When an orthodontist talks about your “bite,” they mean the way your upper and lower teeth come together when you close your mouth. When teeth or jaws are out of line, that balance changes, and the effects can show up in how you chew, speak, and care for your teeth.
This guide explains the most common bite problems in plain language, what can cause them, and how each one may affect everyday function.
What Orthodontists Mean by a “Bad Bite”
The clinical term for a bad bite is malocclusion. It simply means the teeth meet in an irregular way or do not meet at all. A malocclusion can involve the teeth, the jaws, or both, and many people have more than one type at the same time.
What Causes Bite Problems?
Bite problems often run in families. Childhood habits and conditions can also play a role, including long-term thumb sucking, extended pacifier or bottle use, jaw injuries, and cleft lip or palate, according to the American Association of Orthodontists.
Overbite (Deep Bite)
A small amount of overlap between the upper and lower front teeth is normal. An overbite, also called a deep bite, occurs when the upper front teeth cover too much of the lower front teeth vertically. In more pronounced cases, the lower teeth may bite into the gums behind the upper teeth.
How it can affect function: A deep bite can lead to extra wear on the teeth and may contribute to gum irritation and jaw discomfort over time.
Overjet (Protruding Front Teeth)
People often confuse overjet with overbite. The difference is direction. Overjet describes upper front teeth that stick out too far horizontally past the lower teeth, while overbite describes too much vertical overlap. Overjet is sometimes called protrusion or “buck teeth.”
How it can affect function: Protruding upper teeth are more exposed to chips and breaks during falls or sports. Some people also find it harder to close their lips comfortably over the teeth.
Underbite
An underbite occurs when the lower jaw sits forward, so the lower front teeth rest in front of the upper front teeth. Underbites are often related to differences in how the upper and lower jaws grow.
How it can affect function: An underbite can make biting and chewing more difficult, affect certain speech sounds, and increase wear on the teeth. The added stress on the jaw joints may also lead to discomfort.
Crossbite
In a healthy bite, the upper teeth sit slightly outside the lower teeth. A crossbite happens when some upper teeth sit inside the lower teeth instead. It can affect one tooth or a group of teeth:
- Posterior crossbite: Upper back teeth fall inside the lower back teeth. This is the more common type and is often linked to a narrow upper jaw.
- Anterior crossbite: One or more upper front teeth sit behind the lower front teeth.
How it can affect function: A crossbite can cause the jaw to shift to one side when closing. In growing children, that shift may contribute to uneven jaw growth. Crossbites can also wear down enamel.
Open Bite
An open bite means some upper and lower teeth do not touch when the mouth is closed.
- Anterior open bite: The back teeth meet, but the front teeth do not overlap. Thumb sucking, tongue position, and mouth breathing during early development can contribute.
- Posterior open bite: The front teeth meet, but the back teeth do not.
How it can affect function: Open bites can make it harder to bite into foods with the front teeth and may affect swallowing and speech. With an anterior open bite, the back teeth take on more of the chewing load.
Bite Problems at a Glance
| Bite Problem | What It Looks Like | Common Functional Effects |
| Overbite | Upper front teeth cover too much of the lower front teeth | Tooth wear, gum irritation |
| Overjet | Upper front teeth stick out past the lower teeth | Higher risk of injury to front teeth, lip closure difficulty |
| Underbite | Lower front teeth sit in front of the upper teeth | Chewing and speech difficulty, tooth wear |
| Crossbite | Upper teeth sit inside the lower teeth | Jaw shifting, enamel wear |
| Open bite | Teeth do not touch when the mouth is closed | Biting, swallowing, and speech difficulty |
Why Bite Problems Are Worth Evaluating
Misaligned teeth left untreated may lead to decay and gum disease, along with enamel wear and difficulty chewing. In children, bite problems are unlikely to correct themselves and often become more noticeable as growth continues, which is one reason timing matters. Families with younger children can learn how we approach growing smiles on our page about children’s orthodontics.
Bite problems often overlap with spacing issues, and our guide to crowded teeth and gaps covers that side of the picture. For a broader look at why patients pursue treatment, see our overview of the benefits of orthodontics.
How Orthodontists Approach Bite Correction
Treatment depends on which bite problem is present, how severe it is, whether the cause is dental or skeletal, and the patient’s age. Common tools include braces, clear aligners, elastics, and expanders for a narrow upper jaw. Our guide to types of braces compares the options available at our office, and our blog explains how metal braces work to guide the bite into better alignment.
Some cases involving significant jaw differences in adults may call for coordination with an oral surgeon. Only an in-person evaluation can determine which approach fits your situation.
Get Your Bite Evaluated
If any of these patterns sound familiar, a Birmingham orthodontist can examine your bite and explain what, if anything, needs attention. The first visit at Backus Smiles is complimentary. Call (659) 734-1740 or contact our office to schedule.