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Abstract. NiTi endodontic files allow for clinical enlargement of harshly curved root canals. However, files rotated under severe flexion might fracture unexpectedly, remain inside teeth and thus, hinder treatment outcome. ProFile .06(35) are among the most commonly used rotary files. In the present study, 10 of these brand new instruments were used to perform DSC on their cutting regions and determine the amount of R-phase present at 10, 20, 37, and 65ºC, both during cooling and heating programmed cycles. Another 48 new ProFile .06(35) instruments underwent rotation/flexion assays at 300 rpm and 10 mm radius of curvature. Files were divided into four groups of 12 instruments each. Each group was tested at 10, 20, 37, and 65ºC. The number of cycles to fracture (N f ) and the length of the broken segment (L f ) were determined for each tested file. Results show no statistically s as for L f in all groups. On the contrary, N f depends highly on testing temperature: as temperature increases from 10 to 37 ºC, N f strikingly decreases; from 37 and 65 ºC, no significant changes in N f occur. As for DSC results, it is clearly shown that R-phase is most abundant at 10 ºC and consistently decreases up to 37ºC, both during heating and cooling; from 37 to 65 ºC, the quantity of R-phase in the alloy is negligible. In conclusion, it is shown that fatigue resistance in ProFile .06(35) instruments is not only highly enhanced but also proportional to the amount of R-phase in the alloy. BackgroundRoot canal degree of curvature is highly dependent on tooth type [1-3] as canal shape roughly corresponds to its root shape [4]. Endodontic literature agrees on most root canals having some degree of curvature [5]. Stainless steel files produce more canal transportation in curved canals than their Ni-Ti rotary counterparts, both in acrylic simulated root canals [6,7], and in extracted teeth [8,9]. Dalton et al. [10] showed, in vivo, that Ni-Ti files and stainless steel files are equally effective in reducing intracanalar bacteria when matched for size. However, if more tapered Ni-Ti files are used, then rotary files allow for better irrigation at working length [11,12] and, hence, for a better apical cleaning. The faster results obtained with Ni-Ti rotary files [13,14] have also made them increasingly popular among clinicians and their use is now even taught at undergraduate level [15][16][17].The major drawback of Ni-Ti instrumentation is file rupture. Iqbal et al. [18] report that the odds for rotary Ni-Ti file breaking were seven times more than for hand stainless steel file separation in graduate clinical setting. Spili et al. [19] report similar findings in a population of experienced endodontists, which accounts for the overall perception among general practitioners that Ni-Ti files break more often than hand stainless steel files [20]. Reliable data on Ni-Ti fragments that remain inside root canals is still scarce. Spili et al. [19] are, so far, the only authors who investigated the influence of retained Ni-Ti fragments on p...

According to Vânia (2006) due to urban growth and development, the common spaces (streets, parks, fields, etc.), in which the child manifests its motor skills, are being decharacterized from civil construction, which has been delimiting their space, preventing the flow of better preparation for them. Manchúra and Manzano (2017) emphasize that due to the environment and living conditions in which we find ourselves, we detain a certain resistance in acquiring motor knowledge among children. The absence of this flow of physical activities can delimit the individual in several particularities of their improvement, motivating beyond their motor performance, in perception and social conduct.For Barreto (2004), the child's development is fundamental, so that he/she has control over his/her body, developing and improving his/her alternatives to move, causing the discovery of new spaces and ways to overcome his/her limitations and circumstances to confront the challenges according to the principles, propulsive, sociable, sensitive, and intellectual.According to Papalia and Olds (2017) it is through the movement of the body that the child evolves, it is in the school phase that the child can coordinate his muscles, solving his bodily needs, thus, this phase is considered a time of important changes, because the child gains skills and autonomy.Recent studies emphasize dance as a mechanism capable of improving the motor stimulus of children, managing to be in the same way an extremely spontaneous practice. Ribas (1992) tells us that, for the human being, dance can be instinctive, as a way to communicate, to distract oneself, to smile or even to cry; this is because dancing is a manifestation of emotions. The human being has been moving since the beginning of his earthly existence, that is, since he left his ignorant condition and conquered his rational condition.

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