Plain English Summary
Background and study aims
Orthodontic treatment with fixed braces is used to improve the appearance, position and function of crooked or abnormally arranged teeth. Fixed braces are made up of brackets that are glued to each tooth and linked with wires. Conventional (non-self-ligating) brackets use an elastic module to hold the wire in place, whereas self-ligating brackets do not. The aim of this study is to compare the results of these two types of orthodontic bracket, looking at changes in the width of the lower tooth arch.
Who can participate?
Patients aged between 11 and 21 who require fixed braces.
What does the study involve?
Participants are randomly allocated into one of the two groups. Each group is treated with braces with a different bracket system, either self-ligating brackets or non-self-ligating brackets. A questionnaire is used to assess patient pain and anxiety, and any appliance breakages are recorded.
What are the possible benefits and risks of participating?
Not provided at time of registration
Where is the study run from?
Queen Alexandra Hospital (UK)
When is the study starting and how long is it expected to run for?
December 2011 to December 2013
Who is funding the study?
Investigator initiated and funded
Who is the main contact?
Dr Becky Walker
Trial website
Additional identifiers
EudraCT number
ClinicalTrials.gov number
Protocol/serial number
11/SC/0421
Study information
Scientific title
A comparison of mandibular archwidth changes using two different bracket systems: a randomised controlled clinical trial
Acronym
Study hypothesis
Null hypothesis:
There is no significant difference in archform changes between self-ligating brackets and non-self ligating brackets using super elastic nickel titanium archwires
Ethics approval
NRES Committee South Central - Oxford A, 12/10/2011, ref: 11/SC/0421
Study design
Randomised controlled trial
Primary study design
Interventional
Secondary study design
Randomised controlled trial
Trial setting
GP practices
Trial type
Treatment
Patient information sheet
Not available in web format, please use the contact details below to request a patient information sheet
Condition
Orthodontics mandibular archform
Intervention
Patients will be randomised into one of the two arms of study. Each arm of study will use a different bracket system, either:
1. Self-ligating brackets (Damon Q)
2. Non self-ligating brackets
Treatment will then proceed with both bracket systems using the same archwire sequence:
1. 0.014 inch round NiTi archwire
2. 0.014x 0.025 inch Damon Copper NiTi archwire
3. 0.018x 0.025 inch Damon Copper NiTi archwire
Intervention type
Other
Phase
Not Applicable
Drug names
Primary outcome measure
Mandibular archwidth changes
1. Alginate impressions for study models of the maxillary and mandibular arches will be taken at:
T0: Before placement of fixed appliances, at the start of treatment.
T1: Removal of 0.014 inch round NiTi archwire and placement of 0.014 x 0.025 inch NiTi archwire
T2: Removal of 0.014 x 0.025 inch NiTi archwire and placement of 0.018 x 0.025 inch NiTi archwire
T3: Removal of 0.018 x 0.025 inch NiTi archwire and placement of next archwire
These study models will be used to measure mandibular archwidth between the 2 groups at T0, T1, T2, and T3 measured at 4 places across arch (c-c, p1-p1, p2-p2, m-m).
2. Arch width measurements (from study models)
c-c: Intercanine width: distance between the mandibular canine tips or between the central fossae on the surfaces in case of worn cusps
p1-p1: First inter premolar width: distance between the central fossae on the occlusal surfaces of the maxillary first premolars
p2-p2: Second inter premolar width: distance between the central fossae on occlusal surfaces of the maxillary second premolars
m-m: Intermolar width: distance between the mesial ends of the central fissures on the occlusal surfaces of the maxillary first molars
Measurement for the inter arch distances will be measured in mm using fine-pointed digital callipers. The measurements will be approximated to the first decimal place.
All measurements will be carried out by a single investigator to avoid inter-operator error. Intra-operator reliability will be assessed by repeating measurements on 10 study casts 2 weeks apart and carrying out an error analysis.
Secondary outcome measures
1. Pain perception will be recorded using a pain questionnaire, to be completed by patients following each archwire change at:
1.1. 2 hrs
1.2. 6 hrs
1.3. Bedtime on day of appointment
1.4. When they wake up the day after their appointment
1.5. When they wake up 2 days after their appointment
1.6. When they wake up 3 days after their appointment
2. Anxiety experienced will be recorded using an anxiety questionnaire, to be completed by participant at end of appointment
3. Any appliance breakages during treatment will be recorded
Overall trial start date
01/12/2011
Overall trial end date
01/12/2013
Reason abandoned (if study stopped)
Eligibility
Participant inclusion criteria
Patients:
1. Aged between 11 and 21 years of age
2. In the permanent dentition
3. Requiring upper and lower fixed appliances
4. Receiving treatment in the lower arch on a non-extraction basis
5. With mild lower arch crowding
6. All malocclusions
Participant type
Patient
Age group
Child
Gender
Both
Target number of participants
The target total recruitment of participants for the trial is 86 patients
Participant exclusion criteria
1. Impacted teeth in the lower arch
2. Hypodontia in the lower arch
3. Extractions in the lower arch
Recruitment start date
01/12/2011
Recruitment end date
01/12/2013
Locations
Countries of recruitment
United Kingdom
Trial participating centre
Queen Alexandra Hospital
Portsmouth
PO6 3LY
United Kingdom
Sponsor information
Organisation
Queen Alexandra Hospital (UK)
Sponsor details
c/o Mrs Kate Greenwood
Research and Development
Gloucester House
Cosham
Portsmouth
PO6 3LY
United Kingdom
Sponsor type
Hospital/treatment centre
Website
Funders
Funder type
Other
Funder name
Investigator initiated and funded
Alternative name(s)
Funding Body Type
Funding Body Subtype
Location
Results and Publications
Publication and dissemination plan
Not provided at time of registration
Intention to publish date
Participant level data
Not provided at time of registration
Basic results (scientific)
Publication list