A common misconception is that babies are born with a full set of permanent teeth. Dental development is a detailed process that begins long before a child’s first tooth becomes visible. Understanding this journey helps parents support their child’s oral health from the earliest stages.
Teeth at Birth: Unpacking the Reality
Babies are not born with visible permanent teeth. At birth, a baby’s jaw already contains all 20 primary (baby) teeth, mostly formed but hidden beneath the gums. The tooth buds for the 32 permanent teeth are also developing within the jawbone, nestled below the primary teeth. Tooth bud formation starts early, around the sixth week of pregnancy for primary teeth, with permanent tooth buds beginning development around birth. The jawbones develop around these nascent teeth, preparing for their eventual eruption.
The Role of Primary Teeth
Primary teeth, also known as baby teeth, play important roles in a child’s development, even though they are temporary. There are 20 primary teeth: 10 in the upper jaw and 10 in the lower jaw. These teeth aid in chewing food, important for digestion and nutrition. They also contribute to speech development by helping children form sounds clearly.
Primary teeth hold space in the jaw for the permanent teeth. If primary teeth are lost too early due to decay or injury, surrounding teeth can shift, potentially causing alignment problems for emerging permanent teeth. The eruption of primary teeth begins around 6 months of age, with the lower central incisors appearing first. Children have their complete set of 20 primary teeth by age three.
The Arrival of Permanent Teeth
The transition from primary to permanent teeth is a gradual process known as exfoliation, beginning around age six. As permanent teeth develop beneath the gums, they exert pressure on the roots of primary teeth, causing these roots to dissolve. This root resorption weakens primary teeth, making them loose and allowing them to fall out. The first permanent teeth to emerge are the first molars, which appear behind the last primary teeth, and the lower central incisors.
Children enter a “mixed dentition” stage, a phase lasting until around 12 to 13 years of age when all primary teeth are replaced. By age 21, individuals have a full set of 32 permanent teeth, including incisors, canines, premolars, and molars. The last permanent teeth to emerge are the wisdom teeth, or third molars, which appear between ages 17 and 25, though they may not erupt in everyone.
Nurturing a Healthy Smile from the Start
Caring for a child’s oral health should begin even before the first tooth appears. Gently wiping a baby’s gums with a clean, damp cloth after feedings and before bedtime helps remove food debris and bacteria. This practice also accustoms the baby to an oral hygiene routine. Once the first primary tooth erupts, use a soft-bristled baby toothbrush and a tiny smear of fluoride toothpaste, no larger than a grain of rice, twice a day.
The first dental visit should occur within six months of the first tooth appearing or no later than the child’s first birthday. These early visits allow the dentist to check on tooth development, address concerns, and provide guidance on proper oral care techniques, diet, and habits. Maintaining the health of primary teeth is important as they guide the permanent teeth into their correct positions and help prevent future dental problems.