23)Drugs for pulp devitalisation, Fluoride + Root canal filling materials

Question 1

Pulp Devitalisation

Answer 1

Destroying the vitality of a tooth/ pulp of a tooth

Question 2

Gluteraldehyde

Answer 2

A drug that ensures that less necrosis of pulpal tissue occurs

• It is a good antimicrobial
• Has limited diffusivity
• Has superior fixation by cross linkage (bridge)

Question 3

Ferric sulphate

Answer 3

Also used for pulp devitalisation

• Haemostatic compound
• Forms ferric ion protein complex ⇢ occludes capillaries
• Root resorption is not accelerated

Question 4

Fluorides

Answer 4

Prevent tooth decay

• Present in drinking water, mouthwashes + toothpaste
• Fl^- ions convert to hydrofluoric acid in gut
• 50% of fluoride excreted in urine
• ½ life = 1-5 hours

Side effects

• Overdose = fluorosis + fluoride poisoning
• Lethal dose = 5-10g
• GI discomfort

Question 5

Root canal filling materials

Answer 5

• Prevent bacteria from/through canal system to periapical area
• Material should prevent infection
• Must be biocompatible ⇢ will provide basis for promoting healing of periodontal tissues

Question 6

ZnO Eugenol

Answer 6

• Successful use over extended period
• Resorbed if extruded into peri-radicular tissues

Question 7

Calcium Hydroxide

Answer 7

• Recently introduced for therapeutic effects
• NOT recommended

Question 8

Glass ionomer

Answer 8

Pros

• Dentin-bonding properties
• Beneficial to surrounding tissues ⇢ becomes a resovoir of fluoride

Cons

• Difficult to remove if re-treatment is required

Question 9

GUTTA-PERCHA

Answer 9

• Non soluble
• Non irritant
• Fills empty space inside root after endodontic therapy
• Must be used w/sealer to help adhere to canal walls

Pros

• Inertness
• Biocompatibility
• Melting point
• Ductility