- An Open Bite
What: The upper teeth do not overlap the lower teeth, thus the teeth do not meet when the mouth is closed. It can occur at the front teeth (anterior open bite) or at the sides.
How It Happens: Prolonged thumb or pacifier-sucking can cause anterior open bites. More severe open bites are due to an underlying skeletal reason, such as the vertical growth of the jaws. Children can go through a phase with an anterior open bite. This occurs when the baby incisors have dropped and the permanent incisors have yet to erupt.
Best Time To Treat: When the permanent incisors erupt at six or seven years old. Sucking may cause problems with the proper growth of the jaws and alignment of the teeth.
Treatment: Begin by helping the child break the habit of thumb or pacifier-sucking.
Children often suck their thumbs when they feel insecure or need comfort. Focus on correcting the cause of the anxiety.
Let the older children decide on the method of stopping the habit, such as bandaging the thumb or putting a sock over the hand at night when thumb-sucking usually occurs.
Bitter medication to coat the thumb is available.
If the thumb-sucking persists, seek help from an orthodontist, who can custom-make a habit appliance where parts of it extend behind the upper front teeth to prevent the thumb from pressing or resting on the teeth.
Habit appliances can effectively close the majority of anterior open bites which arise from thumb- sucking. If the open bite persists, braces will be needed at a later age to close the bite and align the teeth.
Approximate Cost: Habit appliances cost from $650 at the National Dental Centre of Singapore. In the private sector, they cost between $1,000 and $1,500.
What: The upper front teeth reach too far down over the lower front teeth.
This can cause the lower teeth to bite into the roof of the mouth. In severe cases, it can damage the gums around the upper incisors.
The upper incisors are commonly protruded and flared, resulting in a “buck teeth” appearance and an increased risk of trauma to the upper incisors. This is known as a Class II malocclusion.
How It Happens: There is an imbalance in the jaws or a malalignment of the teeth, resulting in the upper teeth overlapping the lower teeth, sometimes even covering the lower teeth completely.
Best Time To Treat: When the bad bite starts to damage the gums on the palate behind the upper front teeth. The ideal time for treatment of a Class II malocclusion is during the pubertal growth spurt.
Treatment: If there is traumatic overbite, a simple upper removable bite plate can be used to protect the upper gums.
In Class II malocclusion cases, treatment is usually started early if the child with protruding front teeth is extremely accident- prone.
A functional appliance (a type of brace) is worn to position the lower jaw in a more forward position.
A second phase of treatment with braces is necessary at a later age, though it may be less complicated.
Cost: At the NDCS, simple appliances such as an upper removable bite plate cost from $650 and functional ones cost from $865.
In the private sector, the cost is between $850 and $1,200 for a simple appliance and between $1,200 and $2,000 for functional ones.
What: When a person bites down, the upper front teeth fall behind the lower front teeth.
How It Happens: A lack of space for the permanent incisors or, sometimes, this could be due to the skeletal imbalance of the jaws where the lower jaw is more forward in position compared to the upper jaw.
Best Time To Treat: Between six and eight years old when the permanent incisors have erupted.
If not treated, this may cause wearing down of the teeth and gingival (gum) recession, resulting in the lower teeth being mobile or shaky. This can also affect the normal growth of the lower jaw.
Treatment: For simple cases, an upper removable plate with springs can push out the upper teeth.
For very mild cases, biting on an ice cream stick to encourage tipping of the upper teeth forward and the lower tooth teeth inward will help.
If there is insufficient space in the mouth, fixed braces on the front four incisors may be required.
In more severe cases where the crossbite is due to an underdeveloped upper jaw, a face mask may be required.
This special appliance pulls the upper jaw and teeth forward to encourage growth of the upper jaw. This is also known as a reverse pull headgear.
Cost: At NDCS, simple upper removable appliances cost from $650 and from $865 for more complex treatments.
In the private sector, it is between $850 and $1,200 for simple upper removable appliances and between $1,200 and $2,000 for complex treatments.
What: When a person bites down, the upper teeth at the side of the mouth fall inside the lower teeth, instead of over them. This can happen on one or both sides of the jaw. Posterior crossbites may promote asymmetrical growth of the jaws.
How It Happens: This occurs when the upper jaw is narrower than the lower jaw. It is caused by habits such as finger or pacifier-sucking, or if the child has an upper airway obstruction due to enlarged adenoid tissues or a nasal allergy.
The pressure of the sucking action, which varies according to the frequency and intensity of the sucking, causes the upper jaw to narrow.
Upper airway obstructions result in a person breathing through the mouth instead of the nose. This can affect the development of the face, jaws and teeth.
Best Time To Treat: Around eight to 10 years old. Early treatment allows for expansion of the upper jaw, which is easier in young children than in adults.
Expanding the upper jaw in younger children – such as preschoolers- with heavy forces and at too frequent a rate may lead to undesirable changes in the nose.
Consult an orthodontist on the ideal time for treatment and the best type of appliance.
Treatment: A palate expander is used to widen the upper jaw for several months.
This can be a removable appliance, such as an expansion plate, which is removed only when eating, brushing the teeth and playing sports. It can be a fixed appliance like a quad-helix, which is for the upper teeth and is cemented in the mouth.
Cost: At NDCS, removable appliances cost from $650 and fixed appliances cost from $890.
In the private sector, removable appliances cost between $850 and $1,200. Fixed appliances cost between $1,000 and $1,500.
Text: Joan Chew/The Straits Times
Additional Reporting: Atika Lim
Photos: Association of Orthodontists