A knocked-out tooth occurs when it is completely dislodged from its socket due to trauma. While alarming, successful re-implantation is often possible, depending significantly on prompt actions taken immediately after the incident.
Immediate Actions for an Avulsed Tooth
When a permanent tooth is dislodged, swift action greatly influences replantation success. First, locate the tooth and carefully pick it up by the crown, avoiding touching the root. If dirty, gently rinse it with water or milk for a few seconds; do not scrub or use soap, as this can damage delicate root surface cells.
After rinsing, gently reinsert the tooth back into its socket, ensuring it faces the correct way. If it slides in easily, bite down gently on a clean cloth or gauze to hold it in place. If immediate reinsertion is not feasible, the tooth must be kept moist. Suitable storage mediums include milk, saline solution, or saliva (e.g., holding it in the cheek or spitting into a container).
Avoid storing the tooth in regular tap water, as its composition can harm root surface cells. Seek immediate professional dental care. Successful reattachment is most likely when the tooth is replanted within 30 to 60 minutes of injury.
The Science Behind Replantation Success
The viability of a replanted tooth depends on the health of periodontal ligament (PDL) cells, which cover the tooth’s root surface. These cells are essential for the tooth to reattach to the bone within the socket. When a tooth is avulsed, the PDL is stretched and torn, making its cells susceptible to damage and drying out.
Maintaining these cells in a moist and physiologically compatible environment is important. Dry conditions, even for short periods, can cause irreversible damage to PDL cells, leading to complications like root resorption after replantation. Storage mediums like milk or Hank’s Balanced Salt Solution (HBSS) help preserve cell viability due to their appropriate pH and osmolality.
Prompt action minimizes extra-oral dry time. Replantation within 15 minutes offers the best prognosis for PDL cell survival and successful healing. Even if immediate replantation is not possible, proper storage extends the window of opportunity by protecting these cells.
Professional Dental Care and Long-Term Outlook
Upon reaching the dental office, the dentist will assess the tooth and socket for damage or debris. The socket will be gently irrigated with saline solution before the tooth is carefully reinserted into its original position.
Once replanted, the tooth is typically stabilized using a temporary splint, which anchors it to adjacent teeth. This splint holds the tooth in place while surrounding tissues heal, usually remaining for two to six weeks. Following replantation, root canal treatment is often necessary, especially for fully developed permanent teeth, because blood vessels and nerves inside the tooth are typically severed during avulsion. This procedure removes the damaged pulp to prevent infection.
The long-term success of a replanted tooth depends on factors like replantation speed, storage conditions, and initial PDL damage. While some replanted teeth function for many years, complications such as root resorption or ankylosis (fusion of the tooth root to the bone) can occur. Regular follow-up appointments are important to monitor healing and address potential issues.
Preventing Tooth Avulsion
To reduce the risk of a tooth being knocked out, wear a mouthguard during sports and physical activities with a risk of facial impact. Custom-fitted mouthguards, made by a dentist, offer the best protection and comfort.
Boil-and-bite mouthguards provide some protection and are a more accessible option, though they may not fit as securely as custom-made ones. Beyond sports, avoid chewing on hard objects like ice or hard candies, which can weaken teeth. Maintaining awareness of surroundings during activities that might pose a risk of falls can also help prevent dental injuries.