When children begin to lose their baby teeth, parents often encounter permanent teeth emerging behind the existing baby teeth. This phenomenon, commonly referred to as “shark teeth” due to the appearance of a double row of teeth, is a frequent concern. Understanding this common dental development can alleviate worry, as it is a relatively common occurrence during a child’s transition from primary to permanent dentition.
The Normal Transition from Baby to Permanent Teeth
The natural process of tooth shedding and eruption is a biological event. Baby teeth serve as placeholders and guides for the permanent teeth that will follow. As a permanent tooth develops beneath the gum line, it pushes upward against the root of the baby tooth. This pressure triggers root resorption, where the baby tooth’s roots slowly dissolve.
As the baby tooth’s roots resorb, it becomes increasingly loose and eventually falls out, creating space for the permanent tooth to emerge into its correct position. This process begins around age six and continues until approximately age 12 or 13 when most baby teeth have been replaced. A child’s jaw and facial bones also grow during this period, providing ample space for the larger permanent teeth.
Why Permanent Teeth Emerge Behind Baby Teeth
The appearance of permanent teeth behind baby teeth occurs when the baby tooth’s root does not resorb properly. Instead of the permanent tooth pushing upward and dissolving the baby tooth’s root, it erupts slightly off-center. This leaves the baby tooth firmly in place while the new tooth finds an alternative path into the mouth.
This timing mismatch between the eruption of the permanent tooth and the shedding of the baby tooth is a common reason for “shark teeth.” The permanent tooth buds develop on the tongue side of the baby teeth, and if the baby tooth’s root does not dissolve, the permanent tooth has no clear path. Other factors like crowding or a lack of space in the jaw can also contribute to permanent teeth erupting in an atypical position. Extra teeth or an abnormal position of the tooth bud during development can also lead to this phenomenon.
When to Be Concerned and What to Do
If the baby tooth is already loose, the situation may resolve naturally. The tongue’s natural pressure can help guide the newly erupted permanent tooth forward into its correct alignment once the baby tooth falls out. Encouraging a child to gently wiggle a loose baby tooth can assist in this natural process.
Dental intervention becomes necessary in certain circumstances. If the baby tooth remains firm and shows no signs of loosening within a couple of months after the permanent tooth has emerged, a dental professional should be consulted. A dentist might recommend extracting the baby tooth to create space and allow the permanent tooth to move into its proper position. Professional guidance is advisable if the permanent tooth causes discomfort, if there is misalignment, or if “shark teeth” appear in the molars, as these can be more problematic than in the thinner front teeth.
Long-Term Implications
Leaving a permanent tooth erupting behind a baby tooth unaddressed can lead to complications for dental development. If the baby tooth is not removed, it can obstruct the permanent tooth’s natural path, forcing it to remain in an incorrect position. This can result in crowding or misalignment of the permanent teeth.
Such issues may necessitate orthodontic treatment, such as braces or other dental appliances, to correct alignment and ensure a healthy bite. Misaligned teeth can also make effective oral hygiene more challenging, increasing the risk of plaque buildup, cavities, and gum disease. Unaddressed misalignment can lead to impacted teeth, where a tooth remains trapped beneath the gum line, or issues with jaw function. Timely intervention helps ensure optimal dental health and development.