Dentoalveolar Trauma 6 Flashcards
What are root fractures?
Defined as fractures involving dentin, cementum, and pulp.
How common are root fractures?
Relatively uncommon injury making up only about 0.5 - 7% of injuries to permanent teeth and 2 - 4% of injuries to primary teeth
How do root fractures occur?
Usually frontal impact such as fights and objects striking teeth.
Fracture can occur in different places depending on the direction and distribution of the force
More commonly oblique.
What concurrent injuries accompany root fractures?
Coronal fragment may be concussed, subluxated, extruded, laterally luxated, or avulsed.
Apical fragment often has intact PDL and pulp.
Pulp in coronal fragment may be stretched or lacerated at the fracture line. Rupture and/or compression of the PDL. Root surface may be exposed if the coronal fragment is displaced.
How are root fractures classified?
Apical
Middle
Coronal subdivided into subcretal or supracrestal.
Coronal fragment injury should also be named accordingly.
How are root fractures diagnosed?
History
Clinical observation (coronal segment may be mobile or displaced, bleeding from the gingival sulcus, may have crown discolouration, may be tender to percussion)
Radiographs
Pulp sensibility testing.
Why is pulp testing done for root fractures?
To assess the risk of healing complications. Positive initial pulp test response indicates significantly reduced risk of pulp necrosis.
Initial pulp test is necessary to assess pulp status at subsequent review appointments.
How many radiographs should be taken for root fractures?
Minimum 3 PAs, 1 occlusal and 1 - 2 PAs of opposite arch
This is to diagnose all the injuries.
Which radiographs are best for apical third, middle third, and coronal third root fractures?
Middle + Apical = occlusal
Coronal = Bisecting angle PA.
Some root fractures are not evident initially
Is CBCT useful for root fractures?
No, Not of practical value and unnecessary more radiation.
CBCT can identify injuries to the alveolar bone.
How does the tooth respond to root fractures?
Healing of calcified tissues
Interposition of connective tissue
Interposition of bone and connective tissue
Interposition of granulation tissue
When does healing of calcified tissues occur?
Most likely when no, or little displacement of the coronal fragment
How does healing of calcified tissues occur?
Internal repair of dentine. Usually rounding can be seen in peripheral fracture edges.
Pulp canal calcification is often seen over time
How does interposition of connective tissue occur? When does this occur?
Occurs when coronal segment has been displaced and pulp has been severely stretched or severed completely. PDL cells dominate healing in the fracture line leading to connective tissue repair. (pulp may repair or revascularize if no bacteria are present)
Pulp canal calcification is seen over time
How does interposition of bone and connective tissue occur?
If fracture occurs before completion of alveolar growth the coronal fragment erupts normally while the apical fragment stays in the same position and can get rounding of peripheral fracture edges.
Pulp canal calcification occurs over time
How does interposition of granulation tissue occur?
If the pulp in the coronal fragment necroses and becomes infected, granulation tissue forms in the fracture line in response to the infection. (Similar to apical periodontitis from an infected RCS)
No union between fragments
May be some inflammatory resorption leading to widening of the foramen and the fracture line.
What is the prognosis like for the pulp followign root fracture?
It is very good. Necrosis rate is lower at 26%.
A study of 13 teeth that were incompletely developed there were no lost teeth, external resorption, ankylosis, bone loss, nor pulp necrosis.
In fully developed teeth, Bone loss was seen most commonly in coronal 3rd fractures. Middle third fractures had small percentage of bone loss. Apical third had no bone loss.
What factors affect the prognosis of root fractures?
Age
Stage of root development
Mobility of coronal fragment
Displacement of the coronal fragment
Diastasis between fragments
Treatment provided
It is difficult/impossible to generalize.
What is the rate of pulp canal calcification that was observed following a root fracture?
- 5% after 1 year
- 1% after 3
- 1% after 10
What problems sometimes arise after root fractures?
Bone loss is the most common. Rarely ankylosis and replacement resorption after 10 years.
How common is healing with hard tissue, connective tissue, and granulation tissue in incompletely and completely developed teeth following concussion/subluxation, extrusion, and lateral luxation?
Incomplete:
Subluxation/concussion = 100% hard tissue
Extrusion = 50:50 Hard tissue, connective tissue
Lateral luxation = 100% Hard tissue
Complete:
Subluxation/concussion = 75% hard tissue, 20% connective, and 5% Granulation
Extrusion = 5% hard tissue, 50% connective tissue, and 45% granulation tissue
Lateral luxation = 8% hard tissue, 60% connective tissue, and 32% granulation tissue
MORE GRANULATION TISSUE IN COMPLETE.
How common is pulp canal calcification in root fractures?
Most common in apical third fractures
Common in coronal third root fractures
Less common in middle third
Which root fractures are managed conservatively and which are critical?
Depends on fracture position:
Apical, middle and coronal sub-crestal fracture = Manage conservatively.
Supra-crestal = Critical case.
How are root fractures managed in apical middle and coronal sub-crestal root fractures?
Reposition coronal fragment if dispalced
Stabilise with wire/composite splint (rigid) longer splinting period is better than smaller
Review PDL and pulp healing (If no signs of pulp necrosis continue to review for as long as possible)
Do not start root canal treatment unless there are signs of pulp necrosis.
