CASE · Orthodontics
Open Bite and Facial Asymmetry Treated Without Surgery Using MARPE (Case Study)
“My front teeth don’t meet.” “My face is asymmetric.” “I want my lips to sit further back.” This woman in her early 20s had been told she needed surgery. On close examination, all three problems came from one cause: an upper jaw that was too small for the lower jaw. We widened the upper jaw itself with MARPE and treated her without surgery.
Case at a glance
- Concern: Front teeth that don’t meet, facial asymmetry, a protruding mouth (woman in her early 20s)
- Diagnosis: anterior open bite even when the molars bite; facial asymmetry (the right jaw is longer); mild protrusion; one upper left tooth missing with spaces throughout
- Root cause: a narrow upper jaw, with the lower molars tipped inward to meet the upper teeth
- Treatment: (1) MARPE to widen the upper jaw, (2) correct the molar bite, (3) align the teeth and use a right-side mini-screw to intrude the upper teeth slightly, reducing the look of asymmetry
How can a small upper jaw cause three problems?
- Open bite: a narrow upper jaw leaves too little room for the tongue, which rests forward and keeps pushing the front teeth apart
- Protrusion: with too little space, the teeth are pushed forward; because she was missing one upper left tooth, the teeth spread into that space instead of crowding
- Asymmetry: the teeth cannot meet evenly, so one side contacts first and the bite height becomes uneven; her right jaw was already longer, and the uneven bite made it more noticeable
Normally the upper jaw is slightly wider, so the upper teeth wrap around the lower teeth. Her upper jaw was so narrow that the lower molars sat further out and had tipped inward to reach the upper teeth.
Can an adult’s upper jaw really be widened?
Braces move teeth; they generally cannot change the size of bone that has stopped growing. The exception is that the upper jaw can be widened.
In adults the midpalatal suture is fused, so traditional expanders often just tipped the teeth outward, which is why expansion was thought to work only in children. MARPE uses mini-screws in the palate and applies force to both the screws and the teeth to widen the bone itself. With the screws as a rigid anchor, the suture can be opened in adults without surgery.
How did treatment proceed?
- Step 1: widen the narrow upper jaw with MARPE so the jaw widths start to match
- Step 2: correct the molar bite; the tongue returns to its proper place and the front open bite improves a lot
- Step 3: align the front teeth into the new space, and use a right-side mini-screw to intrude the upper teeth slightly so the right side bites a little deeper, making the longer right jaw look shorter
What did the result look like?
Once the upper jaw was wider and the tongue moved back into place, the force pushing on the front teeth disappeared and they now meet. She can bite food with her front teeth and her smile looks natural. With room to align, the protruding teeth moved back and her lip line followed. By leveling the bite on both sides and intruding the right upper teeth slightly, the visible asymmetry improved within skeletal limits.
When is surgery still needed?
Not every case that is told it needs surgery can be treated with braces alone. With large skeletal problems, surgery may be necessary, and the length of the jaw bone itself can only be changed surgically. When the cause is identified precisely and the right appliance is used, a satisfying result without surgery is sometimes possible. Discuss your options with an orthodontic specialist. Fees depend on the appliance and time and are quoted after an examination.
Frequently asked questions
Does MARPE hurt?
The mini-screws are placed under local anesthesia. During expansion you feel pressure or discomfort, and local inflammation can occur.
Can every adult be expanded with MARPE?
Response varies with age and bone. We check with CT and other records before deciding.
Can facial asymmetry be fixed?
Asymmetry from an uneven bite can improve, but differences in bone length can only be changed with surgery.
Does an open bite relapse easily?
Tongue habits can cause relapse, so retainers and attention to tongue position are important.
About the reviewer
Dr. Sunmin Kim is the lead dentist at Ceramic Dental Clinic in Gangnam, Seoul, a board-certified orthodontist (Ministry of Health and Welfare, Korea) with a PhD from Tokyo Medical and Dental University. Our clinic is registered with the Ministry of Health and Welfare to treat international patients.
Important information
This is a real case. Results, treatment time and the number of visits vary from person to person.
During orthodontic treatment, temporary pain or discomfort, gum recession and root resorption can occur. Teeth can shift back if retainers are not worn after treatment. Mini-screws (TADs) can cause local inflammation or come loose.
Photos show teeth and X-rays only and are published with the patient’s consent.
Questions about your own teeth?
Send us photos of your teeth for a preliminary opinion. A final plan and quote are given after an in-person examination.
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