what are some reasons we use sealer?
- it acts as a lubricant for placement of gutta percha
- creates a water-tight seal to prevent re-entry of bacteria into the canal
- when gutta percha is cooled, it shrinks, so sealer helps fill the spaces left by cooled GP
what are the ideal properties of a sealer?
- tissue tolerance
- no shrinkage with setting
- slow setting time
- adhesiveness
- radiopacity
- absence of staining
- solubility in solvent
- insolubility or oral and soft tissue fluids
- bacteriostatic
- ability to create a seal
what are 3 ways we can determine whether or not we have reached the apex?
- tactile sensation
- electronic apex locator
- x-ray
the closer you are to the apex, file movement should be ___
passive
which obturation technique has been used the longest, is the most commonly used, and is considered the gold standard?
lateral condensation
what is the master apical cone?
- the gutta percha cone that is same size as the master apical file (i.e. it reaches working length)
- it is the first gutta percha cone that is placed during obturation
- it should fit snugly so there is resistance
what are red spreaders used for? what gutta percha cones correspond to red spreaders?
- MAF under #40
- fine-fine GP
what are blue spreaders used for? what gutta percha cones correspond to blue spreaders?
- MAF over #40
- med-fine GP
what section of the canal should you fill your gutta percha
within 2-4mm of the coronal portion
what bur should you use for initial access?
330
how deep should the initial prep be?
1.5mm, which is the length of the cutting flutes of the #330 bur
what is the number 1 obturation material used in endodontics?
gutta percha
how long has gutta percha been used?
- over 100 years (according to siri)
- or over 160 years (according to the textbook)
chemically, gutta percha is the trans form of ___
poly isoprene
what are the 3 forms that gutta percha comes in?
- alpha (cold type)
- beta (room temp, most common used)
- gamma (hot type)
what are 5 advantages of gutta percha?
- bio inert
- nonirritating to periapical tissues
- easily inserted and removed
- dimensionally stable
- does not discolor the tooth
gutta percha can not be sterilized. it can only be disinfected with what 3 liquids?
- alcohol
- chlorhexidine
- sodium hypochlorite
T or F:
gutta percha does not need to be used with sealer in order to effectively seal a canal
- false
- it needs sealer to really seal the canal effectively
what are 10 qualities of an ideal obturation material?
- be easily introduced into the canal
- seal the canal laterally and apically
- not shrink after insertion.
- be impervious to moisture
- be bactericidal or at least discourage bacterial growth
- be radiopaque
- not stain the tooth structure
- not irritate periapical tissues or affect the tooth structure
- be sterile or easily sterilized
- be easily removed from the root canal
obturating materials can be solid or semisolid. which type requires sealer?
solid
what is a major advantage of solid obturation material over semisolid material?
the clinician’s ability to better control length and also a reasonable ability of the solid material to adapt itself to irregularities and create an adequate seal throughout the root canal system
the primary bulk ingredient of a GP cone is ___, 20% is ___, and the remaining ingredients are ___, ___, and ___
- zinc oxide (~75%)
- gutta percha
- binders, opaquers, and coloring agents
what are the two basic shapes of gutta percha cones? which shape conforms to either the International Organization of Standardization (ISO) or the American Dental Association/American National Standards Institute (ADA/ANSI)?
- standard and nonstandard (conventional)
- standard (i.e. standardized cones are designed to have the same size and taper as the corresponding endodontic instruments used to prepare the RCS)
what are the 4 major advantages of gutta percha?
- it adapts with compaction to irregularities in prepared canals
- it is easy to manage and manipulate
- it is relatively easy to remove from the root canal
- it is relatively biocompatible, being nearly inert over time when in contact with connective tissue
