Root Canal Irrigation Flashcards
Microbiology of primary root canal infection?
Polymicrobial
Obliagte anaerobic bacteria
Use of irrigants?
Kill and remove microorganis
Remove microorganism
Remove dentine debris and smear layer
Lubrication for insturcments
Why need irrigations?
Only 60% canal wall instrumented
Irregular and complex system - lateral
What is smear layer?
Created during cleaning and shaping
Inorganic and organic substance, microorganism and nectrotic debris
Issue w/ smear layer?
Protect bacteria
Inhibit penetration irrigant into tubules
What needle use for irrigations?
Side venting needle
What is biofilm?
Adherent cells/ microorganism in matrix of extracellular polymeric substance
What is a resistant microbe found in root canals?
E. Faecalis - resistant NaOCl
Associated w/ failure of RCT
Ideal characteristic irrigant?
Effective antimicrobial Non irritating PA tissue Active presence blood, serum Not stain tooth Doesn't induce immune response Able remove smear layer Non toxic No adverse effect physical properties dentine Easy use Inepxensive No adverse effect sealing ability materials
Ideal way to prepare/clean canals?
Mechanical and chemical prep
Mechanical prep allows penetration irrigant to apical region
Examples of irrigants currently used?
Sodium hypochlorite NaOCl
EDTA
CHX
Advantage NaOCl?
Only one dissolves organic matter - biofilm
Antimicrobial
Cheap
Issue NaOCL?
Dillute - larger volumes irrigant required
Disadv NaOCL?
Doesn’t remove dentine debris/smear layer
Affect dentine properties
Rare case allergy
Toxic vital tissue
Potential problems of using NaOCl?
Extrusion injuries
Damage to insturments
What can EDTA be used for?
Removal of smear layer
Used for penultimate rinse
What two irrigants should never be used together?
CHX and NaOCl
Forms brown precipitate - potentially carcinogenic
Need use saline in between
Issue using iodine potassium iodide?
Allergic reaction iodine
Stain dentine
No tissue disolving
Unable remove smear layer
How does hydrogen peroxide work?
Free radicals which destroy proteins and DNA
Issue w/ hydrogen peroxide?
Can release 02 bubbles - can lead air emphysema
What is MTAD?
Mixed tetracycline, acid and detergent
Issue MTAD?
Expensive
Risk bacterial resistance
Tetracycline staining
Current protocol for irrigating?
Use NaOCl throughout followed penultimate flush EDTA
NaOCl - removes organic
EDTA - removes smear layer
What instrument can increase efficacy of irrigants?
Ultrasonic
