To straighten teeth, have a doctor with orthodontic qualifications examine you in person, and go back on schedule. Do not buy aligners online and wear them at home

Clear aligners are a Class II (2) medical device in China. The instructions require that you wear them under the guidance of a doctor with orthodontic qualifications, and that you go back regularly. The US drug regulator says it has not approved aligners sold straight to a person without a dentist's prescription. With nobody examining you in person, the bite can go crooked, teeth can move to the wrong place, there can be pain, and teeth can even fall out.

Cost

It costs more than buying online, for the registration and the return visits, and every so often you have to go to the clinic. The hard part is that the course often lasts 1 or 2 years, and you have to keep the return visits.

Benefit

The 2022 Guiding Principles for the Registration Review of Bracketless Aligners, from the Center for Medical Device Evaluation of the National Medical Products Administration, say that this kind of aligner has a "management category of Class II (2)." They require the instructions to state that "during treatment it must be worn under the guidance of a physician qualified in orthodontics," and also to state "the requirements for eating, brushing, and regular return visits." On the product name, they say it is "not recommended to contain empty, hypothetical conceptual names such as 'invisible'." The US Food and Drug Administration (FDA) says: "The FDA has not authorized clear aligners that are sold directly to consumers without a prescription and supervision by a dentist or orthodontist," meaning it has not approved a single clear aligner sold directly to a person without a dentist's prescription and supervision. The FDA also says: "In-person examination by a dentist or orthodontist can help lower the risks of uneven bite, unintended tooth movement, pain, and tooth loss," that is, an examination in person by a dentist or an orthodontist can lower the risk of an uneven bite, teeth moving where they should not, pain, and losing a tooth. After you start wearing them, only regular return visits in person can confirm that the teeth are moving safely as planned. Both of these are regulatory documents. Neither gives the proportion of people who come to harm.

Notes

The benefit magnitude is set at small, because no proportion of harm was found, so the judgment can only rest on the consequences. No risk alert from China's drug regulator or health departments, aimed at buying aligners online and wearing them at home, was found, so this item relies mainly on the registration requirements and on what the FDA says. Orthodontics is a medical act. For tooth straightening done as cosmetic medicine, the institution's license has to list the matching subject, and the doctor who does it has to be qualified. How to check is in item 2 of this section (the institution's license, and the attending physician). In 2023, 4 departments including the National Health Commission issued a notice on dental care. Where there is no practice license or clinic filing certificate, or non-health technicians are hired to treat teeth, the notice requires that they "be severely punished according to the law and the rules." Orthodontics is not reimbursed by yibao (医保 — basic medical insurance). See section 24, item 12 (ask the package price before you get a tooth implant).

Sources · 3

1. 国家药品监督管理局医疗器械技术审评中心 (2022). 无托槽矫治器注册审查指导原则（2022 年第 41 号）. cmde.org.cn/flfg/zdyz/zdyzwbk/202301030951161…
2. 国家卫生健康委办公厅等 (2023). 关于进一步推进口腔医疗服务和保障管理工作的通知（国卫办医政发〔2023〕11 号，第五部分第（二）项）. gov.cn/zhengce/zhengceku/202309/content_69037…
3. U.S. Food and Drug Administration (2026). Clear Dental Aligners（页面 2026 年 9 月 9 日更新）. fda.gov/medical-devices/dental-devices/clear-…