Abstract Currently, there is no consensus on the indications and clinical performance of implant-supported overdentures (IODs) involving computer-aided design and manufacturing (CAD-CAM) bars. Objective: To evaluate the performance of IODs involving CAD-CAM bars. Methodology: A comprehensive search of studies published until May 2023 was conducted in many databases, including PubMed/MEDLINE, Web of Science, Cochrane Library, and SciELO, following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA). The population, intervention, comparison, outcome (PICO) question was: “How do IODs retained by bars fabricated by CAD-CAM technology perform in daily clinical practice?” The meta-analysis included clinical studies based on effect size and a two-tailed null test with a 95% confidence interval (CI). Results: Ten studies were included in the meta-analysis. Among them, nine reported a 100% implant survival rate for all CAD-CAM milled bars. Complications were reported in two studies with CAD/CAM-milled titanium bars, and one study reported more fractures in soldered gold bars used in maxillary rehabilitation. However, no fractures were observed in IODs retained by PEEK and zirconia bars. According to six studies, biological complications, including peri-implantitis, were minimal in the BioHPP and PEEK bar groups, while no cases were reported in the titanium or zirconia bar groups. CAD-CAM-milled zirconia bars had higher plaque and bleeding indices compared with titanium bars, as evidenced by findings from five studies. All four studies that evaluated Oral Health Impact Profile (OHIP) scores showed a positive effect of IODs retained by CAD-CAM milled titanium bars on quality of life. Patient satisfaction and acceptance by prosthodontists were significantly high, according to the results of five studies. Conclusion: Overdentures retained with CAD-CAM milled titanium bars show great potential for use in daily clinical practice. Moreover, patient and practitioner satisfaction was very high when this method was used.

RESUMO Objetivo As próteses metalocerâmicas apresentam altas taxas de sobrevivência e, por isso, são indicadas para diversos casos em reabilitação oral. Entretanto, na literatura científica, existem poucos relatos clínicos sobre os fatores que levam à fratura dessas restaurações. Diante do exposto, o presente estudo teve como objetivo avaliar se a quantidade de elementos que compõem a prótese, se a quantidade de elementos por retentor, se o tipo de prótese e tipo de pilar, bem como sua localização, e o bruxismo, influenciam ou não nas fraturas dessas restaurações indiretas. Métodos Para isso, selecionaram-se 74 próteses metalocerâmicas, instaladas entre 2000 e 2010 em 16 pacientes, com acompanhamento mínimo de quatro anos. Foram coletadas informações dos pacientes, como: gênero, idade, data da instalação das próteses e cerâmica utilizada. Durante a avaliação clínica, observou-se a integridade da prótese e, em caso de fratura, coletava-se informações sobre a história clínica. As características do dente antagonista também foram avaliadas. Além disso, aplicou-se um questionário, com o intuito de identificar a provável presença de bruxismo. Resultados Como resultado, tem-se que a taxa de sucesso das próteses metalocerâmicas foi de 87,8% e, a taxa de sobrevivência, foi de 89,1%. A taxa de sucesso não teve influência da idade, tempo de instalação, número de próteses na boca, número de elementos ou pilares. Conclusão Embora pouco frequente, a fratura da cerâmica de cobertura foi a complicação mais comum. As próteses metalocerâmicas possuem altas taxas de sobrevida e de sucesso, o que garante a longevidade e a indicação desse tipo de restauração.

ABSTRACT Objective Metal-ceramic prosthesis are the treatment of choice in oral rehabilitation because of their high survival rates. However, there are few reports in the scientific literature about factors that lead to fractures of metal-ceramic prostheses. The aim of this study was to evaluate whether prostheses units number, abutment type and number, type of the prostheses, prostheses position in the mouth, bruxism and occlusal plaque influence the incidence of fractures in fixed metal-ceramic prostheses. Methods For this study, 16 patients were selected, totaling 74 metal-ceramic prostheses installed between 2000-2010, with follow up of at least four years. Besides dental history, other information was collected, such as patients’ gender and age, prostheses installation date, and the ceramic system used. In case of prostheses fracture, a questionnaire was applied to identify signs of bruxism. A clinical evaluation was done to evaluate the prostheses integrity and opposing dentition characteristics. Success, failure and survival rates were determined. Results The results showed that the success rate of metal-ceramic prostheses was 87.8% and the survival rate was 89.1%. In addition, the success rate was independent of patient age, prostheses installation time, number of prosthesis, number of prosthesis’ units and abutments. The qualitative variables also did not show significant statistical results between success and failure rates. Conclusion It was concluded that metal-ceramic prostheses have high success and survival rates, what guarantees longevity and indication of this type of prostheses in daily practice.

Resumo O objetivo deste estudo foi verificar se as modificações feitas com o adesivo etil cianoacrilato, ECA (Super Bonder ®, Loctite, Itapevi, SP, Brasil) sobre as resinas acrílicas para reembasamento, poderiam inibir ou reduzir a formação de biofilmes de C.albicans sobre sua superfície quando comparado com um selante de superfície comercial (BisCover®, Bisco, Schaumburg, EUA). Amostras de resina acrílica para reembasamento foram fabricadas e divididas aleatoriamente em 6 grupos (n=8): CG (grupo controle), sem tratamento superficial; ECA1, revestimento de ECA na superfície antes da esterilização; ECA2, revestimento de ECA após esterilização; ECA3, ECA incorporado no volume da resina; DPE1, revestimento de BisCover® antes da esterilização; DPE2, revestimento de BisCover® após esterilização. Os espécimes foram inoculados com C. albicans SC5314 (1x107 células/mL) e incubados durante 24 h. Seguidamente, o biofilme foi corado com LIVE/DEAD® BaclightTM L7007 Kit e analisado no microscópio confocal de varredura a laser. As imagens foram avaliadas pelo software bioImageL® v.2.0, no qual foram calculados o biovolume total (μm3), as células viáveis (%) e a área coberta (%). Os dados foram analisados estatisticamente pelos testes de Kruskal-Wallis e Dunn (p<0,05). Os resultados mostraram que os grupos revestidos com ECA apresentaram os melhores resultados, reduzindo a formação do biofilme de C. albicans. As imagens adquiridas revelaram que esses grupos (ECA1 e ECA2) apresentaram um número reduzido de células, principalmente na forma de levedura (menos patogênico), enquanto os outros grupos apresentaram um maior número de células, principalmente na forma de hifas (mais patogênicas). Com base nessas descobertas, encontra-se um efeito benéfico na aplicação do adesivo ECA sobre as superfícies das resinas acrílicas para reembasamento, sugerindo assim uma nova alternativa de prevenir a formação de biofilme fúngico em próteses dentárias.

Abstract The aim of this study was to verify whether modifications made in a hard chairside reline resin by an ethyl-cyanoacrylate adhesive, ECA (Super Bonder®, Loctite, Itapevi, SP, Brazil) would be able to inhibit or reduce Candida albicans biofilm formation on its surface, comparing to a commercial surface sealant (BisCover®, Bisco, Schaumburg, USA). Reline resin specimens were fabricated and randomly divided into 6 groups (n=8): CG (control group), no surface treatment; ECA1, ECA coating on the surface before sterilization; ECA2, ECA coating after sterilization; ECA3, ECA incorporated in the resin bulk; DPE1, BisCover® coating before sterilization; DPE2, BisCover® coating after sterilization. Specimens were inoculated with C. albicans SC5314 (1x107 cells/mL) and incubated for 24 h. Then, the biofilm were stained with LIVE/DEAD® BaclightTM L7007 Kit and analyzed by Confocal Laser Scanning Microscopy. The images were evaluated by bioImageL® v.2.0 software and total biovolume (µm3), viable cells (%), and covered area (%) were calculated. Data were statistically analyzed by Kruskal-Wallis and Dunn tests (p<0.05). Results showed that ECA-coated groups presented better results, reducing C. albicans biofilm formation. Acquired images revealed that these groups (ECA1 and ECA2) presented a reduced number of cells, mostly in yeast form (less pathogenic), while the other groups presented higher number of cells, mostly in hyphae form (more pathogenic). Based on these findings, a beneficial effect of Super Bonder® coating reline resins surface could be demonstrated, suggesting a promising way to prevent fungal biofilm formation on dentures.

Resumo Avaliar a adição de antifúngicos nas mínimas concentrações inibitórias (MCIs) para o biofilme de Candida albicans sobre a dureza e rugosidade da reembasadores resilientes temporários. Foram confeccionados corpos de prova (n=8; 36×7×6 mm) a partir de um condicionador de tecido (Softone) e um reembasador resiliente (Trusoft), sem (controle) ou com a incorporação de fármacos nas MCIs: nistatina (0,032 g/mL), diacetato de clorexidina (0,064 g/mL), cetoconazol (0,128 g/mL), miconazol (0,256 g/mL) e itraconazol (0,256 g/mL). Os corpos de prova foram armazenados em água destilada a 37 °C durante 24 h, 7 dias e 14 dias antes das mensurações de dureza e rugosidade. Os dados foram analisados por ANOVA 3-fatores e teste de Tukey HSD (α=0,05). A adição dos antifúngicos em ambos os materiais não demonstrou nenhuma alteração evidente na dureza ou diminuiu esta propriedade em comparação com o controle, exceto para o miconazol no Softone que aumentou a dureza após 14 dias (p=0,003). A adição de nistatina aos dois materiais, clorexidina no Trusoft e cetoconazol no Softone não resultou em alterações significativas de rugosidade em comparação com o controle após 7 e 14 dias (p>0,05). Nestes períodos, o itraconazol aumentou a rugosidade de ambos os materiais (p<0,001). A adição de todos os antifúngicos, exceto para o miconazol no Softone, não resultou em efeitos deletérios sobre a dureza dos materiais ao longo do tempo de avaliação. As MCIs de nistatina em ambos os materiais reembasadores resilientes temporários, cetoconazol no Softone e clorexidina no Trusoft não produziram efeitos deletérios para a rugosidade em até 14 dias.

Abstract Evaluating the addition of minimum inhibitory concentrations (MICs) of antifungals for Candida albicans biofilm on the hardness and roughness of temporary denture soft liners. Specimens (n=8; 36×7×6 mm) of tissue conditioner (Softone) and resilient liner (Trusoft) were produced either without (control) or with incorporation of drugs at MICs: nystatin (0.032 g/mL), chlorhexidine diacetate (0.064 g/mL), ketoconazole (0.128 g/mL), miconazole (0.256 g/mL) and itraconazole (0.256 g/mL). Specimens were stored in distilled water at 37 °C for 24 h, 7 days and 14 days prior to the hardness/roughness measurements. Data were analyzed by 3-way ANOVA and Tukey HSD test (α=0.05). The addition of the antifungals into both materials demonstrated no evident hardness change or decrease of this property compared with the control, except for miconazole in Softone, which increased the hardness after 14 days (p=0.003). The addition of nystatin into both materials, chlorhexidine in Trusoft and ketoconazole in Softone resulted in no significant changes of roughness compared with the control, after 7 days and 14 days (p>0.05). In these periods, itraconazole increased the roughness of both materials (p<0.001). The addition of all antifungals, except for the miconazole in Softone, resulted in no deleterious effects on the materials’ hardness over the evaluation time. The MICs of nystatin in both temporary soft lining materials, ketoconazole in Softone and chlorhexidine in Trusoft resulted in no deleterious effects for roughness up to 14 days.

OBJECTIVE: Chemical solutions have been widely used for disinfection of dentures, but their effect on color stability of denture tooth acrylic resins after repeated procedures is still unclear. The aim of this in vitro study was to evaluate whether repeated cycles of chemical disinfectants affected the color stability of two denture tooth acrylic resins. MATERIAL AND METHODS: Sixty disc-shaped specimens (40 mm x 3 mm) were fabricated from two different brands (Artiplus and Trilux) of denture tooth acrylic resin. The specimens from each brand (n=30) were randomly divided into 6 groups (n=5) and immersed in the following solutions: distilled water (control group) and 5 disinfecting solutions (1% sodium hypochlorite, 2% sodium hypochlorite, 5.25% sodium hypochlorite, 2% glutaraldehyde, and 4% chlorhexidine gluconate). Tooth color measurements were made by spectrophotometry. Before disinfection, the initial color of each tooth was recorded. Further color measurements were determined after subjecting the specimens to 7, 21, 30, 45, 60, and 90 immersion cycles in each tested solution. Color differences (ΔE*) were determined using the CIE L*a*b* color system. Data were analyzed using two-way repeated measures analysis of variance (ANOVA) followed by Tukey tests. The significance level was set at 5%. RESULTS: There were statistically significant differences in ΔE* among the 5 disinfectants and water during the 90 cycles of immersion for both denture tooth acrylic resins. Distilled water promoted the greatest color change in both denture tooth acrylic resins, nevertheless none of tested disinfectants promoted ΔE* values higher than 1.0 on these acrylic materials during the 90 cycles of disinfection. CONCLUSIONS: Repeated immersion cycles in disinfecting solutions alter ΔE* values, however these values do not compromise the color of the tested denture tooth acrylic resins because they are imperceptible to the human eye.