الفهرس 
INTRODUCTIONOnly 14 pages are availabe for public view
 |  | from | 119 |  |  |
| | | from | 119 | | |
Abstract
This study aimed to evaluate the shear bond strength and microleakage of Vertise Flow when used as a pit and fissure sealant and compare it to a conventional pit and fissure sealant. A total of sixty sound premolars extracted for orthodontic purposes were employed in this study.
Thirty premolars were randomly divided into two equal groups. The crown of each tooth was separated from the root 2mm below the cemento-enamel junction. each crown was then mounted in self cure acrylic resin inside cylindrical metal mold with their sound buccal surface displayed perpendicular to the long axis of the block. all specimens were ground flat using 800 grit silicon carbide finishing paper then the sealant materials were applied using a plastic mold. Specimens were mounted in Universal Testing Machine where shear bond strength was measured for each specimen by determining the force required to dislodge the sealant from the enamel surface. Each specimen was then examined under a light stereomicroscope to determine the location and mode of failure. Vertise Flow showed significantly higher shear bond strength than Clinpro sealant.
For microleakage evaluation, thirty premolars where randomly divided in two equal groups according to the sealant material. All teeth were mounted in self-cure acrylic resin blocks with occlusal surface facing upward. Occlusal surfaces were sealed with the sealant materials according to the manufacturers’’ recommendations. Teeth were then thermocycled in water bath for 500 cycles alternating between 5°C- 55°C with dwell time 30 seconds using thermocylcing machine. After thermocycling, all teeth surfaces were coated with 2 layers of nail varnish except for 1mm around the sealant margins. Teeth were then immersed in 1% solution of methylene blue for 24 hours. Finally, teeth were dried and sectioned buccolingually through the sealant using diamond saw resulting in two sections for each specimen. The extend of dye penetration was detected using light stereomicroscope. Vertise flow showed significant lower microleakage score compared to that of Clinpro sealant.
Based on the results of this study, Vertise Flow showed better retention and sealing ability to enamel than Clinpro sealant which encourage its use as pit and fissure sealant.