Drill material and design, number of uses, depth and drilling load applied appear to influence bone temperature variations during implant site preparation. Drilling depth was a predominant factor in bone temperature increase. Both drills can be used up to 50 times without producing harmful temperatures to bone tissue or severe signs of wear and deformation.

ResumoEste trabalho teve por objetivo avaliar a influência do tratamento químico da borra de café em relação as propriedades mecânicas e térmicas, morfologia e suscetibilidade à biodegradação quando utilizada na preparação de compósitos com Poli(ε-caprolactona) comparando-o com o polímero puro. A borra de café foi submetida ao tratamento álcali com hidróxido de sódio, seguida da acetilação. Os compósitos foram preparados utilizando diferentes porcentagens de borra de café. Com tratamento químico houve um aumento na estabilidade térmica da borra de café. Houve um aumento significativo no módulo elástico para o compósito com 10% de borra de café acetilada. As imagens obtidas por MEV mostraram uma parcial interação fibra/matriz para compósitos com borra acetilada. As análises térmicas mostraram que a adição de borra de café deslocou positivamente 10º C o pico máximo de degradação térmica em relação ao polímero puro. As amostras mais suscetíveis à biodegradação foram as que continham borra de café acetilada. Palavras-chave: compósito polimérico, borra de café, poliéster biodegradável. AbstractThis study aimed to evaluate the influence of chemical treatments of coffee grounds in relation to mechanical, thermal and morphological properties, and its susceptibility to biodegradation when used in the preparation of composites with poly (ε-caprolactone) as compared to pure polymer. The coffee grounds were submitted to alkali treatment with sodium hydroxide followed by acetylation. The composites were prepared using different percentages of coffee grounds. There was an increase in the thermal stability of coffee grounds using chemical treatment, and a significant increase of the elastic modulus for the composite with 10% acetylated coffee grounds. The images obtained by SEM showed a partial interaction between fiber/matrix for composites and acetylated coffee grounds. The Thermal analysis showed that the addition of coffee grounds positively shifted 10°C, the maximum peak of thermal degradation, as compared to pure polymer. The most susceptible samples to biodegradation were those that contained acetylated coffee grounds.