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OBJECTIVES: Human intrapupal tooth temperature is considered to be similar to that of the body (≈37 °C), although the actual temperature has never been measured. This study evaluated the in vivo, human, basal, coronal intrapulpal temperature of anesthetized upper first premolars. METHODS: After approval of the local Ethics Committee was obtained (protocol no. 255,945), upper right and left first premolars requiring extraction for orthodontic reasons from 8 volunteers, ranging from 12 to 30 years old, received infiltrative and intraligamental anesthesia. The teeth (n=15) were isolated using rubber dam and a small, occlusal preparation was made using high-speed handpiece, under constant air-water spray, until a minute pulp exposure was attained. The sterile probe from a wireless, NIST-traceable, temperature acquisition system (Thermes WFI) was inserted directly into the coronal pulp. Once the probe was properly positioned and stable, real-time temperature data were continuously acquired for approximately 25 min. Data (°C) were subjected to 2-tailed, paired t-test (α=0.05), and the 95% confidence intervals for the initial and 25-min mean temperatures were also determined. RESULTS: The initial pulp temperature value (31.8±1.5 °C) was significantly lower than after 25-min (35.3±0.7 °C) (p<0.05). The 95% confidence interval for the initial temperature ranged from 31.0 to 32.6 °C and from 35.0 to 35.7 °C after 25 min. A slow, gradual temperature increase was observed after probe insertion until the pulp temperature reached a plateau, usually after 15 min. SIGNIFICANCE: Consistent coronal, human, in vivo temperature values were observed and were slightly, but significantly below that of body core temperature.

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Objetivo: Este estudo propõe-se avaliar a perda de corte do instrumento rotatório ProTaper® em função do número de uso e esterilização em autoclave. Método: Foram estudados 10 canais simulados de resina acrílica transparente com ângulo de curvatura de 45º, valendo-se de instrumentos Protaper® de numeração S1, S2, F1, F2 e F3, substituindo o Sx pelas brocas de Largo #1. Os blocos foram pesados em balança analítica digital, anotando-se o peso inicial. A seguir, houve o preparo com motor elétrico Endo Pro-Torque® da Driller com reverso automático submetido ao ajuste e controle da velocidade em 350 rpm, torque de 1N, com engate para contra-ângulo modelo Kavo®, tomando-se o cuidado de padronizar o tempo de ação de cada instrumento em 3 minutos. Usou-se o creme de Endo-PTC durante o preparo do canal simulado e após seu tempo de ação, lavava-se o canal com hipoclorito de sódio. Depois, o bloco era lavado com detergente neutro, seco com gaze, canal aspirado, seco com cone de papel absorvente, pesado, anotando-se o peso final. A cada uso as limas rotatórias eram limpas com gaze embebido em álcool e, posteriormente, lavadas com detergente neutro e secas também com gaze e levadas em envelope descartável para processo de esterilização em autoclave com ciclo de 20 minutos. Resultados: Os instrumentos utilizados perderam a sua capacidade de corte em função do número de uso. Conclusão: O instrumento perde a capacidade de corte em função do uso, e só a partir do sé¬timo uso, o instrumento ProTaper® perde consideravelmente sua efetividade, recomendando-se seu descarte

Aims: This investigation aims to evaluate the cutting loss and sterilization of rotary ProTaper® instrument for sterilization process in autoclave. Method: Were studied ten substrate resin simulated canals blocks numbered 1 to 10 with angle of 45º. Before and after instrumentation were used with ProTaper® files numbering S1, S2, F1, F2, F3, is substituting for the Sx Largo drills # 1. These blocks were weighted using an analytical digital scale model Mettler AJ 100 and following it were analyzed of the amount of resin removed in each sample were noted both initial and final weight. The instrumentation was made with Endo-Pro-Torque engine-driven Driller system with automatic reverse and speed control in 350 rpm, torque 1N using stop watch for standardize the 3 minutes time of each instrument. Cream Endo-PTC was used during instrumentation e after that, washing the canals with 5mL the distillate water with plastic syringe. The blocks were washed with detergent, dry with gauze, aspirated canal, dried with paper absorbent points, weighted and noted final weight. In each use the files were clean with gauze alcohol soaked and later washed with detergent and dried with gauze and put in recipient discard able for sterilization in autoclave Sercon model during 20 minutes. Results: The instruments used have lost the cutting ability in relation to the number of use. Conclusions: It?s concluded that occurred a loss of efficiency of the cutting instrument, however the instrument ProTaper loses its cutting ability in use only after the seventh use and thus it?s recommended its discard

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El objetivo de este trabajo fue el de evaluar la microfiltración marginal producida en cavidades cuya profundidad alcanzaba a la dentina en dientes bovinos. Con esta finalidad fueron confeccionadas cavidades utilizando dos sistemas diferentes de preparación: punta diamantada CVD ultrasónica y puntas diamantadas en alta rotación. Una vez terminada la preparación de las cavidades estas fueron restauradas con resina compuesta para a seguir, los cuerpos de prueba ser almacenados en una solución de suero fisiológico durante una semana tiempo después del cual fueron preparados para realizar a los ciclos térmicos correspondientes para posteriormente realizar su inmersión en una solución de fucsina básica a 0.5 por ciento. Los cuerpos de prueba fueron cortados y lijados para poder observarlos en el microscopio óptico. La medición cuantitativa de la microfiltración marginal fue realizada por medio de la imagen digitalizada y de un software específico. Al someter los resultados al análisis estadístico de Mann-Whitney fue comprobada una acentuada infiltración marginal en ambos grupos sin mostrar diferencia estadística significativa entre ellos, sugiriendo como consecuencia que la técnica de preparación cavitaria no tuvo influencia sobre la microfiltración marginal en restauraciones de resina compuesta

The aim of this study was to evaluate the marginal microleakage in cavities with depth in bovine tooth dentin. Cavities preparation were made in two groups using conventional diamond burs associated with air turbine and ultrasonic CVD diamond tip with ultrasound. Cavities were restored with composite resin and after thermocycled, teeth were immersed in basic fucsin, sectioned, sandpapered and analyzed by an optical microscope. Microleakage quantitative evaluation was obtained through a digitalized image and a software program. Mann-Whitney test showed high amount of marginal microleakage in both groups without any statistically significant difference, suggesting that cavity preparation technique had no influence on marginal microleakage of composite resin restorations

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