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Functional regulator treatment of Class II division 1 malocclusions
S M Chadwick1, J C Aird, P J Taylor
1Countess of Chester NHS Trust, Health Park, Liverpool Road, Chester, UK.
European Journal of Orthodontics
|October 24, 2001
Summary
The Fränkel appliance effectively corrects Class II division 1 malocclusions, primarily through significant dental changes rather than substantial skeletal alterations. This functional regulator II (FRII) treatment offers desirable occlusal improvements for most patients.
Area of Science:
- Orthodontics
- Craniofacial Development
- Dental Biomaterials
Background:
- Class II division 1 malocclusions present complex challenges in orthodontic treatment.
- Functional appliances are widely used to address these discrepancies.
- Understanding the specific contributions of skeletal and dental changes is crucial for treatment optimization.
Purpose of the Study:
- To evaluate the skeletal and dental changes associated with Fränkel's functional regulator II (FRII) treatment.
- To compare treatment effects in patients with Class II division 1 malocclusions against a control group.
- To determine the efficacy of FRII in correcting malocclusions.
Main Methods:
- Controlled retrospective study design.
- Inclusion of 138 patients with Class II division 1 malocclusions (70 treated with FRII, 68 controls).
- Analysis of pre- and post-treatment cephalometric radiographs.
Main Results:
- Statistically significant skeletal changes (SNB, ANB, BaNA, ANS-Me) were observed but lacked clinical significance.
- Clinically and statistically significant dental changes included a 10-degree reduction in upper incisor to maxillary plane (UI-Max) and a 3.1-degree increase in lower incisor to mandibular plane (LI-Mand).
- The Fränkel appliance demonstrated effectiveness in achieving desirable occlusal and dental outcomes.
Conclusions:
- Fränkel's functional regulator II (FRII) is effective in correcting Class II division 1 malocclusions.
- Treatment outcomes are primarily driven by significant dental modifications rather than substantial skeletal changes.
- FRII provides a viable orthodontic solution for achieving improved occlusion.
