Class II Division 1 Malocclusion
Conditions
Brief summary
The aim of this study is to assess skeletal (bone) and dental (teeth) changes occurring following wear of a twin block functional appliance (removable brace which postures the lower jaw forward to improve a discrepancy between the upper and lower jaw) for differing time periods.
Detailed description
Functional appliances are ordinarily worn full time in adolescence between 11 and 14 years with a discrepancy between their upper and lower jaws. The reason it is worn between these ages is to avail of the pre pubertal growth spurt, evidence for full time wear is merely empirical.If this appliance only had to be worn part time it would have a significant change in orthodontics in terms of patient acceptance and compliance.The investigators plan on recruiting 84 patients to the study and these subjects will be referred from hospital colleagues. The investigators will randomly allocate the subjects into 2 groups, Group 1 will wear the appliance Full Time(24hours), group 2 will wear the appliance part time(12hours). The study will be conducted in the Dental Institute at the Royal London Hospital, this hospital setting will be the sole site. The study will last for 15 months from the time the last patient is recruited. Participants will undergo an initial records appointment where a radiograph and clinical measurements will be taken followed by 12 months of functional appliance treatment where the patient will be reviewed at 6-8weekly intervals and clinical measurements taken.A final radiograph will be taken at 15months.
Interventions
DEVICEModified Clark Twin Block
The Modified Clark Twin Block is a type of functional orthodontic appliance used to posture the lower jaw forward to treat discrepancies between the upper and lower jaw bones
Sponsors
National Health Service, United Kingdom
Queen Mary University of London
Study design
Allocation
RANDOMIZED
Intervention model
PARALLEL
Primary purpose
SUPPORTIVE_CARE
Masking
NONE
Eligibility
Sex/Gender
ALL
Age
11 Years to 14 Years
Healthy volunteers
Yes
Inclusion criteria
* Class II div 1 malocclusion(upper front teeth lying more forward than lower front teeth with upper front teeth proclined), * Overjet(horizontal difference between upper and lower front teeth) measuring minimum of 7mm, * Male subjects 12--14 years at the start of treatment, * Female subjects 11--13 years at start of treatment, * Willingness of the patient and parent to participate in the study.
Exclusion criteria
* No previous orthodontic treatment * No relevant medical history or craniofacial syndrome
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| remaining overjet measured with an orthodontic ruler | outcome measure will be assessed after 12 months appliance wear and after a 3 month relapse period | the initial overjet will compared to the final overjet following 12 months of appliance treatment, and 3 months of relapse. overjet will be measured with an orthodontic ruler at every review appointment |
| Cephalometric Changes | Outcome will be assessed after 12m of appliance wear and after 3 months of settling. | Both linear and angular cephalometric changes will be assessed over this timeframe. |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| Comparison of subjective and objective measures of appliance wear | 12 months of appliance wear | Subjective (patient completed time charts) and objective (theramon micro-sensor) measures of wear will be assessed over 12months of appliance wear. |
Countries
United Kingdom
Outcome results
None listed