Influence of substratum position and acquired pellicle on Candida albicans biofilm

The purpose of this study was to evaluate the influence of the substratum position and the saliva acquired pellicle (AP) on Candida albicans biofilm development. Poly(methylmethacrylate) (PMMA) disks were fabricated and randomly allocated to experimental groups: HNP (disks placed in a horizontal position and uncoated by pellicle), VNP (disks placed in a vertical position and uncoated by pellicle), HCP (disks placed in a horizontal position and coated by pellicle), and VCP (disks placed in a vertical position and coated by pellicle). Disks were placed in a 24-well plate and a suspension of 107 cells/mL of Candida albicans was added to each well for biofilm development. The plates were aerobically incubated at 35°C. The biofilms were evaluated at 1.5 (adhesion time point), 24, 48, 72, and 96 hours. The number of viable cells was quantified in terms of the colony-forming units per milliliter (CFU/mL). Metabolic activity was measured by the XTT assay. The biofilm structure was analyzed by scanning electron microscopy. The data were analyzed by three-way ANOVA followed by Tukey's test, with significance set at 5%. The vertical groups showed less biofilm formation and lower metabolic activity than the horizontal groups (p< 0.05). Significant differences in cell viability and metabolic activity were observed between the adhesion and other time points (p< 0.05), but these variables were not affected by the presence of the pellicle (p > 0.05). It can be concluded that the substratum position influenced biofilm development.

Influence of substratum position and acquired pellicle on Candida albicans biofilm.

The purpose of this study was to evaluate the influence of the substratum position and the saliva acquired pellicle (AP) on Candida albicans biofilm development. Poly(methylmethacrylate) (PMMA) disks were fabricated and randomly allocated to experimental groups: HNP (disks placed in a horizontal position and uncoated by pellicle), VNP (disks placed in a vertical position and uncoated by pellicle), HCP (disks placed in a horizontal position and coated by pellicle), and VCP (disks placed in a vertical position and coated by pellicle). Disks were placed in a 24-well plate and a suspension of 107 cells/mL of Candida albicans was added to each well for biofilm development. The plates were aerobically incubated at 35°C. The biofilms were evaluated at 1.5 (adhesion time point), 24, 48, 72, and 96 hours. The number of viable cells was quantified in terms of the colony-forming units per milliliter (CFU/mL). Metabolic activity was measured by the XTT assay. The biofilm structure was analyzed by scanning electron microscopy. The data were analyzed by three-way ANOVA followed by Tukey's test, with significance set at 5%. The vertical groups showed less biofilm formation and lower metabolic activity than the horizontal groups (p<0.05). Significant differences in cell viability and metabolic activity were observed between the adhesion and other time points (p<0.05), but these variables were not affected by the presence of the pellicle (p>0.05). It can be concluded that the substratum position influenced biofilm development.

Diagnóstico clínico e protocolo de tratamento do desgaste dental não fisiológico na sociedade contemporânea / Clinical diagnosis and treatment protocol of non-physiological tooth wear in contemporary society

Os dentes humanos estão sujeitos a um desgaste fisiológico constante, durante toda a vida do indivíduo. Entretanto, esse desgaste pode ser acentuado por fatores extrínsecos e/ou intrínsecos, sendo resultado de três processos: abrasão (desgaste produzido pela interação entre os dentes e os outros materiais), atrição (desgaste através do contato do dente a dente) e erosão (dissolução do tecido duro por substâncias ácidas). Um processo adicional, abfração, pode potencializar o desgaste. As observações clínicas e experimentais mostram que os mecanismos individuais do desgaste atuam raramente sozinhos, embora interajam um com o outro. Essa interação parece ser o fator principal nos desgastes oclusal e cervical. Em função da natureza desse fenômeno, essas lesões podem gerar consequências catastróficas para a saúde bucal. Perdas de tecido podem resultar em sensibilidade, necrose pulpar, dor, perda de dimensão vertical e má aparência. O presente estudo visa orientar o cirurgião-dentista para estabelecer o diagnóstico diferencial entre os desgastes fisiológico e o anormal, esclarecendo o limite entre eles. Ainda, visa identificar sua etiologia e propor condutas clínicas preventivas e curativas. Nele, apresenta-se um caso clínico com lesões de erosão identificadas por meio do índice BEWE (Basic Erosive Wear Examination).

The human teeth are subject to wear a physiological constant throughout the life of the individual. However, this wear can be enhanced by extrinsic factors and / or intrinsic, being the result of three processes: abrasion (wear produced by interaction between teeth and other materials), attrition (wear through tooth to tooth contact) and erosion ( dissolution of hard tissue by acidic substances). An additional process, abfraction may promote wear. The clinical and experimental observations show that the individual wear mechanisms rarely act alone but interact with one another. This interaction, apparently, is the major factor in occlusal and cervical wear. Depending on the nature of this phenomenon, such injuries can have catastrophic consequences for oral health. Tissue loss can result in sensitivity, pulp necrosis, pain, loss of vertical. This study aims to guide the dentist to establish differential diagnosis between physiological and abnormal wear clarifying the boundary between them. Still, identifying its etiology and clinical management propose preventive and curative. We presented a clinical case with erosion lesions identified by index bewe (Basic Erosive Wear Examination).

Effect of a denture cleanser on the concentration of volatile sulphur compounds and denture biofilm in institutionalised elderly.

OBJECTIVE: To determine the effectiveness of a denture cleanser in reducing the concentration of volatile sulphur compounds (VSC) and its antimicrobial action. BACKGROUND: Micro-organisms from the denture biofilm can cause local and systemic disease and halitosis. Denture cleansers are important adjuncts in oral care, but there is limited investigation on their effect in malodour compounds. MATERIAL AND METHODS: Nineteen institutionalised elderly who wore at least an upper denture were selected; their VSC concentrations were measured and the denture biofilm was collected. In phase 1, the subjects wore their old denture and data were collected before (B0) and after 7(A1), 14(A2), 28(A3) days of continuous daily use of the denture cleanser. In phase 2, new dentures were inserted and measurements were made at 30(A1.1), 60(A2.2), 90(A3.3) days of treatment. RESULTS: The VSC concentration increased from B0 to A1 (p<0.05), but no differences were found for the others intervals of times. Total micro-organism data did not show a statistical difference between times in Phase I, but in Phase II, there was a statistical difference (p<0.05) and a progressive re-colonisation was observed. CONCLUSION: Within the limits of this study, it was concluded that the denture cleanser had no antimicrobial effect and VSC levels were not reduced.

Nutritional effects of implant therapy in edentulous patients--a systematic review.

PURPOSE: The aim of this study was to present all the relevant studies that have evaluated, with valid scientific methodology, the possible physical and nutrient intake improvement of edentulous subjects rehabilitated with removable and supported or retained implant denture, without restriction of suprastructure modalities, compared with those wearing conventional removable dentures. METHODS AND MATERIALS: Several electronic databases (Pubmed, Medline-Medline In-Process, Cochrane Library Database, Embase, and Lilacs) were searched, without language limitation. References from the selected articles were also hand searched. Abstracts which appeared to fulfill the initial selection criteria (comparison of nutritional state between conventional removable and supported or retained implant denture wearers) were selected by consensus and their original articles were then retrieved. Clinical trials that included anthropometric measurements or nutrient intake in removable and supported or retained implant denture wearers without syndrome and systemic influences, nor presenting surgical or other simultaneous treatment, which could affect the integrity during the evaluation period were finally selected. RESULTS: Only 5 articles met the selection criteria. Two studies (randomized clinical trials and prospective) found inadequate nutrient intake after treatment. One randomized clinical trial presented an improvement in nutritional state after treatment. One cross-sectional study showed an adequate nutritional state before and after treatment. These 4 studies found no significant difference between implant and conventional treatments. Finally, 1 cross-sectional study presented a difference between treatments, showing that the risk of malnutrition was higher for removable complete denture wearers. CONCLUSION: Considering the available evidence, the effect on the nutritional state in edentulous subjects treated with implant therapy is similar to the 1 obtained with conventional removable dentures. This effect does not necessarily mean an optimum nutritional state, which also depends on other factors not related to prosthodontic treatment.

Bruxismo do sono e sua associação com distúrbios do sono em policiais / Sleep bruxism and its associations with sleep disorders in policemen

O bruxismo do sono é uma das atividades parafuncionais mais abordados na Odontologia, especialmente devido a questões controversas quanto à sua prevalência e etiologia. Os estudos realizados na área conseguem, tão somente, amenizar seu potencial destrutivo, mas não estabelecem, todavia, uma relação direta entre causa e efeito. A literatura considera atualmente o estresse, a fisiologia do sono, algumas drogas e, em menor escala, a oclusão, como fatores desencadeadores deste comportamento parafuncional. O objetivo deste trabalho foi investigar a relação entre bruxismo do sono e distúrbios do sono, em policiais militares da cidade de São Luís-MA. Os resultados revelaram que não houve associação significante entre bruxismo do sono e distúrbios do sono (p=0,07). Conclui-se, portanto que apesar de o bruxismo ocorrer duranteo sono, ele não interfere na qualidade do mesmo.

Associação entre bruxismo e estresse em policiais militares / Association between bruxism and emotional stress in military policemen

Objetivo: O trabalho teve por objetivo mensurar a prevalência de bruxismo e de estresse em policiais militares e sua possível associação. Metodologia: Um estudo transversal foi conduzido na cidade de São Luís, MA, com membros da Polícia Militar do Estado do Maranhão. Foram selecionados 81 policiais do sexo masculino (idade média = 33,5 anos), os quais foram diagnosticados como bruxistas de acordo com os critérios clínicos: presença de facetas de desgaste dental associadas ao auto-relato de ranger de dentes, sensibilidade dolorosa nos músculos masseter e temporal e desconforto na musculatura da mandíbula ao despertar. Para o diagnóstico de estresse foi aplicado o Inventário de Sintomas do Stress (Stress Symptoms Inventory SSI). Resultados: A prevalência de bruxismo foi de 33,3% e a de estresse emocional, 13,6%. A prevalência de estresse em indivíduos com bruxismo foi significativamente maior em relação aos indivíduos sem bruxismo (teste qui-quadrado, P= 0,003). Conclusão: Dentro das limitações do estudo, concluiu-se que o estresse esteve associado à presença de bruxismo nesta amostra de policiais militares.

Purpose: The aim of this study was to assess the prevalence of bruxism and emotional stress in military policemen and test their association. Methods: A cross-sectional study was conducted in members of the Military Police of the State of Maranhão in São Luís, MA. Sample was composed by 81 male subjects (mean age = 33.5 years). Bruxism was diagnosed according to clinical criteria - presence of aligned wear facets associated with at least one of the following signs and symptoms: selfreport of bruxism grinding sounds, pain to palpation of the masseter and temporal muscles, report of morning masticatory muscle discomfort and/or masseter muscle hypertrophy. To diagnose stress the Stress Symptoms Inventory was applied. Results: The prevalence of bruxism was 33.3% and frequency of emotional stress was 13.6%. The stress prevalence in individuals with bruxism was significantly higher than that in subjects without bruxism (Chi-square test, P=0.003). Conclusion: Within the limitations of this study, it can be concluded that stress was associated with bruxism in this sample of policemen.