Trauma 1 and 2 - Class, aetiology, predisposing factors and mechanisms

Question 1

How common is trauma?

Answer 1

Several 100s of millions of people are injured every year from trauma.

5000000 people die every year from trauma.

It is the number 1 cause of death in people under 40

Half of all deaths in people between 10 and 24 years of age are caused by trauma.

Question 2

What is the cost of trauma?

Answer 2

Immediate and long term costs approximately 80.2 US million a year

Lost productivity equal to 326 million per year.

4% of the gross domestic product.

Question 3

How common is tooth involvement in oral tissue?

Answer 3

92% involves teeth

28% involves soft tissues

6% involve alveolar and jaw bones

Question 4

What are the types of traumatic dental injuries?

Answer 4

Injuries to the:

1. Hard dental tissues and the pulp
2. Periodontal tissues
3. Supporting bone
4. Gingiva or oral mucosa

Question 5

What are the types of injuries to the hard dental tissues and the pulp?

Answer 5

a) Crown infraction
b) Uncomplicated crown fracture
c) Complicated crown fracture
d) Uncomplicated crown-root fracture
e) Complicated crown-root fracture
f) Root fracture

Question 6

What is a crown infraction?

Answer 6

Crack of enamel with no loss of any tooth substance

Question 7

What is an uncomplicated crown fracture?

Answer 7

No pulp is exposed but:

Can involve both enamel and dentine

Question 8

What is a complicated crown fracture?

Answer 8

Fracture of enamel and dentine that involves the pulp

Question 9

What is an uncomplicated crown root fracture?

Answer 9

Fracture that doesn’t involve the pulp but involves the crown and the root

Question 10

What is a root fracture?

Answer 10

Involves dentine, cementum, and pulp

Question 11

What are the types of injuries to periodontal tissues?

Answer 11

a) Concussion
b) Subluxation (loosening)
c) Extrusive Luxation
d) Lateral Luxation
e) Intrusive Luxation
f) Avulsion (exarticulation)

Question 12

What happens during a concussion?

Answer 12

Injury to the tooth-supporting structures that shows:

No abnormal loosening

No displacement of teeth

With marked reaction to percussion

Question 13

What is subluxation?

Answer 13

Injury to tooth supporting structures:

With abnormal loosening

No displacement

With marked reaction to percussion

Often bleeding from the gingival sulcus

Question 14

What is extrusive luxation?

Answer 14

Partial displacement of tooth out of its socket in an axial direction

Always associated with fracture in the alveolar socket and comminution

Question 15

What is intrusive luxation?

Answer 15

Displacement of tooth into alveolar bone.

Always accompanied by comminution and/or fracture of the alveolar socket

Question 16

What is avulsion?

Answer 16

Complete displacement of the tooth out of its socket

Question 17

What are the types of injuries to supporting bone?

Answer 17

a) Comminution of alveolar socket
b) Fracture of alveolar socket wall
c) Fracture of the whole alveolar process

d) Fracture of jaw - mandible
- maxilla

Question 18

What are the causes of comminution of the alveolar socket?

Answer 18

Crushing and compression of the socket always found with intrusion.

Fracture confined to the facial or lingual socket wall resulting in lateral luxation.

Question 19

What are the types of injuries to the gingiva/oral mucosa?

Answer 19

Laceration

Contusion

Abrasion

Question 20

What is a laceration?

Answer 20

Shallow or deep wound of the mucosa resulting from a tear and is usually caused by a sharp object

Question 21

What is a contusion?

Answer 21

A bruise caused by submucosal haemorrhage with no break in the mucosa caused by blunt trauma impact

Question 22

What is abrasion?

Answer 22

Superficial wound leading to raw, bleeding surface

Question 23

What causes abrasion?

Answer 23

Rubbing or scraping of the mucosa

Question 24

How common is dental trauma to primary dentition?

Answer 24

30% if children experience trauma to the primary dentition

Question 25

How common is dental trauma in children?

Answer 25

30% primary dentition

22% permanent dentition by the age of 14

Every second child had a dental injury by 14 (boys almost twice as often as girls)

Question 26

What age is most common for dental trauma in children?

Answer 26

2 - 4 and 8 - 10

Question 27

Which teeth are most commonly injured?

Answer 27

Mainly the upper anterior teeth (11 and 21 most commonly)

Question 28

What causes dental trauma most often?

Answer 28

Falls

Collisions

Bumps

Bicycles

Sports

Fights

Epileptics

Drug addicts

MVAs

Question 29

What are the most common types of injuries?

Answer 29

73. 9% uncomplicated crown fractures
74. 6% complicated crown fractures
75. 4% root fractures
76. 9% luxations/avulsions
77. 6% subsequent trauma

Question 30

What did the 66 month bunbury study of dental trauma show?

Answer 30

68% of patients were male (mean age 14.1) and 32% female (mean age 11.6)

92% of patients were less than 34 years old but patients were between 10 months and 78 years old

70% were permanent teeth and 30% primary teeth

Average of 1.7 teeth per patient

Maxillary central (44%) and lateral incisors (13%) were most commonly damaged teeth followed by the mandibular teeth.

No significant difference was seen in the timing of accidents

Question 31

What were the most common causes of injuries in the bunbury study?

Answer 31

Permanent dentition (Sports and accidents while playing)

Deciduous dentition (Falls and accidents while playing)

Question 32

What were the most common dental injuries seen in the bunbury study?

Answer 32

Uncomplicated crown fracture (31.5%)

Subluxation (16.4%)

Lateral luxation (13.2%)

Question 33

What predisposing factors lead to increased incidence of trauma injuries to teeth?

Answer 33

Increased overjet

Protruding upper incisors

Insufficient lip closure

Question 34

How can dental injuries result from trauma?

Answer 34

Trauma can be direct or indirect

Direct involves direct force to the tooth.

Indirect often involves forced closure of the lower jaw against the upper jaw.

Question 35

What factors determine the impact and extent of dental injuries?

Answer 35

Energy of impact (includes both mass and velocity)

Resiliency of impacting object (cushioned objects distribute the impact more)

Shape of impacting object (sharp objects cause clean crown fractures with minimum displacement of the tooth and blunt force causes luxation or root fracture)

Direction of impacting force (most often facially and perpendicular to the long axis of the tooth)

Question 36

What are the most common injuries caused by forces in the facial direction?

Answer 36

Concussion

Subluxation

Lateral luxation