INTRODUCTION Thermal changes can occur on the external root surface when root-end cavity preparation is performed, which may damage periodontal ligament cells and alveolar bone. OBJECTIVE The purpose of this study was to evaluate the temperature changes during preparation of the root-end cavities at 1 and 3 mm to the sectioned apical root surfaces when either tungsten carbide round bur, diamo...

Nano ZnO/ montmorillonite composite were prepared by sol gel method under ultrasonic irradiation from directly mixing montmorillonite nano clay into Zinc gel. The Zn(CH3COO)2.2H2O and montmorillonite nano clay was used as precursor. The zinc acetate was dissolved in DI water and, NH3 (aq) solution was dropped into the zinc solution until pH 9 consequently the zinc gel was produced. The montmori...

In this study, response surface methodology (RSM) based on central composite design (CCD) was applied for investigation of the effects of ultrasonic waves, temperature and solvent concentration on viscosity reduction of residue fuel oil (RFO). Ultrasonic irradiation was employed at low frequency of 24 kHz and power of 280 W. The results showed that the combination of ultrasonic waves and solven...

Background/introduction Bone is highly relevant to focused ultrasound therapy, both as a potential treatment target and because it interferes with treatment of other organs such as the brain. It is challenging to image cortical bone using MRI, however, due to low water density and fast signal decay in bony tissues. Ultrashort echo time (UTE) imaging is a specialized MR technique that allows the...

BACKGROUND Phytosterols have important physiological and officinal function. METHODS An efficient ultrasonic assisted extraction, purification and crystallization procedure of phytosterols was established from corn silk for the first time. RESULTS The orthogonal test was applied to optimize the process parameters and a maximum phytosterols recovery as high as 10.5886 mg/g was achieved by ul...