Pediatric Dentistry · patient case with 1 question
Avulsion after a diving accident
Patient: Female, 44 years old
Chief complaint: “I hit my chin on the ground diving into the pool.”
History: No relevant medical history. Injury occurred 20 minutes ago.
Findings: Maximum mouth opening 20 mm. Mandible deviates to the right on opening. Tooth #8 avulsed and brought in by a bystander. Teeth #24 and #25 have crown fractures.
Question 1
If the tooth cannot be replanted at the scene, which is the most appropriate storage medium for tooth #8?
Show answer and explanation
Correct answer: B. Milk
- A. Saliva keeps the tooth moist and is an acceptable emergency option — in the buccal vestibule if there is no aspiration risk — but its osmolality and bacterial load limit viability to roughly 30 to 60 minutes.
- B. CORRECT. The objective is to keep the periodontal ligament cells on the root surface ALIVE. MILK is the best practical medium: it is close to physiologic osmolality so cells neither swell nor shrink, it has a near-neutral pH, it contains nutrients and growth factors, it is relatively free of bacteria, and — the reason it is the standard answer — it is available almost everywhere. It maintains cell viability for around six hours.
- C. Dry storage is the most damaging of all. PDL cells begin dying within 15 to 20 minutes, and beyond 60 minutes dry time the prognosis is poor, with replacement resorption and ankylosis the expected outcome.
- D. Tap water is the WORST liquid medium. It is hypotonic, so PDL cells absorb water, swell and lyse within minutes. Water is worse than dry storage for short intervals.
Note: The IADT ranking: replant at the scene if at all possible, otherwise Hank's Balanced Salt Solution, then milk, then saliva, then a physiologic saline. Extra-oral DRY time is the single strongest predictor of outcome. In this vignette, note also the 20 mm opening with deviation — that pattern warrants imaging for a condylar fracture.