Dental development around age six represents a major change in a child’s mouth. This period, known as mixed dentition, involves the coexistence of primary (baby) teeth and newly arriving permanent teeth. Understanding this transition is important because it sets the stage for a healthy adult smile. Proper care of these emerging teeth is a priority for parents.
The Exact Count: Primary and Permanent Teeth
A full set of primary teeth consists of 20 teeth, while a full adult set includes 32 teeth. At age six, a child’s tooth count is dynamic, typically ranging from 20 to 24 teeth. This range occurs because the child still possesses all 20 primary teeth, and the first permanent molars are often erupting before any primary teeth have been lost.
The additional teeth are the four permanent first molars, which emerge at the very back of the mouth, two on the top and two on the bottom. These new permanent teeth are noticeably larger and may appear slightly more yellow than the primary teeth they are joining.
Understanding the Mixed Dentition Stage
The presence of both primary and permanent teeth defines the mixed dentition stage, which generally begins around age six and lasts until age 12 or 13. This stage is characterized by the natural shedding of the 20 primary teeth as the permanent teeth develop beneath them. The roots of the primary teeth slowly weaken and dissolve as the permanent teeth push up, causing the baby tooth to become loose and eventually fall out.
The first primary teeth to be shed are typically the lower central incisors, the two front teeth on the bottom arch. This process of loss and replacement follows a general sequence over several years. Primary teeth are important because they help with chewing and speech, and they function as placeholders, guiding the permanent teeth into their correct positions.
Crucial Dental Milestones at Age Six
The emergence of the first permanent molars, often called the “6-year molars,” is a significant event that usually happens around the sixth birthday. These four teeth erupt directly behind the last primary molars and do not replace any baby teeth, making them new additions to the mouth. Because they do not replace a loose tooth, parents often miss their arrival.
These molars establish the foundation of the bite and help shape the child’s lower face. Given their grooved chewing surfaces and their location at the back of the mouth, they are highly susceptible to trapping food debris and are a frequent site for cavities. Dentists often recommend applying dental sealants to these permanent molars soon after they erupt, as this protective layer can prevent up to 80% of cavities in the back teeth.
Maintaining Oral Health During Transition
Brushing and flossing during the mixed dentition stage requires special attention to ensure all surfaces are cleaned effectively. Parents should supervise brushing until a child can reliably spit out toothpaste, which is typically around age six. Use a pea-sized amount of fluoride toothpaste, focusing the toothbrush on the chewing surfaces and the gumline of the newly erupted permanent molars.
Daily flossing is important, especially where two teeth touch, because a toothbrush cannot reach these contact points. When a primary tooth becomes loose, gentle wiggling is fine, but forcing it out should be avoided to prevent gum trauma. Parents should consult a dentist if a permanent tooth begins to erupt before the corresponding baby tooth has fallen out, or if there are concerns about crowding or delayed eruption. Regular dental check-ups twice a year monitor the eruption process and allow for preventative treatments like fluoride varnish and sealants.