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46 Cards in this Set
- Front
- Back
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endo explorer?
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DG 16
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3 objectives of access preps
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straight line access
conserve tooth structure complete unroofing of pulp chamber |
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The distobuccal cusp, and therefore canal orifice is located more to the lingual, therefore the distobuccal corner is less prominent
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max 2nd molar
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Access for mandibular 1st molar outline form is usually ? in shape
max 1st? |
trapezoid or rhomboid
rhomboid |
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The distal canal orifice of mand 1st molar is just ? to the ?
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distal to the buccal groove
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entry angle for max molars?
mand? |
mesial to distal
lingual to buccal |
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Chamber roof measurement + 1 tells you how far you need to drill to get to the ?
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pulp chamber
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Possibility of C-shaped anatomy, especially in people of Asian descent
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mand 2nd molars
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don't need to cut unnecessary tooth structure coronal to B and L pulp horns as long as you can get good access for rotary files
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mand molars
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Natural polymer obturating material?
synthetic? |
gutta percha (most common)
Resilon |
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Flexible when heated (thermoplastic), not brittle when cooled down!
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gutta percha
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trans-1,4-polyisoprene (C5H8)n
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gutta percha
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Gutta percha is a polymer of ?
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isoprene
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Natural rubber is ?-polyisoprene
Gutta percha is ?-polyisoprene |
cis
trans |
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" Less symmetrical, less packing"
" Soft, highly flexible, low melting point" |
natural rubber
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" Regular structure, able to crystallize"
" hard, rigid, high melting point" |
gutta percha
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Naturally occurring form of gutta percha?
dental gutta percha? cooled? |
Alpha phase (slow cooled)
Beta phase (fast cooled) |
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Dental gutta percha is mainly ?
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Zinc oxide
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Gutta percha melts at ? so it cannot be ?
disinfect with ? |
100 C
heat sterilized sodium hypochlorite |
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Can't use alcohol or acetone with gutta percha. why?
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it swells
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Dissolves in chloroform, xylene, halothane
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gutta percha
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Gutta percha is ideal except for ? and ?
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adhesion
antibacterial |
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Synthetic polymer: polyester with
bioactive glass & radiopaque fillers |
reslion-Epiphany
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Epiphany primer and sealer create an ? to the tooth
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adhesion
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Resilon-Epiphany system is now called ?
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RealSeal
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" fills spaces between obturating points and canal walls"
" lubricates gutta percha points during compaction" " fills irregularities and lateral canals" |
sealer
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types of sealers
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Zinc oxide eugenol-based"
" Calcium hydroxide-based" " Glass-ionomer" " Resin-based! |
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Important things sealers must do?
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prevent leakage
maintain seal over time |
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thickness of sealer needs to be no more than ? microns
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50
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Zinc Oxide Eugenol-based sealers:
Staybellite resin 27%? Barium Sulfate 15%? Bismuth subcarbonate 15%? soqium borate 1%? |
increase adhesive, decrease solubility
radiopacity control working and setting time (X2) |
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Zinc Oxide setting time:
humidity and body temperature? long and vigorous mixing? smaller ZnO particles? |
decrease (shorter)
decrease increase (longer) |
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High pH --> antimicrobial effect
Dissociate to be effective --> high solubility (not good) |
Calcium hydroxide-based sealers
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Used as medication and not as a long term sealer
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Calcium hydroxide-based sealers
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Hydrophilic & chemical bond to dentin which improves sealing and prevents root fractures
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GI sealers
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" Shorter working time"
" High hardness & low solubility" so its difficult to retreat |
GI sealer
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Epoxy-amine AH Plus (Dentsply)?
base? |
sealer we use
resin-based |
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Epoxy-amine AH 26 produces ? during setting
Epoxy-amine AH Plus doesn't and also is removable with ? |
formaldehyde
solvent |
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"No formaldehyde release
"Paste-paste system – easy to use" "Thermoplastic material (stress absorber)" "Removable with solvent" "High radiopacity" "Moderate antibacterial property" "Slight shrinkage upon setting |
Epoxy-amine AH Plus
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" minimal residual monomer"
" no by-products" " no initiator or catalyst" " long reaction (4 hours)" " still has setting shrinkage |
Epoxy-amine AH Plus
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Better to have good endo and poor coronal restoration or poor endo and good coronal restoration?
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poor endo, good coronal restoration
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? in the root canal creates immediate seal and strengthens tooth
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bonding
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" Coronal dentin vs pulpal vs radicular dentin"
" Unfavorable geometry of the root canal" " Adhesive procedures can be compromised" " Curing mode – light or dual or self-curing?" " Irrigating solution and other chemicals |
limitations to bonding in root canal
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Hybrid layer thickness and resin tag density of dentin ? towards the apical third.
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diminished
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Root canal has a very high ratio of bonded to unbonded surfaces or ?
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C Factor
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? adhesive with ? resin cement is the best choice
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Total-etch
dual-cure |
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Hydrogen peroxide and NaOCl leaves ? layer on the dentin surface
final rinse with ? helps remove |
oxygen-rich
EDTA |
