Obturation of the Cleaned and Shaped Root Canals Flashcards
what is the key objective of RCT
provide an environment that allows healing of periradicular tissues so that the tooth is retained as a functional unit in the dental arch
triad of ……. to complete RCT
preparation, disinfection and obturation
what 6 things must be done/considered when obturating
- apical/lateral seal
- sealer/core materials
- timing of obturation
- length
- assessment
- coronal seal
why is the RC system filled after the nerve is removed
prevent passage of microorganisms and fluid along root canal
blocks apical foramina, dentinal tubules and accessory canals
where should preparation of the RC end
at the junction of pulpal and periradicular tissues
as close to CDJ as possible
1-2mm short of working length
apical constricition
narrowest part of canal
what are some requirements of materials used to fill RC
biocompatible, dimensionally stable, able to seal, unaffected by tissue fluids, insoluble, non-supportive of bacterial growth, radiopaque, removable if retreatment needed
semi solid material as well as root canal sealer to fill voids
what is the most common RC filler material
gutta percha
polymer of isoprene
types of gutta percha obturation techniques
- cold lateral compaction
- warm vertical compaction
- continuous wave compaction
- carrier based obturation
warm vertical compaction
place cone of GP, sever with heat and plug apically
continuous wave obturation
use of electrically heated pluggers and GP, deliver and remove GP
carrier based obturation
stick and handle, warm GP into canal
what is the function of a RC sealer
seal space between dentinal wall and core, fills voids and irregularities in canal, lateral canals and between GP points used in lateral condensation, lubricates during obturation
what are some properties of an ideal sealer
exhibits tackiness to provide good adhesion, establishes hermetic seal, radiopaque, easily mixed, no shrinkage on setting, non-staining, bacteriostatic, slow set, insoluble in tissue fluids, tissue tolerant, soluble on retreatment
zinc oxide eugenol based sealer
effective antimicrobial, cytoprotection, but cytotoxic
glass ionomer sealers
advocated due to dentine bonding properties, minimial antimicrobial activity, greater solubility
removal for retx is difficult
resin sealers
AH plus
good seal, slow setting, good flow, initial toxicity declines after 24hrs
EndoRez = UDMA, good penetration into tubules, biocompactible, good radio-opacity
calcium silicate sealers
high pH 12.8 in first 24hrs of setting
enhanced biocompatibility, no setting shrinkage, non-resorbable, excellent sealing ability, quick set 3-4hrs, ease of use
how to assess quality of obturation
post-op radiograph
length, taper, density, GP and sealer position assesed
assessed in all canals
what to do with the tooth after obturation
adequately restored to prevent bacterial recontamination of RC or fracture of tooth
GI, vitrebond
is coronal or apical seal more important
both must be equally good to ensure best possible outcome
orifice closure
finish obturation at or just below orifice level
GP becomes rapidly infected if exposed directly to oral bacteria
