الفهرس 
CONTENTSOnly 14 pages are availabe for public view
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Abstract
In the present investigation, a total of 480 specimens were used for qualitative “SEM”and quantitative, Ra values,, assessment the surface texture of enamel and dentine prepared by cutting, abrading at various speeds, when air and air/water spray were used coolants. In addition, the effect of lazing at 30 and 60 J/cm2 intensity with different pulses 1,3,5, and 7 pulses werestudied. Surface texture measurements and scanning electron microscopic examination of the enamel and dentine specimens after cutting abrading or lazing were done to reveal the effects of the 48 variables being studied. The Teeth were equally divided into two main groups, 240 specimens each, relative to the type of the hard tooth tissue being used,i.e., enamel or dentine. Each group was then equally subdivided into three main subgroups, 80 specimens each, relative the preparation technique used, i.e., cutting, abrading or lazing. The first subgroup, prepared by cutting technique with No.2 plain-cut carbide fissure bur, 80 specimens, was further divided, into four main divisions, 20 teeth each, relative to the speed ranges being used, i.e., low and high conventional, high and ultra-high speed ranges. Each division was further equally subdivided into two subdivisions, 10 teeth each, relative to the type of coolant being used, i.e., air or air/water spray cooling system.