Permanent Trauma: Root fractures

Question 1

How common are root fractures?

Answer 1

Uncommon, account for approximately 7% of dental injuries.

Question 2

Which teeth are most commonly affected by root fractures and what age do these patients tend to be?

Answer 2

• Upper central incisors most common
• Typical patient aged between 11-20

Question 3

How are root fractures loosely categorised?

Answer 3

• Cervical third
• Mid third
• Apical third

Question 4

What type of trauma usually results in a root fracture?

Answer 4

Horizontal, frontal impact.

Question 5

If the coronal fragment is displaced, which direction does it typically move in?

Answer 5

Palatal direction (extruded).

Question 6

What factors determine root fracture healing?

Answer 6

• Whether pulp is severed or not
• Whether bacteria have invaded fracture line or not
• The level of the fracture: more coronal fracture line increases likelihood of mobility, more difficult healing
• The degree of displacement of the coronal fragment

Question 7

What treatment does Andreasen recommend for root fractures?

Answer 7

• Sensibility testing and radiographic follow up, RCT may be required
• If mobility is greater than grade 1, the displaced coronal fragment should be repositioned and splint applied for 3 weeks
• After 3 weeks the PDL has normally stablised the tooth
• Permanent fixation usually required in the form of a fixed retainer for cervical third fractures
• Alternatively, the coronal fragment may be extracted, the root portion root-filled and a post-crown placed

Question 8

What are the 3 possible consequences of root fractures?

Answer 8

• Pulp death/pulp obliteration
• Progressive root resorption (indicative of normal healing, does not require treatment but should be monitored- 60% prevalence)
• Resorption within the bone (indicative of pulp necrosis, requires RCT- rare)

Question 9

What factors are more commonly associated with pulp necrosis following fracture?

Answer 9

Pulp necrosis is more common when there has been displacement of the coronal fragment, and where there is mature root formation.

Question 10

If pulp necrosis occurs, as indicated radiographically by resorption of bone at the level of the fracture, what should you do?

Answer 10

Extripate the pulp to level of the fracture and use calcium hydroxide as an interim dressing for 2 weeks.
Then perform definitive obturation with GP, using MTA as the ‘apical stop’ at the fracture level.