I’m a believer in two-phase treatment. I recommend two-phase treatment when young patients (usually 7 to 10 years old) have problems so severe that waiting until they are teenagers would make treatment more difficult, take longer, or leave them socially handicapped through their elementary and junior high years. But what about starting treatment in teenagers who still have baby teeth remaining? Do all baby teeth need to be gone before the second or comprehensive phase of treatment begins?

Baby teeth are usually gone by age 13
One of the first things I look for in an initial orthodontic exam in teenagers is the presence of primary or baby teeth. If a patient is 13 years old and still has baby teeth remaining, it could signal that their overall dental development is delayed. One indicator is the status of their 12-year-molars. If they are not yet erupted, there’s a good chance that development is just behind schedule. Another sign is that the teeth are being lost in the appropriate sequence, just delayed. For example, if all four primary second molars remain in a 13-year-old, the patient is probably just slow. Conversely, if only one primary second molar remains and it is not loose but the other three are gone and their replacements are in, it is probable that there is something amiss with that final molar. Symmetry and patterns of tooth loss are a critical part of diagnosis.

Sometimes the remaining baby teeth need to be removed
If a patient’s overall development is delayed, the decision to remove the remaining baby teeth is determined by several factors. The first is the patient’s age. If they are 14 or 15, I will usually recommend having the remaining baby teeth removed so that they can get their treatment finished before they graduate from high school. Second, if the formation of the roots of the unerupted teeth is nearing completion but the associated baby teeth are not loose, extractions are also indicated. Finally, if the 12-year molars are fully erupted but baby teeth remain, I will usually recommend having the remaining primary teeth removed so that treatment can begin.

There are times when treatment needs to begin early
Although I prefer to wait until all of the primary teeth are gone, there are times when it is appropriate to begin treatment early. One is the presence of an impacted or blocked out tooth (crowding). If a baby tooth has not been lost because the underlying tooth does not have enough room to come in, we will usually begin treatment with the associated baby tooth in place. Sometimes making room for the underlying tooth will help the baby tooth become loose on its own. If not, we may have the baby tooth removed by the family dentist. Another time I’ll start treatment before all of the baby teeth are gone is if the patient’s smile is socially handicapping. Finally, if we’re planning on keeping a baby tooth because the underlying permanent tooth is missing, the presence of the baby tooth will have no bearing on the starting time.

Starting treatment after all of the primary teeth are gone generally keeps the treatment length as short as possible, minimizes the amount of school and work that patients and their families miss, and reduces the probability of adverse consequences that can accompany extended orthodontic treatment (white spot lesions, puffy gums, root resorption, etc.) If there is a good reason to get started while there are still primary teeth however, that’s what we’ll do.

NOTE: The author, Dr. Greg Jorgensen, is a board-certified orthodontist who is in the private practice of orthodontics in Rio Rancho, New Mexico (a suburb on the Westside of Albuquerque). He was trained at BYU, Washington University in St. Louis, and the University of Iowa in the United States. Dr. Jorgensen’s 25 years of specialty practice and nearly 10,000 finished cases qualify him an expert in two-phase treatment, extraction and non-extraction therapy, functional orthodontics, clear aligners (Invisalign), and multiple bracket systems (including conventional braces, Damon and other self-ligating brackets, Suresmile, and lingual braces). This blog is for informational purposes only and is designed to help consumers understand currently accepted orthodontic concepts. It is not a venue for debating alternative treatment theories. Dr. Jorgensen is licensed to diagnose and treat patients only in the state of New Mexico. He cannot diagnose cases described in comments nor can he select treatment plans for readers. Because he has about 40,000 readers each month, it is impossible for him respond to all questions. Please read all of the comments associated with each article as most of the questions he receives each week have been asked and answered previously. The opinions expressed here are protected by copyright laws and can only be used with written permission from the author.