Best Review Articles

1. Gartshore L, Haq T, Djemal S. "Endodontic implications of dental trauma: useful tips for primary dental care." Br Dent J. 2025 Apr. PMID: 40217037 - This is the most clinically practical and up-to-date review covering all major sequelae with incidence data and management pointers.
2. Abbott PV. "Indications for root canal treatment following traumatic dental injuries to permanent teeth." Aust Dent J. 2023;70(2). PMID: 37908151 - A focused review on when each complication warrants RCT.
3. Tewari N et al. "Risk of pulp necrosis and related complications in permanent anterior teeth with lateral luxation: A systematic review and meta-analysis." Dent Traumatol. 2024 Oct. PMID: 38576393 - Quantifies complication risk by injury type.
4. Thelen DS et al. "Pathophysiological mechanisms of root resorption after dental trauma: a systematic scoping review." BMC Oral Health. 2021. Springer Link - Deep mechanistic review of root resorption subtypes.

Sequelae of Trauma to Permanent Teeth

1. Pulp Necrosis

• Severance or stretching of the neurovascular bundle at the apex interrupts pulp blood supply
• Can be sterile (immediately post-avulsion) or infected (bacterial ingress via enamel infractions, restoration microleakage, or root dentine)
• Infected necrosis is the critical driver of further complications - bacterial toxins penetrate dentinal tubules and damage root cementum

2. Pulp Canal Obliteration (PCO)

• The pulp responds to trauma by depositing tertiary/reparative dentine, progressively narrowing or obliterating the root canal
• Clinically the tooth may appear yellow-brown (most common discolouration after luxation injuries)
• Radiographically: narrowing or complete loss of canal shadow
• Reported in 4-24% of luxated teeth - most common after concussion and subluxation
• The key question: PCO does not always mean the pulp is necrotic. However, approximately 1-7% of teeth with PCO will eventually develop pulp necrosis, so periodic radiographic review is mandatory
• Prophylactic RCT is not indicated; treat only if necrosis is confirmed

3. Root Resorption

a) Surface Resorption

• Transient, self-limiting
• Results from superficial PDL damage
• Heals spontaneously with cementoblast repopulation
• No clinical or radiographic significance

b) Inflammatory Root Resorption (External)

• Driven by combined injury to pulp + root cementum (especially luxation injuries)
• Requires: (1) pulp necrosis with intracanal infection AND (2) cementum damage exposing dentinal tubules
• Bacterial toxins diffuse through tubules, activating osteoclast-like clastic cells
• Rapidly progressive - can destroy an entire root within weeks to months if untreated
• Radiographically: irregular "moth-eaten" root surface with adjacent bone destruction
• Inflammatory mediators: IL-1α, IL-1β, TNF-α elevated in gingival crevicular fluid
• Treatment: urgent RCT with calcium hydroxide to neutralise infection and arrest resorption

c) Replacement Resorption (Ankylosis)

• Complication of avulsion (most common), severe intrusion, or dry extra-oral time
• Damaged PDL cells are replaced by bone directly fusing to the root surface
• Clinically: high metallic sound on percussion (characteristic finding)
• Radiographically: loss of PDL space, direct bone-root contact, progressive root shortening
• In growing children: infra-occlusion develops as the ankylosed tooth fails to erupt with alveolar growth
• No effective treatment once established - management is monitoring, decoronation in growing patients to preserve alveolar bone height, and eventual implant planning
• Incidence: up to 50% after avulsion

d) External Cervical Resorption

• Initiated at the cervical region below the epithelial attachment
• Associated with trauma history, orthodontic treatment, internal bleaching
• Invasive resorption that can be mistaken for caries or internal resorption

e) Internal Resorption

• Uncommon after trauma; arises from a vital but chronically inflamed pulp
• Radiographically: round/oval symmetric widening of canal within the root
• Managed with RCT before perforation occurs

4. Tooth Discolouration

• Yellow/brown (PCO): Most common after concussion/subluxation; due to obliterative calcification - pulp usually vital
• Grey/black (pulp necrosis): Due to breakdown of haemoglobin and haemosiderin from pulp haemorrhage dispersing into dentinal tubules; indicates necrosis - requires investigation
• Pink (internal resorption or external cervical resorption): Less common; "pink spot" reflects vascular granulation tissue visible through thinned crown

5. Periodontal Complications

• PDL injury after intrusion/avulsion can result in loss of the PDL scaffold
• Marginal bone loss may follow severe luxation if not managed properly
• Gingival recession can occur after lateral luxation

6. Development Disturbances (if trauma during root development)

• Arrest of root formation if Hertwig's epithelial root sheath is damaged
• Open apex (immature tooth): increases risk of pulp necrosis but also allows pulp revascularisation - immature teeth paradoxically have better revascularisation potential than mature teeth
• Regenerative endodontic protocols (revascularisation/REPs) are indicated for immature permanent teeth with pulp necrosis

7. Tooth Loss

Summary Table: Sequelae by Injury Type