What first action is critical when encountering an avulsed tooth?

The critical first action when encountering an avulsed tooth is to re-implant it immediately, provided that the circumstances allow for it. This action is essential because re-implanting the tooth quickly increases the chances of saving the tooth by maintaining the vitality of the periodontal ligaments that support it. The sooner a tooth is re-implanted, ideally within 30 minutes, the better the prognosis for successful reintegration into the dental arch.

In cases where immediate re-implantation is not possible, it's important to preserve the tooth in a suitable medium, such as milk or saline, to maintain the necessary moisture and prevent the tooth from drying out. Additionally, avoiding rinsing the tooth with mouthwash or cleaning it with soap and water is crucial, as these actions can damage the delicate cells on the tooth root that are vital for re-attachment.