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

Aim: to evaluate the use of 3D Printed Modified Twin Block appliance in skeletal Class II growing females versus an untreated control group regarding skeletal Class II profile correction, inclination of anterior teeth, soft tissue convexity correction, correction of overjet and patient acceptance. Methodology: 19 growing females aged from 10-13 years old with skeletal Class II malocclusion were randomly divided into two groups. Group1(3D TB group) included 10 patients who were treated with 3D printed modified Twin Block appliance for 8 months, while group 2 (control) included 9 patients who were observed for 8 months without treatment. Lateral cephalograms were taken for each patient before and after treatment/ observation period to be analyzed. Results: A significant net increase of 1.83 mm in the effective mandibular length was found in the treatment group in comparison to the control group. Significant difference (P< 0.05) was found between both groups in overjet measurement; a significant net overjet reduction by 5.08 mm was observed in the treatment group.Significant upper incisor retroclination and lower incisor proclination were seen in the treatment group. Significant upper molar distalization by 1.24 mm was reported in the treatment group as well. Soft tissue convexity angle (N{u2018}-Sn-Pog{u2018}) and nasolabial angle significantly increased by 3.206 degrees and 9.13 degrees respectively in the treatment group with significant reduction in H angle and flattening of the mentolabial sulcus. Analysis of the patients acceptance questionnaire revealed increase in patients overall appliance acceptance over 6 months with significant increase regarding speaking with the appliance and effect on the facial appearance

Issued also as CD