Primary teeth, also known as deciduous teeth, play a foundational role in the development of the jaw structure and facilitate clear speech patterns. These temporary teeth maintain the proper spacing necessary for the permanent teeth forming underneath the gums. Their presence guides the alignment of the jaw and influences the eruption path of their successors.
The Total Number of Baby Teeth Lost
A child’s mouth contains a total of 20 deciduous teeth, all of which will eventually be lost during the transition to permanent adult dentition. This set is divided equally, with 10 teeth in the upper jaw and 10 in the lower jaw. The composition includes four central incisors, four lateral incisors, four canines, and eight molars. These 20 teeth function as placeholders for the permanent set.
The process of losing these teeth is triggered by the permanent tooth buds developing beneath them. As the adult teeth grow, they exert pressure that causes the roots of the baby teeth to gradually dissolve, a process called resorption. This root dissolution causes the tooth to become loose and eventually fall out, allowing the permanent tooth to take its position.
The Typical Timeline and Sequence for Tooth Loss
The natural shedding of primary teeth typically begins around the age of six, a period often coinciding with the eruption of the first permanent molars at the back of the mouth. The full transition from a primary to a permanent set of teeth is a years-long process that usually concludes by ages 12 or 13. The timing can vary widely between individuals, but the general sequence of loss tends to follow the order in which the teeth first appeared.
The lower central incisors, the two front teeth on the bottom arch, are almost always the very first to become loose and fall out. These are closely followed by the upper central incisors, the corresponding teeth in the upper jaw. Next in the sequence are the lateral incisors, which are the teeth immediately flanking the central incisors on both the top and bottom arches. This initial phase of losing the eight front teeth generally occurs between the ages of six and eight.
The remaining teeth, including the first molars, the canines, and the second molars, are typically lost between the ages of nine and twelve. The first molars are usually shed before the canines, even though the canines erupted earlier in infancy. Finally, the primary second molars, located furthest back in the jaw, are the last baby teeth to be lost, completing the process of deciduous tooth shedding. While this sequence provides a reliable guide, a variation of six months to a year on either side of these averages is well within the range of normal development.
Addressing Common Concerns During the Transition
One frequent concern for parents is the appearance of “shark teeth,” which occurs when the permanent tooth erupts behind the baby tooth before the primary tooth has fallen out. This is most common with the lower front teeth, where the permanent tooth often emerges on the tongue side of the arch. In many cases, once the loose baby tooth is removed, the tongue’s natural pressure will guide the newly emerged permanent tooth forward into the correct alignment.
Mild discomfort and soreness around a loose tooth are normal, but significant pain or swelling is not and should be evaluated by a dentist immediately. The natural wiggling of a loose tooth by the child is generally encouraged, as it helps the final root fragments dissolve and accelerates the shedding process. If a baby tooth remains firmly in place long after its expected time, or if the permanent tooth is visibly coming in crooked, a dental evaluation may be necessary to determine if extraction is needed.
As permanent teeth erupt, their surface is more porous and susceptible to decay than baby teeth, requiring a heightened focus on oral hygiene. Children should brush twice daily with fluoride toothpaste and floss once a day, especially as soon as two teeth are touching. The molars that arrive around age six are permanent and do not replace baby teeth, making dental sealants a recommended preventive measure to protect their deeply grooved surfaces.