الفهرس 
Suggested mechanisms of acid resistanceOnly 14 pages are availabe for public view
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Abstract
This in vitro study was designed to evaluate the effect of two surface treatments (Acid etching, Laser etching), for two types of enamel structure (Aprismatic enamel, prismatic enamel), On the bond strength with two types of resin cements (Light cured adhesive resin cement, Dual cured adhesive resin cement).
Fifty six natural central incisors were used. The specimens were divided into two groups according to the preparation, Each group were subdivided into two subgroups according to type of surface etching (surface treatment), Each sub group were further subdivided into two divisions according to the type of the resin adhesive cement used.
Both prepared (prismatic) and unprepared (aprismatic) teeth were etched using phosphoric Acid etchant gel with 37% concentration for 15 seconds using a copious amount of acid etchant gel then rinsed using water for another 15 seconds
Both prepared (prismatic) and unprepared (aprismatic) teeth were etched using erbium, chromium: yttrium, scandium, gallium, garnet [Er,Cr:YSGG] hydrokinetic dental laser.
An even layer of universal bond applied then Each tooth received resin micro-cylinder. Iris of polyethylene tube having 1mm diameter and 1mm height was positioned over the tooth surface, and filled with resin cement, creating resin micro-cylinder having the same dimensions.
A loop prepared from an orthodontic wire (0.014‖ in diameter) was wrapped around the bonded micro-cylinder assembly as close as possible to the base of the microcylinder and aligned with the loading axis of the upper movable compartment of the testing machine. A shearing load with tensile mode of force was applied via materials testing machine at a crosshead speed of 0.5 mm/min. The load required for de-bonding was recorded in Newton.
Then the data obtained were collected, tabulated and then subjected to statistical analysis.