Knocked-out tooth

Definition

A knocked-out tooth, or dental avulsion, occurs when a tooth is completely displaced from its socket due to trauma. It is considered a dental emergency because prompt and correct management is critical for preserving the tooth’s viability, particularly in permanent teeth.

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Epidemiology

• More common in children and young adults engaged in sports or activities with high risk of facial injury.

• Permanent anterior teeth, especially upper central incisors, are most often affected.

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Causes

• Sports-related injuries (football, basketball, hockey).

• Falls or accidents.

• Physical altercations.

• Bicycle or motor vehicle collisions.

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Pathophysiology

• Avulsion disrupts the periodontal ligament and blood supply to the tooth.

• Rapid reimplantation or proper storage is crucial to maintain viability of periodontal ligament cells and prevent root resorption or ankylosis.

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Clinical Presentation

Signs and Symptoms

• Missing tooth with an empty socket.

• Bleeding from the socket.

• Soft tissue swelling or lacerations.

• Pain in the affected area.

• Possible adjacent tooth damage.

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Immediate First Aid Management

1. Handle the Tooth Correctly

• Hold the tooth only by the crown (the chewing surface), not by the root, to prevent damage to periodontal ligament cells.

2. Cleaning the Tooth

• If dirty, gently rinse with saline or milk for a few seconds.

• Avoid scrubbing, scraping, or using soap/disinfectants.

3. Reimplantation (Preferred if Possible)

• For permanent teeth only:

  • Gently reinsert the tooth into its socket, ensuring correct orientation.

  • Ask the patient to bite on gauze to hold it in place.

4. Storage if Reimplantation Not Possible

• Place in Hank’s Balanced Salt Solution (HBSS) (ideal).

• If unavailable: store in cold milk, saliva (buccal vestibule), or saline.

• Avoid dry storage; periodontal ligament cells begin dying within minutes.

5. Seek Emergency Dental Care Immediately

• Optimal reimplantation within 15–30 minutes for best prognosis.

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Professional Emergency Management

1. Reimplantation Procedure

• Verify tooth type (permanent vs deciduous — do not reimplant primary teeth).

• Irrigate socket with sterile saline.

• Gently reinsert tooth into socket.

2. Splinting

• Flexible splint (wire and composite) applied to stabilize tooth for 2 weeks (up to 4 weeks if severe trauma).

3. Tetanus Prophylaxis

• Tetanus toxoid booster if vaccination status incomplete or injury contaminated.

4. Antibiotic Therapy

• Amoxicillin: 500 mg orally every 8 hours for 5–7 days (children: 40 mg/kg/day divided every 8 hours).

• Phenoxymethylpenicillin: 500 mg orally every 6 hours for 5–7 days.

• For penicillin allergy: Doxycycline 100 mg orally once daily for 7 days (avoid in children under 12 years).

5. Pain Management

• Paracetamol: 500–1,000 mg orally every 4–6 hours (max 4 g/day).

• Ibuprofen: 200–400 mg orally every 6–8 hours (max 2,400 mg/day under supervision).

6. Endodontic Considerations

• Root canal treatment usually within 7–10 days after reimplantation in mature permanent teeth to prevent infection-related resorption.

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Special Considerations

• Primary (baby) teeth:

  • Do not reimplant due to risk of damaging the permanent tooth bud.

  • Manage bleeding and refer to dentist for monitoring.

• Delayed reimplantation (>60 minutes dry time):

  • Prognosis poor, but reimplantation may still be attempted for aesthetic and functional reasons.

  • Expect root resorption and eventual tooth loss.

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Complications

• Root resorption (inflammatory or replacement).

• Ankylosis (fusion of tooth to bone).

• Tooth discoloration.

• Pulp necrosis.

• Infection.

• Tooth loss.

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Prognosis

• Best outcomes occur when the tooth is reimplanted within 15–30 minutes.

• Proper storage and minimal root handling improve survival rates.

• Delayed care significantly reduces long-term retention.