Prevalence of microorganisms in root canals of human deciduous teeth with necrotic pulp and chronic periapical lesions

O objetivo deste estudo foi avaliar, por meio de cultura bacteriológica, a prevalência de microorganismos em 31 canais radiculares de dentes decíduos humanos com necrose pulpar e lesão periapical. O material, colhido dos canais radiculares após a realização da cirurgia de acesso, foi submetido ao processamento microbiológico para a determinação das unidades formadoras de colônia de microorganismos. Os resultados mostram que os microorganismos anaeróbios foram quantificados em 96,7% dos casos, os bacilos pigmentados de negro (BPB) em 35,5%, os aeróbios em 93,5%, os estreptococos em 96,7% e os S. mutans em 48,4%. Assim, pôde-se concluir que a infecção em canais radiculares de dentes decíduos humanos portadores de necrose pulpar e lesão periapical é polimicrobiana, com grande quantidade de microorganismos e maior prevalência de estreptococos e microorganismos anaeróbios.The objective of this study was to evaluate bacterial prevalence in 31 root canals of human deciduous teeth with necrotic pulp and periapical lesions using bacterial culture. After crown access, the material was collected using absorbent paper points for microbiological evaluation and determination of colony forming units (CFU). Anaerobic microorganisms were found in 96.7% of the samples, black-pigmented bacilli in 35.5%, aerobic microorganisms in 93.5%, streptococci in 96.7%, and S. mutans in 48.4%. We concluded that in human deciduous teeth root canals with necrotic pulp and periapical lesions the infection is polymicrobial, with a large number of microorganisms and a predominance of streptococci and anaerobic microorganisms

Antimicrobial activity of dentifrices uused in children's oral hygine: in vitro study

O objetivo deste trabalho foi avaliar a ação antimicrobiana de diferentes dentifrícios utilizados na higiene bucal infantil frente a 16 cepas de S. mutans isoladas da saliva de crianças. Os dentifrícios foram classificados quanto à presença/ concentração de flúor e associação ou não a produtos naturais em: A- fluoreto de sódio- 1100 ppm; B- fluoreto de sódio- 1000 ppm e própolis; C- fluoreto de sódio- 500 ppm; D-fluoreto de sódio 500 ppm e extrato de malva; E- monofluorfosfato de sódio- 0,76%; F- monofluorfosfato de sódio- 1000 ppm; G- aloe-vera/própolis/ complexo cobre-clorofila. A atividade antimicrobiana foi avaliada pelo método da difusão em Agar (técnica do disco). Após o preparo da suspensão microbiana no padrão 0,5 da escala de McFarland e semeadura por inundação, 20 µl do sobrenadante de cada dentifrício foram pipetados em discos de papel e aplicados sobre o meio de cultura BHIA. Os halos de inibição ao redor dos discos foram medidos e os valores analisados pelo teste de Quade. Os dentifrícios A, B e G inibiram 100% das cepas, revelando ação antimicrobiana significativamente maior que os demais dentifrícios avaliados (pThe purpose of this study was to evaluate the antimicrobial activity of different dentifrices used in children's oral hygiene against 16 S. mutans strains of isolated from children's saliva. The dentifrices were categorized according to the presence/concentration of fluoride and addition or not of natural products in their composition, as follows: A- sodium fluoride- 1100 ppm; B- sodium fluoride- 1000 ppm and propolis; C- sodium fluoride- 500 ppm; D-fluoride sodium 500 ppm and mallow extract; E- 0.76% sodium monofluorophosphate; F-sodium monofluorophosphate -1000 ppm; G- aloe-vera/propolis/copper-chlorophyll complex. The antimicrobial activity was evaluated using the agar diffusion method (disc technique). After preparation of the microbial suspension according to the 0.5 density of McFarland scale and seeding, 20 µl of the supernatant of each dentifrice were pipetted in paper discs and taken to BHIA culture medium. The inhibition halos surrouding the discs were measured and the values were analyzed statistically using the Quade test. Dentifrices A, B and G inhibited 100% of the strains, denoting a significantly higher antimicrobial activity than the other dentifrices evaluated (

Effect of Chlorhexidine on Denture Biofilm Accumulation

Purpose: Adequate denture hygiene can prevent and treat infection in edentulous patients, who are frequently elderly and have difficulty brushing their teeth. This study evaluated the efficacy of complete denture biofilm removal using a chlorhexidine solution in two concentrations: 0.12% and 2.0%. Materials and Methods: Sixty complete denture wearers participated in a trial for 21 days after receiving brushing instructions. They were distributed into three groups, according to the tested solution and regimen (n = 20): (G1) Control (daily overnight soaking in water); (G2) daily immersion at home in 0.12% chlorhexidine for 20 minutes after dinner; and (G3) a single immersion in 2.0% chlorhexidine for 5 minutes at the end of the experimental period, performed by a professional. Biofilm coverage area (%) was quantified on the internal surface of maxillary dentures at baseline and after 21 days. Afterward, the differences between initial and posttreatment results were compared by means of the Kruskal-Wallis test (a = 0.05). Results: Median values for biofilm coverage area after treatment were: (G1) 36.0%; (G2) 5.3%; and (G3) 1.4%. Differences were significant (KW = 35.25; p < 0.001), although G2 and G3 presented similar efficacy in terms of biofilm removal. Conclusions: Both chlorhexidine-based treatments had a similar ability to remove denture biofilm. Immersion in 0.12% or 2.0% chlorhexidine solutions can be used as an auxiliary method for cleaning complete dentures.Sao Paulo Research Foundation (FAPESP) [2005/55705-2

The effectiveness of chemical denture cleansers and ultrasonic device in biofilm removal from complete dentures

Adequate denture hygiene can prevent and treat infection in edentulous patients. They are usually elderly and have difficulty for brushing their teeth. OBJECTIVE: This study evaluated the efficacy of complete denture biofilm removal using chemical (alkaline peroxide-effervescent tablets), mechanical (ultrasonic) and combined (association of the effervescent and ultrasonic) methods. MATERIAL AND METHODS: Eighty complete denture wearers participated in the experiment for 21 days. They were distributed into 4 groups (n=20): (1) Brushing with water (Control); (2) Effervescent tablets (Corega Tabs); (3) Ultrasonic device (Ultrasonic Cleaner, model 2840 D); (4) Association of effervescent tablets and ultrasonic device. All groups brushed their dentures with a specific brush (Bitufo) and water, 3 times a day, before applying their treatments. Denture biofilm was collected at baseline and after 21 days. To quantify the biofilm, the internal surfaces of the maxillary complete dentures were stained and photographed at 45º. The photographs were processed and the areas (total internal surface stained with biofilm) quantified (Image Tool 2.02). The percentage of the biofilm was calculated by the ratio between the biofilm area multiplied by 100 and the total area of the internal surface of the maxillary complete denture. RESULTS: The Kruskal-Wallis test was used for comparison among groups followed by the Dunn multiple-comparison test. All tests were performed respecting a significance level of 0.05. Significant difference was found among the treatments (KW=21.18; P<0.001), the mean ranks for the treatments and results for Dunn multiple comparison test were: Control (60.9); Chemical (37.2); Mechanical (35.2) and Combined (29.1). CONCLUSION: The experimental methods were equally effective regarding the ability to remove biofilm and were superior to the control method (brushing with water). Immersion in alkaline peroxide and ultrasonic vibration can be used as auxiliary agents for cleaning complete dentures