1 - Resorption Flashcards
Define root resorption.
Non-bacterial destruction of dental hard and soft tissue due to the interaction of clastic cells
What cells initiate root resorption?
- osteoclast by definition, although referred to as dentinoclast when on dentine
- originate from multinucleated giant cells
What are the features of dentinoclasts?
- motile (can move from bone to dentine root surface when PDL is not present)
- ruffled border that releases proteolytic enzymes
What stimulates dentinoclasts?
RANKL
What up-regulates RANKL?
Unknown although below answers are thought possible
- parathyroid hormone
- bacterial lipopolysaccharides
- trauma
- chronic inflammation
Give an examples of a RANKL inhibitor.
Denosumab
What trauma are most likely to result in root resorption?
- avulsion
- lateral luxation
- intrusion
What surfaces protect against root resorption?
- PDL
- cementum (non mineralised layer)
- predentine (non-collagenous component)
How is root resorption classified?
- internal
- external
What are the types of internal root resorption?
- inflammatory
- replacement
What are the types of external root resorption?
- inflammatory
- replacement
- cervical
- surface
How do you differentiate between external and internal resorption on a radiograph?
- external, tramlines are still visible, parallax applies
- internal, bulbous deformity in tramlines, parallax does not apply
Describe the clinical findings in internal inflammatory resorption.
- no pocketing unless root surface perforated
- no sinus unless periradicular disease
- no TTP
- no mobility
- positive response to sensibility
Describe the radiographic findings in internal inflammatory resorption.
- centred in canal, tramlines move with bulbosity
- does not move with beam shift
- usually no PA radiolucency
Describe the pathogenesis of internal inflammatory resorption.
- coronal pulp is necrotic, apical pulp is vital
- lesion includes inflammatory and vascular tissue and will communicate with PDL if perforation present
- lesion progresses until apical pulp becomes necrotic and blood supply is lost