OBJECTIVE The purpose of this study was to evaluate the root surface roughness after instrumentation with hand curette and diamond-coated sonic and universal ultrasonic tips. MATERIALS AND METHODS Forty root surfaces of human teeth were randomly assigned to four treatment groups: control group (without instrumentation), curette instrumentation, ultrasonic instrumentation with universal tip an...

this paper is based on a research carried out for evaluation of addict rehabilitation centers in iran. the research has been conducted by application of survey method, questionnaire technique and interview with help seekers (addicts) in qarchak varamin rehabilitation and de-addicion center in south- eastern of tehran. this study has been carried out in two stages of pre-treatment and rehabilita...

The RD-114 virus rapidly induced syncytia in the human transformed cell lines, RSa, RSb and IFr. Treatment of the virus with heat or ultrasonic vibration completely eliminated the syncytium-forming activity. Irradiation with u.v.-light or treatment with beta-propiolactone (BPL) reduced but did not completely destroy the activity. Pre-treatment of the cells for 16 h with 25 to 500 units/ml of hu...

This communication reports that the electron-transfer rate and surface roughness of Au electrodes can be decreased simply by ultrasonic treatment. It seems that the hydroxyl radical generated during ultrasonic treatment plays an important role, as in the case of treatment with Fenton's reagent.

OBJECTIVES To compare the effectiveness and safety of ultrasonic and pneumatic lithotripters in the treatment of renal stone disease. MATERIALS AND METHODS A total of 227 consecutive percutaneous nephrolithotomy procedures for renal calculi were performed. In 107 patients ultrasonic lithotriptors were used (group I) and in 83 patients pneumatic lithotriptors were used (group II). In the remai...

OBJECTIVE To evaluate the effects of ultrasonic instrumentation with different scaler-tip angulations on the shear bond strength (SBS) and bond failure mode of metallic orthodontic brackets. METHODS Adhesive pre-coated metallic brackets were bonded to 72 extracted human premolars embedded in autopolymerizing acrylic resin. The teeth were randomly divided into 3 groups (n = 24 each) to undergo...

The effect of 20 kHz ultrasound on the viability of Cryptosporidium oocysts was investigated. More than 90% of the dispersed Cryptosporidium oocysts could be deactivated in about 1.5 min of continuous sonication. In order to apply this technique to large quantities of contaminated water, quantitative filtration and redispersion of Cryptosporidium oocysts were investigated and found to be easily...

Methods There are three arms of the study: de novo stones, postlithotripsy fragments, and large stones within the preoperative setting. A pain questionnaire is completed immediately prior to and following propulsion. A maximum of 40 push attempts are administered on either low (50 V) or high (90 V) power settings. Movement is classified as no motion, movement with rollback (2-3 mm), or movement...

Ultrasonic measurements have been performed for comprehensive microstructural characterisation in 9 % Cr ferritic steels. The variation in grain size, the effect of solution annealing temperature on microstructure developed, the variation in microstructure of the weld joints, the effect of post weld heat treatment and precipitation behaviour during thermal ageing and creep testing have been suc...

background: bisphenol-a is categorized as a toxic and refractory organic matter. ultrasonic process considered as an effective method for degradation of refractory organic matters in the environment which is achieved by the production of fine bubbles through cavitation process. this study is conducted for assessment of the toxicity of effluents containing bisphenol-a which was treated by ultras...