Nada Abdelhamid Abdel creator preparation. Somaya A. Bayoumy thesis advisor. Fatma Ahmed Abed thesis advisor. text theses ua 2021 monographic eng ara 184 pages : illustrations ; 30 cm. + CD. The current study was conducted to investigate the effect of wire gauge on rate and type of tooth movement during sliding mechanics and its effect on root resorption of the teeth moved and amount of anchorage loss. Total of 36 canines of eighteen adult female patients with age range (16-26) years old who had dento-alveolar maxillary protrusion necessitating extraction of the maxillary first premolars were investigated in the study. Canines were retracted using Ni-Ti coil spring extending between canines’ brackets and second molars’ tubes which was used for anchorage while no additional anchorage means were used. Canines were retracted with 1.5 N force over three archwire gauges (0.016Ⅹ0.022”, 0.017Ⅹ0.025” and 0.19Ⅹ0.025”) St.St wires in three-arm parallel group study. 3D digital models were used in the assessment of monthly canine retraction rate, which was the primary outcome of the study and amount of first molar anchorage loss that was secondary outcome. CBCT images were used in the assessment of other secondary outcomes; amount of canine root resorption, change in canine tipping, torque and rotation occurred after 6 months of retraction. The results revealed that there was small difference in the mean rate of canine retraction between the three groups as canine was retracted by 1.01, 0.67 and 0.7 mm/month in 0.016Ⅹ0.022”, 0.017Ⅹ0.025” and 0.19Ⅹ0.025” St.St groups, respectively with no statistical significant difference between all groups (P-value=0.2). Canine tipping increased with the decrease in archwire gauge yet that tipping was of no statistical or clinical significant difference (P-value=0.085, CI= 8.15-11.42). Root resorption was significantly higher in 0.19Ⅹ0.025” St.St group 1.39±1.23 mm than the other two groups (0.5±0.66 and 0.41±0.55) mm in 0.016Ⅹ0.022” and 0.017Ⅹ0.025” St.St groups (pvalue=0.024). Additionally, there was statistical significant difference between 0.016Ⅹ0.022” and 0.017Ⅹ0.025” St.St groups regarding amount of anchorage loss (P-value=0.028) with no statistical significance between any other two groups. The mean value of anchorage loss was 1.71, 2.99 and 2.72 mm in 0.016Ⅹ0.022”, 0.017Ⅹ0.025” and 0.19Ⅹ0.025” St.St correspondingly. For the other outcomes, there was no significant difference among the groups specialized Nada Abdelhamid Abdel ; Somaya A. Bayoumy, Fatma Ahmed Abed Thesis (M.Sc)-Cairo University, 2021. Bibliography: pages 174-180. Issues also as CD. Text in English and abstract in Arabic & English. Nursing Administration Organizationalsupport Burnout Nursingstaff 613 EG-GICUC 260421 20260421115936.0 eng