Preserving an extracted wisdom tooth involves safely cleaning biological material and stabilizing the tooth’s structure. The tooth is composed of three main calcified tissues: the outer enamel, the underlying dentin, and the cementum covering the root surface. Since the tooth is removed from the body, it is initially considered a biohazard. The removal of soft tissue and thorough disinfection are necessary to transform the specimen into an inert object suitable for long-term keeping.
Initial Removal of Soft Tissue
The first step is to remove all visible blood, clots, and gross debris by rinsing the tooth under running water. This initial rinse should be thorough to wash away large, loose contaminants from the surface of the enamel and roots. Wear gloves and use a catch basin or sieve to prevent the tooth from being lost down the drain during this initial cleaning.
Next, focus on the periodontal ligament and any attached gingival tissue adhered to the cementum layer on the root. These remnants of connective tissue must be removed to prevent subsequent discoloration and decay. Use a small, soft-bristled toothbrush, mild soap, and warm water to gently scrub the entire surface of the tooth, paying close attention to the crevices between the roots.
For stubborn pieces of tissue, a small tool like a wooden toothpick or a dedicated dental pick can be used to meticulously scrape the root surfaces. This physical removal process requires patience and a light touch to avoid gouging the softer cementum or scratching the harder enamel surface. This mechanical cleaning eliminates the bulk of the organic matter before chemical disinfection.
Chemical Cleaning and Disinfection
After removing the soft tissue, a chemical soak is necessary to fully disinfect the tooth and dissolve any remaining microscopic organic material. Immerse the tooth in a dilute solution of household bleach, which contains sodium hypochlorite. This chemical acts as a powerful disinfectant and tissue solvent, helping to whiten the tooth by breaking down organic residue.
A recommended mixture is a 1:10 solution, combining one part household bleach with nine parts water. The tooth should be completely submerged in this solution within a sealed container for at least 24 hours to ensure adequate disinfection. For specimens with significant staining, a longer soak, potentially up to a few days, may be necessary to fully clear the root canals and porous dentin structure.
Handle the bleach solution in a well-ventilated area and wear protective gloves and eyewear to prevent chemical burns or irritation. Following the bleach soak, the tooth must be rinsed thoroughly under running water for several minutes to wash away all traces of the sodium hypochlorite. Failure to rinse completely can lead to long-term structural changes or brittleness in the dentin, the bulk of the tooth structure.
To enhance the tooth’s aesthetic appearance, particularly for a whitening effect, a soak in 3% hydrogen peroxide can be used. Hydrogen peroxide is a mild bleaching agent that helps remove residual staining not lifted by the bleach. Submerging the tooth in this solution for several hours or overnight is generally sufficient to brighten the color before the final preservation process begins.
Final Steps for Preservation and Display
Once the tooth has been thoroughly cleaned, disinfected, and rinsed, it must be completely dried before final preservation. Residual moisture trapped within the porous dentin and cementum could encourage the growth of mold or bacteria over time. A minimum air-drying period of 24 to 48 hours is recommended in an open, dry environment away from direct heat or intense sunlight.
After the specimen is completely dry, applying a protective coating helps to seal the surface, preventing future discoloration and adding a subtle luster. A clear sealant, such as clear acrylic spray, polyurethane lacquer, or clear nail polish, can be carefully painted onto the entire surface of the tooth. This sealant layer creates a physical barrier, ensuring the long-term stability of the specimen.
The final preserved tooth can then be prepared for display in a manner that protects it from physical damage and dust. Options range from embedding the tooth in clear casting resin to creating a simple display in a shadow box or a small, corked glass jar. These final steps stabilize the tooth, allowing for safe and lasting observation.