Endodontics
Course Review
Enoch Ng, DDS 2014
Root Resorption
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Condition associated with physiologic or pathologic process resulting in loss of dentin, cementum, and/or bone
o
Similar to process of bone resorption
o
Involves dentinoclasts and cementoclasts
Resorption Mechanism
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Clastic cells bind to extracellular proteins containing arginine-glycine-aspartic acid sequence (RGD) of aminoacids
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RGD peptides bound to calcium salt crystals on mineralized surfaces serve as clastic cell binding sites
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Activated clastic cells produce acidic pH (3.0-4.5) – increases hydroxyapatite solubility
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Covering of cementum and predentin over dentin essential to resistance of dental root resorption
o
Clastic cells cannot bind to unmineralized matrix
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Bacteria and inflammation are part of the process
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Differential diagnosis – important for treatment planning – NSRCT vs surgical repair
Internal Root Resorption
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Pathologic process initiated within pulp space with loss of dentin and possible invasion of cementum
o
Clastic cells come from dental pulp
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Outermost odontoblastic layer and predentin layer of canal wall damaged, exposes mineralized dentin layer to
clastic cells
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Pulpal tissue apical to resorptive lesion must have viable blood supply to sustain clastic cells
Internal inflammatory resorption
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Often associated with history of trauma
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Requires vital pulp for progression
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Low grade chronic pulpal inflammation
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Asymptomatic unless perforation occurs
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Can be transient or progressive
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Displays as pink tooth mummery
Radiographic features
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Fairly uniform, clearly defined radiolucent
enlargement of canal
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Canal cannot be seen through resorptive defect
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Defect stays centered on angled radiograph
Internal replacement resorption
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From low-grade irritation to pulpal tissue, like
chronic irreversible pulpitis or partial necrosis
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Pulpal tissue replaced with bone or cementum like
hard tissue
Treatment – Immediate NSRCT
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Process halted by pulpal extirpation
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Ultrasonic cleaning with NaOCl
o
For perforations, use normal saline or
chlorhexidine (not NaOCl)
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Hemorrhage control essential, can be difficult
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Ca(OH)
2
treatment interappointment
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Obturation with warm gutta percha technique
Treatment
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Ultrasonic cleaning with NaOCl
o
For perforations, use normal saline or
chlorhexidine (not NaOCl)
-
Ca(OH)
2
treatment interappointment
-
Obturation with warm gutta percha technique