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The main goal of this work is to study the influence on mechanical bone behaviour using different thread profiles shapes considered in titanium dental implants. The biomechanical behaviour of bone and thread implant profile play an important role on the study of stresses and strains at bone-implant interface. The success of dental surgeries depends on the mechanical stimulus (stress, strain, strain rate, strain energy, density…) between the bone and the implant. In this work, four different threads profiles shapes were considered (Model 1 - Plateau typeA, Model 2 - Plateau typeB, Model 3 - Triangular, Model 4 - Rectangular) and for each one two internal diameters equal to 4 and 6mm. The results about the chosen thread profile shape and the diameter give additional information about the transferred stresses between bone-implant to guarantee the stability of the implant and sustain loads during or after osseointegration.

Oxidative stress and mitochondrial dysfunction have been associated with the age-related decline of oocyte quality and strategies for their prevention are currently quested. Urolithin A (UA) is a natural metabolite with pro-apoptotic and antioxidant effects, capable of preventing the accumulation of dysfunctional mitochondria in different aged cells. UA has never been tested in bovine oocytes. Our aim was to study the effect of UA on the developmental potential of cumulus-oocyte-complexes (COCs) and granulosa cells’ (GCs) expression of important genes related to reproductive competence. Nuclear maturation progression, mitochondrial membrane potential (MMP) and developmental competence of physiologically mature (22 h) and in vitro aged oocytes (30 h of IVM) obtained from prepubertal and adult females, either supplemented with UA or not were assessed. Additionally, the amount of mRNA of several genes (NFE2L2, NQO1, and mt-DN5) and the number of mt-ND5 DNA copies were quantified in cultured GCs from prepubertal and adult females, either supplemented with UA or not. Our study confirmed the harmful effect of oocyte aging on the nuclear maturation progression, MMP, developmental competence and gene expression levels. UA treatment during in vitro maturation enhanced (p &lt, 0.05) the maturation rate and subsequent developmental capacity of aged oocytes. A positive effect (p &lt, 0.05) of UA on physiological maturation, MMP and embryonic development was also identified. UA also interfered on the expression profile of NFE2L2 and NQO1 genes in GCs cultures. Our findings demonstrate that UA supplementation is an effective way to prevent oocyte aging and improves the subsequent bovine embryonic development.

The boné drilling is a common surgical procedure in clinicai intei-ventions including the dentistry. Although not a novelty in medicine, the penetration of a sharp tool in the boné tissue continues to be a clinicai and surgical challenge, as many pertinent questions still remain without solutions. Mechanical damage to the boné tissue is one of the common complication associafed with the drilling process [l]. An excessive force generated by a cutting tool can lead to the formation of microcracks and fractures, and even cause permanent damage in the boné tissue that, in tum, can delay postoperative recovery [2]. The main goal of this paper is to investigate the effect of drill speed on mechanical damage during drilling of solid rigid foam materiais, with similar mechanical properties to the human boné. Experimental tests were performed on biomechanical blocks instrumented with strain gauges in different surface positions during the drilling process. Finite element (FE) simulations were performed to simulate the drilling process and validated with experimental results.