Bond and rebond strengths an in vitro and in vivo evaluation


New orthodontic adhesives should be put under vitro and vivo investigation to evaluate their efficiencies and disadvantages, so that, Concise, No Mix and Right On orthodontic adhesives were tested in vitro and evaluated clinically by treating (15) cases. These adhesives were used in bonding (10) human sound extracted premolars for each one according to the manufactures instructions, and then rebonded new brackets to these tested teeth after cleaning and polishing.The adhesive were used in bonding the brackets to the 40 teeth clinically (five upper dental arches) for each type, according to their manufacturer ' s instructions. The lowest number of failure brackets was within the use of concise adhesive.The shear bond and rebond strength were measured in compression test Machine in Mega Pascal (Mpa).The results showed that the Concise adhesive had strongest bond and rebond strength in vitro and clinically than that No Mix and Right-On adhesives and the later adhesives had adequate bonds strength and more successful in bonding anterior brackets