RESUMO Dada sua versatilidade e excelência estética, a resina composta é o material restaurador direto mais utilizado nas intervenções da clínica odontológica. Uso tão intenso levou pesquisadores e fabricantes a trabalharem na evolução deste material, conferindo-lhe aumento em sua resistência à compressão e abrasão, bem como melhora em seu comportamento estético. Infelizmente, um problema intrínseco da resina, a contração de polimerização é sua principal desvantagem, e caracteriza-se pela alteração volumétrica que sofre quando as moléculas de seus monômeros se unem para a formação das cadeias poliméricas. Uma das principais técnicas para combater os efeitos nocivos desta alteração volumétrica é a inserção incremental do material na cavidade a ser restaurada. Nesta pesquisa, a contração de polimerização de uma resina composta de uso universal (Charisma Heraeus Kullser) será avaliada variando-se a técnica de inserção do material na cavidade em incremento único ou três incrementos oblíquos, através do método da picnometria a gás. O picnômetro Accupyc 1330 (Micromeritics) permite medições rápidas e fiéis do volume da resina composta antes e após a fotoativação. Os resultados mostram que ocorreram diferenças estatísticas entre as duas técnicas, sendo a técnica de único incremento a que apresentou menor contração de polimerização. / Because of its versatility and aestetic excellency, composite resin is one of the most utilized direct restorative materials. Because of the resin intense use, the number of researches to improve its performance are numerous, and can be verified by the resin aestethetic behavior and its compressive and abrasion strenght increase. In spite of the mentioned developments, the polymerization shrinkage inherent of the material had been a major deficiency, and can be understood by the alteration in volume of the material after the polymerization process. In the present study, the polymerization shrinkage of the restorative material Charisma (Heraes Kulzer), was evaluated using bulk and incremental placement techniques and measured by gas pycnometer. Accupyc 1330 (Micromeritics, USA) pycnometer measures the helium displacement with great precision, allowing fast and accurate measurements of the volume of the composite resin before and after polymerization, without interference of the moisture or temperature. The results showed statistically significant diferences between the two placement techniques, with the bulk technique showing lower polymerization shrinkage than the incremental technique.

RESUMO Dada sua versatilidade e excelência estética, a resina composta é o material restaurador direto mais utilizado nas intervenções da clínica odontológica. Uso tão intenso levou pesquisadores e fabricantes a trabalharem na evolução deste material, conferindo-lhe aumento em sua resistência à compressão e abrasão, bem como melhora em seu comportamento estético. Infelizmente, um problema intrínseco da resina, a contração de polimerização é sua principal desvantagem, e caracteriza-se pela alteração volumétrica que sofre quando as moléculas de seus monômeros se unem para a formação das cadeias poliméricas. Uma das principais técnicas para combater os efeitos nocivos desta alteração volumétrica é a inserção incremental do material na cavidade a ser restaurada. Nesta pesquisa, a contração de polimerização de uma resina composta de uso universal (Charisma Heraeus Kullser) será avaliada variando-se a técnica de inserção do material na cavidade em incremento único ou três incrementos oblíquos, através do método da picnometria a gás. O picnômetro Accupyc 1330 (Micromeritics) permite medições rápidas e fiéis do volume da resina composta antes e após a fotoativação. Os resultados mostram que ocorreram diferenças estatísticas entre as duas técnicas, sendo a técnica de único incremento a que apresentou menor contração de polimerização. / Because of its versatility and aestetic excellency, composite resin is one of the most utilized direct restorative materials. Because of the resin intense use, the number of researches to improve its performance are numerous, and can be verified by the resin aestethetic behavior and its compressive and abrasion strenght increase. In spite of the mentioned developments, the polymerization shrinkage inherent of the material had been a major deficiency, and can be understood by the alteration in volume of the material after the polymerization process. In the present study, the polymerization shrinkage of the restorative material Charisma (Heraes Kulzer), was evaluated using bulk and incremental placement techniques and measured by gas pycnometer. Accupyc 1330 (Micromeritics, USA) pycnometer measures the helium displacement with great precision, allowing fast and accurate measurements of the volume of the composite resin before and after polymerization, without interference of the moisture or temperature. The results showed statistically significant diferences between the two placement techniques, with the bulk technique showing lower polymerization shrinkage than the incremental technique.

Concrete is the most widely used man-made material in the world. Its versatility, strength, and relative ease of construction allow it to be used in the majority of civil infrastructure. However, concrete production plays a significant role in greenhouse gas emissions, accounting for around 8% of CO2 emissions worldwide. This thesis aims to reduce the demand for cement in concrete construction, thus reducing the carbon footprint of the concrete, by focusing on classifying and determining the effectiveness of seven different quarry by-products as partial replacements of cement. Several methods were utilized in this study to characterize the quarry by-products: particle size distribution, helium pycnometry, X-Ray diffraction, X-Ray fluorescence, scanning electron microscopy, and a modified ASTM C1897 Method A that utilizes isothermal calorimetry and thermogravimetric analysis. These various methods allowed for the determination of the physical properties (e.g., gradation, specific gravity, and morphology) and the chemical properties (e.g., mineralogy and reactivity in a cementitious system). The quarry by-products were classified as four granites, two limestones, and one greenstone. These quarry by-products were found to be non-pozzolanic and non-hydraulic. However, there are indications that there may be reactions with the various clays and feldspars in the quarry by-products with calcium hydroxide, which suggests a degree of reactivity that is not necessarily pozzolanic or hydraulic. / Master of Science / Concrete is the most widely used man-made material in the world. Its versatility, strength, and relative ease of construction allow it to be used in the majority of civil infrastructure. However, concrete production plays a significant role in greenhouse gas emissions, accounting for around 8% of CO2 emissions worldwide. This thesis aims to reduce the demand for cement in concrete construction, thus reducing the carbon footprint of the concrete, by focusing on classifying and determining the effectiveness of seven different quarry by-products as partial replacements of cement. Several methods were utilized in this study to determine the physical properties (e.g., gradation, specific gravity, and morphology) and the chemical properties (e.g., mineralogy and reactivity in a cementitious solution) of the materials. The quarry by-products were classified as four granites, two limestones, and one greenstone. In general, these quarry by-products were not found to be reactive as a supplementary cementitious material, although the data may suggest some degree of reactivity between calcium hydroxide and the clays and/or feldspars in the quarry by-products.