الفهرس | Only 14 pages are availabe for public view |
Abstract This study aimed to evaluate the dento-skeletal effects of intrusion of the lower incisor teeth by mini-screws. Ten patients were selected from the outpatient clinic of the Department of Orthodontics, Faculty of Dentistry, Mansoura University with Angle’s Class II division1 malocclusions. The age of the patients ranged from 15 to 18 years (15.4 year mean) with deep overbite (more than 1/3 the crown height of the lower incisors covered by the upper incisors) requiring intrusion of the lower incisors. Fixed orthodontic appliance was fitted for every patient and after alignment of the first molars, second premolars and canines without inclusion of the lower four incisors ; the cuspids were retracted on 16×22 inch stainless steel archwire. Two mini-screws as anchorage for the lower incisors segment intrusion were inserted for every patient between the lateral incisor and the cuspid one in each side and connected to a utility arch wire by power chain to apply intrusive force. The mean of overbite correction was 4.2 mm and lower incisors were intruded significantly by a mean of 3.55 mm with 4.25° labial flaring. There were insignificant increasing in the antero-posterior skeletal measurements, also vertical skeletal dimensions showed no significant changes. In Conclusion: the mandibular incisors were effectively intruded by using mini-screws as orthodontic anchorage with no significant counteractive movements in the molars. Key words : Class II division1 malocclusions -Deep overbite – Intrusion –Mini-screws. |