Functional Appliances | Old Street, City Road & Enfield

Guiding Jaw Growth in Growing Children and Teenagers

Functional appliances are removable devices used in orthodontics to help guide the growth and position of the jaws, rather than just moving individual teeth. They’re most commonly used to help correct an underdeveloped lower jaw and rely on a child’s natural growth, so timing is an important part of whether this treatment is suitable.

At Dental Arts Studio in City Road and Enfield, London, our dentists assess your child’s teeth, bite, and stage of growth to confirm whether a functional appliance is a suitable and well-timed option.

Considering Functional Appliances for Your Child?

0207 250 3536 (City Road) | 0208 362 3110 (Enfield)

What Are Functional Appliances?

Functional appliances are removable devices, usually worn in the mouth, that use the natural forces of biting, swallowing, and jaw muscle activity to influence how the jaws grow relative to each other. Unlike braces, which mainly move individual teeth, functional appliances aim to correct the underlying position and growth of the jaw itself.

Functional appliances are most commonly used to help with:

An underdeveloped or set-back lower jaw (a significant overbite)
Certain other jaw growth discrepancies identified during an orthodontic assessment
Preparing the bite ahead of further orthodontic treatment, such as fixed braces

Because they work with a child’s natural growth, functional appliances are only effective during specific stages of growth and development. Your dentist will assess whether your child is at a suitable stage for this type of treatment.

Is a Functional Appliance Right for Your Child?

A functional appliance may be considered if your child:

Has a noticeably underdeveloped or receding lower jaw
Has been assessed as being at a suitable stage of growth for this type of treatment
Is likely to be able to wear a removable appliance consistently, as instructed
May benefit from addressing jaw growth before considering fixed braces

Functional appliances are used in growing children and adolescents, as they rely on natural jaw growth to work; this type of treatment isn’t relevant once growth is complete. An orthodontic assessment will confirm whether this is a suitable option, and at what stage, for your child.

Types of Functional Appliances

Twin block appliances

One of the most commonly used designs, consisting of upper and lower removable plates that interlock to guide the lower jaw into a more forward position while your child bites together.

Other functional appliance designs

Several other designs exist, each suited to slightly different jaw and bite patterns. Your dentist will recommend the type most appropriate for your child’s specific assessment.

Before Starting Treatment

Orthodontic assessment

Your dentist examines your child’s teeth, jaw, and bite, often supported by X-rays, photographs, and impressions or scans, to assess whether a functional appliance is appropriate and well-timed.

Discussing timing and commitment

Your dentist will explain why the timing of treatment matters, and what’s involved in terms of wearing the appliance consistently for it to work.

Treatment planning

You’ll be given a written treatment plan setting out the expected treatment time and cost before treatment begins.

The Functional Appliance Treatment Process

Step 1: Assessment and planning

Records such as X-rays, photographs, and impressions or scans are used to assess your child’s growth pattern and plan the appliance design.

Step 2: Fitting the appliance

The custom-made appliance is fitted, and your dentist explains how many hours a day it needs to be worn.

Step 3: Wearing the appliance

Your child wears the appliance as instructed, generally including overnight wear, removing it for eating and cleaning.

Step 4: Regular review appointments

Your dentist monitors your child’s jaw growth and bite at regular intervals, adjusting the appliance as needed.

Step 5: Moving on to further treatment

Once the jaw relationship has improved as planned, further orthodontic treatment, such as fixed braces, may be recommended to align the individual teeth.

Benefits of Functional Appliances

For suitable, well-timed cases, functional appliances may help:

Improve the relationship between the upper and lower jaw during growth
Address certain bite issues in a way that’s only possible while a child is still growing
Help simplify or shorten a later course of fixed brace treatment, in some cases

Results depend heavily on the appliance being worn consistently as instructed and on your child’s individual growth pattern, which can vary. Your dentist will discuss what’s realistically achievable based on your child’s assessment.

Cost of Functional Appliance Treatment

The cost of functional appliance treatment depends on the type of appliance used and the overall treatment plan, including whether further orthodontic treatment is likely to follow.

Treatment fees

We provide a written treatment plan with clear costs before any treatment begins, so you can make an informed decision without pressure.

Payment and finance

[Finance options](https://www.dentalartsstudio.co.uk/dental-finance/) may be available to help spread the cost of treatment — please ask our team for details.

Want to Discuss Your Child’s Orthodontic Needs?

0207 250 3536 | 0208 362 3110

Helping Your Child Get the Most from Treatment

A functional appliance works best with consistent wear and good habits at home.

Encourage consistent wear — The appliance needs to be worn for the recommended number of hours, including overnight, to be effective.
Support good oral hygiene — The appliance and teeth should be cleaned each day thoroughly.
Attend all review appointments — Regular monitoring allows your dentist to track growth and adjust the appliance as needed.
Store the appliance safely when not worn — A protective case helps prevent loss or damage.
Contact us with any concerns — If the appliance causes ongoing discomfort or doesn’t seem to fit well, let us know rather than waiting for the next appointment.

Frequently Asked Questions

What age is suitable for a functional appliance?

This depends on your child’s individual growth pattern rather than age alone, though it’s typically considered during the pre-teen to early teenage years. Your dentist will assess growth and development to identify a suitable time.

Are functional appliances suitable for adults?

No, functional appliances rely on natural jaw growth to work, so they aren’t used once a person’s jaw growth is complete. Adults with jaw discrepancies may be offered different treatment options, which your dentist can discuss.

Does my child need to wear the appliance all the time?

Most functional appliances need to be worn for a significant number of hours each day, often including overnight, to be effective. Your dentist will explain the specific wear time needed.

Will my child still need braces afterwards?

Often, yes. Functional appliances address the position of the jaws, and fixed braces may still be needed afterwards to align the individual teeth precisely.

Is the appliance uncomfortable to wear?

Some initial adjustment, including mild discomfort or increased saliva, is common in the first few days. This generally settles down as your child gets used to wearing it.

What happens if my child doesn’t wear the appliance as instructed?

Functional appliance treatment relies on consistent wear to work effectively. If it’s not worn as advised, treatment may take longer or not achieve the intended result, which your dentist can discuss further if this becomes a concern.

How much does functional appliance treatment cost?

Costs depend on the type of appliance used and the overall treatment plan, including any further orthodontic treatment likely to follow. We provide a detailed, written quote after your assessment so you know the costs involved.

Ready to Discuss Your Child’s Orthodontic Care? Book a Consultation

Book a consultation with our team to find out whether a functional appliance is a suitable and well-timed option for your child, and what to expect from the process.

We know it’s not always easy to get to a dentist during the working week, so as well as routine private dentist care, we offer Saturday and late night appointments in Enfield, and same day dental appointments for patients from City Road and Old Street, including corporate and lunchtime checkup bookings.

Speak to Our Team