Key Takeaways
- Crooked teeth, or malocclusion, are common and may appear as overlapping, twisted, crowded or spaced teeth—often developing during childhood due to genetics or habits like thumb sucking.
- Common causes include jaw growth discrepancies, poor oral hygiene, malnutrition, prolonged pacifier use and inherited traits.
- Bite issues such as overbite, underbite, open bite, crossbite, overcrowding and spacing can impact both appearance and function.
- Crooked teeth can lead to health problems like difficulty cleaning teeth, gum disease, jaw pain, speech issues and uneven enamel wear if untreated.
- Treatment options include traditional braces, clear aligners, veneers (for cosmetic fixes), and in severe cases, corrective jaw surgery.
- Braces and aligners are considered most effective for aligning teeth and improving bite, while veneers are ideal for minor cosmetic corrections.
- Early dental visits and preventive care—including interceptive orthodontics—can help manage or prevent crooked teeth in children.
- See a dentist for mild cases or general oral health concerns; consult an orthodontist for severe misalignment, bite problems or jaw discomfort.
Also known as dental misalignment or malocclusion, crooked teeth refer to teeth that are not properly aligned within the mouth. They may appear twisted, crowded, overlapping or spaced too far apart.
This condition is common in both children and adults. In many cases, crooked teeth begin to develop during childhood as permanent teeth grow in. Factors such as genetics, thumb-sucking, prolonged use of a pacifier or early loss of baby teeth can all influence the way teeth come in. In adults, teeth can shift over time due to ageing, tooth loss or habits like teeth grinding and poor oral hygiene.
While some people are perfectly comfortable with the natural look of their smile, others may experience improper bite alignment, difficulty maintaining oral hygiene and increased risk of dental complications.
In this article, we will explore five common causes of crooked teeth, their types, treatment options and more.
What Causes Crooked Teeth?
According to Scientific American, nine out of ten people have slightly misaligned teeth. While mild misalignment is common and often harmless, more pronounced cases can lead to complications if left untreated. Several factors contribute to the development of crooked teeth, many of which begin in early childhood. Understanding these causes can help determine the most effective course of treatment.
Genetics
Just as we inherit our eye colour and height, the shape and size of our jaws and teeth are also passed down through generations. If one or both of your parents had crooked teeth, there is a higher chance that you might develop them too.
Some people may inherit a small jaw and large teeth, leading to crowding, while others may have spacing issues due to having a larger jaw and smaller teeth.
Thumb Sucking
Thumb sucking is a natural reflex for babies and young children. When they suck their thumbs, they get comfort and a sense of security, especially during stressful situations or while falling asleep.
However, if the habit continues beyond the toddler years, it can interfere with normal oral development. It puts constant pressure on the roof of the mouth (palate) and can slowly change its shape.
In fact, a study from the American Academy of Pediatric Dentistry found that prolonged thumb sucking can increase the risk of developing malocclusions like anterior open bite (where the front teeth don’t meet) and Class II molar relationships (where the upper back teeth are too far forward compared to the lower teeth). This is particularly true when it extends beyond age 4 or persists for five years or longer.
Poor Oral Hygiene
Failing to care for your oral health increases the danger of cavities, gum disease and tooth loss, which in turn can contribute to teeth shifting out of place.
For instance, tooth decay and untreated cavities can weaken the structural integrity of a tooth. In severe cases, decayed teeth may need to be extracted, leaving gaps behind. When this happens, the neighbouring teeth can begin to shift into the empty space, disrupting the natural alignment and leading to crowding or tilting.
Malnutrition
When a child doesn’t receive enough essential nutrients such as calcium, vitamin D and phosphorus, it can affect the strength and development of both the teeth and the jawbones. Calcium and vitamin D, in particular, are important for forming strong, dense bones and teeth. A deficiency can lead to softer bones and weaker dental structures, making teeth more prone to shifting or erupting improperly.
In some cases, malnourished children may also develop habits such as mouth breathing or tongue thrusting as compensatory behaviours for other health issues (e.g., swollen tonsils or chronic respiratory infections), which can further contribute to dental misalignment.
Jaw Growth Discrepancies
When the upper and lower jaws develop at different rates or in disproportionate sizes, it can lead to crooked teeth and bite misalignment. This condition is often referred to as a jaw growth discrepancy, and it typically becomes noticeable during childhood or adolescence as the facial bones mature.
A mismatch in jaw growth doesn’t just affect how the teeth align; it can also impact facial symmetry, speech, chewing function and even breathing.
Types of Crooked Teeth Conditions
Crooked teeth come in many forms. Here are the most common types of crooked teeth conditions and how they appear.
Overbite
An overbite is when the upper front teeth excessively overlap the lower front teeth when the mouth is closed.
A slight overlap of the upper front teeth over the lower ones is normal and important for a healthy bite. However, if this overlap exceeds 2 to 4 millimetres, it’s considered an overbite. This more significant misalignment can lead to issues like jaw pain, enamel wear, and other problems with your oral health.
An overbite can sometimes be inherited as a genetic type of malocclusion, running in families. However, it may also result from certain behaviours and conditions, including:
- Grinding your teeth (bruxism)
- Habitual nail-biting
- Tongue thrusting, where the tongue moves too far forward
- Prolonged pacifier use or thumb sucking beyond age 3.
Underbite
Often due to abnormal growth of the lower jaw, an underbite occurs when the lower front teeth sit in front of the upper front teeth. It can give the mouth and face a bulldog-like appearance.
In more severe cases, the lower teeth protrude significantly forward, while in milder cases, the misalignment is subtle and may go unnoticed.
Although mild cases might be manageable for some, severe instances can result in a range of problems, including persistent jaw pain, headaches, trouble chewing and eating, tooth decay, gum disease and cavities due to misaligned teeth, speech impediments, halitosis and sleep apnea.
Open Bite
Individuals with an open bite have upper and lower teeth that do not touch when the mouth is closed. A noticeable gap remains between the upper and lower front or back teeth. This condition can affect both the appearance and function of the mouth, making it difficult to bite, chew or speak properly.
It comes in different types:
- Anterior open bite – occurs when the front upper and lower teeth don’t meet when the back teeth are closed.
- Posterior open bite – happens when the back teeth do not touch, even when the front teeth are closed together.
- Skeletal open bite – caused by abnormal jawbone growth.
- Dental open bite – caused by improper positioning of the teeth, rather than the jaw.
Crossbite
A crossbite happens when your teeth do not align correctly when your mouth is closed.
In a typical bite, the upper teeth are slightly wider and sit just outside the lower teeth. This alignment allows for an even distribution of pressure during chewing or clenching. With a crossbite, this balance is disrupted, which can lead to uneven wear, stress and potential damage to your teeth over time.
The reason a crossbite develops is usually due to a problem with the teeth themselves, the underlying bone structure or a combination of both. These issues can be triggered by habits, when teeth come in, how the jawbones are formed, difficulties with upper airway breathing or a person’s genetic makeup.
Overcrowding
Overcrowding happens when there isn’t enough space in the jaw for all the teeth to fit properly. This can lead to overlapping teeth, twisting or some teeth being pushed forward or backwards.
Crowded teeth are often caused by not having enough space in the mouth, but there are other reasons as well. Common causes include:
- A small jaw
- Teeth that are too large for the jaw
- A narrow or high palate
- Extra teeth
- Lingual habits (like thumb sucking)
- Missing or damaged teeth, which cause the remaining teeth to shift.
Spacing
Just the opposite of crowding, spacing refers to gaps between teeth. A common example is a diastema, which is a gap between the two upper front teeth. Spacing can be caused by teeth that are too small for the jaw, missing teeth or habits like tongue thrusting.
Though spacing is not always a health concern, large gaps can affect smile aesthetics and lead to food trapping and gum issues.
How Crooked Teeth Affect Your Health
While crooked teeth are mainly considered a cosmetic problem, they can cause discomfort, affect oral hygiene and lead to more serious health issues if left untreated.
Take a closer look at the potential health risks of crooked teeth to help you take steps toward correction, whether through orthodontics, dental procedures or lifestyle changes.
Difficulty in Cleaning Your Teeth
Crooked or misaligned teeth create hard-to-reach areas in your mouth, which can make brushing and flossing more difficult. The tight spaces between crowded teeth or the odd angles of rotated teeth can prevent you from cleaning all surfaces properly.
As a result, plaque and tartar may build up, leading to cavities, gum disease (gingivitis or periodontitis) and bad breath.
Speech Difficulties
Crooked teeth, especially those with severe misalignment, can affect the way you speak. Teeth that don’t align properly can alter the way air flows through the mouth. This, in turn, may cause speech impediments such as lisps or difficulty pronouncing certain sounds.
Jaw Pain and TMJ Disorder
Crooked teeth can cause your uneven bite, putting extra strain on your jaw muscles. This can lead to pain or discomfort and, over time, may develop into a condition called Temporomandibular Joint Disorder (TMJ), which affects the joint that connects your jaw to your skull.
It can cause chronic jaw pain, headaches, earaches and difficulty opening or closing your mouth. The constant strain from a misaligned bite can also lead to muscle soreness and even arthritis in the jaw joint. Severe cases may require medical intervention or surgical correction.
Excess Wear
Crowded bottom teeth may cause some teeth to stick out and constantly rub against the upper teeth. While it might not seem like a problem now, this friction can gradually wear down your enamel.
As enamel erodes from the teeth grinding against each other, it increases the risk of cavities and, in severe cases, could even lead to an abscessed tooth.
Treatment Options for Crooked Teeth
The good news is, modern dentistry offers a wide range of treatment options to align teeth and improve both aesthetics and function. The right choice for you depends on the severity of misalignment, age, budget, lifestyle and personal preferences.
Let’s explore each one:
Braces (Metal & Ceramic)
Braces are orthodontic tools made up of small brackets, bands and wires that help straighten your teeth and align your jaw. They apply gentle, consistent pressure that moves teeth into alignment over time.
There are two common types:
- Conventional braces – Also called traditional metal braces, conventional braces have metal brackets glued to your teeth, connected by a wire. Small rubber bands or metal clips hold the wire in place. Your orthodontist will adjust the braces from time to time to slowly move your teeth into the right position. Note that metal braces are quite visible when you talk or smile.
- Self-ligating braces – Self-ligating braces are similar in appearance and placement to conventional braces, but they work a bit differently. Instead of using rubber bands or metal ties, they use special clips or brackets with a spring-loaded door to hold the wire in place. These brackets keep steady pressure on the wire, which helps guide your teeth into place more smoothly over time. They can treat certain complex bite or alignment issues and may be a good option for patients with specific needs.
Who Is It Ideal For?
Braces are best for patients with moderate to severe misalignment. The treatment can help with tooth spacing, overcrowding, overbite, underbite and open bite. Make sure that you consult an orthodontist to identify which type of braces is appropriate for your situation.
Pros & Cons
| Pros | Cons |
| Can treat virtually all types of crooked teeth and bite issues. | Visible (especially metal) |
| Suitable for children and adults | May cause discomfort or sores |
| Built to withstand the full duration of your treatment and can handle the daily wear from brushing & chewing | Requires regular dental visits |
Treatment Length
On average, braces treatment takes around two years to complete, though the exact duration can vary depending on how severe the misalignment is.
Clear Aligners
Clear aligners are a series of custom-made, transparent plastic trays that fit snugly over your teeth. They offer a more discreet and often more comfortable alternative to traditional braces for many individuals.
They work by gradually applying pressure to shift your teeth, typically moving them a fraction of a millimetre at a time. Each aligner is usually worn for one week, at least 22 hours a day.
Who Is It Ideal For?
Clear aligners work best for mild to moderate misalignment. They are also ideal for patients who prefer a discreet look. Keep in mind that they may not be the best option for complex and severe orthodontic issues.
Pros & Cons
| Pros | Cons |
| Virtually invisible | May not work for severe cases |
| Allows for easy eating, drinking, brushing and flossing without any restrictions. | Can be more expensive than traditional metal braces in some cases. |
| Generally considered more comfortable than traditional braces as there are no sharp edges or wires to irritate the mouth. | Requires patient compliance & discipline to wear for enough hours |
Treatment Length
Typically 6 to 18 months. However, the total number of aligners and the length of treatment depend on your specific orthodontic concerns and how much movement is needed to achieve proper alignment.
Veneers
While veneers don’t actually move crooked teeth, they can dramatically improve their appearance by covering the front surfaces with thin, custom-made shells of porcelain or composite resin.
Your dentist will first shave a small amount of enamel off your teeth to make space for the veneers. Then, they’ll take an impression to create a model for crafting your custom veneers.
Who Is It Ideal For?
Veneers are ideal for minor misalignment or uneven teeth. They are also for patients seeking a quick aesthetic fix, and not for functional issues or severe crowding.
Pros & Cons
| Pros | Cons |
| Instant improvement in appearance | Does not actually straighten teeth |
| Long-lasting (especially porcelain); with proper aftercare, they can last for 10 to 15 years | Irreversible—removes tooth enamel |
| Can fix other cosmetic issues like chips and discolouration | Can be expensive |
Treatment Length
Usually 2–3 dental visits across a few weeks.
Jaw Surgery
Jaw surgery is used to correct misaligned, uneven or otherwise problematic jawbones. It repositions the jaws and teeth to improve function and may also enhance facial symmetry.
This type of surgery may be recommended when braces alone aren’t enough to correct a jaw issue. Your orthodontist will collaborate with a maxillofacial surgeon—an expert in surgery of the mouth, jaw and face—to develop a personalised treatment plan.
In most cases, jaw surgery isn’t recommended until jaw growth is complete, which usually happens in the late teenage years.
Who Is It Ideal For?
Jaw surgery is usually recommended for:
- Severe overbites, underbites or open bites
- Facial imbalance or jaw asymmetry
- Difficulty chewing, breathing or speaking due to jaw position
An orthodontist may only consider jaw surgery when less invasive treatments have failed or are unsuitable due to the patient’s jaw joint condition.
Pros & Cons
| Pros | Cons |
| Fixes severe bite and alignment issues | Usually paired with braces (before & after) |
| Improves daily functions such as chewing, speaking and breathing. | High cost |
| Can improve facial appearance | Involves surgery, anaesthesia and a recovery period. |
Treatment Length
The process typically takes two to three years and involves both surgery and orthodontic care.
Can Crooked Teeth Be Prevented?
Yes, crooked teeth can sometimes be prevented, especially when caught early. It begins with early and regular dental visits.
The American Academy of Pediatric Dentistry recommends that a child’s first dental visit be on their first birthday or within six months of the first tooth eruption. These early visits are not just about checking for cavities—they also help monitor your child’s jaw growth, tooth eruption and bite alignment.
Pediatric dentists can help avoid and address harmful oral habits in early childhood. This includes thumb sucking, mouth breathing and using bottles or sippy cups for too long.
You may also consider interceptive orthodontics. This treatment is generally recommended for children between the ages of 6 and 12, which helps address developing bite problems before they become more serious.
When to See a Dentist vs an Orthodontist
If you have crooked teeth, you might be wondering whether you should visit a dentist or an orthodontist. Here’s a simple guide to help you understand when to see each professional:
When to See a Dentist
Dentists are primary care providers for your oral health. If you have crooked teeth but they’re not causing major problems, you can start by seeing your dentist. Here are a few reasons to visit them:
- Routine Dental Checkups – If your teeth are crooked but not affecting your bite or causing pain, your dentist can check your oral health and give general advice. They might suggest treatments like cleanings or simple cosmetic options if needed.
- Minor Misalignment – For slight crowding or crookedness, your dentist might recommend clear aligners or other less invasive treatments to improve your smile.
- Cavities and Gum Disease – Before pursuing orthodontic treatments, you have to make sure that your teeth are healthy. If you have any cavities, gum disease or other oral health issues, your dentist will need to treat these first.
- Referral to an Orthodontist – If your dentist believes that your misalignment requires more specialised care, they will refer you to an orthodontist who specialises in teeth alignment.
When to See an Orthodontist
Orthodontists are specialists who focus on correcting misaligned teeth and bite issues. Here’s when you should see one:
- Severe Crooked Teeth – If your teeth are seriously crooked or overlapping, an orthodontist can help with treatments like braces or clear aligners to straighten them out.
- Bite Problems – If your crooked teeth are accompanied by bite issues, such as an overbite, underbite, crossbite, or open bite, an orthodontist is trained to correct these problems. An orthodontist will determine the best course of action to fix both the alignment of your teeth and your bite.
- Jaw Pain or Misalignment – An orthodontist can assess how your teeth and jaw work together, diagnosing problems like temporomandibular joint disorder (TMJ) or misalignment that could be causing pain. Treatments like braces can help correct these misalignments and relieve discomfort.
Final Thoughts
You may have learned to hide your teeth when you smile, keeping your lips a little more closed than you’d like. Perhaps out of habit, insecurity or years of feeling self-conscious about crooked teeth.
And for some of you, crooked teeth have caused jaw pain, gum disease and difficulty with day-to-day functions like chewing, breathing and speaking.
You don’t have to live the rest of your life with crooked teeth. Consulting a dental professional is the first step in determining the most suitable treatment for your unique needs. Whether it’s braces, aligners or other orthodontic solutions, a dentist or orthodontist will evaluate your oral health and create a personalised plan to straighten your teeth and improve your smile.
At The Dental Co, we are here for you. Our friendly team is ready to walk you through every step of the journey, from your first consultation to your final appointment. We offer a range of treatments, including:
- General Dentistry: Dental filling, teeth scaling & polishing and tooth extraction
- Cosmetic dentistry: Dental bleaching, dental dentures, dental crown and bridge, dental bonding and veneer
- Dental surgery: Root canal treatment, wisdom tooth removal surgery, tongue tie surgery and dental implants
- Orthodontic or dental braces: Metal braces, ceramic braces, self-ligating braces, clear aligners and retainer
Our team will examine your teeth, explain your options and recommend the best course of action. Schedule a consultation today.
