Influence of thickness and aging on the mechanical properties of provisional resin materials.

This study aimed to evaluate the flexural strength (FS) and modulus of elasticity (ME) of 2 provisional resins at different thicknesses and after different storage periods. A total of 80 specimens were made of 2 provisional restorative materials (n = 40): Dencôr (DC) or Protemp 4 (PT). The specimens in each material group were prepared in 2 different thicknesses (n = 20): 1.5 mm or 2.0 mm. The groups were further subdivided by storage time (n = 10 per material thickness per time): 7 days or 3 months. A 3-point bending test was performed with a universal testing machine. Data were submitted to 3-way analysis of variance followed by a post hoc Tukey test (α = 0.05). Regarding the interaction of material and thickness, the 2.0-mm-thick DC specimens presented a significantly lower mean FS (41.08 MPa) than the other groups (P < 0.05). Regarding the interaction of material and storage time, PT after 3 months presented a significantly higher mean FS (75.51 MPa) than the other groups and periods (P < 0.05). Regardless of the material, the highest mean ME was found in the 1.5-mm-thick group after 3 months (2.24 GPa) (P < 0.05). The lowest ME values were found in the 2.0-mm-thick specimens after both storage times (7 days, 0.88 GPa; 3 months, 1.09 GPa), which were not significantly different from each other (P > 0.05). The correlation between FS and ME was direct and positive (R2 = 0.51; P < 0.001), independently of the variables (material, thickness, and time). Therefore, 2.0-mm-thick PT specimens presented the highest values of FS, mainly after 3 months. The ME was higher after 3 months (1.5-mm-thick specimens), regardless of the material. In addition, the higher the FS, the higher the ME of the material.

Comparison of denture microwave disinfection and conventional antifungal therapy in the treatment of denture stomatitis: a randomized clinical study.

OBJECTIVE: The aim of this study was to compare the effectiveness of denture microwave disinfection and antifungal therapy on treatment of denture stomatitis. STUDY DESIGN: Sixty denture wearers with denture stomatitis (3 groups; n = 20 each), were treated with nystatin or denture microwave disinfection (1 or 3 times/wk) for 14 days. Mycologic samples from palates and dentures were quantified and identified with the use of Chromagar, and clinical photographs of palates were taken. Microbiologic and clinical data were analyzed with the use of a series of statistical tests (α = .05). RESULTS: Both treatments similarly reduced clinical signs of denture stomatitis and growth on palates and dentures at days 14 and 30 (P > .05). At sequential appointments, the predominant species (P < .01) isolated was C. albicans (range 98%-53%), followed by C. glabrata (range 22%-12%) and C. tropicalis (range 25%-7%). CONCLUSIONS: Microwave disinfection, at once per week for 2 treatments, was as effective as topical antifungal therapy for treating denture stomatitis.

Denture stomatitis treated with photodynamic therapy: five cases.

OBJECTIVE: Photodynamic therapy (PDT) is an effective method for Candida spp. inactivation in vitro and in vivo, but as yet, no clinical trial has been conducted. This report describes 5 cases of denture stomatitis (DS) treated with PDT. STUDY DESIGN: Five subjects with clinical and microbiologic diagnosis of DS were submitted to 6 sessions of PDT 3 times a week for 15 days. In each session, patients' dentures and palates were sprayed with 500 mg/L Photogem, and, after 30 minutes of incubation, irradiated by light-emitting diode light source at 455 nm (37.5 and 122 J/cm(2), respectively). Cultures of Candida spp. from dentures and palates and standard photographs of the palates were taken at baseline (day 0), at the end of the treatment (day 15), and at follow-up time intervals (days 30 and 60). RESULTS: Four patients showed clinical resolution of DS (no inflammation) after PDT sessions, and only 1 subject demonstrated reduction in palatal inflammation. Recurrence of DS was observed in 2 patients during the follow-up period. CONCLUSIONS: PDT appears to be an alternative treatment for DS.

Candida spp. prevalence in well controlled type 2 diabetic patients with denture stomatitis.

OBJECTIVE: The aim of this study was to compare the prevalence of Candida spp. in diabetics and nondiabetics with and without denture stomatitis (DS). STUDY DESIGN: Mycologic samples were taken from the dentures of 90 healthy subjects (control group [CG]), 80 denture stomatitis nondiabetics (DSND), and 40 denture stomatitis diabetics (DSD; well controlled type 2) for identification of Candida spp. Results were analyzed by Fisher exact test, Bonferroni-corrected confidence interval, and χ(2) test (α = .05). RESULTS: Candida albicans was the predominant species isolated (81.9%; P < .016), with C. tropicalis and C. glabrata demonstrating similar prevalence (15.71% and 15.24%, respectively). The prevalence of C. albicans and C. tropicalis in the DS groups were significantly higher (P < .01) than in the CG. The prevalence of C. tropicalis significantly increased with the highest degree of inflammation (P < .05). CONCLUSIONS: The prevalence of Candida spp. was similar between diabetic and nondiabetic patients with DS. Candida tropicalis may play a role in the progression of DS.

Desinfecção de próteses totais por micro-ondas: efeito da frequência de irradiação no tratamento da estomatite protética / Disinfection of complete dentures using microwaves: effect of irradiation frequency in the treatment of denture stomatitis

A estomatite protética é uma infecção fúngica que acomete entre 60% e 72% dos indivíduos portadores de próteses removíveis, sobretudo idosos do gênero feminino. Atualmente, a desinfecção de próteses totais por meio da irradiação por micro-ondas tem sido recomendada para tratamento e prevenção da estomatite protética. Considerando esses aspectos, esse estudo in vivo avaliou a efetividade da frequência da desinfecção de próteses totais por micro-ondas (3 min/650 W) em relação à terapia antifúngica tópica para o tratamento da estomatite protética, além de verificar a prevalência de Candida nos pacientes avaliados. Para isso, foram selecionados 60 indivíduos, portadores de próteses totais superiores e com diagnóstico clínico de estomatite protética. Esses pacientes foram aleatoriamente distribuídos em 3 grupos (n=20), de acordo com o tratamento instituído: Terapia Antifúngica Tópica (Grupo I) - utilização de nistatina (suspensão oral, 100.000 UI/mL), 4 vezes ao dia durante 15 dias; Irradiação por Micro-ondas ­ imersão das próteses totais em água e irradiação das próteses por micro-ondas durante 3 minutos a 650 W, 1 ou 3 vezes por semana (Grupos II e III, respectivamente) por um período de 15 dias. Para avaliação da efetividade dos tratamentos instituídos, foram realizadas culturas micológicas quantitativas e identificação das espécies de Candida, utilizando-se o meio CHROMagar Candida, análise de microcultivo, teste de triagem em caldo hipertônico e o sistema bioquímico de identificação ID 32C. Coletas de biofilme das superfícies internas das próteses totais superiores e das mucosas palatinas de todos os pacientes, foram realizadas previamente ao tratamento (dia 0) e após 15 dias do seu início. Com o objetivo de avaliar a efetividade dos tratamentos em longo prazo, a quantificação de colônias viáveis de Candiada spp. foram repetidas após 30, 60 e 90 dias do início do tratamento. Em cada consulta (dias 0, 15, 30, 60 e 90) foi realizada ainda, uma avaliação clínica por meio de fotografias intrabucais da mucosa palatina dos indivíduos. Os resultados obtidos por meio das culturas micológicas quantitativas foram analisados estatisticamente pelos testes de Wilcoxon e de Kruskal-Wallis (α=0,05). Os resultados das identificações bioquímicas das espécies de Candida foram interpretados por meio de uma análise qualitativa. Para as avaliações clínicas foi utilizado o índice Kappa de concordância e em seguida, a análise qualitativa duplo-cega das fotografias intrabucais. No décimo quinto dia de avaliação os tratamentos aplicados nos grupos Grupos I, II, III foram efetivos (p<0,05) para redução das células viáveis (valores de ufc/mL) de Candida spp. referentes à mucosa palatina e a superfície interna das próteses totais superiores. Enquanto, após 30, 60 e 90 dias do início dos tratamentos os resultados demonstraram em todos os grupos avaliados (Grupos I, II, III), um aumento gradativo nos valores de ufc/mL, porém sem diferenças estatisticamente significativa entre os períodos de avaliação. A comparação entre grupos de tratamento indicou aos 90 dias, uma diferença estatisticamente significativa (p<0,05) entre o Grupo III e os demais grupos (I e II). As identificações bioquímicas revelaram que as espécies predominantes em ambos os sítios de coleta foram a C. albicans, a C. tropicalis e a C. glabrata. No término do tratamento foi verificado um aumento na frequência de C. albicans no Grupo I. Enquanto, para os Grupos II e III a frequência de C. glabrata aumentou e a de C. tropicalis diminuiu. A avaliação das fotografias intrabucais indicou melhora nos sinais clínicos da estomatite protética no 15º dia em todos os Grupos do estudo, porém nos períodos subsequentes de avaliação áreas eritematosas tornaram-se visíveis na mucosa palatina de muitos indivíduos. A redução na frequência da desinfecção de próteses totais por micro-ondas (3 min/650 W) foi tão efetiva quanto à terapia antifúngica tópica (nistatina) para o tratamento da estomatite protética

Denture stomatitis is a fungal infection that affects 60% to 72% of individuals who use removable dentures, primarily elderly women. Currently, the disinfection of complete dentures using microwave irradiation has been recommended to treat and prevent denture stomatitis. Considering these aspects, this in vivo study evaluated the effectiveness of the frequency of complete denture disinfection using microwaves (3 min/650 W) compared to antifungal therapy for the treatment of denture stomatitis. It also verified the prevalence of Candida spp. in the evaluated patients. This study used a sample of 60 healthy individuals who use complete upper dentures and have received a clinical diagnosis of denture stomatitis. Patients were randomly distributed into three groups (n=20), based on the treatment used: Topical Antifungal Therapy (Group I) ­ use of nystatin (oral suspension, 100.000 UI/mL), four times a day for 15 days; Irradiation with Microwaves ­ irradiation of the dentures by microwaves for three minutes at 650 W, one time or three times per week (Groups II and III, respectively) for a period of 15 days. In order to evaluate the effectiveness of the treatments used, quantitative mycological cultures were collected and the Candida species were identified using the CHROMagar Candida method, microculture analysis, screening test in hypertonic broth and the ID 32C biochemical identification system. Biofilm samples were collected from the inner surfaces of the complete upper dentures and from the palatal mucosa of all patients before (day 0) and after 15 days of treatment. In order to evaluate the effectiveness of the treatments over the long term, the quantification of the viable Candiada spp. colonies was repeated 30, 60 and 90 days after starting the treatment. For each consultation (days 0, 15, 30, 60 and 90), a clinical evaluation was also performed through intra-oral photography of the palatal mucosa of the individuals. The results from quantitative mycological cultures were statistically analyzed using Wilcoxon and Kruskal-Wallis tests (α=0.05). Biochemical identification results for the Candida species were interpreted through qualitative analysis. The Kappa concordance coefficient was used for the clinical evaluations, and then a qualitative doubleblind analysis was conducted on the intra-mouth photograph. On the 15th day of the evaluation, the treatments applied to Groups I, II and III were effective (p<0.05) in reducing the mycological cultures (ufc/mL values) of Candida spp. associated with the palatal mucosa and inner surface of the complete upper dentures. However, 30, 60 and 90 days after starting the treatment, all evaluated groups (GI, GII, GIII) demonstrated a gradual increase in the values of ufc/mL, although without statistically significant differences between the evaluation periods. The comparison among treatment groups indicated no statistically significant differences (p<0.05) among groups, except between Group III and the other groups (GI and GII) at 90 days. The biochemical identifications revealed that the predominant species in both collection sites were C. albicans, C. tropicalis and C. glabrata. Furthermore, an increase in the frequency of C. albicans was found at the end of the treatment in Group I. The frequency of C. glabrata increased for Groups II and III and that of C. tropicalis decreased. The evaluation of the intra-oral photography indicated an improvement in the clinical signs of denture stomatitis on the 15th day in all study groups, although erythematous areas became visible on the palatal mucosa of many individuals during the periods following the evaluation. Based on the results of this study, it can be concluded that, regardless the frequency of irradiation, microwave disinfection (3 min/650 W) was as effective as topic antifungal therapy for treating denture stomatitis

A saúde bucal na terceira idade / Oral health status of the elderly

A odontologia tem se deparado com um aumento no tamanho e na idade da população idosa sendo, ainda, que uma grande parte desta população é completamente desdentada. O edentulismo pode afetar substancialmente a saúde bucal e geral do indivíduo bem como sua qualidade de vida. Sendo assim, a proposta deste artigo foi avaliar a relação entre o uso de próteses totais, as condições de saúde bucal e as condições de saúde geral de pessoas em fase de envelhecimento. Em indivíduos nesta fase, há uma prevalência de doenças crônicas, de disfunções psicossociais e físicas e grande utilização de fármacos, os últimos podendo causar inúmeros efeitos colaterais e prejudicar tanto a saúde da boca como a saúde sistêmica do idoso. Devido a essas considerações, é necessário que os cirurgiões dentistas avalie mas condições de saúde bucal de seus pacientes idosos sob o olhar do inter-relacionamento destas com as condições de saúde geral e qualidadede vida do indivíduo.

The dental profession is facing an increase in size and age of theolder population. In addition, there is a large number of older peoplewho is completely edentulous. Edentulism can substantially affectoral and general health as well as overall quality of life. The purposeof this article was to investigate in dental literature the relationshipsamong denture wearing, oral health status and general healthconditions in elderly people. Chronic disease, psychosocial andphysical dysfunction and complex pharmacotherapeutic regimensare prevalent in older people. The last ones may have many adverseeffects on the oral health and on the general health of the elderly.In this context dentists must evaluate the oral health status of theelderly and its relationship with the general health and the overallquality of life.

Técnicas de moldagem em prótese sobre implantes / Impressions techniques for dental implants

A obtenção de um modelo de trabalho fiel em implantodontia está relacionada principalmente às técnicas de moldagem e aos materiais utilizados. O objetivo desta revisão de literatura é apresentar os materiais e as técnicas de moldagem mais precisas utilizados em prótesesimplantossuportadas. Com base nos artigos revisados, verifica-se que a técnica de moldagem mais precisa é a de arrasto com transferentes quadrados unidos por meio de barras pré-fabricadas de resina auto ou fotopolimerizável associada a um material elastomérico (poliéter ou silicona por adição).

The accuracy of dental implants is related to impression materials and dental impression techniques. This paper presents, according to scientific literature, the most precise impression materials and dental impression techniques used in implant prosthodontic rehabilitations. Based on the reviewed manuscripts, an elastomeric material (polyether and polyvinyl siloxane) associated to an open-tray pick-up impression technique (square transfer copings splinted) should be used in implant-supported dental prosthesis.

Effectiveness of microwave irradiation on the disinfection of complete dentures.

PURPOSE: The purpose of this study was to evaluate the effectiveness of microwave irradiation on the disinfection of simulated complete dentures. MATERIALS AND METHODS: Eighty dentures were fabricated in a standardized procedure and subjected to ethylene oxide sterilization. The dentures were individually inoculated (10(7) cfu/mL) with tryptic soy broth (TSB) media containing one of the tested microorganisms (Candida albicans, Streptoccus aureus, Bacillus subtilis, and Pseudomonas aeruginosa). After 48 hours of incubation at 37 degrees C, 40 dentures were individually immersed in 200 mL of water and submitted to microwave irradiation at 650 W for 6 minutes. Forty nonirradiated dentures were used as positive controls. Replicate aliquots (25 microL) of suspensions were plated at dilutions of 10(-3) to 10(-6) on plates of selective media appropriate for each organism. All plates were incubated at 37 degrees C for 48 hours. TSB beakers with the microwaved dentures were incubated at 37 degrees C for 7 more days. After incubation, the number of colony-forming units was counted and the data were statistically analyzed by Kruskal-Wallis test (alpha = .05). RESULTS: No evidence of growth was observed at 48 hours for S. aureus, B. subtilis, and C. albicans. Dentures contaminated with P. aeruginosa showed small growth on 2 plates. After 7 days incubation at 37 degrees C, no growth was visible in the TSB beakers of S. aureus and C. albicans. Turbidity was observed in 3 broth beakers, 2 from P. aeruginosa and 1 from B. subtilis. CONCLUSION: Microwave irradiation for 6 minutes at 650 W produced sterilization of complete dentures contaminated with S. aureus and C. albicans and disinfection of those contaminated with P. aeruginosa and B. subtilis.