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BACKGROUND: Polymethylmethacrylate (PMMA) is the most used material for the manufacturing of eye prostheses. OBJECTIVES: To investigate the cytotoxicity of different cleaning agents for ocular prostheses on human conjunctival cells. MATERIAL AND METHODS: Six groups of specimens were created (saline, soap, 4% chlorhexidine, hydrogen peroxide, 1% triclosan, and citronella oil). Three specimens were made for each disinfectant at each disinfection period (1, 7, 15, 30, 60, and 90 days), totaling 108 specimens. Thus, the specimens were disinfected, with different disinfectants, for different periods of time. After each disinfection process, the specimens were washed with sterile distilled water. A human conjunctival cell line was grown on the acrylic resin specimens and then cytotoxicity tests (MTT and Neutral Red (NR)) were performed. A negative control (untreated cell cultures) and positive control (Tween 20) were created. Two-way analysis of variance (ANOVA) and Bonferroni test were performed (p < 0.05). RESULTS: For the MTT and NR tests, when there was a significant difference between the disinfectant and negative control, the disinfectant generated a significant reduction in cell proliferation most of the time. CONCLUSIONS: All reductions in cell proliferation caused by the disinfectants were clinically acceptable. All disinfectants tested in this study were found to be non-cytotoxic to human conjunctival cells.

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Background. Implant fractures can cause difficult problems for patients and dentists. This systematic review aimed to determine the influence of some implant parameters on the occurrence of their fracture and to determine the incidence of fractures reported in recent years. Methods. A search was conducted in Pubmed database, from which 12 studies published in the last 12 years were selected. Results. This review reported a 2% incidence of implant fracture. Most implants had been in function between 3 and 4 years until fracture. The studies did not provide necessary information to establish a relationship between the different parameters of implants and the incidence of fractures. Conclusion. Thus, the indication of type, diameter and length of an implant and the bone quality in the region receiving it should be studied and accurately examined for each individual case in order to avoid future failures.

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BACKGROUND: The aim of this study was to verify, through self-assessment questionnaires, the influence of implant-supported prosthesis in salivary flow and anxiety of patients rehabilitated with them. MATERIALS AND METHODS: Visual analog scale (VAS) questionnaire about xerostomia and State-Trait Anxiety Inventory were applied before (T1) and after 2 days (T2) and 3 weeks (T3) of prostheses installation. The study included patients rehabilitated with implant-supported prostheses containing three or more dental elements. A total of 17 patients were evaluated. RESULTS: In VAS questionnaire, there was a significant increase in the difficulty of speaking and swallowing with dry mouth. The other VAS questions showed no statistically significant difference, indicating no changes in patients' salivary flow. CONCLUSIONS: It was concluded that the installation of implant-supported prostheses does not lead to major changes in patients' perception about their salivary flow and psychological state, causing no improvement or worsening in the characteristics evaluated.

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OBJECTIVE: The purpose of this study was to evaluate the influence of surface roughness in biofilm formation of four microorganisms (Staphylococcus epidermidis, Staphylococcus aureus, Enterococcus faecalis, and Candida albicans) on acrylic resin surface of ocular prostheses. MATERIALS AND METHODS: Acrylic resin samples were divided into six groups according to polishing: Group 1200S (1200 grit + silica solution); Group 1200; Group 800; Group 400; Group 120 and Group unpolished. Surface roughness was measured using a profilometer and surface images obtained with atomic force microscopy. Microbial growth was evaluated after 4, 24, and 48 hours of incubation by counting colony-forming units. STATISTICAL ANALYSIS USED: For roughness, it was performed 1-way ANOVA and parametric Tukey test α5% (P ≤ 0.05). For CFU data found, it was applied Kruskal-Wallis and Mann-Whitney tests. RESULTS: Group 120 and 400 presented the highest roughness values. For S. epidermidis and S. aureus, Group 1200S presented the lowest values of microbial growth. For E. faecalis at 4 hour, microbial growth was not observed. C. albicans did not adhere to the acrylic resin. Except for Group 1200S, different surface roughnesses did not statistically interfere with microbial adhesion and growth on acrylic surfaces of ocular prostheses. CONCLUSIONS: The roughness did not interfere with the microbial adhesion of the microorganisms evaluated. The use of silica decreases significantly microbial growth.

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This clinical report describes the ocular rehabilitation of a child, initially using an acrylic expander and subsequently the conventional prosthesis. A two-month-old anophthalmic female patient was referred to Araçatuba Dental School, for rehabilitation with ocular prosthesis. The treatment chosen was the manufacturing of expander prostheses changed periodically until the socket reached an adequate size, so that a definitive ocular prosthesis could be installed. The acrylic expander remained in patient's anophthalmic socket for 60 days in order to restore its volume. After this period, ocular prosthesis was installed and replaced according to facial growth. It can be observed that the expander prostheses increased the anophthalmic cavity and provided patient's adaptation for using an ocular prosthesis. The ocular prosthesis set the face aesthetic balance which eventually reflects positively on psychological and social development of the child.

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BACKGROUND: The aim of this systematic review is to evaluate the relationship between two methods used to assess implant stability, investigating whether both provide similar implant stability assessments for the same clinical case. METHODS: A literature search was conducted on MEDLINE-PubMed and Scopus databases, without limitation of the publication period, up to November 2015. The following key words were used, with associations among them: "dental implant," "dental implants," "Osstell," "resonance frequency analysis," "implant stability quotient," "ISQ," "Periotest," "Periotest value," and "PTV." Inclusion criteria were English language, prospective, retrospective, and randomized controlled clinical trials that evaluated implant stability through use of resonance frequency analysis (RFA) and damping capacity analysis (DCA). The study should assess implant stability of only a specific region for all patients or discriminate results evaluated for each region if the analysis had been made in various regions; RFA and DCA should have been applied in the same implants and periods. Studies have been carefully selected, and data of interest were tabulated. RESULTS: Six studies met the inclusion criteria. Although there was significant numerical correlation between values obtained by both methods, data showed that less than half (46%) of cases coincided in relation to implant stability classification. CONCLUSIONS: It can be considered that there is not always a consensus and standardization in the classification of implant stability related to the values obtained by RFA and DCA devices, which could create disagreements and miscommunication among dentistry professionals.

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O controle da formação de biofilme é essencial para manter a saúde da cavidade anoftálmica dos portadores de prótese ocular. As propriedades físicas da resina acrílica, como a sua rugosidade, podem interferir na adesão de microrganismos nas próteses e na formação de biofilmes. Sendo assim, é necessário utilizar soluções de limpeza eficazes e que não causem irritação tecidual na conjuntiva ocular. O objetivo desse trabalho foi verificar a influência da rugosidade de superfície da resina acrílica utilizada na confecção de próteses oculares na formação de biofilme bacteriano, bem como avaliar a eficácia antimicrobiana e citotoxicidade de diferentes soluções para desinfecção de próteses oculares. Para a análise da rugosidade, corpos de prova de resina acrílica foram confeccionados e divididos em 5 grupos de acordo com a granulação de lixa de polimento utilizada: 120, 400, 800, 1200 e 1200S (lixa + sílica). A rugosidade dos corpos de prova foi mensurada por meio de perfilômetro e imagens de Microscopia de Força Atômica foram obtidas para cada grupo. O crescimento das espécies Staphylococcus aureus e Staphylococcus epidermidis sobre os corpos de prova foi avaliado após 4 e 24h, por meio da contagem das Unidades Formadoras de Colônia (UFC)/mL. O efeito dos seguintes tratamentos: soro fisiológico, sabão neutro, clorexidina 4%, pastilhas efervescentes Efferdent®, triclosan 1% e citronela sobre biofilme formado sobre os corpos de prova de resina acrílica também foi avaliado por meio da determinação do número de UFC/mL. A citotoxicidade dos agentes antimicrobianos foi avaliada por meio dos testes de MTT e Neutral Red, após tratamento dos corpos de prova, diariamente, por 1, 7, 15, 30, 60 e 90 dias com as soluções já citadas, sendo avaliados ao fim de cada período. Os dados obtidos foram submetidos à análise estatística adequada, considerando se provinham de dados paramétricos ou não paramétricos. Os resultados demonstraram que os menores valores de rugosidade foram encontrados no grupo 800, 1200 e 1200S. A contagem microbiana foi menor no grupo 1200S e esta diferiu estatisticamente (p>0,05) do controle para ambos os tempos de avaliação e bactérias. Na análise da ação antimicrobiana das soluções para desinfecção, todos os protocolos promoveram redução do crescimento dos microrganismos testados comparados ao controle (crescimento sem a presença do antimicrobiano), sendo que os grupos submetidos ao tratamento com clorexidina 4%, pastilhas efervescentes Efferdent® e triclosan 1% eliminaram o biofilme (p>0,01). Ainda nos ensaios de citotoxicidade, em todos os grupos foi observada proliferação celular das células da conjuntiva acima de 84% (p>0,05). Dessa forma, conclui-se que a rugosidade não interfere significativamente na adesão bacteriana e formação de biofilme, exceto para o grupo 1200S, e que os protocolos de limpeza com imersão em clorexidina 4%, pastilhas efervescentes Efferdent® e triclosan 1% são totalmente eficazes na desinfecção e não apresentam citotoxicidade para com as células da conjuntiva humana, sugerindo sua indicação para desinfecção de próteses oculares(AU)

The control of biofilm formation is essential to maintain the health of anophthalmic cavity of ocular prosthesis wearers. The physical properties of the acrylic resin, such as surface roughness, may interfere with the adhesion of microorganisms to the prostheses. Therefore, it is necessary to use cleaning solutions that are effective and do not cause tissue irritation in ocular conjunctiva. The aim of this study was to verify the influence of surface roughness of the acrylic resin used in the preparation of ocular prosthesis in the formation of bacterial biofilm, as well as to evaluate the antimicrobial efficacy and cytotoxicity of different disinfectants in ocular prostheses. For roughness analysis, acrylic resin samples were prepared and divided into 5 groups according to the granulation of polishing sandpaper used: 120, 400, 800, 1200 and 1200S (sandpaper + silica). The roughness of the samples was measured using a profilometer and Atomic Force Microscopy images were obtained for each group. The microbial growth for Staphylococcus aureus and Staphylococcus epidermidis on the samples was evaluated after 4 and 24 h by counting the Colony Forming Units (CFU)/mL. The effect of the following solutions was also evaluated by CFU/mL: non treated group (immersed in saline solution), neutral soap, 4% chlorhexidine, Efferdent® effervescent tablets, 1% triclosan and citronella. The cytotoxicity of the solutions was evaluated by MTT and Neutral Red after treating the samples daily for 1, 7, 15, 30, 60 and 90 days with the solutions already mentioned, being evaluated at the end of each period. Data were submitted to proper statistical analysis, considering whether data were parametric or non-parametric. The results showed that the lowest roughness values were found in groups 800, 1200 and 1200S. 1200S group also presented the lowest values of microbial growth statistically different from control group (p>0,05), for both periods and bacteria evaluated. In the analysis of the solutions, compared to the control group (microbial growth without the presence of the antimicrobial), all protocols promoted a reduction in the growth of the microorganisms, and the groups submitted to disinfection with 4% chlorhexidine, Efferdent® effervescent tablets and 1% triclosan eliminated the biofilm (p>0,01). In addition, all groups showed cell proliferation of conjunctival cells above 84% in the cytotoxicity assays (p>0,05). Thus, it was concluded that the roughness does not significantly interfere in the adhesion of the microorganisms, except for group 1200S, and that the cleaning protocols with 4% chlorhexidine, Efferdent® effervescent tablets and 1% triclosan are totally effective in the disinfection and do not present cytoxicitiy with human conjunctive cells, what suggests their indication for cleaning of ocular prosthesis(AU)

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The aim of this study was to assess the effect of adding nanoparticles to N1 acrylic resin intended for artificial sclera, in terms of the color stability, microhardness, and flexural strength of the resin. Three hundred samples of N1 acrylic resin were used: 100 samples for color stability and microhardness tests (each test was performed on the opposite side of each sample), and 200 samples for flexural strength testing (100 samples before and after 1,008 hours of accelerated aging). Samples for each test were separated into ten groups (n=10), ie, without nanoparticles (control group) or with nanoparticles of zinc oxide, titanium dioxide (TiO2), and barium sulfate at weight concentrations of 1%, 2%, and 2.5% (nanoparticle groups). Data were subjected to statistical analysis with nested analysis of variance and Tukey's test (P<0.05 significance level). Among the nanoparticle groups, the TiO2 groups showed better color stability at all concentrations. Microhardness values increased after artificial aging, except for the control and zinc oxide groups. After aging, the 1%-2% TiO2 groups had significantly higher microhardness values compared with the other nanoparticle groups. Before aging, there was a significant difference in flexural strength between the control and nanoparticle groups. After aging, the control and TiO2 groups, regardless of concentration, showed the lowest flexural strength values. Incorporation of nanoparticles directly influenced the acrylic resin properties, with TiO2 being the most influential nanoparticle in terms of the evaluated properties.

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The aim of this study was to evaluate the effect of thermocycling and immersion in mouthwash or beverage solutions on the color stability of four different acrylic resin-based dentures (Onda Cryl, OC; QC20, QC; Classico, CL; and Lucitone, LU). The factors evaluated were type of acrylic resin, immersion time, and solution (mouthwash or beverage). A total of 224 denture samples were fabricated. For each type of resin, eight samples were immersed in mouthwashes (Plax-Colgate, PC; Listerine, LI; and Oral-B, OB), beverages (coffee, CP; cola, C; and wine, W), and artificial saliva (AS; control). The color change (DE) was evaluated before (baseline) and after thermocycling (T1), and after immersion in solution for 1 h (T2), 3 h (T3), 24 h (T4), 48 h (T5), and 96 h (T6). The CIE Lab system was used to determine the color changes. The thermocycling test was performed for 5000 cycles. Data were submitted to three-way repeated-measures analysis of variance and Tukey's test (p<0.05). When the samples were immersed in each mouthwash, all assessed factors, associated or not, significantly influenced the color change values, except there was no association between the mouthwash and acrylic resin. Similarly, when the samples were immersed in each beverage, all studied factors influenced the color change values. In general, regardless of the solution, LU exhibited the greatest DE values in the period from T1 to T5; and QC presented the greatest DE values at T6. Thus, thermocycling and immersion in the various solutions influenced the color stability of acrylic resins and QC showed the greatest color alteration.

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Os abutments de zircônia são utilizados para obter resultados estéticos satisfatórios em reabilitações anteriores de próteses sobre implantes quando os componentes de titânio causam coloração acinzentada na gengiva peri-implantar. Contudo, a literatura não possui um consenso no que diz respeito a estabilidade deste tecido em contato com abutments de zircônia. Dessa forma, o objetivo do presente estudo foi relatar o caso de uma paciente reabilitada com uma coroa cerâmica implanto-retida sobre abutment de zircônia, após 3 anos de acompanhamento. Paciente do sexo feminino de 47 anos de idade foi admitida na clínica odontológica da Faculdade de Odontologia de Araçatuba queixando-se de uma fratura em sua coroa unitária implanto-retida na região do elemento 22. A mesma optou pela troca da prótese que apresentava fratura por outra total cerâmica. Após 3 anos de acompanhamento, pode-se observar a manutenção do resultado estético e a estabilidade do tecido mole periimplantar, sem a presença de inflamações ou recessão. Dentro das limitações de um relato de caso, conclui-se que a utilização de abutment de zircônia é uma maneira eficaz de reabilitação, preservando a estética e a função através da manutenção dos tecidos

Zirconia abutments are used to obtain satisfactory aesthetic results in implant fixed anterior prostheses when metal abutments promote a grayish mucosal discoloration of the peri-implant soft tissues. However, there is a lack of studies to confirm the clinical performance of the peri-implant soft tissues surrouding zirconia abutments. This study described a case report of a patient treated with implant fixed all-ceramic crown made out on zirconia abutment after 3 years of followup. A 47-year-old female patient was admitted to the dental clinic (Aracatuba Dental School) complaining about the fracture of her implant fixed single crown in the region of the left lateral incisor. The patient chose the replacement of the fractured prosthesis for an allceramic crown. After 3 years of follow-up it was observed that maintenance of the aesthetic results and the peri-implant soft tissue without any inflammation or gingival recessions. Within the limitations of a case report, it can be conclude that zirconia abutments is a effective rehabilitation treatment because it preserves the aesthetics and function through the maintenance of peri-implant tissues

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