The period around age six marks a major transformation in a child’s oral development, shifting from a full set of primary teeth toward a lifelong adult dentition. Parents often notice this change when a first tooth becomes loose or a new, larger molar appears unexpectedly at the back of the mouth. This transition involves the simultaneous shedding of baby teeth and the eruption of permanent teeth, leading to a temporary state of uneven dental arches. Understanding this dynamic phase is important for maintaining good oral health, as the teeth erupting now are meant to last a lifetime.
The Typical Tooth Count at Age Six
A child at age six typically has a tooth count that is in flux, ranging from 20 to 24 teeth. Most children still retain the full set of 20 primary teeth, which aid in chewing, speech development, and holding space for the permanent teeth developing beneath the gums. The increase in count comes from the appearance of the first permanent molars, often called the “six-year molars.” These molars erupt into the arch behind the existing primary teeth. Since there are four of these molars—one in each corner of the mouth—the total number of teeth can increase to 24 when all four have fully emerged.
The Process of Mixed Dentition
The co-existence of both primary and permanent teeth is formally known as the mixed dentition stage, which begins around age six and generally lasts until 12 or 13. This transition is not a simple one-for-one replacement, as two different processes occur simultaneously. The lower central incisors are usually the first baby teeth to loosen and fall out, replaced by their permanent successors, which include the incisors, canines, and premolars.
The eruption of the first permanent molars is a new addition to the dental arch, rather than a replacement. These four molars emerge into the jaw space located behind the primary teeth. Because they do not replace a baby tooth, their arrival can sometimes go unnoticed by parents, despite their importance in establishing the foundation for the adult bite. This period creates a visible contrast in the mouth, as the new permanent teeth are often slightly larger and less white compared to the smaller primary teeth.
Essential Dental Care for Transitional Teeth
Managing the mixed dentition phase requires specific attention to newly erupted and loosened teeth. When a primary tooth becomes loose, the root is resorbed by the underlying permanent tooth, a natural process known as exfoliation. Children should be encouraged to gently wiggle the tooth until it falls out naturally. If a permanent tooth begins to emerge behind a baby tooth that is not yet loose (sometimes called “shark teeth”), a dental visit is warranted to determine if the primary tooth needs professional removal.
The newly erupted permanent molars are susceptible to decay because they have deep grooves on the chewing surfaces that are difficult to clean effectively. These molars should be brushed thoroughly with fluoride toothpaste. Pediatric dentists often recommend the application of dental sealants, which are thin plastic coatings that fill in these grooves, providing a protective barrier against plaque and bacteria. This is also a suitable time for a first orthodontic evaluation to monitor the growth of the jaw and the proper alignment of the erupting permanent teeth.