showing a significant difference after the membrane insertion. It was concluded that the silicone membrane just reduced but did not prevent infiltration of all tested species inside the external hexagon connections.

Detection of herpesviruses and periodontal pathogens in subgingival plaque of patients with chronic periodontitis, generalized aggressive periodontitis, or gingivitis.

BACKGROUND: Herpesviruses may be related to the etiology of aggressive periodontitis (AgP) and chronic periodontitis (CP) by triggering periodontal destruction or by increasing the risk for bacterial infection. This case-control study evaluated the presence of herpes simplex virus type I (HSV-1), Epstein-Barr virus type I (EBV-1), human cytomegalovirus (HCMV), Aggregatibacter actinomycetemcomitans (previously Actinobacillus actinomycetemcomitans), Porphyromonas gingivalis, Prevotella intermedia, and Tannerella forsythia (previously T. forsythensis) in patients with generalized AgP (AgP group), CP (CP group), or gingivitis (G group) and in healthy individuals (C group). METHODS: Subgingival plaque samples were collected with paper points from 30 patients in each group. The nested polymerase chain reaction (PCR) method was used to detect HSV-1, EBV-1, and HCMV. Bacteria were identified by 16S rRNA-based PCR. RESULTS: HSV-1, HCMV, and EBV-1 were detected in 86.7%, 46.7%, and 33.3% of the AgP group, respectively; in 40.0%, 50.0%, and 46.7% of the CP group, respectively; in 53.3%, 40.0%, and 20.0% of the G group, respectively; and in 20.0%, 56.7%, and 0.0% of the C group, respectively. A. actinomycetemcomitans was detected significantly more often in the AgP group compared to the other groups (P <0.005). P. gingivalis and T. forsythia were identified more frequently in AgP and CP groups, and AgP, CP, and G groups had higher frequencies of P. intermedia compared to the C group. CONCLUSION: In Brazilian patients, HSV-1 and EBV-1, rather than HCMV, were more frequently associated with CP and AgP.

Detection of Epstein-Barr virus and human cytomegalovirus in blood and oral samples: comparison of three sampling methods.

The purpose of this study was to identify and compare the presence of HCMV and EBV-1 in subgingival plaque, unstimulated saliva and peripheral blood of patients with chronic periodontitis. Forty patients diagnosed with chronic periodontitis (mean age, 41.7 years) were recruited. Unstimulated saliva, subgingival plaque and peripheral blood were collected from each patient and the DNA of each sample was isolated. The viruses were detected using the nested PCR technique. The detection frequency of EBV-1 in subgingival plaque, saliva and peripheral blood was 45%, 37.5% and 25%, respectively. HCMV was detected in 82.5% of subgingival plaque samples and peripheral blood and in 75% of salivary samples. The sensitivity for detecting EBV-1 in saliva and peripheral blood when EBV-1 was detected in subgingival plaque samples was low (22% and 27.7%, respectively) and the sensitivity for detecting HCMV in saliva and peripheral blood when compared to subgingival plaque was high (81.8% and 87.8%, respectively). There is a high agreement among the three sampling methods in detection of HCMV, but the detection of EBV-1 would require a combination of saliva and subgingival plaque sampling to avoid false negative results.

A importância do tratamento periodontal antes da colocação de implantes / Importance of previous periodontal treatment to implants placement

Evidências mostram um maior risco no sucesso da terapia com implantes quando a instalação é realizada em pacientes com diagnóstico de doença periodontal. A possibilidade de colonização de microrganismos na superfície dos implantes é real e pode comprometer a osteointegração. O objetivo desta revisão da literatura foi avaliar a importância do tratamento periodontal prévio à colocação de implantes. Após a análise de literatura, podemos concluir que é de suma importância a realização de tratamento periodontal prévio a instalação de implantes, assim diminuindo a possibilidade de ocorrência de periimplantite.

Diagnóstico clínico e complementar das doenças periimplantares / Clinical and complementary diagnosis of peri-implantitis diasease

O tratamento reabilitador por meio de implantes osseointegrados em pacientes parcialmente ou totalmente edentados tem sido utilizado na clínica odontológica com alta previsibilidade. O objetivo desta revisão da literatura foi o de avaliar os métodos de diagnósticos possíveis para condições que indiquem a presença de processo inflamatório ao redor de implantes. Foi possível concluir que a avaliação periódica da condição clínica dos tecidos moles ao redor dos implantes, as alterações na profundidade de sondagem, a mobilidade e a avaliação radiográfica são os melhores meios de detectar alterações no suporte ósseo.

Analysis of IL-1A(-889) and TNFA(-308) gene polymorphism in Brazilian patients with generalized aggressive periodontitis.

Generalized aggressive periodontitis (GAP) comprises a group of periodontal diseases characterized by the rapid destruction of periodontal tissues which affect young individuals who generally present no systemic disorders. Polymorphisms in the interleukin-1 (IL-1) and tumor necrosis factor-alpha (TNF-alpha) genes have been associated with an increased severity of chronic periodontitis. The objective of the present study was to evaluate the association between IL-1A (-889) and TNFA (-308) gene polymorphisms and GAP. One hundred nonsmoking subjects were selected, including 30 with GAP and 70 without periodontal disease. Gene polymorphisms were analyzed by the polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) technique. For IL-1 (-889), the frequency of genotype 1/1 was 54.3% in the control group and 56.7% in the study group. The frequency of genotype 1/2 was 37.1% in the control group and 40% in the study group. Genotype 2/2 was detected at a frequency of 8.6% and 3.3% in the control and study groups, respectively. For TNFA, genotype 1/1 was present in 68.6% of control subjects and in 80.0% of patients with GAP, while the frequency of genotype 1/2 was 27.1% in the control group and 20% in the study group. Genotype 2/2 was present in 4.3% of control subjects and was not detected in the study group. The frequencies of allele 1 and allele 2 of the IL-1A (-889) gene were 72.9% and 27.1%, respectively, in the control group and 76.7% and 23.3% in the GAP group. For the TNFA (-308) gene, the frequency of allele 1 was 82.15% in the control group and 90% in the study group, whereas the frequency of allele 2 was 17.85% in the control group and 10% in the study group. Statistical analysis revealed no significant difference in allele distribution for either gene between the two groups. No association was observed between GAP and IL-1A (-889) and TNFA (-308) gene polymorphisms in Brazilian patients.

Effect of tumor necrosis factor-alpha gene polymorphism on peri-implant bone loss following prosthetic reconstruction.

PURPOSE: The present study investigates the association between a specific polymorphism in the tumor necrosis factor (TNF)-alpha gene, consisting of allele 2 of TNF-alpha-308, and peri-implant bone loss following prosthetic reconstruction. MATERIALS AND METHODS: This case-control study included 36 patients (20 women, 16 men; mean age 46 years) who had used implant-supported prostheses for a minimum of 6 months and a maximum of 31 months. The patients were nonsmoking, white Caucasian Brazilians, in good general health, and were not receiving medication. In the case group, patients exhibited 1 or more implants with a diagnosis of peri-implant bone loss following prosthetic reconstruction; control patients had 1 or more healthy implants. RESULTS: Polymorphism in the TNF-alpha gene, allele 2 of TNF-alpha, was not associated with an increased risk for peri-implant bone loss following prosthetic reconstruction (P=0.19; chi2=1.71; df=1), although 21.1% of the subjects carried allele in the control group 2, and 41.2% carried allele 2 in the case group. CONCLUSIONS: Polymorphism in allele 2 of the TNF-alpha-308 gene is not associated with an increased risk for peri-implant bone loss following prosthetic reconstruction. However, further studies based on a greater number of patients are necessary.

Avaliação da associação entre o polimorfismo dos genes IL-1A (-889), IL1B (-511), IL-1B (+3954), IL-1RN (íntron 2-VNTR) e TNFA (-308) e a periodontite agressiva / Correlation between IL-1A (-889), IL-1B (-511), IL-1B (+3954), IL-1RN (intron 2-VNTR) and TNFA (-308) gene polymorphisms and aggressive periodontitis

A periodontite agressiva (PAg) compreende um grupo de doenças periodontais caracterizadas por rápida destruição dos tecidos periodontais, em indivíduos jovens e que geralmente não apresentam doenças sistêmicas. Estudos em populações e em famílias indicaram que fatores genéticos possuem influência na susceptibilidade à PAg. Os polimorfismos genéticos da interleucina-1 (IL-1) e do fator de necrose tumoral-α (TNF-α) foram associados com o aumento da severidade da periodontite. O objetivo deste estudo foi avaliar a associação entre o polimorfismo dos genes IL-1A (-889), IL-1B (-511), IL-1B (+3954), IL-1RN (íntron 2-VNTR) e TNFA (-308) e a PAg. O DNA genômico foi extraído de 150 indivíduos não fumantes, sendo 50 portadores de PAg e 100 indivíduos com periodonto saudável. O polimorfismo dos genes IL-1A (-889), IL-1B (-511), IL-1B (+3954) e TNFA (-308) foi analisado utilizando-se a técnica da reação em cadeia da polimerase e análise do polimorfismo de comprimento dos fragmentos de restrição (PCR-RFLP). O polimorfismo de número variável de repetições em tandem (VNTR) no íntron 2 do gene IL-1RN foi detectado pela técnica da PCR e análise do tamanho dos fragmentos. A análise estatística revelou que não houve diferença significante na freqüência dos genótipos e alelos, entre o grupo com PAg e os indivíduos com periodonto saudável, para IL-1A (-889), IL-1B (-511), IL-1B (+3954) e TNFA (-308) (p-valor>0.05%). Entretanto,houve diferença estatisticamente significante, entre os dois grupos, na distribuição dos genótipos para IL-1RN (íntron 2-VNTR) (teste Exato de Fisher; p-valor=0,021) e alelos (teste Exato de Fisher; p-valor=0,04). Os achados sugerem que o polimorfismo do gene IL-1RN (íntron 2-VNTR) está associado com a PAg na população estudada.

Aggressive periodontitis (AgP) is a type of periodontal disease characterized by a rapid destruction of the periodontal supporting tissues in young adults who are usually systemically well. Population and family studies indicate that genetic factors seem to have a strong influence on susceptibility to AgP. Genetic polymorphism at the interleukin-1 (IL-1) and tumor necrosis factor alpha (TNFA) were associated with the increase on the severity of periodontitis. This study aimed at finding a possible association between IL-1A (-889), IL-1B (-511), IL-1B (+3954), IL-1RN (intron 2-VNTR) and TNFA (-308) polymorphism in patients with aggressive periodontitis. Genomic DNA was extracted from the saliva of 150 nonsmoking subjects, 50 patients with AgP and 100 periodontal healthy subjects. All individuals were systemically healthy. The polymorphisms of IL-1A (-889), IL-1B (-511), IL-1B (+3954) and TNFA (-308) were analyzed by means of polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP). The polymorphism of a variable number tandem repeat (VNTR) in intron 2 of the IL-1RN gene was detected by PCR amplification and fragment size analysis. Statistical analysis revealed no significant difference in the IL-1A (-889), IL-1B (-511), IL-1B (+3954) and TNFA (-308) genotypes and allele frequencies between AgP patients and periodontal healthy subjects (p-value>0.05%). However, there were significant differences among the groups in the distribution of IL-1RN (íntron 2-VNTR) genotypes (Fisher’s exact test; p-value=0.021) and allelefrequencies (Fisher’s exact test; p-value=0.04). These findings suggest that IL-1RN (intron 2-VNTR) polymorphism is associated with AgP in the population presented here.

Efficacy of a herbal toothpaste on patients with established gingivitis--a randomized controlled trial.

The aim of this randomised, double blind controlled trial was to verify the efficacy of a herbal dentifrice on the reduction of plaque and gingivitis. Forty eight volunteers with established gingivitis were randomly assigned to either a test group (herbal dentifrice) or positive control group (dentifrice with triclosan and fluoride). The dentifrices were distributed in plain white tubes by an independent pharmacy, which revealed the contents of each tube only after the experimental period. Plaque and gingivitis assessments were carried out on baseline and after 28 days of product use. All examinations were conducted by the same calibrated investigator. Subjects were instructed to brush their teeth three times daily using their assigned dentifrice for 28 days. There was a significant reduction in plaque levels in both the test and control groups. However, there was no significant difference between the groups. A significant reduction in gingivitis was observed in both groups, although there was no significant difference between them. No adverse reactions were reported. The authors concluded that both dentifrices were effective in reducing plaque and gingivitis in subjects with established gingivitis.

Efficacy of a herbal toothpaste on patients with established gingivitis: a randomized controlled trial

O objetivo deste ensaio clínico aleatório duplo-cego foi verificar a eficácia de um dentifrício fitoterápico na redução de placa e gengivite. Quarenta e oito voluntários com gengivite estabelecida foram aleatoriamente alocados aos grupos teste (dentifrício fitoterápico) e controle positivo (dentifrício com triclosan e flúor). Os dentifrícios foram distribuídos em tubos brancos por uma farmácia independente, que revelou o conteúdo de cada tubo apenas após o final do período experimental. A aferição de placa e gengivite foi conduzida por um único examinador, previamente calibrado, no início e após 28 dias de uso do produto. Os sujeitos da pesquisa foram orientados a escovar os dentes com o dentifrício de seu grupo três vezes ao dia, por 28 dias. Houve redução significativa na quantidade de placa nos grupos teste e controle. No entanto, não houve diferença significativa entre os grupos. Os dois grupos experimentais apresentaram redução significativa nos níveis de gengivite, porém não houve diferença significativa entre eles. Não foram observadas reações adversas. Os autores concluíram que os dois dentifrícios foram eficazes na redução de placa e gengivite em indivíduos com gengivite estabelecida.

Effect of a 0.5 percent chlorhexidine gel on dental plaque superinfecting microorganisms in mentally handicapped patients

A randomized clinical trial was conducted to investigate the effect of a 0.5 percent chlorhexidine (CHX) gel on dental plaque superinfecting microorganisms in mentally handicapped patients. Thirty inmates from the institution "Casas André Luiz" were assigned to either test group (CHX gel, n = 15) or control group (placebo gel, n = 15). The gel was administered over a period of 8 weeks. Supragingival plaque samples were collected at baseline, after gel use (8 weeks) and 16 weeks after baseline. The presence of Gram-negative Enterobacteriaceae, Staphylococcus and yeasts was evaluated. No significant growth of any superinfecting microorganism was observed in the CHX group, when compared to the placebo group. The results indicated that the 0.5 percent chlorhexidine gel did not produce an undesirable shift in these bacterial populations

Effect of a 0.5% chlorhexidine gel on dental plaque superinfecting microorganisms in mentally handicapped patients.

A randomized clinical trial was conducted to investigate the effect of a 0.5% chlorhexidine (CHX) gel on dental plaque superinfecting microorganisms in mentally handicapped patients. Thirty inmates from the institution "Casas André Luiz" were assigned to either test group (CHX gel, n = 15) or control group (placebo gel, n = 15). The gel was administered over a period of 8 weeks. Supragingival plaque samples were collected at baseline, after gel use (8 weeks) and 16 weeks after baseline. The presence of Gram-negative Enterobacteriaceae, Staphylococcus and yeasts was evaluated. No significant growth of any superinfecting microorganism was observed in the CHX group, when compared to the placebo group. The results indicated that the 0.5% chlorhexidine gel did not produce an undesirable shift in these bacterial populations.

Prevalência de microrganismos superinfectantes na placa bacteriana supragengival de deficientes mentais institucionalizados / Prevalence of superinfecting microorganisms in the bacterial plaque of institucionalized subjects with cerebral palsy

Enterobactérias, estafilococos e leveduras säo microrganismos superinfectantes que podem ser encontrados na cavidade bucal de indivíduos com resposta imune deficiente, higiene pessoal inadequada ou expostos a antibioticoterapia prolongada. Sua presença tem sido associada a uma série de infecçöes bucais e extrabucais. Este estudo avaliou a prevalência desses microorganismos na placa bacteriana supragengival de 30 portadores de paralisia cerebral institucionalizados. Enterobactérias, estafilococos e leveduras foram encontrados, respectivamente, em 33 por cento, 13 por cento e 26 por cento dos pacientes. Enterobactérias representaram grande parte do total de bactérias isoladas em quatro pacientes (2,7 a 42 por cento), sendo que as espécies mais freqüentemente isoladas foram Serratia marcenscens e Klebsiella pneumoniae. A presença desses microorganismos na cavidade bucal pode ter implicaçöes terapêuticas, devido aos seus fatores de virulência