Root resorption Flashcards
Definition of root resoption
- Non bacterial destruction of dental hard and soft tissue due to interaction of osteoclastic cells
What are osteoclasts , why do they contribute to root resoprtion?
- Large multinucleated cells found within Howships lacunae on hard tissue
- Highly motile
- have ruffled border in contact with dentine
- Integrins hold the ruffled border to dentine
- Intracellular vesicles release proteolytic enzymes and hydrogen ions = acidic environment
= dissolution calcified hard tissue
Give reasons for why RANKL stimulation causes osteoclasts to become activated?
- Parathyroid hormone, B3, IL-1B
- Bacterial lipopolysaccharides
- Trauma (physical or chemical)
- Chronic inflammation
What surfaces on the root act to prevent resorption?
- Periodontal ligament
- Cementum (in partic non mineralised layer)
- Predentine ( non collagenous component)
all prevent osteoclasts adhering or reabsorbing unmineralized matrix
Give the types of Internal and External root resoprtion
Internal
- Inflammatory
- Replacement
External
- Inflammatory
- replacement
- Cervical
- Surface
What radiographic examination can be helped for root resorption diagnosis?
- 2 angles (ideally 30degress mesial or distal beam shift)
- CBCT
What are the clinical of internal inflammatory root resorption?
- The coronal integrity can be unrestored
- Colour normal
- Mobility normal
- +ve response to sensibility testing
- Usually no sinus, swelling, apical tenderness
- No perio pocketing unless lesion has perforated root surface
What type of root resorption is this? Give the radiographic findings
- Internal inflammatory
- The widening of pulp canal is centred in the canal and doesn’t move with beam shift
Give the pathogenesis of internal inflammatory root resroption
- Coronal pulp necrotic
- Lesion includes inflammatory and vascular tissue (if perforated then communicates with PDL)
- Apical pulp vital
- Lesion will progress until apical pulp is completely necrotic
Txt of internal inflammatory RR
Orthograde endo only
- May has poss haemorrhage
- Active irrigation sodium hypo
- Intervist medicament of Ledermix (anti inflam properties)
- Thermal obturation
Give the radiographic and clinical findings of internal replacement resorption
- Asymm and irregular enlagrment of pulp canal with distortion of canal anatomy
- Canal/pulp may appear obliterated or replaced with mixed radio-opaque area with loss of root canal walls
- May appear as pink area on crown of tooth
- +ve vitality test unless crown or root perforation
Txt of Internal replacement RR
- Identify cause and holt osteoclastic actvity
- orthograde endo
- Stop ortho
- XLA
What is the aetiology of external surface resoprtion?
Mainly ortho
- 90% 1mm expected 2yrs
- 1-5% severe (more than a 1/3 orig root)
- 15% mod
- Usually teeth used for anchorage worst affected
- Ectopic teeth (pressure form erupting tooth)
- Pathological lesions (P from adjacent pathological lesion)
- idiopathic
What is this type of resorption?
- External surface resorption
- PDL remains intact
TXT of external surface resorption
- Pulp is healthy therefore endo will have no effect
- Remove source to stop resoprtion (stop endo) and splint if mobile teeth
What is the main difference between external inflammatory and external surface resorption?
- External inflamm will have -ve response to sensitivity as the pulp is necrotic
What type of RR is this? Pulp is negative to sensibility testing
- External inflammatory
What is the aetiology of external inflammatory resorption? What is the txt?
- Pulp is necrotic so bacterial or dental trauma origin
- PA inflam lesion precipitates the resorption process
TXT
- Remove cause of inflammation
- endo txt or XLA
What are the clinical and radio findings of external replacement resorption?
- May be infra occluded
- May be erythematous gingivae
- No tenderness but high pitched note
- No mobility
- Positive to sensitivty
TXT options for external replacement resorption
- Accept pos and restore incisal level with comp and monitor
- Autotransplantation of premolar
- Surgical respositioning
- Extraction (time this with pubertal growth if in children) and ortho space closure
- Decoronation (if >1mm infraoccluded) to preseve bone vol and implant later on
Aetiology of external replacement resorption?
Trauma
- Avulsion or lateral luxation
- Sig injuries to periodontium so osteoclasts in contact with external root dentine to begin RR
Clinical and radiographic findings of external cervical resorption
- Extensive perio pocketing and profuse BOP into soft granulation at CEJ
- Pink spot colour
- Normal or no mob
- +ve sensitivty
Describe this classification of external cervical resorption
Classified into apico-coronal direction and circumferential
Apico-coronal direction
1. Crestal
2. Coronal 1/3
3. Middle 1/3
4. Apical 1/3
Circumferential
1. 1/4
2. 1/2
3. 3/4
4. More than 3/4
What are the risks ass with external cervical resorption?
- Ortho
- Trauma (avulsion and luxation)
- Wind instruments
- Internal bleaching
- viral infections
- Systemic disturbance like thyroid issues
Max canine > max incisor > mand molar
TXT options external cervical resoprtion
- Monitor (likely will continue)
- XLA and prosthetic replacement
- Internal repair (MTA) and orthograde endo
How are osteoclasts stimulated ?
- RANKL stimulation
- RANKL liverated from osteoclasts and stromal cells found on surface of monocytes and macrophages
- Stimulation leads to fusion of mononuclear cells and macrophages to become osteoclasts
- OPG inhbits RANKL so inhibts osteoclastic activity
- Careful balance of OPG and RANKL needed for bone remodelling in ortho
How does MTA work?
- Mineral trioxide aggregate
- release calcium ions for cell proliferation
- Creates antibacterial envrion with alkaline pH regulating cytokine production
- useful for perforation of root
