Permanent Trauma: Crown fractures

Question 1

What type of patient will typically present with dental trauma?

Answer 1

• Child of 12-13 years of age
• More commonly male than female
• More common in children with an overjet greater than 9mm (especially if they do not have good lip coverage)

Question 2

What is the most common cause of crown fractures?

Answer 2

A direct frontal impact.
E.g. falls, contact spports, RTAs and objects striking teeth.

Question 3

If there is pulp exposure, which factor will worsen treatment prognosis?

Answer 3

• Tooth fracture with pulp exposure results in an intact vascular supply and thus the immunological defense systems can attempt to compact bacterial invasion
• If a luxation injury occurs alongside fracture, vasculairty is compromised or eliminated and bacterial invasion in inevitable

Question 4

What are the aims of treatment after crown fracture?

Answer 4

• Pain relief
• Preservation of vitality
• Promotion of root maturation
• Restoring function and aesthetics

Question 5

What factors determine whether immediate restoration is possible following crown fracture?

Answer 5

• Size of fracture
• Proximity of pulp
• Luxation injury (increased chance of pulp death by 25%)

Question 6

What are the treatment choices for enamel fractures?

Answer 6

• Selective grinding of the incisal edge
• Restoration with composite

Question 7

Why do fractures involving both enamel and dentine always require restoration?

Answer 7

To seal the dentinal tubules and prevent ingress of bacteria and substrates.

Question 8

When is a temporary restoration indicated for a crown fracture?

Answer 8

• Pulpal involvement
• Accompanying luxation injury
• Lack of patient co-operation

Question 9

How could a tooth with a crown fracture be temporarily restored?

Answer 9

• Pre-formed stainless steel or resin crown
• Temporary build-up using a temporary crown and bridge material or GIC

Question 10

In the cases of a complicated crown fracture, what factors influence treatment choice?

Answer 10

• Tooth maturity: if the apex is complete or incomplete (apical formaen diameter greater than 1mm, tooth considered immature and clinical efforts should aim at allowing continued root formation)
• Pulp vitality: tooth must be vital for calcium hydroxide
• Large exposure, old exposure and associated periodontal injury all increase the likelihood of pulp death

Question 11

When is pulp capping indicated for a complicated crown fracture?

Answer 11

Closed apex and vital.
If capping fails, you can extirpate the pulp and root treat.

Question 12

When is a partial pulpotomy indicated for a complicated crown fracture?

Answer 12

Open apex and vital pulp, so long as the amputation site appears red and healthy.
If the site is not healthy, deepen the exposure site until healthy pulp is reached (also includes delayed presentation or dirty wounds).

Question 13

When is a cervical pulpotomy indicated for a complicated crown fracture?

Answer 13

Immature tooth, compromised pulp, dirty wound.
Where the amputation site does not appear healthy.

Question 14

What does a cervical pulpotomy involve?

Answer 14

Removal of coronal pulp, dressed with calcium hydroxide at the point where the crown meets the root.

Question 15

What considerations should be made when treating a complicated crown fracture?

Answer 15

• Use a rubber dam
• An air rotor is used for a pulpotomy, the water supply is not sterile so keep water off and irrigate with plenty of saline

Question 16

Should you see continuing root development following a pulpotomy of a traumatised tooth?

Answer 16

Yes over time you should be able to see root development radiographically.
You may also see signs of dentine being laid down at the pulpotomy site.

Question 17

How does the risk of pulp necrosis and infection increase with periodontal/luxation injury alongisde a crown fracture?

Answer 17

Increased risk from 1-2% (crown fracture only) to 25% (crown fracture with concomitant periodontal/luxation injury)

Question 18

When should an enamel fracture be radiographically reviewed?

Answer 18

6-8 weeks and 1 year post injury

Question 19

When should an enamel and dentine fracture be radiographically reviewed?

Answer 19

6-8 weeks and 1 year post injury

Question 20

When should a crown fracture be radiographically reviewed?

Answer 20

6-8 weeks, 3 months, 6 months and 1 year post injury

Question 21

When should a crown/root fracture be radiographically reviewed?

Answer 21

6-8 weeks, 3 months, 6 months and 1 year post injury + yearly up to 5 years after injury

Question 22

How should crown-root fractures be treated initially?

Answer 22

Aim of the initial appointment is to reduce pain by stabilising the coronal fragment by splinting the fragment to adjacent teeth.

Question 23

What are the 3 long-term treatment options for a crown-root fracture?

Answer 23

• Removal or coronal fragment and supragingival restoration
• Removal of coronal fragment and gingivectomy and/or osteotomy (converts subgingival fracture to supragingival)
• Removal of coronal fragment and surgical or orthodontic extrusion of the root (to move fracture surface to more optimal location for definitive restoration)