Class III Malocclusion, Underbite
Conditions
Keywords
Class III Malocclusion, Orthodontic retention
Brief summary
The purpose of this study is to evaluate the effects of adding elastics to orthodontic retainers on the stability of class III correction and whether it reduces the need for jaw surgery.
Detailed description
Over the years many types of appliances have been recommended for retaining Class III correction in growing children such as intermaxillary splints, class III activator, Frankel 3, Class III twin block, continued use of face-mask and chin-cup. However, currently none of these are in routine use and there is no evidence on the long term effectiveness of any retention protocol for class III correction. One of the most commonly used retainers following orthodontic treatment is clear plastic retainers. There are no studies that investigated whether using class III elastics in combination with clear plastic retainers improves the stability of class III correction and reduces the need for later jaw surgery.
Interventions
OTHERUpper-lower clear plastic retainers + Class III elastics
Addition of Class III elastics to clear plastic retainers
OTHERUpper-lower clear plastic retainers
Upper-lower clear plastic retainers
Sponsors
Sydney Local Health District
Study design
Allocation
RANDOMIZED
Intervention model
PARALLEL
Primary purpose
PREVENTION
Masking
SINGLE (Outcomes Assessor)
Eligibility
Sex/Gender
ALL
Age
12 Years to 16 Years
Healthy volunteers
Yes
Inclusion criteria
* Patients that completed their orthodontic treatment for the management of their skeletal class III with upper jaw retrusion that was treated with Class III orthopaedic appliances, followed by full fixed appliances. * No congenital anomalies or craniofacial syndromes * No other orthodontic treatment * No medical history that effects growth
Exclusion criteria
* Congenital anomalies or craniofacial syndromes * Other orthodontic treatment * Medical history that effects growth
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Difference in overjet of participants in the 2 study arms | 5 years | Measurement of overjet |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| Need for jaw surgery | 5 years | Need for surgery assessed by a panel of orthodontists |
| Difference in upper jaw position | 5 years | The difference in SNA angle measured on cephalometric radiographs between groups |
| Difference in lower jaw position | 5 years | The difference in SNB angle measured on cephalometric radiographs between groups |
| Difference in upper-lower jaw relationship | 5 years | The difference in ANB angle measured on cephalometric radiographs between groups |
| Difference in upper incisor angulation | 5 years | The difference in upper incisor angle measured on cephalometric radiographs between groups |
| Difference in lower incisor angulation | 5 years | The difference in lower incisor angle measured on cephalometric radiographs between groups |
| Compliance and ease of use of both retention regimens | 5 years | Questionnaire on the frequency and ease of use of both retainer regimens will be used |
| Effect of elastics on alignment retention | 5 years | Little's irregularity index will be used to compare both groups |
| Periodontal health, including recession around the incisors | 5 years | Presence of gingival recession and prominence of lower incisors will be evaluated for both groups |
Countries
Australia
Contacts
PRINCIPAL_INVESTIGATOROyku Dalci, DDS, PhD
Sydney Local Health District, The University of Sydney
Outcome results
None listed