Common Orthodontic Questions Answered

These are among the most commonly asked questions to orthodontists by their patients and the parents of their patients.

Do Friction-less Brackets (Self-ligating brackets) reduce treatment time compare to conventional brackets?

In recent years, self-ligating brackets have become popular among orthodontists due to the claim by the manufactures of these appliances that self-ligating brackets create less friction with faster tooth movement, which would result in shorter treatment time.

However recent published studies evaluating effectiveness of self-ligating brackets show that self-ligating brackets and conventional brackets treat malocclusion in relatively same amount of time and with a similar number of appointments. So shorter treatment time is not a proven reason to use these brackets.

Does tooth extraction in an orthodontic treatment cause joint disorder or compromise facial esthetics?

Esthetics is usually judged by the quality of smile and the person's profile. There are no studies documenting the fact that smiles are less esthetic after an orthodontic treatment with tooth extraction. Almost all studies show that the difference between post treatment profiles of extraction and non-extraction patients is not detectable. For example judges could not distinguish between the photos of extraction and non-extraction treatments in most cases. Extraction of teeth does not cause joint disorder.

Does early trauma to primary tooth cause discoloration of the permanent tooth?

Injuries to the primary teeth are very likely when kids are three years old or younger learning how to walk and are less stable. Recent studies have shown that injury to the primary tooth can cause a yellow-brown or a white spot discoloration to the enamel of the permanent tooth.

How does orthodontic treatment affect Jaw Joint Disorder- Tempromandibular Disorder (TMD)?

Orthodontic treatment neither causes nor prevents TMD. The result of a very large epidemiologic study that looked into relationship of orthodontic treatment to TMD showed:

• No significant association between a bad bite and persistent TMD


• No significant association between orthodontic treatment and TMD incidence


• TMD prevalence is higher in females than males


• Being a female was found to be a predictor for both incidence and persistence of TMD


• TMD prevalence was highest at age 19-20

Should I extract my third molars (wisdom teeth)?

There is no good data to support the fact that eruption of third molars can cause relapse of crowding after an orthodontic treatment. It is recommended, however, to remove third molars if it improves the health of second molars (tipped third molars can cause cavity for second molars) or if they are not fully erupted. If the third molars are completely under the bone and left intact, the possibility of fracture of the lower jaw is 2.5 times higher during a traumatic accident.

Is using a pacifier under the age of five related to the bite problems (e.g. posterior cross bite)?

The odds of developing a posterior cross bite are 50% greater when a pacifier is used and cross bite is not self-correcting once the habit is stopped. However, there are other factors causing cross bite such as genetic disposition and respiratory function.

How to treat the under bite or edge-to-edge bite with headgear

The best age to check with an orthodontist for an under bite is age 7 to 8. To correct skeletal under bite (upper jaw smaller than lower jaw), we need to take advantage of the upper jaw growth. However, on the average, upper jaw growth diminishes significantly by age 11, so the best time to treat these cases is from age 7-10. Treatment will require wearing a headgear to pull the upper jaw forward (bone movement) at least 14 hours a day, including nighttime sleeping with it. The upper jaw is moved forward continuously until the growth of the lower jaw stops. More than 75% of time this modality of treatment has long-term success, however, surgical treatment may be necessary if the patient is not seen at the right time (before age 11), or if the patient is not cooperating in wearing the headgear during the orthodontic treatment, and/or the amount of growth of the lower jaw is significant.