ABSTRACT
O objetivo do presente estudo foi comparar as características superficiais de amostras de Titânio (Ti) porosas (Ti-P) e de Ti Denso (Ti-D), usando MEV e rugosímetro 3D. O experimento foi realizado em triplicata (n= 3). Inicialmente foram obtidas imagens em MEV de alta definição das superfícies. Na sequência, as amostras eram analisadas em rugosímetro 3D utilizando parâmetros de amplitude (Sa e St) que indicam a rugosidade média, um parâmetro espacial (Str), que indica a uniformidade da textura, e um parâmetro híbrido (Sdr) que indica a área superficial disponível. Fotomicrografias mostraram que o Ti-P apresentava poros abertos e amplos. Além disso, nesta superfície foram observados valores de Sa e de St bastante altos (35.3 ± 1.20 μm e 315.67 ± 14.36 μm, respectivamente), valor de Str de 0.81 ± 0.08 (tendendo a 1, ou seja, isotrópico) e de Sdr de 42.57% ± 0.67, enquanto o Ti-D apresentava uma superfície lisa e valores de rugosidade bastante baixos (Sa e St de 0.17 ± 0.04 e de 5.31 ± 0.49, respectivamente), Str de 0.00 ± 0.00 (anisotrópico) e Sdr de apenas 0.14% ± 0.04. Portanto, pode-se concluir que as superfícies de Ti poroso apresentaram características topográficas bastante distintas do Ti Denso, como poros abertos e amplos, maior rugosidade, isotropia e maior área superficial disponível.
The aim of this study was to compare surface topographical features of porous Ti (Ti-P) and Dense Ti (Ti-D) samples, using SEM and 3D perfilometer. The study was performed in triplicate (n = 3). First, SEM high-definition images of both surfaces were obtained. Then, the samples were analysed by 3D perfilometer, using amplitude parameters (Sa and St), a Spatial parameter (Str) and a Hybrid parameter (Sdr). Open and wide pores were observed on Ti-P surface by photomicrographs. Furthermore, Ti-P showed higher values of amplitude roughness (Sa and St values of 35.3 ± 1.20 μm and 315.67 ± 14.36 μm, respectively), higher Str value (0.81± 0.08, tending to 1, i.e, isotropic) and Sdr value of 42.57% ± 0.67. On the other hand, Ti-D presented a smooth surface and very low roughness values (Sa and St, 0.17 ± 0.04 and 5.31 ± 0.49, respectively), Str 0.00 ± 0.00 (anisotropic) and Sdr 0.14% ± 0.04. So, it can be concluded that Ti-P andTi-D surfaces presented very distinct topographic features, especially open and wide pores, higher roughness, isotropy and higher available surface area.
Subject(s)
Metallurgy , Titanium , TopographyABSTRACT
Este artigo avalia o desempenho do compósito restaurador à base de silorano na interface de restaurações adesivas. Cavidades cilíndricas classe I (Ø=5,0mm e h=2,0mm) (fator-C=2,6) foram preparadas em dez molares humanos. Os compósitos avaliados foram Fitek P60 (P) e Filtek LS (LS). As cavidades foram restauradas em incremento único com P e LS, utilizando-se o protocolo de fotoativação convencional: 850mW/cm2/25s. As restaurações foram seccionadas e analisadas em escâner tridimensional, e os danos foram submetidos ao tratamento estatístico. Foi detectada diferença entre os grupos estudados PxLS (α=0,001). Verificou-se presença de fendas marginais na região dos ângulos internos de todos os corpos de prova em que foi utilizado P, e somente 20% quando foi utilizado LS. Conclui-se que LS produziu formação reduzida de fendas em comparação com P.
To evaluate silorane-bases restorative composite performance on marginal integrity of adhesive restorations interface. Cylindrical class I cavities (Ø=5.0mm and h=2.0mm) (C-factor=2.6) were prepared using ten human molars with a diamond bur # 4054. Two minifilled hybrid composites with different type of organic matrixes were evaluated: methacrylate-based [Fitek P60 (P)] and silorane-based [Filtek LS (LS)]. The cavities were restored in bulk with P and LS using the light-curing mode Standard - 850mW/cm2/25s (±21 J/cm2). After storage, finishing and polishing, the restorations were cut into two slices and analyzed in three-dimensional scanner. Data obtained were submitted to Kruskal-Wallis non-parametric test (α=0.01). It was detected significant statistical difference between studies groups PxLS (α=0.001).It was verified the presence on internal angles region of all specimens in which were restored with P of gap formation and only 20% in which were restored with LS. It was possible to conclude LS produced lower gap formation in comparison with P.
Subject(s)
Composite Resins , Dental Restoration, Permanent , Polymethacrylic Acids , Silorane ResinsABSTRACT
OBJECTIVE: The aim of this study was to evaluate the effect of C-factor and light-curing protocol on gap formation in composite resin restorations. Material and METHODS: Cylindrical cavities with 5.0 mm diameter and three different depths (A=1.0, B=2.0 and C=3.0 mm) were prepared on the occlusal surface of 30 human molars and restored in a single increment with P 60. The composite resin was light-cured according to two protocols: standard - 850 mW/cm² / 20 s and gradual - 100 up to 1000 mW/cm² / 10 s + 1000 mW/cm² / 10 s. After storage in distilled water (37°C/7 days), the restorations were cut into three slices in a buccolingual direction and the gap widths were analyzed using a 3D-scanning system. The data were submitted to ANOVA and Student-Newman-Keuls test (alpha=0.05). RESULTS: ANOVA detected a significant influence for the C-factor and light-curing protocol as independent factors, and for the double interaction C-factor vs. light-curing protocol. Cavities with higher C-factor presented the highest gap formation. The gradual light-curing protocol led to smaller gap formation at cavity interfaces. CONCLUSIONS: The findings of this study suggest that the C-factor played an essential role in gap formation. The gradual light-curing protocol may allow relaxation of composite resin restoration during polymerization reaction.