10. Trauma in permanent teeth Flashcards
When does root formation normally occur?
Root formation is normally complete 3 years after eruption
How can you get damage to the PDL?
- if the tooth is pushed into the root surface, there is crushing of the PDL and so the neurovascular bundle is crushed and you may see bleeding at the root surface
- if the tooth is extruded, you will get stretching of the PDL
What can damage to the PDL cause?
- ## may lead to external resorption of the root
Why does resorption occur and what is the outcome of it dependent on?
- damage to precementum or PDL
- osteoclastic damage to root surface
- outcome depends on size resorptive defect and presence/absence of inflammation
What are the 3 types of external root resorption?
- repair related resorption- often seen in ortho tx, PDL membrane space is trying to be redistributed, self-limiting
- ankylosis related replacement root resorption
- infection related resorption- pulp necrosis and inflammatory response
What does ankylosis related replacement root resoprtion appear like on radiograph?
- often get complete obliteration of the PDL space in places
- radiopacities indicative of bone on the root surface
What does repair related root resorption look like on radiograph?
- some root surface radiolucency but it is not continuing
- redistribution of the PDL membrane space
What is transient apical breakdown in bone?
Transient apical breakdown has been reported to occur in cases in which a periapical radiolucency develops and resolves without treatment following luxation injury.
- there is no permanent damage to the pulp
- if you repeated x ray you will see redistribution of PDL space
What special investigations do you need to do?
- appropriate radiographs
- sensibility testing (neural activity)- baseline and subsequent
- vitality (pulpal response)- pulse oximeter, doppler/laser flowmetry
What is the effect of trauma on the pulp?
- get disruption of blood supply
- pulp tissue becomes infarct
- coagulation necrosis occurs
- if there is bacteria you get infection related necrosis. Diminished in tooth with closed apex.
- if there is no bacteria you get revascularisation or regeneration/repair. There is opportunity to revascularise in a tooth with open apex.
What is the treatment for concussion?
- take radiograph and sensibility test
- monitor 4 weeks and 1 year clinical and radiographic
What is the definition of subluxation?
- injury to the tooth supporting structures with abnormal loosening but without displacement of the tooth
What are the clinical findings seen in subluxation?
- tender
- increased mobility
- bleeding from gingival crevice
- may not respond to sensiblility tests
What is the treatment for subluxation?
- normally monitor
- if increased mobility splint for 2 weeks
What time periods do you monitor subluxation?
- 12 weeks, 6 months and 1 year
- take 2 radiographic views
When should you do root canal for subluxation cases?
- a false negative response may be present for several months- do not extirpate solely on no response
- if signs of pulp necrosis/infection/AAP or inflammatory resorption commence root canal treatment
- open apex is more likely to revascularise
What is the definition of extrusive luxation?
- displacement of the tooth out of its socket in an incisal/axial direction
What are the clinical findings of extrusive luxation?
- tooth appears elongated
- increased mobility
- likely to have no response to sensibility tests
What radiographs do you take for extrusive luxation?
- 2 views
- often see increased PDL space
- need to take 2 views before you replace the tooth as you need to make sure there is no root fracture
What is the treatment for extrusive luxation?
- reposition under LA
- splint 2 weeks (may require 4 weeks if fracture of marginal bone)
- if pulp becomes necrotic and infected, start endo treatment
How often do you do clinical and radiographic reviews for extrusive luxation?
4 weeks, 8 weeks, 12 weeks, 6 months, 1 year and then yearly for 5 years
What can happen to the pulp in extrusive luxation?
- pulp canal obliteration can occur
- this is normal signs of a vital tooth
- however, in small percentage of cases the tooth may become necrotic and non-vital so may see apical radiolucency so RCT needs to be commenced
- pulp survival and pulp obliteration is higher in open apex
What is lateral luxation?
- displacement of the tooth in any lateral direction (labially or palatally), usually associated with compression of the alveolar socket wall/cortical bone
What are clinical features of lateral luxation?
- displaced palatally or labially
- usually associated with fracture of bone
- immobile as the apex of the root is locked in
- percussion will give it a high metallic sound
- likely to have no response to endofrost due to damage to the neurovascular pulp tissue