endo materials

Question 1

compare the file materials

Answer 1

Stainless steel – files have a twisted wire and have different cross sections

Nickel-titanium (NiTi) – have shape memory and super elasticity

Comparing – NiTi has lower modulus, better fatigue life, is more expensive

Question 2

what is an irrigant

Answer 2

removes debris and provides lube

Question 3

types of irrigants

Answer 3

sodium hypochlorite
- 0.5 -5.25%
- needs to be changed freq
- dissolves proteolytic debris
- antibacterial
- can affect instruments
- possible toxicity

chlorohexidine
- up to 2% soln
- adheres to dentine
- not proteolytic
- antibacterial

EDTA and other chelating agents
- 10 -18%
- as soln or paste
- also acts as lubricant
- dissolves smear layer
- best used in conjuction with sodium hypochlorite

Question 4

materials for obturation

Answer 4

Gutta percha -> biocompatible, insoluble, thermoplastic

Resilon -> similar handling to GP, softened by heat, dissolved by solvents, needs self-etch primer for good bond

Question 5

medicaments use in endo

Answer 5

MEDICAMENTS – should be anti-inflammatory, anti-bacterial, and stimulate hard tissue repair

Calcium hydroxide
Ledermix paste
Phenolic compounds

Question 6

list canal sealers and its ideal properties

Answer 6

Ideal properties -> slow set, good flow, insoluble, no shrinkage, radiopaque, bacteriostatic, easy to remove, no shrinkage

• Zinc oxide eugenol (some solubility)
• Calcium hydroxide (bactericidal, high solubility)
• Resin based sealer (has some shrinkage)