A bite problem — or malocclusion — is when the upper and lower teeth do not fit together the way they should. Some are mild and largely cosmetic. Others are significant enough to affect chewing, speech, jaw comfort, and the long-term health of the teeth and gums. At Dentist Pymble, we assess and treat bite problems for patients across the Ku-ring-gai region, and the right treatment depends on the type and severity of the problem and the age of the patient. This page covers the most common bite problems, why they matter, and the treatment options.

What is a bite problem?

A bite problem is any significant deviation from the ideal way the upper and lower teeth should meet when the jaw closes. The “ideal” is a Class I relationship, where the upper teeth sit slightly outside the lower teeth, the points of the molars interlock correctly, and the front teeth overlap vertically by about 1-2 millimetres. Anything outside that — overbite, underbite, crossbite, open bite, deep bite — is a malocclusion.

Most people have some degree of malocclusion. A small percentage have a malocclusion significant enough to need treatment, either for function, for the long-term health of the teeth and gums, or for cosmetic reasons. The decision to treat is a shared one between the patient and the dentist or orthodontist, based on the severity, the symptoms, and what the patient wants to change.

Overbite, underbite, crossbite — what’s the difference?

The three most commonly confused bite problems:

• Overbite (Class II) — the upper teeth sit too far forward of (or overlap too far over) the lower teeth. Often called “buck teeth” in its most visible form. Usually relates to the lower jaw being set back, the upper jaw being set forward, or a combination of both.
• Underbite (Class III) — the lower teeth sit in front of the upper teeth. The most visually distinctive malocclusion, and the one most likely to need surgical correction in severe cases. Usually relates to the lower jaw being set forward or the upper jaw being set back.
• Crossbite — the upper teeth sit *inside* the lower teeth when the jaw closes. Can affect a single tooth (often a result of crowding) or a whole segment of teeth (often a result of a narrow upper jaw).

There are other bite problems too — open bite (front teeth don’t meet when the back teeth are closed, often from a tongue thrust or prolonged thumb-sucking), deep bite (upper front teeth cover too much of the lower front teeth), and edge-to-edge bite (front teeth meet tip to tip, which accelerates wear). The treatment for each is different, which is why a proper orthodontic assessment matters.

Why bite problems matter

The cosmetic impact is the most visible reason to treat, but it is not the only one. Bite problems contribute to a range of functional issues:

• Accelerated tooth wear — teeth that meet in the wrong place wear down faster
• TMJ symptoms — jaw pain, clicking, headaches, muscle tension
• Gum recession — particularly with crossbites, where the wrong forces are placed on the gum
• Difficulty chewing or speaking — particularly with severe open bites or underbites
• Asymmetric jaw growth — in children, an untreated crossbite can lead to the jaw growing unevenly
• Increased risk of dental trauma — protruded upper front teeth are more likely to be chipped or knocked out

None of this is inevitable, and a small malocclusion that is stable and symptom-free may not need any treatment. The right answer depends on the case, not the rule.

Treatment options for bite correction

Treatment depends on the type and severity of the malocclusion, the age of the patient, and what they want to achieve. The main options:

• Invisalign — clear aligners that move the teeth in small, planned increments. Works well for mild to moderate bite problems, particularly in adults who want a discreet option.
• Fixed braces — metal or ceramic brackets and wires. Still the workhorse for more complex bite problems, particularly in teenagers and young adults.
• Functional appliances — removable devices used mostly in growing children to modify jaw growth (e.g., headgear, twin block, Herbst).
• Orthognathic surgery — jaw surgery combined with orthodontics for severe skeletal bite problems that cannot be resolved with orthodontics alone.
• Composite bonding or veneers — sometimes a viable alternative for mild bite problems where the patient does not want orthodontics, with the trade-off that some tooth structure is modified.

We will always lay out the options with their pros, cons, timeframes, and costs at the orthodontic assessment appointment, and we will be straight with you about whether treatment is needed, whether it can wait, or whether it is genuinely optional.

Can Invisalign fix bite problems?

For many bite problems, yes. Invisalign has evolved significantly over the last decade, and the range of malocclusions it can treat is much wider than it used to be. Mild to moderate Class I and Class II cases, many crossbites, open bites, and deep bites can all be treated with Invisalign in the hands of an experienced provider.

For more complex cases — severe Class II with a significantly retruded lower jaw, severe Class III with a protruded lower jaw, or cases requiring significant jaw expansion — fixed braces or a combination of braces and surgery may be the more predictable option. We will always be straight with you about which option is most likely to give you the result you want.

When is jaw surgery needed?

Jaw surgery (orthognathic surgery) is reserved for the most severe skeletal bite problems — where the upper or lower jaw is in the wrong position relative to the other, and where moving the teeth alone cannot fix the underlying skeletal discrepancy. It is a hospital-based procedure done under general anaesthetic, usually as a day-stay or overnight stay, with a recovery period of 2-4 weeks off work and 6-12 months of combined orthodontics and surgical planning and follow-up.

It is not a first-line treatment, and most bite problems do not need it. But for the right patient — usually someone with a significant Class III underbite, a severe Class II with a retruded lower jaw, or a facial asymmetry that cannot be corrected any other way — the combination of orthodontics and jaw surgery produces a result that orthodontics alone simply cannot match.

If you live in Pymble, Gordon, Turramurra, Wahroonga or anywhere else in the Ku-ring-gai area and you have a bite problem you have been thinking about, call our practice. We see neighbouring Gordon patients and other nearby residents, and the first conversation is always a free one — no commitment, just information.

Frequently asked questions

How do I know if I have a bite problem? Common signs include teeth that meet unevenly, difficulty biting into foods like apples or corn on the cob, jaw pain or clicking, accelerated wear on certain teeth, and a visible difference between how the upper and lower teeth align. The only way to confirm is with an orthodontic assessment.

At what age should bite problems be treated? For children, an orthodontic assessment is recommended around age 7-10, when early intervention can sometimes prevent a more complex problem from developing. For adults, there is no upper age limit — orthodontic treatment works at any age, provided the teeth and gums are healthy enough to support it.

Is Invisalign or braces better for bite problems? It depends on the case. Invisalign is more discreet and often more comfortable, and works well for many mild to moderate cases. Fixed braces are still the more predictable option for complex cases, particularly those involving significant tooth movement or jaw realignment.

Will I need teeth removed for bite correction? Sometimes, but not always. Extractions are more common in cases of significant crowding or where the teeth need to be moved a long distance to close a gap. Modern orthodontics tries to avoid extractions where possible, and your orthodontist will discuss this at the assessment.

How long does bite correction take? Most orthodontic treatment takes 12-24 months. Simple cases can be done in 6-12 months, complex cases 24-36 months. The exact timeframe depends on the severity of the problem, the type of treatment, and how well you follow the instructions (particularly with removable aligners).