الفهرس 
IntroductionOnly 14 pages are availabe for public view
 |  | from | 155 |  |  |
| | | from | 155 | | |
Abstract
This study was designed to assess gingival response to laser crown lengthening under different operating modes: continuous peak pulsed and chopped, using different restorative material, full metal crowns and all aramic crowns, with different surface finish at different time intervals; 48 hours, 10days and 6 weeks.
General anaesthesia were administered for 24 days, laser soft tissue crown lengthening was performed to the level of attached gingival. 48 teeth (in words) were prepared to receive secondary impressions were taken, temporary cemented over the prepared teeth till permanent crowns fabrication.
After 48 HRs, permanent crowns were cemented over the prepared teeth after the dogs, had been generally anasthesied agin dogs were sacrificed per group per time interval.
In histomorphametric analysis, the specimens were prepared and digital images were made using stereo-microscopy (Olympus Bx 61; Olympus) e quipped with high resolution camera (E330; Olympus imaging Corp). The analysis was performed using image analysis software (Olympus cell m & cell R V3.3; Olympus soft imaging solutions for the determination of the following; vertical and horizontal tissue locations and epithelial evaluation; keratinized, partial keratinized and ulceration.
Repeated measures analysis of variance (ANOVA) was used to study the effect of material, operating mode, time, surface finish and their interactions on mean vertical & horizontal locations.