Trauma 1 and 2 - Class, aetiology, predisposing factors and mechanisms Flashcards
How common is trauma?
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.
What is the cost of trauma?
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.
How common is tooth involvement in oral tissue?
92% involves teeth
28% involves soft tissues
6% involve alveolar and jaw bones
What are the types of traumatic dental injuries?
Injuries to the:
- Hard dental tissues and the pulp
- Periodontal tissues
- Supporting bone
- Gingiva or oral mucosa
What are the types of injuries to the hard dental tissues and the pulp?
a) Crown infraction
b) Uncomplicated crown fracture
c) Complicated crown fracture
d) Uncomplicated crown-root fracture
e) Complicated crown-root fracture
f) Root fracture
What is a crown infraction?
Crack of enamel with no loss of any tooth substance
What is an uncomplicated crown fracture?
No pulp is exposed but:
Can involve both enamel and dentine
What is a complicated crown fracture?
Fracture of enamel and dentine that involves the pulp
What is an uncomplicated crown root fracture?
Fracture that doesn’t involve the pulp but involves the crown and the root
What is a root fracture?
Involves dentine, cementum, and pulp
What are the types of injuries to periodontal tissues?
a) Concussion
b) Subluxation (loosening)
c) Extrusive Luxation
d) Lateral Luxation
e) Intrusive Luxation
f) Avulsion (exarticulation)
What happens during a concussion?
Injury to the tooth-supporting structures that shows:
No abnormal loosening
No displacement of teeth
With marked reaction to percussion
What is subluxation?
Injury to tooth supporting structures:
With abnormal loosening
No displacement
With marked reaction to percussion
Often bleeding from the gingival sulcus
What is extrusive luxation?
Partial displacement of tooth out of its socket in an axial direction
Always associated with fracture in the alveolar socket and comminution
What is intrusive luxation?
Displacement of tooth into alveolar bone.
Always accompanied by comminution and/or fracture of the alveolar socket
What is avulsion?
Complete displacement of the tooth out of its socket
What are the types of injuries to supporting bone?
a) Comminution of alveolar socket
b) Fracture of alveolar socket wall
c) Fracture of the whole alveolar process
d) Fracture of jaw - mandible
- maxilla
What are the causes of comminution of the alveolar socket?
Crushing and compression of the socket always found with intrusion.
Fracture confined to the facial or lingual socket wall resulting in lateral luxation.
What are the types of injuries to the gingiva/oral mucosa?
Laceration
Contusion
Abrasion
What is a laceration?
Shallow or deep wound of the mucosa resulting from a tear and is usually caused by a sharp object
What is a contusion?
A bruise caused by submucosal haemorrhage with no break in the mucosa caused by blunt trauma impact
What is abrasion?
Superficial wound leading to raw, bleeding surface
What causes abrasion?
Rubbing or scraping of the mucosa
How common is dental trauma to primary dentition?
30% if children experience trauma to the primary dentition
How common is dental trauma in children?
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)
What age is most common for dental trauma in children?
2 - 4 and 8 - 10
Which teeth are most commonly injured?
Mainly the upper anterior teeth (11 and 21 most commonly)
What causes dental trauma most often?
Falls
Collisions
Bumps
Bicycles
Sports
Fights
Epileptics
Drug addicts
MVAs
What are the most common types of injuries?
- 9% uncomplicated crown fractures
- 6% complicated crown fractures
- 4% root fractures
- 9% luxations/avulsions
- 6% subsequent trauma
What did the 66 month bunbury study of dental trauma show?
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
What were the most common causes of injuries in the bunbury study?
Permanent dentition (Sports and accidents while playing)
Deciduous dentition (Falls and accidents while playing)
What were the most common dental injuries seen in the bunbury study?
Uncomplicated crown fracture (31.5%)
Subluxation (16.4%)
Lateral luxation (13.2%)
What predisposing factors lead to increased incidence of trauma injuries to teeth?
Increased overjet
Protruding upper incisors
Insufficient lip closure
How can dental injuries result from trauma?
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.
What factors determine the impact and extent of dental injuries?
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)
What are the most common injuries caused by forces in the facial direction?
Concussion
Subluxation
Lateral luxation
