Mixed Dentition Trauma

Question 1

what are the principles of luxation injury management

Answer 1

1. Reposition (take repositioning x ray to verify position before splinting, tooth should be in socket)
2. Fixation (splint)
3. Endo monitoring – pulpal and perio status

Question 2

what are the objectives of splinting a tooth following luxation injury

Answer 2

Stabilise the tooth to optimise healing outcomes for pulp and PDL esp during function

Improve function, provide comfort

Question 3

if there is breakdown of marginal bone or alveolar socket wall, splint for __ (duration)

Answer 3

additional 4 weeks

Question 4

Lateral luxation of permanent tooth clinical presentation of young permanent tooth

Answer 4

often immobile, apex is locked in by bone fracture

highly metallic (ankylotic) sound when you percuss

no response to pulp sensibility testing

Question 5

When do you make endodontic evaluation following luxation injury of young permanent tooth

Answer 5

2 weeks post evaluation

Question 6

compare the outcomes following lateral luxation of tooth with incomplete root formation and complete root formation

Answer 6

Spontaneous revascularisation may occur in tooth with incomplete root formation, while there is increased risk of pulp necrosis due to pulp strangulation or luxation in tooth with complete root formation

Question 7

After lateral luxation of young permanent tooth, negative response to pulp sensibility testing. no other signs and symptoms of loss of vitality. when do you start RCT?

Answer 7

False negative may be possible for several months. should not start endodontic treatment solely based on no response to pulp sensibility testing

Question 8

unfavourable outcome of lateral luxation of young permanent tooth

Answer 8

Pulp necrosis and infection 
Ankylosis
External inflammatory infection related resorption 
External replacement resorption 
Apical periodontitis
Break down of marginal bone
Symptomatic

Question 9

what can you to help prevent inflammatory type root resorption in young permanent teeth

Answer 9

calcium hydroxide or corticosteroid antibiotic intracanal medicament, initiation of root canal treatment

Question 10

with root injuries, you are worried about

Answer 10

inflammatory resorption and replacement resorption

Question 11

what is replacement resorption

Answer 11

osteoclastic action eats up the tooth. loss of pdl space as bone replaces root

Question 12

what is the short term, medium term, long term management following trauma of young permanent teeth

Answer 12

short term:
pulp extirpation 2 weeks post trauma, initiate rct 4 weeks post trauma with splint kept on

medium term:
restore aesthetics, prevent mesial drift, monitor for healing after splint removal

long term:
monitor for root resorption

Question 13

possible sequelae of incisal trauma young permanent teeth

Answer 13

loss of vitality
ankylosis/replacement resorption
internal and external root resorption
pulpal calcification and obliteration

Question 14

Rank injuries in terms of risk of pulp necrosis to young permanent teeth

Answer 14

in decreasing order

1. Avulsion
2. Intrusion
3. Luxation, extrusion
4. Concussion, subluxation

concomitant injury eg luxation with concomitant crown fracture –> higher risk of pulp necrosis

Question 15

how does inflammation resorption occur after trauma

Answer 15

during trauma, protective layer ie pre cementum is damaged. pulp or pdl cell necrosis sustain inflammation around the root, inflammatory response result in root resorption

Question 16

why does focal/surface resorption occur

Answer 16

mild injury eg subluxation, mild extrusion –> PDL cells still viable. hence cemental healing can occur, end up with focal surface resorption

Question 17

post trauma pulp canal obliteration tends to occur in what kind of teeth (age)

Answer 17

immature permanent teeth with wide open apex

Question 18

consequences of pulp canal obliteration

Answer 18

may cause pulp strangulation and hence loss of vitality

endodontic treatment difficult as cannot visualise the space

orthodontic movement of tooth with pulp canal obliteration increases risk of tooth becoming non vital due to slender neurovascular bundle

Question 19

how to describe root fractures

Answer 19

number
level eg mid root, apical third
direction eg horizontal, oblique
mobility/point of rotation 
degree of separation

Question 20

how does degree of separation related to pulpal death

Answer 20

mm. greater degree, higher risk of pulp death

Question 21

Cervical fracture of young permanent tooth. Coronal fragment not mobile. What should you do at the emergency visit?

Answer 21

Do not remove coronal fragment as cervical fracture has potential to heal. Stabilisation may require longer period of time, up to 4 months

Question 22

when to initiate rct for tooth with root fracture

Answer 22

Monitor healing of fracture for at least one year, monitor pulp status. Do not initiate at emergency visit. Pulp necrosis usually only occurs at coronal segment hence endo coronal segment up to fracture line

Question 23

4 types of root fracture healing outcomes

Answer 23

hard tissue union (best, most favourable outcome)
interposition of connective tissue
interposition of bone and connective tissue
granulation tissue (20-44% chance of pulp necrosis)

Question 24

What is cvek pulpotomy, and how does it compare to vital pulpotomy for primary teeth

Answer 24

Cvek pulpotomy is performed on injured immature permanent teeth with pulp exposure. Open apices. Cvek pulpotomy helps to preserve pulpal function for continued root development

Amputate coronal pulp with high speed with irrigation, vs slow speed round bur or big spoon excavator in pulpotomy for deciduous teeth

Reach vital pulp where there is fresh bleeding. Hemostasis with cotton pellet soaked in saline. Pulp cap. Coronal seal

Question 25

Materials that can be used for pulp cap in cvek pulpotomy

Answer 25

Non setting caoh2
MTA
tricalcium silicate materials eg biodentine

Question 26

what is transient apical breakdown

Answer 26

temporary discolouration and changes to sensibility
usually after moderate injury in mature teeth with closed/closing apex

tooth trying to heal itself, resorbs apical foramen to allow more blood supply to enter pulpal space, resulting in surface resorption and/or obliteration of pulp canal.

grey discolouration and loss of sensibility otherwise no other symptoms. return to normal with normalisation of radiographic condition

Question 27

treatment for intrusion of young permanent tooth with complete root formation

Answer 27

intruded less than 3mm: allow for re eruption without intervention. if does not re erupt in 8 weeks, reposition surgically or orthodontically

intruded 3-7mm reposition surgically or orthodontically

intruded more than 7mm reposition surgically

complete root formation –> pulp almost always becomes necrotic, start RCT asap

Question 28

treatment for intrusion of young permanent tooth with incomplete root formation

Answer 28

allow for eruption without intervention. if no movement within a few weeks, reposition orthodonticallly

intruded more than 7mm, reposition surgically