What should one do with an avulsed (knocked-out) tooth to potentially save it?

Re-implanting an avulsed tooth promptly is the most effective action to potentially save the tooth. When a tooth is knocked out, the periodontal ligament cells that support the tooth can quickly begin to die if the tooth is not kept in a proper environment. By re-implanting the tooth, ideally within 30 minutes, you can provide the necessary support and saliva environment, which can help preserve the viability of the ligament cells.

If re-implantation is not immediately possible, keeping the tooth moist is vital for preservation. The best options for keeping a tooth viable are placing it back into its socket if the person can do so comfortably, or submerging it in a nutrient-rich solution like saliva or a glass of milk. This supports the tooth's cellular health.

Using ice, leaving the tooth out, or placing it in sugar water do not provide the necessary conditions to preserve the tooth or support the periodontal cells. Instead, they can lead to dehydration, which further complicates the possibility of successful reinsertion. Hence, re-implantation is the recommended action to maximize the chance of saving the tooth.