Levantamento do assoalho do seio maxilar – aspectos clínicos e de imagem / Maxillary sinus floor lifting – clinical and imaging aspects

Este artigo demonstra os recursos de imagens que contribuem para um diagnóstico e planejamento eficazes na execução previsível do procedimento cirúrgico de levantamento de assoalho de seio maxilar (ESM), um problema comumente encontrado na reabilitação posterior de maxila, limitando a instalação de implantes de comprimento médio (10 mm). Os procedimentos de elevação do assoalho do seio maxilar (ESM) são uma opção para a resolução desse problema. Atualmente, duas principais técnicas são utilizadas para ESM: a técnica atraumática, com a utilização de osteótomos e instalação simultânea de implantes; e a técnica de janela lateral, com ou sem instalação simultânea de implantes. A decisão da técnica a ser realizada é baseada na avaliação da quantidade óssea e na possibilidade de estabilidade primária dos implantes. Esse passo é realizado com o auxílio de exames de imagens bi e tridimensionais. Nos casos em que é necessária a utilização de enxertos, o osso autógeno é considerado o padrão-ouro. No entanto, a literatura também apresenta casos de sucesso utilizando substitutos ósseos e combinações com osso autógeno. Apesar da técnica já estar bem desenvolvida, algumas complicações podem ocorrer em procedimentos de ESM, como a perfuração da membrana sinusal, hemorragias, estabilidade primária do implante insuficiente, deslocamento do enxerto dentro do seio maxilar e exposição ou lesões de nervos...

This article highlights the imaging resources contributing to effective diagnosis and planning for elevation of the maxillary sinus floor (ESM), a common issue at the posterior region which prevents implant placement of 10 mm in length. ESM procedures can overcome this situation. Nowadays, two main techniques are available for ESM: the atraumatic technique, with the use of osteotomes and immediate implant placement, and the lateral window technique, with/without implant placement. Decisions are based on available bone quantity and primary implant stability. Also, bi- and three-dimensional imaging techniques are valuable tool in this process. When necessary, the autogenous bone is still the gold standard. However, there are reports of success with bone substitutes and combinations with autogenous material. Although well-developed, some complications occur with ESM procedures, as well as membrane perforation, hemorrhage, lack of primary implant stability, and graft displacement inside the maxillary sinus, exposure, and nerve damage...

Effect of fluoride solutions on color and surface roughness of dental composites / Efeito de soluções fluoretadas sobre a cor e rugosidade de superfície de compósitos odontológicos

Objective: The aim of this study was to assess the ac-tion of fluoride solutions on color stability (?E) and sur-face roughness (Ra) of composites (HeliomolarTM, 4 Sea-sonsTM, Tetric N-CeramTM, SR AdoroTM). Materials and method: A Teflon matrix (12x2 mm) was used to fabri-cate 24 test specimens for each composite. The samples were separated into 4 groups (n=6), according to the immersion solution: distilled water (control), acidulated phosphate fluoride (1.23%), neutral sodium fluoride gel (2%), and solution of sodium fluoride (0.05%). Color (Spectrophotometer PCB 6807) and roughness (Surf-corder SE 1700) readings were performed before and after immersion into the solutions. Results: Composites presented color alteration within clinically acceptable limits (?E<3.3), increasing according to the periods of immersion. Regarding roughness, it was observed that Ra values were lower than the critical limit to promote increase in dental biofilm retention (Ra>0.2 µm). Con-clusions: Color and surface roughness alteration of the different composites was clinically acceptable after im-mersion in all fluoride solutions and in all periods.

Effect of staining solutions and repolishing on color stability of direct composites

OBJECTIVES: The purpose of this study was to assess the color change of three types of composite resins exposed to coffee and cola drink, and the effect of repolishing on the color stability of these composites after staining. MATERIALS AND METHODS: Fifteen specimens (15 mm diameter and 2 mm thick) were fabricated from microhybrid (Esthet-X; Dentsply and Filtek Z-250; 3M ESPE) and high-density hybrid (Surefil; Dentsply) composites, and were finished and polished with aluminum oxide discs (Sof-Lex; 3M ESPE). Color of the specimens was measured according to the CIE L*a*b* system in a refection spectrophotometer (PCB 6807; BYK Gardner). After baseline color measurements, 5 specimens of each resin were immersed in different staining solutions for 15 days: G1 - distilled water (control), G2 - coffee, G3 - cola soft drink. Afterwards, new color measurement was performed and the specimens were repolished and submitted to new color reading. Color stability was determined by the difference (ΔE) between the coordinates L*, a*, and b* obtained from the specimens before and after immersion into the solutions and after repolishing. RESULTS: There was no statistically signifcant difference (ANOVA, Tukey's test; p>0.05) among the ΔE values for the different types of composites after staining or repolishing. For all composite resins, coffee promoted more color change (ΔE>3.3) than distilled water and the cola soft drink. After repolishing, the ΔE values of the specimens immersed in coffee decreased to clinically acceptable values (ΔE<3.3), but remained signifcantly higher than those of the other groups. CONCLUSIONS: No signifcant difference was found among composite resins or between color values before and after repolishing of specimens immersed in distilled water and cola. Immersing specimens in coffee caused greater color change in all types of composite resins tested in this study and repolishing contributed to decrease staining to clinically acceptable ΔE values.

Análise das propriedades físico-mecânicas e biológicas dos cimentos resinosos / Analysis of the physical-mechanical and biological properties of the resinous cements

A procura cada vez maior por tratamentos restauradores estéticos e a eficiência de união entre o dente e o material restaurador proporcionam o desenvolvimento de inúmeras marcas comerciais de cimentos resinosos. O objetivo deste estudo foi realizar uma análise crítica sobre as propriedades físico-mecânicas e biológicas de diversos sistemas de cimentos resinosos, comparando-os entre si e também com os outros sistemas de cimentos não-resinosos; com intuito de auxiliar os profissionais da Odontologia na correta seleção e indicação desses cimentos, o que poderá contribuir para um maior sucesso do tratamento protético.