Overjet and overbite both describe how the upper and lower front teeth relate to each other, but they measure different things: overjet is the horizontal distance the upper front teeth stick out past the lower front teeth, while overbite is the vertical amount the upper front teeth overlap the lower front teeth when biting down. Both a normal bite and a bite that needs treatment can have some degree of each — a small amount of overjet and overbite is actually typical and healthy. Problems arise when either measurement is more pronounced than normal.
What Is Overjet?
Overjet refers to the horizontal (front-to-back) gap between the edges of the upper and lower front teeth. A small amount of overjet is completely normal — most healthy bites have the upper front teeth positioned slightly ahead of the lower ones. Excessive overjet, sometimes described by patients as "buck teeth," means that horizontal distance is significantly larger than normal, which can affect appearance, lip closure, and in some cases increase the risk of injury to the front teeth.
What Is Overbite?
Overbite refers to the vertical overlap between the upper and lower front teeth when the back teeth are together. Like overjet, some overbite is normal and expected in a healthy bite. A deep or excessive overbite means the upper front teeth cover a larger-than-normal portion of the lower front teeth, which in more significant cases can lead to the lower front teeth contacting the gum tissue behind the upper teeth, causing wear or irritation over time.
| Overjet | Overbite | |
|---|---|---|
| Direction measured | Horizontal (front-to-back) | Vertical (up-and-down overlap) |
| What excess looks like | Upper front teeth protrude noticeably past lower teeth | Upper front teeth cover most or all of the lower front teeth |
| Common associated concern | Lip closure, injury risk to protruding teeth | Lower teeth contacting gum tissue, uneven wear |
Can You Have One Without the Other?
Yes. It's possible to have significant overjet with relatively normal overbite, significant overbite with relatively normal overjet, or a notable degree of both at the same time. Because the two measurements capture different dimensions of the bite, an orthodontist evaluates them independently, even though they're often discussed together since both involve the relationship between the upper and lower front teeth.
How Orthodontists Measure Overjet and Overbite
Both measurements are typically assessed during a clinical exam and confirmed with digital scans and X-rays that show the precise relationship between the upper and lower teeth and jaws. This imaging helps determine not just how much overjet or overbite is present, but whether the underlying cause is dental (the teeth themselves are positioned incorrectly) or skeletal (the jawbones are mismatched), since that distinction affects the recommended treatment approach.
How Excess Overjet or Overbite Is Treated
Mild to moderate cases of either are commonly corrected with braces or clear aligners, which reposition the front teeth into a healthier relationship. More significant cases, particularly those tied to a skeletal jaw discrepancy rather than tooth position alone, may involve growth-guiding appliances in a growing child or, in adulthood, a combined orthodontic and surgical approach for cases severe enough to need it.
Why the Distinction Matters for Treatment Planning
Understanding whether a patient has excess overjet, excess overbite, or both helps our orthodontists choose the most effective appliances and treatment approach. A plan built around correcting overjet might emphasize different tooth movements than one built around correcting a deep overbite, even though both may ultimately involve braces or aligners. At Davis & Goldberg Orthodontics, we identify and measure both independently during your evaluation so your treatment plan is built around what your bite specifically needs.
Common Terms People Use for Overjet and Overbite
Patients often use everyday language that doesn't map perfectly onto these clinical terms, which can add to the confusion. "Buck teeth" usually refers to excess overjet, while a "deep bite" generally describes excess overbite. An "open bite," by contrast, describes the opposite situation — where the front teeth don't overlap or touch at all when the back teeth are together. Getting familiar with the clinical terms your orthodontist uses can make it easier to understand exactly what's being described about your specific bite.
Can Overjet or Overbite Get Worse Over Time Without Treatment?
In some cases, yes, particularly if the underlying cause involves an ongoing habit like thumb sucking in a child or a skeletal growth pattern that hasn't finished developing. In adults, overjet and overbite are generally more stable over time on their own, though gradual age-related changes in the bite can still occur gradually over many years. This is one reason an orthodontic evaluation, even without an obvious problem, can be useful — catching a developing pattern early, especially in a growing child, often means simpler treatment than waiting until it's more pronounced.
How Overjet and Overbite Relate to Jaw Function
Beyond appearance, significant overjet or overbite can affect how comfortably the jaw closes and functions during chewing and speaking. A very deep overbite, for example, can sometimes contribute to excess wear on the lower front teeth or discomfort in the jaw joint over time. Correcting a significant discrepancy isn't just about how the smile looks — it often supports more comfortable, even function of the bite as well.
Frequently Asked Questions
Is some overjet and overbite always considered a problem?
No, a small, normal amount of both is expected in a healthy bite; treatment is generally recommended only when either measurement is significantly outside the normal range.
Can adults have their overjet or overbite corrected, or is it only treated in children?
Adults can have both corrected with braces or clear aligners; age doesn't prevent tooth movement, though significant skeletal cases may involve different treatment planning than in a growing child.
Does correcting overjet always require jaw surgery?
No, most overjet cases are dental rather than skeletal and are corrected with braces or aligners alone; surgery is reserved for significant skeletal discrepancies.
Can overjet or overbite come back after treatment if I don't wear a retainer?
Yes, both can shift back toward their original position without consistent retainer wear, which is why retention is an important part of the overall treatment plan.
What's the difference between an overbite and a "deep bite"?
They generally refer to the same thing — "deep bite" is the everyday term some patients use for a more significant-than-normal overbite, where the upper front teeth cover a larger portion of the lower front teeth than expected.
Disclaimer: The content on this blog is not intended to be a substitute for professional medical advice, diagnosis, or treatment. Always seek the advice of qualified health providers with questions you may have regarding medical conditions.