Biological Response to Traumatic Dental Injuries

Question 1

What type of trauma is this?

Answer 1

Enamel infraction

Question 2

What type of trauma is this?

Answer 2

Enamel fracture

Question 3

What type of trauma is this?

Answer 3

Enamel-dentin fracture

Question 4

What type of trauma is this?

Answer 4

Enamel-dentin-pulp fracture

Question 5

What type of trauma is this?

Answer 5

Root fracture

Question 6

What type of trauma is this?

Answer 6

Alveolar fracture

Question 7

What type of trauma is this?

Answer 7

Crown root fracture without pulp involvement

Question 8

What type of trauma is this?

Answer 8

Crown root fracture with pulp involvement

Question 9

In terms of periodontal trauma define concussion

Answer 9

Injury without abnormal loosening or displacement there is a reaction to percussion

Question 10

In terms of periodontal trauma define subluxation

Answer 10

Injury with abnormal loosening
No displacement of tooth

Question 11

In terms of periodontal trauma define extrusive luxation

Answer 11

Partial displacement of tooth

Question 12

In terms of periodontal trauma define intrusive luxation

Answer 12

Displacement into alveolar bone

Question 13

In terms of periodontal trauma define lateral luxation

Answer 13

Displacement (not axial)
Associated with alveolar bone fracture

Question 14

In terms of periodontal trauma define avulsion

Answer 14

Complete displacement of tooth

Question 15

What are the contents of the dental pulp?

Answer 15

Fibroblasts
Odontoblasts (line outer layer)
Progenitor/Stem cells
Inflammatory cells
Vascular & Nerve cells
Loose connective tissue
Giant cells

Question 16

Name the inflammatory cells present in the dental pulp

Answer 16

Polymorphs
T Lymphocytes
Macrophages
Dendritic antigen-presenting cells

Question 17

What things can be obsereved visually to suggest dental trauma?

Answer 17

Soft tissue lacerations
Swelling or bruising (indicative of inflammation)
Abscess formation
Mobility/displacement of tooth
Crown fractures
Tooth discoloration

Question 18

How can sound help diagnose dental trauma?

Answer 18

Percussion test can be carried out and if dull or high-pitched metallic sounds compared to neighbouring teeth then trauma may be suggested

Question 19

On percussion a tooth makes a high-pitched metallic sound what dental trauma could this suggest?

Question 20

On percussion a tooth makes a high-pitched metallic sound what dental trauma could this suggest?

Answer 20

Intrusion or lateral luxation

Question 21

How do pulp sensibility and pulp vitality tests differ?

What type of tests are Endo-frost and EPT?

Answer 21

Pulp sensibility assessing pulpal nerve supply
Pulp vitality which assesses blood flow

Sensibility

Question 22

Comment on sensibility during root development

Answer 22

Level of pulp sensibility DECREASES with INCREASED root development

UNTIL full root development (closed apex) where sensibility increases to highest

Question 23

What are the different reactions the pulp can have post trauma?

Answer 23

Pulp survival
Pulp canal obliteration
Pulp necrosis
Inflammatory internal resorption
Replacement internal resorption

Question 24

Describe what occurs biologically for pulp survival post dental trauma

Answer 24

1. Mild trauma occurs
2. Tertiary/Reactionary dentine laid down by odontoblasts

Question 25

Describe what occurs biologically for pulp canal obliteration post dental trauma

Answer 25

1. Extensive trauma occurs 2. Odontoblasts die 3. These are replaced by progenitor cells which secrete Reparative dentine

Question 26

Clinically what may you see in a tooth that has undergone pulp canal obliteration?

Answer 26

Discolouration of tooth (Yellow)

Question 27

What do you see in this radiograph?

Answer 27

Pulp canal oblitertation Reduction in/loss of visible pulp

Question 28

What clinically can be obsereved in a patient which has pulp necrosis following trauma?

Answer 28

Discolouration of tooth (Grey/Black as haemoglobin broken down into hemosiderin)

Question 29

What radiographically can be obsereved in a patient which has pulp necrosis following trauma?

Answer 29

Periapical radiolucency (Abscess/Cyst formation)

Question 30

Biologically what occurs to a tooth during an Inflammatory Internal Resorption post dental trauma?

Answer 30

Inflammation occur which which leads to infiltration of polymorphs and giant cells Which then leads to resorption of the pulp and dentine

Question 31

What radiographically can be obsereved in a patient which has inflammatory internal resorption following trauma?

Answer 31

Radiolucent expansion seen in the pulp canal

Question 32

What are the two types of inflammatory internal resorption?

Answer 32

Transient (reversible) Permanent (non-reversible/progressive)

Question 33

Biologically what occurs to a tooth during replacement internal resorption post dental trauma?

Answer 33

Stem cells in pulp differentiate into osteoblasts & areas are replaced with bone tissue

Question 34

Define ankylosis

Answer 34

Fusion between the tooth surface (cementum) & alveolar bone

Question 35

What are the diffrent types of periodontal reactions following dental trauma?

Answer 35

Normal healing External resoption * Surface ER * Inflammatory ER * Replacement ER

Question 36

What are the diffrent types of gingival reactions following dental trauma?

Answer 36

Normal Healing Loss of attached gingivae

Question 37

What are the diffrent types of root development reactions following dental trauma?

Answer 37

Continuous Disrupted Arrested

Question 38

What are the different factors influencing pulp survival post-trauma?

Answer 38

1. Severity of damage to blood supply 2. Area exposed (size of pulp exposure/trauma) 3. Length of exposure 4. Stage of root development

Question 39

Which types of dental trauma are the most and least destructive to the tooths blood supply? Comment on the role of elastin in blood vessels in preventing damage?

Answer 39

Least with concussion & most with avulsion & intrusive luxation Subluxation & Extrusion have less blood vessel damage due to elastin in blood vessels, allows for some leeway as tooth moves away (vs. being pushed in)

Question 39

Which types of dental trauma are the most and least destructive to the tooths blood supply? Comment on the role of elastin in blood vessels in preventing damage?

Answer 39

Least with concussion & most with avulsion & intrusive luxation Subluxation & Extrusion have less blood vessel damage due to elastin in blood vessels, allows for some leeway as tooth moves away (vs. being pushed in)

Question 40

Comment on the relationship between apical pulp width and replantation

Answer 40

Larger the apical pulp width = Higher chance of pulpal revascularisation after replantation

Question 41

How should teeth needing to be replanted be kept?

Answer 41

The longer a tooth is in dry storage before being replanted = Less chance of pulpal revascularisation Therefore, wet storage (saliva/saline/milk)

Question 42

Outline a Cvek partial pulpotomy

Answer 42

1. Administer LA & isolate w/rubber dam 2. Remove 1-2mm of exposed pulp with high-speed diamond bur w/water 3. Control haemorrhage w/saline (or chlorhexidine) soaked cotton pellet 4. Cover pulp w/layer of non-setting CaOH then seal w/layer of Setting CaOH 5. Restore the tooth w/ Composite 6. Revaluate tooth in 6-8 weeks and then 1 year to monitor tooth vitality & root development

Question 43

A 10 year old patient presents with a fracture in his upper permanent central incisor (enamel and dentine with minor pulp exposure) How would you treat this immediately?

Answer 43

Clinical decision is dependant on maturity of tooth. If the tooth is immature (apex not fully formed): carry out pulp cap or partial pulpotomy. Use Ca(OH)2 If the tooth is mature: carry out RCT or pulp cap/pulpotomy Then restore the tooth with restorative materials or with the bonded tooth fragment