The process of a child losing baby teeth and gaining permanent teeth is a normal, multi-year developmental milestone. Permanent teeth, also called adult teeth, begin to emerge around age six, initiating the mixed dentition stage. This period involves replacing 20 primary teeth with up to 32 permanent teeth, a journey that continues through the early teenage years. Understanding this timeline helps parents monitor their child’s oral health during the transition.
The Start of the Eruption Timeline
The first permanent teeth often erupt without any baby teeth having been shed, typically around the child’s sixth birthday. These initial arrivals are the first permanent molars, often called the “six-year molars,” which push through the gums at the very back of the jaw. These molars do not replace any primary teeth and provide a stable anchor for the developing bite. Their early presence helps correctly position the rest of the permanent teeth as they emerge.
Shortly after the first molars appear, or sometimes simultaneously, the lower central incisors begin to erupt, replacing the corresponding baby teeth. These lower front teeth are often the first primary teeth a child loses. The eruption of both the first molars and the lower incisors marks the official start of the mixed dentition phase, where both primary and permanent teeth coexist. This early phase, generally between ages six and seven, establishes the pattern for the sequential replacement of the remaining baby teeth.
Detailed Sequence of Permanent Teeth
Following the first molars and lower central incisors, the process continues predictably, with the remaining incisors emerging next, usually between ages seven and eight. The upper central incisors and the upper and lower lateral incisors, which sit on either side of the central incisors, complete the replacement of the front teeth. During this time, the jaw and facial bones are also growing, providing the necessary space for the larger permanent teeth.
The next group of teeth to emerge are the premolars and the canine teeth, with this phase spanning from ages nine through thirteen. The premolars replace the primary molars and usually erupt before the canines in the lower jaw. The first premolars appear between ages nine and eleven, followed by the second premolars between ages ten and twelve.
The permanent canine teeth, the pointed teeth next to the lateral incisors, have a different timeline in the upper and lower arches. Lower canines emerge around age nine or ten, while the upper canines appear later, between ages eleven and twelve.
The second permanent molars are the last of the regular teeth to erupt, coming in between ages eleven and thirteen, positioned just behind the first molars. By age thirteen, most children have 28 of their 32 permanent teeth. The final set, the third molars or wisdom teeth, are highly variable and may not appear until the late teens or early twenties, if at all.
Essential Care During the Transition
The years of mixed dentition require consistent monitoring by a dental professional to ensure a healthy transition. Regular checkups allow the dentist to track the eruption sequence and look for common developmental issues. X-rays are often used to confirm that the permanent teeth are developing correctly beneath the gums and are on track to emerge in the proper position.
A common concern is the appearance of gaps or spacing, known as diastema, between the newly erupted permanent front teeth. These spaces often close naturally as the remaining teeth, particularly the larger canines, emerge and push the incisors together. If a baby tooth does not fall out in time (retained primary teeth), the dentist may need to remove it to allow the permanent successor to erupt correctly.
Protecting the new permanent teeth from decay is a primary focus during this time. The first and second permanent molars, with their deeply grooved chewing surfaces, are particularly susceptible to cavities soon after they emerge. Dental sealants, which are thin protective coatings, can be applied to the molars’ surfaces to block food particles and bacteria from settling in the grooves.
Consistent use of fluoride toothpaste, using a pea-sized amount for children over age six, helps to strengthen the enamel of the newly erupted teeth. Parents should continue to supervise brushing until a child demonstrates the dexterity to brush effectively, usually around age seven or eight.