Prominent (or sticking out) upper front teeth are a common problem in children around the world. For example, this condition affects about a quarter of 12-year-old children in the UK. The correction of this condition is one of the most common treatments performed by orthodontists (dentists who specialise in the growth, function and position of teeth and jaws). This condition develops when the child’s permanent teeth erupt. Children are often referred to an orthodontist, for treatment with dental braces, to reduce the prominence of the teeth. Prominent upper front teeth are more likely to be injured and their appearance can cause significant distress. If a child is referred at a young age, the orthodontist is faced with the dilemma of whether to treat the patient early or to wait until the child is older and provide treatment in adolescence.
In ‘early treatment’, treatment is given in two phases: first at an early age (seven to 11 years old) and again in adolescence (around 12 to 16 years old). In ‘late treatment’ (one phase), there is only one course of treatment in adolescence.
As well as the timing of treatment, this review also looked at the different types of braces used: removable, fixed, functional, or head-braces.
What was the research?
A systematic review to assess the effects of orthodontic treatment for prominent upper front teeth in children. The review looks at whether this treatment is best initiated at seven to 11 years old (early treatment in two phases), or in adolescence, at around age 12 to 16 years (late treatment in one phase). The use of different types of braces was also assessed.
Who conducted the research?
The research was conducted by a team led by Klaus B.S.L. Batista of Rio de Janeiro State University on behalf of Cochrane Oral Health. Badri Thiruvenkatachari, Jayne E. Harrison and Kevin D. O’Brien were also on the team.
What evidence was included in the review?
We included 27 randomised controlled trials, including 1,251 participants. Participants were children and adolescents aged under 16 years who had prominent upper front teeth (Class II Division 1 malocclusion). The evidence in this review is up to date as of 27 September 2017.
What did the evidence say?
The evidence suggests that providing orthodontic early treatment to children with prominent upper front teeth reduces the incidence of damage to upper incisor teeth significantly (middle four teeth at the top) as compared to treatment that is provided in one phase in adolescence. There are no other advantages of providing a two-phase treatment (i.e. between age seven to 11 years and again in adolescence) compared to treatment in one phase in adolescence.
The evidence also suggests that providing treatment with functional appliances for adolescents with prominent upper front teeth, significantly reduces their prominence when compared to adolescents who did not receive any treatment. The studies did not suggest that any particular appliance was better than any other for reducing teeth prominence.
How good was the evidence?
The overall quality of the evidence is low for most comparisons and outcomes, therefore further research is needed and may change the findings.
What are the implications for dentists and the general public?
Orthodontic treatment for children, followed by a later phase of treatment when in adolescence, may significantly reduce the incidence of incisal trauma as compared to treatment that is provided in one phase in adolescence. There seem to be no other advantages for providing a two-phase treatment in children compared to one-phase in adolescence.
Orthodontic treatment with functional appliances in adolescents with prominent upper front teeth appears to significantly reduce the protrusion of the upper teeth when compared to adolescents who are not treated.
What should researchers look at in the future?
More research is needed. Consideration needs to be given to forming a consensus on the type of outcome measures that are used in orthodontic trials; this is particularly relevant for cephalometric measurement and analysis. In addition, studies should be carried out at the same time points and reported according to the Consolidated Standards of Reporting Trials (CONSORT) guidelines. Moreover, intention-to-treat analysis should be carried out properly, since attrition bias was the most common risk of bias in this review: it was considered ‘high risk’ in 8 of the 27 studies.
Batista KBSL, Thiruvenkatachari B, Harrison JE, O’Brien KD. Orthodontic treatment for prominent upper front teeth (Class II malocclusion) in children and adolescents. Cochrane Database of Systematic Reviews 2018, Issue 3. Art. No.: CD003452. DOI: 10.1002/14651858.CD003452.pub4.
This post is an extended version of the review’s plain language summary, compiled by Anne Littlewood at the Cochrane Oral Health Editorial Base.