Thesis (M.Sc.) - Cairo University - Faculty of Oral and Dental Medicine - Department of Prosthodontics

This study evaluated the amount of retraction and tissue reversibility produced by three different impregnated designs: Knitted, braided and twisted retraction cords impregnated with epinephrine and control group-nonimpregnated braided retraction cord. Fourty volunteers with healthy gingiva were chosen for this study. They were divided into two groups according to their gingival biotype: thick and thin gingiva biotype. The amounts of retraction were measured in two methods: in vivo and in vitro measurements. In vivo, the gingival sulcus dimension was measured by omnicam software. In vitro, the gingival sulcus dimension was measured on cast by Omnicam which was produced by impression taken using two phase two step technique in a sectional stock tray. In tissue reversibility, TNF-alpha level in gingival crevicular fluid was measured at baseline, two, seven, fourteen and twenty eight days after retraction. The results showed in both vivo and vitro measurements, there was a statistically significant difference between the four retraction cords used. Knitted cords showed the highest mean of retraction followed by braided, then twisted and finally non-impregnated braided retraction cord with lowest mean of retraction

Issued also as CD