Bite Problems: Overbite, Underbite, Open Bite and Crowding
This page is general information and does not replace an examination.
Bite problems (malocclusion) are teeth or jaws that do not meet as they should: an overbite, an underbite, an open bite, a crossbite, or crowded and crooked teeth. A review of 77 studies estimated that 56% of children and adolescents worldwide have some form of malocclusion[1]. Not every bite problem needs treatment. At Ulubey Dental Clinic in Antalya we examine the bite, take a panoramic X-ray, and treat with fixed braces or Invisalign clear aligners when treatment is worthwhile.
What a bite problem (malocclusion) is
Your “bite” is the way your upper and lower teeth meet when you close your mouth. In an ideal bite, the upper front teeth sit slightly in front of and over the lower front teeth, the back teeth interlock, and the teeth stand in an even arch. Malocclusion is the dental term for any clear departure from this: teeth that are crowded, rotated or spaced, or jaws that are out of line with each other.
Malocclusion is very common. A 2020 meta-analysis of 77 studies estimated a worldwide prevalence of 56% in children and adolescents, with a very wide range between studies (95% confidence interval 11–99%), and found that most bite traits did not change much between the baby-tooth and adult-tooth stages, while crowding became more common and crossbite less common[1]. Being common does not make every bite problem a disease: many mild ones never need treatment.
Dentists often describe the relationship of the back teeth in three classes. In Class I the jaws meet normally but individual teeth are crowded or spaced; in Class II the lower teeth sit too far back relative to the upper teeth (often seen as protruding upper front teeth); in Class III the lower teeth sit too far forward (an underbite). Short definitions of these and other terms are in our dental glossary.
Types of bite problems
Most people with a bite problem have more than one of the features below. The table describes them in plain terms; which ones you have is decided at an examination, not from a photo.
| Type | What it looks like | What it can lead to |
|---|---|---|
| Overbite (deep bite) | The upper front teeth overlap the lower front teeth too far vertically | Tooth wear; in some cases restorative work is later needed[11] |
| Protruding upper front teeth (increased overjet) | The upper front teeth stick out in front of the lower teeth | A higher risk of injury to the front teeth, which is why early treatment is considered in children[6] |
| Underbite | The lower front teeth sit in front of the upper front teeth | Effects on chewing, speech, jaw comfort and tooth wear[11] |
| Open bite | A gap between the upper and lower front teeth when the back teeth are closed | Effects on chewing, speech and appearance[11] |
| Crossbite | Some upper teeth bite inside the lower teeth, at the front or the side | Cheek biting; a sign that the upper and lower jaw widths do not match[4] |
| Crowding | Not enough space, so teeth overlap or twist | Areas that are hard to clean, chewing or speaking problems[11] |
| Spacing | Gaps between the teeth | Mostly appearance; a new or widening gap in an adult should be checked; see gaps between teeth |
This table is general information to help you understand the terms; it does not replace an examination.
What causes bite problems
Most bite problems come from a combination of factors rather than one cause:
- Jaw size and shape. The size and position of the jaws are largely inherited. When the jaw has too little room for all the adult teeth, they crowd or overlap[11]; when the upper and lower jaws grow at different rates, the result can be a Class II or Class III bite.
- Childhood sucking habits. A 2026 meta-analysis of 12 studies found that both thumb or finger sucking and dummy (pacifier) use increased the risk of an open bite and a crossbite in children; dummy use carried the higher risk for crossbite[5].
- Tongue position and other habits. Pushing the tongue against the teeth when swallowing (tongue thrust) is one of the reported causes of protruding front teeth[4].
- Early or late loss of baby teeth. Losing baby teeth too early or too late can disturb the position of the adult teeth that replace them[4].
- Missing teeth and gum disease in adults. Teeth can drift into gaps, and teeth weakened by gum disease can fan out or move[4][11]. Ways to fill a gap are explained in dental bridges and dental implants.
When a bite problem is worth treating
Treatment is not automatic. The NHS describes braces as useful when teeth are crowded or stick out, when the jaws do not meet properly, when there are large gaps, or when the position of the teeth makes it hard to chew or keep the teeth clean[2]. Appearance is also a valid reason, as long as you know what the treatment involves and how long it takes.
- You often bite your cheek or the roof of your mouth[4].
- Chewing or biting into food is difficult or uncomfortable[4].
- Some teeth are wearing down faster than others; see tooth wear.
- Crowded teeth are hard to clean, or your gums bleed around them.
- A child’s upper front teeth stick out noticeably, or a gap appears between the front teeth when the back teeth are closed.
- Your teeth have started to move or fan out as an adult.
In children with protruding upper front teeth, a Cochrane review of 27 randomised trials found that early treatment with a functional appliance reduced new injuries to the front teeth compared with treatment started in adolescence (odds ratio 0.56; moderate-quality evidence), but gave no other clear advantage in the final result[6]. That is why timing in children is an individual decision. We treat children from about age 5–6, if the child cooperates; Dr. Surur Ulubey treats our child patients. More on this is in our children’s dentist guide.
Jaw pain is a separate question: a bite problem is only one of many possible factors, and pain should be examined before anything is changed. See jaw pain and TMJ problems and teeth grinding.
Treatment options
Orthodontic treatment moves the teeth themselves through the bone, slowly and with light forces. At our clinic we use two methods: fixed braces and Invisalign® clear aligners. We do not use other aligner systems, and we do not offer ceramic or lingual (behind-the-teeth) braces.
| Option | How it works | Points to know |
|---|---|---|
| Fixed braces | Brackets are bonded to each tooth and connected with a wire that moves the teeth over time[2] | Usually 1–2 years; a check every 6–8 weeks; teeth can be sore for a few days after fitting[2] |
| Invisalign clear aligners | A series of thin, clear plastic trays, each worn for about a week, moves the teeth step by step[3] | Worn at least 22 hours a day and taken out to eat, drink and brush[3]; well suited to mild to moderate problems, less predictable in severe cases[10] |
| Braces combined with jaw surgery | For a jaw-size or jaw-position problem that tooth movement alone cannot correct in an adult[7] | A major operation done by an oral and maxillofacial surgery team, usually with a hospital stay[7] |
| Veneers or crowns | Change the visible shape of the teeth; they do not move the teeth or correct the bite | Sometimes used to disguise mild crowding; for crooked teeth, moving the teeth is usually the more conservative choice; see the honest truth about Turkey teeth |
Which option suits you depends on the type and severity of the bite problem, your gum health and your teeth; it is decided at the examination.
How braces and clear aligners compare for adults (wear time, visibility, cleaning, cost and visits) is explained in detail in our guide to braces or clear aligners for adults.
Bite problems in adults
Teeth can be moved at any age; the American Association of Orthodontists states that 1 in 3 orthodontic patients today are adults[11]. Adult treatment differs from treatment in children in three ways:
- The jaws no longer grow. In an adult, a jaw-size problem cannot be guided by growth; tooth movement can disguise a mild one, while a severe one may need surgery[7].
- Gum health comes first. In people with advanced gum disease, European guidance includes orthodontic tooth movement as one part of treatment, with the gum disease treated as its own step and re-checked during treatment[8]. Bleeding or inflamed gums are treated before any brace or aligner; see gum disease.
- Existing dental work. Dental implants are fused to the bone and cannot be moved with braces or aligners, so when both are planned, the tooth movement is usually planned first. Crowns and large fillings can also affect how brackets or aligner attachments are placed.
Keeping the result: retainers
Without a retention phase, straightened teeth tend to move back towards where they started[9]. After braces or aligners you wear a retainer: a thin wire bonded behind the front teeth (fixed) or a clear removable tray. The NHS notes that the treating dentist tells you how long to wear it[2].
The evidence on which retainer to choose is weaker than many patients expect. A 2023 Cochrane review of 47 trials with 4,377 participants rated the evidence on different retainers as low or very low certainty; in one trial, removable retainers worn part-time caused more discomfort but failed less often and were linked to slightly better gum health than fixed retainers, while in another trial removable retainers worn full-time failed more often[9]. A review of reviews also found more relapse after clear aligner treatment than after fixed braces[10]. In practice, the retainer plan is part of the treatment plan from the start, and wearing it as instructed matters as much as the treatment itself.
How we assess your bite
Dr. Ali Cem Ulubey and Dr. Surur Ulubey see every patient themselves; there are no rotating dentists. Neither holds a formal specialty title. Our assessment includes:
- Examination. We look at how the teeth meet, how the jaws move, the gums and any existing dental work.
- Panoramic X-ray. We take one for every patient, to check the roots, the bone and any missing or unerupted teeth. A 3D CBCT scan is used only when it is needed; see dental X-rays and CBCT.
- Discussion of options. We explain whether treatment is worthwhile, which method fits, roughly how long it takes and how often you would need to come in.
- Written quote. Orthodontic treatment is not on our published price list; it is priced in a written quote after the examination, valid for 30 days. The consultation and panoramic X-ray have no separate fee.
Braces need a check about every 6–8 weeks for 1–2 years[2], and aligner treatment also needs regular reviews. Treatment therefore suits people who live in or near Antalya, or who visit regularly. If you live abroad, we discuss honestly at the consultation whether the visit schedule is practical for you before anything is started.
Frequently asked questions
How common are bite problems?
There is no single answer, because studies define bite problems differently. A worldwide meta-analysis of 77 studies estimated that 56% of children and adolescents have some form of malocclusion; crowding became more common and crossbite less common from the baby-tooth to the adult-tooth stage. Many mild bite problems need no treatment.
Can an overbite be fixed without braces?
An overbite is corrected by moving teeth, so it needs braces or clear aligners; when the cause is the size or position of the jaws in an adult, jaw surgery combined with braces may be needed. Veneers or crowns can change how the front teeth look, but they do not change how the teeth meet.
Can adults fix an open bite or underbite?
Often, yes. Many open bites and mild underbites in adults can be improved with braces or clear aligners. When the problem comes from the jaws themselves, tooth movement alone may not be enough and surgery combined with braces is considered. Your examination and X-ray show which applies.
At what age should a child’s bite be checked?
We see children from about age 5 to 6, if the child cooperates, and Dr. Surur Ulubey treats our child patients. For protruding upper front teeth, a Cochrane review found that early treatment reduced injuries to the front teeth but gave no other clear advantage, so timing is decided individually.
Do I need to wear a retainer after treatment?
Yes. Without retention, straightened teeth tend to move back towards their original position. Retainers can be a thin wire bonded behind the front teeth or a clear removable tray. Your dentist tells you how long to wear it, and the retainer plan is part of the treatment plan from the start.
How much does orthodontic treatment cost at your clinic?
Orthodontic treatment is not on our published price list. It depends on the type and severity of the bite problem and the method, so it is priced in a written quote after the examination and X-ray. The quote is valid for 30 days, and the consultation and panoramic X-ray have no separate fee.
Sources
- Lombardo G, Vena F, Negri P, et al. Worldwide prevalence of malocclusion in the different stages of dentition: a systematic review and meta-analysis. Eur J Paediatr Dent. 2020;21(2):115-122. PMID 32567942. pubmed.ncbi.nlm.nih.gov/32567942
- NHS. Braces (page last reviewed 29 June 2026; accessed 26 October 2026). www.nhs.uk/tests-and-treatments/braces
- American Association of Orthodontists. Clear aligners (accessed 26 October 2026). aaoinfo.org/treatments/aligners
- American Association of Orthodontists. Common orthodontic problems (accessed 26 October 2026). aaoinfo.org/resources/common-orthodontic-problems
- Faryad A, Muwaquet Rodriguez S, Hijazi Alsadi T. The role of digit- and pacifier-sucking habits on malocclusion development in children: anterior open bite and posterior crossbite. A systematic review and meta-analysis. Dent J (Basel). 2026;14(1):55. PMID 41590179. pubmed.ncbi.nlm.nih.gov/41590179
- Batista KB, Thiruvenkatachari B, Harrison JE, O’Brien KD. Orthodontic treatment for prominent upper front teeth (Class II malocclusion) in children and adolescents. Cochrane Database Syst Rev. 2018;3:CD003452. PMID 29534303. pubmed.ncbi.nlm.nih.gov/29534303
- American Association of Orthodontists. Orthodontic surgery (accessed 26 October 2026). aaoinfo.org/treatments/orthodontic-surgery
- Herrera D, Sanz M, Kebschull M, et al. Treatment of stage IV periodontitis: the EFP S3 level clinical practice guideline. J Clin Periodontol. 2022;49(Suppl 24):4-71. PMID 35688447. pubmed.ncbi.nlm.nih.gov/35688447
- Martin C, Littlewood SJ, Millett DT, et al. Retention procedures for stabilising tooth position after treatment with orthodontic braces. Cochrane Database Syst Rev. 2023;5:CD002283. PMID 37219527. pubmed.ncbi.nlm.nih.gov/37219527
- Yassir YA, Nabbat SA, McIntyre GT, Bearn DR. Clinical effectiveness of clear aligner treatment compared to fixed appliance treatment: an overview of systematic reviews. Clin Oral Investig. 2022;26(3):2353-2370. PMID 34993617. pubmed.ncbi.nlm.nih.gov/34993617
- American Association of Orthodontists. Adult orthodontics (accessed 26 October 2026). aaoinfo.org/adult-orthodontics
This article is general patient information and does not replace a clinical examination or X-rays.
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