الفهرس 
Intramaxillary noncompliance distalization appliancesOnly 14 pages are availabe for public view
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Abstract
Maxillary molar distalization is one of the most frequently used orthodontic treatment modalities for the correction of a Class II molar relationship. The use of so-called “distalization” mechanics to correct Class II malocclusions is a common treatment modality. Many devices have been developed and used to distalize the maxillary molars and show positive clinical results. Bone anchorage pendulum appliance (BAPA) and Lever arm miniimplant system (LAMS) were the appliances used in the current study for molar distalization. The purpose of this study was to evaluate and compare the dentofacial changes after distalization of maxillary first molars in dental Class non-extraction cases. The sample consisted of 30 patients with Class II molar relation where their molar distalized with either BAPA (n = 15) or with LAMS appliance (n = 15). Their ages were ranged from 16-22 years at the start of the treatment. Dental casts and lateral cephalometric x-rays were obtained before and after distalization. Angular, horizontal and vertical changes were recorded to investigate the dental and skeletal changes produced by both appliances. The differences between the pretreatment and the posttreatment data in both groups, the differences in the treatment effects between the two groups and the duration of distalization were analyzed with student t test and the foundation was: • The distalization time in LAMS group is significantly longer (10.56 months) when compared with BAPA group (7.2 months). • Highly significant increase in the maxillary arch perimeter was found in both groups mainly by distalization of maxillary first molars without anchorage loss. • There was highly significant distal tipping of the maxillary first molar in BAPA group with less distal tipping in lever-arm and mini-implant system group. • The significant distal movement of the maxillary second premolars, first premolars and central incisors in both group would positively affect the prognosis. • The lever-arm and mini-implant system is an effective appliance for intraoral molar distalization without distal tipping or anchorage loss. • The changes in the maxillary first molar rotational axis angle were not significant between the two studied groups. However. there was a significant difference of maxillary first premolar rotational axis angle changes between the two groups. • The posterior facial height was not affected while there was an increased lower facial height in BAPA consequently the total facial height showed a larger dimension after distalization in the LAMS group. • The increase in the maxillary intermolar width was highly significant in both groups. This increase was similar between the two groups. • Highly significant increase in the maxillary arch perimeter was found in both groups, which was greater in BAPA group, indicating more distal tipping. • Insignificant differences in the sagittal skeletal measurements (SNA, SNB and ANB angles) were found. Consequently, the effect of both appliances was mainly dentoalveolar in nature.