Crown Fractures

Question 1

What type of trauma usually results in crown fracture?

Answer 1

A direct frontal impact

Question 2

What are most common aetiological factors of a crown fracture?

Answer 2

Falls, contact sports, road traffic accidents, and objects striking teeth

Question 3

What features might you expect “typical” patient presenting with this type of trauma to have?

Answer 3

Boys presumably due to an increase in sporting injuries and individuals with increased overjets especially if they do not have good lip coverage

Question 4

What might you expect to be predisposing factors to dental trauma?

Question 5

What are aims of treatment?

Answer 5

Pain relief, preservation of vitality, promotion of root maturation, restoring function and aesthetics

Question 6

What factors determine whether or not a tooth can be restored immediately?

Answer 6

Size of fracture and proximity of pulp

Question 7

What is risk of pulp death where a periodontal/luxation injury has also occurred?

Answer 7

25%

Question 8

What is another source of irritation to a pulp that has already been insulted?

Answer 8

Acid etchant

Question 9

What is management of enamel fractures?

Answer 9

Composite resin build-up or reattachment of crown fragment

Question 10

What should all fragments be stored in?

Answer 10

Physiologic saline/tap water until bonding to prevent discoloration and/or infractions due to dehydration

Question 11

What is restoration of uncomplicated fractures and no con-comitant luxation injury?

Answer 11

Bonding can be performed immediately

Question 12

What is restoration of concomitant luxation injury with tooth displacement?

Answer 12

A period of temporary restoration, corresponding to splinting period after luxation

Question 13

What is temporisation?

Answer 13

To create provisional restorations that are required in short- or mid-term

Question 14

What is temporisation in uncomplicated fractures?

Answer 14

Exposed fracture surface (enamel and dentin) is disinfected and then covered with a glass ionomer cement

Question 15

What is temporisation in complicated fractures?

Answer 15

Pure calcium hydroxide is placed over exposure and enamel and dentin of fracture surface are then covered with glass ionomer cement

Question 16

What is temporisation in concomitant luxation injuries?

Answer 16

Temporary restoration should stabilise fractured tooth in order to avoid migration of injured incisor/its antagonists

Question 17

What are conditions for pulp capping and partial pulpotomy?

Answer 17

Tooth should have been free of inflammation prior to injury and any associated injury to PDL must not have compromised vascular supply

Question 18

What should pulp capping be primarily used for?

Answer 18

Small exposures soon after injury (possibly within first 24 hours) and where a restoration can be placed which provides a tight seal against bacterial invasion

Question 19

What should pulpotomy be primarily used for?

Answer 19

Longer post-trauma intervals to a depth of 2mm

Question 20

What should amputation site be covered with?

Answer 20

Either hard setting calcium hydroxide cement followed by a thin layer of glass ionomer cement/MTA and tooth restored using a dental adhesive to ensure a bacteria-tight seal

Question 21

What are follow-up procedures for crown fractured teeth?

Answer 21

1 and 2 months and 1 year after injury

Question 22

What are signs of pulp necrosis?

Answer 22

Loss of pulpal sensibility, coronal discolouration, and periapical radiolucency and persistent tenderness to percussion

Question 23

What are key features when determining appropriate treatment?

Answer 23

Tooth maturity, pulp vitality, associated periodontal injury, size of exposure, and age of exposure

Question 24

What is tooth maturity?

Answer 24

Does tooth have a completed apex?

Question 25

When is a tooth considered immature?

Answer 25

If apical foramen is greater than 1mm in diameter on periapical radiograph

Question 26

What increases chance of pulp death?

Answer 26

Large exposures, old exposures and associated periodontal injuries

Question 27

What must pulp be if it is to respond to calcium hydroxide therapy?

Answer 27

Vital

Question 28

When should pulp capping be carried out?

Answer 28

Closed apex, provided pulp is vital i.e. looks red and healthy/positive vitality test

Question 29

What should you do if cap falls off?

Answer 29

If pulp cap fails you can always extirpate pulp and root treat, thus clean injuries within 24 hours

Question 30

When should partial pulpomoty be carried out?

Answer 30

Open apex, vital pulp, provided amputation site looks red and healthy

Question 31

What should you do if amputation site does not look red and healthy?

Answer 31

Exposure site should be deepened until healthy pulp is reached

Question 32

When should cervical pulpotomy be carried out?

Answer 32

Immature tooth, compromised pulp, and dirty wound

Question 33

What is treatment where amputation site does not look healthy?

Answer 33

Still prefer to use this older technique where you remove coronal pulp and dress with calcium hydroxide at point where crown meets root

Question 34

What instrument is used for a pulpotomy?

Answer 34

Air rotor

Question 35

What is water supply in an air rotor?

Answer 35

Not sterile, it is also a hypotonic solution

Question 36

How can water supply in air rotor become an isotonic solution?

Answer 36

Turn it off and irrigate with saline, use lots of it

Question 37

What material is preferred when dressing wound?

Answer 37

Hard setting calcium hydroxide

Question 38

What is pulp capping procedure?

Answer 38

Isolate pulp exposure, cover pulp with a calcium hydroxide material (either hard-setting cement/pure calcium hydroxide paste), restore tooth immediately with a bacteria-tight restoration, later assessment of hard tissue barrier implies risk of renewed exposure to bacteria, thereafter, hard tissue barrier is re-covered with glass ionomer cement/a composite resin retained with a dental bonding agent; and thereafter tooth can be restored

Question 39

What is pulpotomy procedure?

Answer 39

Isolate pulp exposure, amputate pulp to a level approximately 2 mm below exposure site/to where fresh bleeding is seen, if immediate restoration is desired, cover exposure with a hard-setting calcium hydroxide cement (e.g. Dycal/Life), if later assessment of hard tissue barrier is desired, cover exposure with pure calcium hydroxide paste, cover entire fracture surface (enamel and dentin) with a hard-setting calcium hydroxide cement and a temporary restoration for a period of 3 months, at that time, uncover amputation site, remove necrotic pulp tissue immediately above hard tissue barrier and restore with a bacteria-tight restoration