Twin block braces: what they are and how they work
Twin block braces are a pair of removable plastic appliances, one for the upper teeth and one for the lower, that work together to correct an overbite in a growing child. The overbite, known to orthodontists as a Class II division 1 relationship, means the upper front teeth stick out well past the lower ones, often because the lower jaw sits further back than it should. Each appliance has a small angled block of acrylic. When the child bites together, the blocks meet and guide the lower jaw forward into a better position. Over months, the muscles and the growing jaw adapt to that new posture.
Unlike fixed braces glued to the teeth, twin blocks can be taken out for cleaning and sport. They are a functional appliance, which means they use the child's own growth and jaw muscles and not just tooth movement. This guide explains how the appliance works, what the evidence says, who it suits, how long it is worn, what it costs in Turkey compared with the UK, US and Germany, and how it fits with later treatment.
How do twin block braces correct an overbite?
The upper plate carries clasps and a screw or springs for dental expansion if needed, and a bite block that sits on the back teeth. The lower plate has a matching block with a steep slope. Because the slopes slide against each other, the child cannot close down into the old back position and is guided to bite with the lower jaw slightly forward. Held in that position for most of the day, the jaw joint and the muscles around it remodel, the lower jaw can grow more forward and the overbite reduces. The back teeth are also free to erupt downward in some cases, which helps open the bite.
The appliance is worn full time, including at meals in the first period, with removal only for brushing, sport and special occasions. Fit is checked every four to six weeks, and the blocks may be trimmed to let the back teeth move into place. After the overbite is corrected the child usually wears a retainer or a different appliance to hold the result.
Do twin block braces work? What the evidence says
Research, including systematic reviews, shows that functional appliances such as the twin block can reduce an overbite in children treated during growth, mostly by a mixture of lower jaw growth and tooth movement. The NHS describes this method as a treatment for children whose jaws are still growing. The evidence is more cautious in one respect: the extra growth of the lower jaw appears modest and partly dental, so it does not turn a very small jaw into a large one, and results differ from child to child. Twin blocks work best when the child cooperates by wearing them as instructed, which is the single most important factor.
Starting at the right moment, usually around the growth spurt, improves the chance of a good outcome. For a child whose growth is finished, appliances like this are not effective and other approaches are considered.
Who are twin block braces for, and who is not a good candidate?
The typical patient is a child of about 9 to 14 with an overbite, upper teeth that stand forward, a lower jaw that sits back and some growth left. Early assessment is useful because an overbite increases the risk of injury to protruding front teeth. Twin blocks are usually not suitable if the child will not wear a removable appliance, if the overbite is mostly caused by a skeletal problem that is too large to be changed by growth modification, or if the upper arch is crowded in a way that needs fixed braces first. Adults with a skeletal overbite are generally treated with fixed appliances or with jaw surgery, as described in our guide to orthodontics in Turkey.
What to expect in the first weeks of wear
- Days 1 to 3: the plates feel bulky, speech is affected and there is extra saliva. This is normal and usually settles within a week or two.
- Week 1 to 2: soreness of the cheeks, gums or teeth is common. Eat soft food and keep the plates in for as long as is comfortable; wearing them is what makes them quicker to get used to.
- Weeks 2 to 6: speech returns to normal, and the child is asked to wear them more or less full time.
- Months 2 to 9: checks every four to six weeks, trimming or adjustments, and the overbite starts to reduce.
Brushing the appliance and the teeth after every meal protects the teeth against decay. Plates should be kept in a case when out of the mouth, because lost or broken appliances are a common cause of delays.
Twin block braces cost in Turkey compared with the UK, US and Germany
These are approximate ranges for the twin block phase, not hospital quotes. The price depends on the clinic, the number of appliance replacements, whether records such as X-rays and photographs are included, and whether a second phase of fixed braces follows.
| Country | Approximate cost range |
|---|---|
| Turkey | €500 – €1,800 |
| United Kingdom | €1,500 – €4,000 |
| United States | €1,800 – €5,000 |
| Germany | €1,200 – €3,500 |
Many UK children are treated under the NHS, so private figures apply mainly to families who choose private care. A price for twin blocks normally covers the examination, records, the appliances and the review visits, but not later fixed braces. Ask for the phases to be itemised in writing.
Twin blocks, fixed braces or clear aligners?
These approaches are not strictly alternatives, because they act in different ways and are sometimes used in sequence. Twin blocks modify jaw relationship while the child grows. Fixed braces then align the teeth precisely. Clear aligners such as Invisalign are mainly used for teeth alignment, and variants for teenagers exist, but they do not replace a functional appliance in a child whose main problem is jaw position.
| Treatment | Best suited to | Typical limits |
|---|---|---|
| Twin block braces | Growing children with an overbite and a retruded lower jaw | Needs full-time wear; little effect after growth ends |
| Fixed braces | Aligning teeth, closing gaps, finishing the bite | Cannot be removed; diet and cleaning need care |
| Clear aligners | Mild to moderate tooth alignment, older teenagers and adults | Less suited to correcting jaw position |
Before and after: what are realistic results?
A typical before and after photo set shows the upper front teeth sitting closer to the lower ones, a better profile as the chin appears more forward, and a bite that closes more evenly. The change is usually seen over six to twelve months of active wear. What the photos do not show is the next phase. Many children still need fixed braces for some months afterwards to align crowded or rotated teeth, and a retainer to hold the result. Results depend strongly on how consistently the child wears the plates and on growth, so ask for examples of children of a similar age and overbite, not only the most dramatic cases.
Can twin block treatment be done on a trip to Turkey?
This is the practical difficulty. The twin block is not a one-visit treatment: it needs a fitting, a series of reviews every four to six weeks and a period of about nine to twelve months, followed by retention. A family living abroad can usually do the assessment, records and the fitting during a trip, but the reviews must be done by a local orthodontist who is willing to continue the treatment. Agree this in writing before you start, including who will adjust the appliances and who is responsible if something breaks. A short visit to Turkey suits an assessment, a second opinion or a case where the treatment is planned to be completed within a series of planned visits.
Risks and side effects of twin block braces
The appliance is generally safe, but it has drawbacks. Temporary speech changes, extra saliva, sore cheeks and gums are common early on. Poor cleaning can lead to decay and gum inflammation, so brushing after meals is essential. Plates can be lost or broken, which delays treatment. Occasionally the lower front teeth tilt forward, and treatment may relapse if the retainer is not worn. Professional bodies such as the British Orthodontic Society advise that orthodontic treatment is provided by a registered specialist and that the family understands the length of treatment and the commitment before it begins.
How to choose an orthodontist for twin block braces, and red flags
Look for a registered orthodontic specialist, a clinic that takes X-rays and photographs and shows you the treatment plan, and one that explains the length of treatment and the retainer phase. Red flags include promising a result in a few weeks, offering twin blocks to an adult without discussing alternatives, a quote with no mention of follow-up and no plan for the phase after the appliance. Read how our process works and see all dental treatments in Turkey.
- Is my child at the right stage of growth for a twin block, and how will you check?
- How many months of full-time wear are expected and what happens if the plates are lost?
- Will fixed braces be needed afterwards, and is that phase in the quote?
- Who will carry out the monthly reviews if we live abroad?
- What retainers are provided and for how long must they be worn?
Send your child's photographs and X-rays through the free quote page for a written plan.
Hospitals with Dental Treatments in Turkey
Frequently asked questions
They are a pair of removable plastic appliances, one for the upper and one for the lower teeth, that guide the lower jaw forward in a growing child. They are used to correct an overbite.
Studies show they can reduce an overbite in children treated during growth, through a mix of jaw growth and tooth movement. Results vary with timing and, above all, with how consistently the child wears them.
Approximate ranges are €500 to €1,800 in Turkey, against about €1,500 to €4,000 for private care in the UK. The price depends on records, review visits and any later fixed braces. A clinic confirms its price in writing.
Active treatment usually lasts about nine to twelve months, with the plates worn almost full time. A retainer or further appliance often follows to hold the result.
They are usually used between about 9 and 14, around the growth spurt, when the jaw is still growing. Your orthodontist assesses growth from the face, teeth and X-rays.
They cause soreness of the teeth, cheeks and gums and a lisp in the first one to two weeks. This usually settles as the child gets used to them, and soft food helps.
They do different jobs. Twin blocks change the jaw relationship in a growing child, while fixed braces align the teeth. Many children have twin blocks first and fixed braces afterwards.
They are designed for growing children, so adults with a skeletal overbite are usually treated with fixed braces, clear aligners or, for larger problems, jaw surgery after assessment.
Treatment takes longer or fails because the appliance only works while it is in the mouth. Regular wear is essential, and a clinic should explain this before starting.
A fitting can usually be done in two to four days after records are taken. Because reviews are needed every four to six weeks, arrange a local orthodontist to continue before you start.