Juliana Barchelli Pinheiro

In Vitro Antimicrobial Activity of an Experimental Dentifrice Based on Ricinus Communis

This study evaluated the antimicrobial activity of a Ricinus communis-based experimental dentifrice for denture hygiene against the following standard strains: Staphylococcus aureus, Escherichia coli, Streptococcus mutans, Enterococcus faecalis, Candida albicans and Candida glabrata. The minimum inhibitory concentration (MIC) assay was performed with R. communis in pure oil at 2.5%. Only E. coli was not inhibited by R. communis, but the MIC (0.0781%) was effective against the other microorganisms. From these results it was determined the R. communis concentrations for experimental dentifrices, 1, 2, 5 and 10%, which were evaluated by the test-well diffusion in agar. The commercial dentifrices Colgate, Trihydral and Corega Brite were tested for comparative purposes. The diameter of the zones of bacterial growth inhibition produced around the wells was measured (in mm) with a rule under reflected light. Data were analyzed statistically by analysis of variance and Tukeys post-hoc test (α=0.05). Neither the commercial nor the experimental dentifrices were effective against E. coli. The experimental dentifrices containing R. communis at 2, 5 and 10% presented action against S. mutans, S. aureaus and E. faecallis. The experimental dentifrices showed no antimicrobial activity against Candida spp. and E. coli in any of the tested concentrations. Trihydral was the most effective. Comparing the experimental dentifrices, the product with 10% R. communis produced the largest zones of bacterial growth inhibition and had similar antimicrobial activity to the commercial dentifrices, except against S. aureus.

Microstructural characterization and evaluation of the properties of polymeric materials for maxillofacial prosthetics.

Abstract This study evaluated the Shore A hardness, colour and microstructural alterations of an experimental silicone for maxillofacial prostheses. As a control, the MDX 4-4210 silicone was used. Eighty specimens of each material were randomly divided into groups of pigmentation and ageing. For microstructural analysis by Thermogravimetry, Fourier Transform Infrared Spectroscopy and Differential Scanning Calorimetry, three specimens of each group were used. Anova and Tukey test (p < 0.05) was used in statistical analysis. There was significant difference in hardness depending on the materials, pigmentation and ageing and interaction between all the factors evaluated (p = 0.00). The colour change was significant due to ageing ( p = 0.00) and the interaction between the factors evaluated (p = 0.00). The microstructural analyses have shown that ageing methods and pigmentations did not cause structural alterations. The results suggest that the alterations in hardness and colour do not represent important structural changes.

Genomic identification of microbial species adhering to maxillofacial prostheses and susceptibility to different hygiene protocols

Abstract This study investigated the microbial colonization of maxillofacial prostheses and support tissues using the Checkerboard DNA–DNA hybridization method, and the efficacy of 0.12% chlorhexidine gluconate, 10% Ricinus communis solutions, or brushing, on colony forming unit (CFU) reduction in monospecies biofilms (Candida glabrata, Staphylococcus aureus, Streptococcus mutans, Escherichia coli, Enterococcus faecalis, and Pseudomonas aeruginosa) formed on two silicones (MDX 4-4210 and Bio-Skin). Biofilm was harvested from 43 maxillofacial prosthesis wearers for detection of 38 species of microorganisms. The CFU counts of the six above mentioned species were recorded after using the hygiene protocols. All 38 investigated species were identified in prostheses and tissues, with a higher prevalence in the prostheses. 0.12% chlorhexidine gluconate immersion showed the greatest antimicrobial effectiveness, followed by mechanical brushing protocols. MDX 4-4210 silicone produced lower CFU counts than Bio-Skin.

Oral Nodular Lesions in Patients with Sjögren’s Syndrome: Unusual Oral Implications of a Systemic Disorder

Sjögrens syndrome (SS) is a systemic chronic autoimmune disorder affecting the lacrimal and salivary glands. SS may manifest as primary SS (pSS) or secondary SS (sSS), the latter occurring in the context of another autoimmune disorder. In both cases, the dry eyes and mouth affect the patients quality of life. Late complications may include blindness, dental tissue destruction, oral candidiasis and lymphoma. This paper reports two cases of SS, each of them presenting unusual oral nodular lesion diagnosed as relapsed MALT lymphoma and mucocele. The importance of the diagnosis, treatment and management of the oral lesions by a dentist during the care of SS patients is emphasized, as the oral manifestations of SS may compromise the patients quality of life.