The presence of what is commonly called “shark teeth” in an adult is medically known as retained primary teeth. This condition occurs when one or more deciduous teeth fail to naturally exfoliate and remain in the mouth after the permanent teeth have erupted. Persistence into adulthood indicates an underlying developmental issue requiring professional assessment. A multidisciplinary approach, typically involving a general dentist, an oral surgeon, and an orthodontist, is necessary to determine the correct diagnostic and treatment pathway.
Why Primary Teeth Persist into Adulthood
The primary reason a baby tooth remains is the congenital absence of its permanent successor, known as hypodontia. When the adult tooth bud fails to form, the primary tooth root does not undergo the normal process of resorption. Without this trigger, the primary tooth remains anchored in the jawbone.
Another significant cause is ankylosis, the fusion of the tooth root directly to the alveolar bone. This abnormal connection eliminates the periodontal ligament, preventing the tooth from moving or shedding, and often results from trauma or infection. An ankylosed tooth appears “submerged” or lower than adjacent teeth because it stops moving while the jawbone continues vertical growth. Misalignment of the permanent tooth can also cause persistence if the erupting tooth fails to contact and resorb the primary tooth root correctly.
Retaining a primary tooth can lead to several complications, including the tipping or drifting of adjacent permanent teeth, causing crowding and malocclusion. The retained tooth may also become a plaque trap, increasing the risk of periodontal disease and root damage to neighboring teeth. The limited root structure of a primary tooth may not withstand chewing forces, often making extraction necessary.
Initial Treatment: Removal of the Retained Tooth
The first step in correcting retained primary teeth involves a thorough diagnostic process, including a clinical examination and advanced imaging like a Cone-Beam Computed Tomography (CBCT) scan. This three-dimensional imaging allows the surgical team to precisely assess the tooth’s root structure, determine if ankylosis is present, and identify the location of any unerupted permanent teeth or nearby nerves. Extraction of the retained tooth is often necessary to prevent further complications and prepare the jaw for proper alignment.
For non-ankylosed primary teeth, removal is generally a simple extraction performed under local anesthesia. If the tooth is ankylosed, the extraction becomes a more involved surgical procedure, as the fused bone must be carefully separated from the root. In these cases, the surgeon may need to section the tooth into smaller pieces or use bone guttering to remove surrounding bone before removal.
A consideration immediately following extraction is the preservation of the alveolar bone ridge, particularly if the treatment plan includes future implant placement. The tooth socket may be immediately grafted with bone substitute material to prevent the collapse of the bone that occurs after tooth removal. This step ensures sufficient bone volume remains to support a potential dental implant or maintain space for orthodontic movement. Post-extraction recovery involves standard care, managing minor swelling or discomfort, and is generally completed within one to two weeks.
Correcting Alignment and Bite Issues
Once the retained tooth is removed and the extraction site has healed, the secondary phase focuses on managing the created space and correcting any existing malocclusion. This phase is handled by an orthodontist who uses specialized appliances to guide adjacent permanent teeth into their correct positions. The treatment goal is to achieve both functional stability and optimal aesthetic alignment of the entire dental arch.
Treatment options include traditional fixed braces, which use brackets and wires to control tooth movement, or clear aligner therapy, which uses a series of custom-made, removable trays. The choice depends on the complexity of the required tooth movements and the patient’s preference and compliance. If the permanent successor tooth is impacted, the orthodontist may attempt to expose it surgically and then apply light force to bring it into the dental arch.
Because the adult jawbone is mature, tooth movement occurs more slowly compared to adolescents. The active phase of orthodontic treatment typically lasts between 12 and 36 months, depending on the severity of the original alignment issue. After the active movement phase is complete, a retention phase is mandatory to prevent the teeth from shifting back toward their original positions. This involves the long-term use of retainers, such as custom-fitted plastic appliances or thin wires bonded discreetly to the back surfaces of the teeth.