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
How do you manage internal inflammatory resorption?
- orthograde endodontics only
- CaOH used as intervisit medicament due to caustic properties that chemically disinfect areas that are unable to be instrumented due to morphology of resorption
Describe the radiographic findings in internal replacement resorption.
- incidental finding
- pulp is replaced by bone/PDL/cementum and appears radiopaque with trabecular pattern
Describe the clinical findings in internal replacement resorption.
No abnormal clinical findings
How do you manage internal replacement resorption?
- no treatment until symptomatic
- if symptomatic or fractures, requires tooth replacement option
- RCT very unpredictable
Describe the clinical findings in external surface resorption.
- increased physiological mobility
- positive response to sensibility
Describe the radiographic findings in external surface resorption.
- roots appear short
- PDL intact
- pulp normal
- root can appear with trabecular pattern after healing of previous surface resorption
How do you manage external surface resorption?
- remove source of resorption
- endodontics ineffective
- splint teeth if mobile
- DWP risk associated with perio, as less supporting root structure and tooth loss more likely
Describe the pathogenesis of external surface resorption.
- orthodontics, as teeth move through bone the root is resorbed away, teeth used for anchorage are worst affected
- ectopic teeth
- cysts
- idiopathic
What is the percentage of teeth experience external surface resorption?
- 90% experience
- 2-5% have severe
