Broadcaster Jeong Seon-hee reveals year of braces — what can orthodontic treatment really change?

Broadcaster Jeong Seon-hee's disclosure that she underwent orthodontic treatment has drawn fresh attention to what braces can — and cannot — do. Orthodontic treatment is often dismissed as a purely cosmetic procedure for straightening teeth, but it also addresses bite alignment and overall oral health.

Jeong appeared Tuesday on "Sinnyeoseong," a segment of the YouTube channel Rolling Thunder, alongside Lee Gyeong-sil and Jo Hye-ryeon. During a conversation about appearances, she pointed to her teeth and said, "I had braces to bring my mouth in a bit. I did it for a year."

She added that the orthodontist was a high school classmate of broadcaster Shin Dong-yeop. "He said he had found a set of teeth he really wanted to work on," she said. Lee and Jo responded with remarks like "Now that you mention it, they have moved in a little" and "They look so pretty." Jeong also admitted, "From the side, I used to have a bit of an overhang."

Orthodontic treatment gradually repositions crooked, gapped, or protruding teeth and corrects malocclusion using various appliances — fixed brackets and wires, clear aligners, and lingual braces among them. The core principle is to apply continuous pressure to move teeth into better positions after evaluating the relationship between the teeth and jaw. The Cleveland Clinic notes that orthodontic treatment can help reduce the risk of cavities, gum disease, and tooth wear by improving tooth alignment and the way upper and lower teeth meet.

The reason braces can change a person's appearance is that the teeth, lips, and jawline all contribute to the balance of the lower face. When the front teeth are significantly tilted forward or the lips are pushed out by the teeth, correcting that protrusion can visibly alter the look of the mouth area. Conversely, when teeth are severely set back or the bite is misaligned, straightening them can make the smile and lip line look more refined.

However, not every case of protruding lips can be resolved with braces alone. If the issue stems from the position or angle of the teeth, orthodontic treatment may help — but when the underlying cause is a skeletal problem involving the position of the upper or lower jawbone itself, braces have their limits. In such cases, a specialist in orthodontics should be consulted after a thorough examination to determine whether tooth extraction, non-extraction treatment, or corrective jaw surgery is appropriate.

The benefits of orthodontic treatment extend well beyond aesthetics. Overlapping or crooked teeth make brushing harder, allowing plaque to accumulate and raising the risk of cavities and gum disease. When the upper and lower teeth do not meet properly, excessive force can concentrate on certain teeth, leading to wear, jaw joint discomfort, and reduced chewing function. The UK's National Health Service similarly describes orthodontic treatment as a way to correct crooked, protruding, or gapped teeth and improve how the upper and lower teeth bite together.

Treatment length varies by individual. It generally depends on the severity of the misalignment, the patient's age, whether teeth are extracted, the type of appliance used, and patient compliance. The NHS says fixed braces are typically worn for one to two years, while the Cleveland Clinic puts the average at about two years, with some cases requiring up to three.

Adults are not excluded from orthodontic treatment. Anyone with healthy teeth and gums can undergo braces at any age. That said, tooth movement tends to be slower in adults than in adolescents who are still growing, and factors such as gum disease, dental prosthetics, implants, and missing teeth must also be considered. The American Association of Orthodontists notes that healthy teeth can be moved at any age, and that adults may consider orthodontic treatment not only for cosmetic reasons but also for functional improvement and long-term oral health.

A thorough diagnosis is required before treatment begins. Dentists assess tooth alignment, jawbone structure, and gum condition using oral examinations, X-rays, intraoral scans or dental impressions, and facial and oral photographs. Any cavities or gum disease must be treated before braces are fitted. Oral hygiene is particularly important at the outset, since brushing becomes more difficult once appliances are in place.

Pain and discomfort are common during treatment. Teeth may feel sore and chewing may be difficult immediately after appliances are first fitted or after wire adjustments. The inside of the mouth can become irritated where it rubs against brackets, and clear aligners may initially affect speech. Most patients adapt over time, but severe pain or a sharp appliance should be addressed by a clinician.

Oral hygiene is essential throughout treatment. Food particles and plaque accumulate easily around orthodontic appliances, and inadequate brushing can cause white-spot lesions on tooth surfaces, cavities, or gum inflammation. The NHS states that patients must be able to maintain good oral hygiene before starting orthodontic treatment, and that the risk of cavities and gum problems increases during treatment.

Dietary choices also require care. Hard, tough, or sticky foods can damage brackets or wires, and frequent breakages can extend the overall treatment time. During fixed-appliance treatment, patients should avoid foods that strain the hardware — such as hard candy, caramel, dried squid, and hard nuts — and cut food into small pieces before eating.

The most commonly cited risks of orthodontic treatment include tooth demineralization, cavities, gum inflammation, pain, mouth sores, root resorption, and post-treatment relapse. Research involving orthodontic specialists has similarly identified demineralization, relapse, root resorption, pain, gum inflammation, oral ulcers, appliance breakage, and treatment duration as key risks that should be explained to patients.

Care does not end when treatment does. Teeth that have been moved by braces tend to drift back toward their original positions, making retainer wear essential. Failing to wear a retainer as directed can cause the teeth to shift again. It is therefore important to use a fixed or removable retainer consistently for as long and in the manner prescribed by the treating clinician.

Orthodontic treatment is not a quick cosmetic fix — it is a process lasting months to years that adjusts the balance of the teeth, gums, and jaw. While improvements in appearance are possible, patients should first confirm whether their concern stems from tooth alignment or from the underlying bone structure. Rather than pursuing unrealistically fast results, the safer approach is to develop a long-term plan that accounts for thorough diagnosis, ongoing oral hygiene, and consistent retainer use after treatment ends.