DMS Flashcards
COMPONENTS OF COMPOSITE RESIN
glass filler particles resin camphorquinone low weight dimethacrylates silane coupling agents
WHAT ARE GLASS FILLER PARTICLE EXAMPLES IN COMPOSITE
microfine silica
quartz
hard things
WHAT IS THE RESIN PART OF COMPOSITE RESIN
bisGMA
soft
WHAT IS THE LOW WEIGHT DIMETHACRYLATE IN COMPOSITE AND WHAT DOES IT DO
triethylene glycol dimethacrylate (TEGDMA)
adjusts viscosity / reactivity
WHAT DOES THE SILANE COUPLING AGENT IN COMPOSITE DO
allows for intimate bonding between filler and resin
WHAT IS THE SETTING REACTION OF COMPOSITE WE USE
light cure - 1 paste, blue light 440nm activates camphorquinone
= free radicals by breaking C=C bonds
= polymerisation reaction
WHAT ARE THE TYPES OF COMPOSITE
conventional
hybrid
microfine
USE OF COMPOSITE
direct filling material
COMPONENTS OF GIC GLASS POWDER (BASE)
silica
alumina
various salts : calcium fluoride / aluminium fluoride / aluminium phosphate
COMPONENTS OF GIC LIQUID (ACID)
polyacrylic acid
tartaric acid
itaconic acid
WHAT DOES THE RATIO OF ALUMINA TO SILICA IN GIC POWER ALTER
translucency
WHAT DOES TARTARIC ACID CONTROL
setting characteristics
WHAT DOES ITACONIC ACID CONTROL IN GIC
viscosity
WHAT ARE THE STAGES OF SETTING REACTION FOR GIC
dissolution
gelation
hardening
WHAT HAPPENS IN DISSOLUTION OF GIC
glass dissolves in acid as H+ attacks
silica gel formed around unreacted glass
WHAT HAPPENS IN THE GLATIUON STAGE OF GIC SETTING
this is setting in the mouth
the calcium crosslinks polyacrylic acid chains by chelating with its H+ ions
protect from moisture
takes minutes
WHAT HAPPENS IN THE HARDENING STAGE OF GIC SETTING
trivalent aluminium ions crosslink more polyacrylic acid chains = hard
USES OF GIC
restorative material core build up before crown lining under fillings luting - Fuji fissure sealants endo cavity temp rest ortho cement
WHICH MATERIALS ARE LIGHT CURE
composite and RMGI
COMPONENTS OF RMGI POWDER
fluro-alumino silicate glass barium glass vacuum dried polyacrylic acid potassium persulphate ascorbic acid pigments
COMPONENTS OF RMGI LIQUID
HEMA polyacrylic acid with methacrylate groups tartaric acid water camphorquinone
RMGI DUAL CURE SETTING REACTION
camphorquinone and blue light =polymerisation = free radical methacrylate reaction = forms resin matrix (initial set)
acid base reaction happens the same as GIC (24 hours)
RMGI TRI-CURE SETTING REACTION
camphorquinone and blue light =polymerisation = free radical methacrylate reaction = forms resin matrix (initial set)
acid base reaction happens the same as GIC (24 hours)
PLUS
REDOX reaction ‘dark cure’ (5 mins)
TYPES OF RMGI
fuji
vitrebond
USES OF RMGI
dressings fissure sealants endo access cavity temp fillings luting ortho cement restorations base/lining - vitrebond
COMPONENTS OF CALCIUM HYDROXIDE PASTE 1 - BASE
calcium hydroxyide
zinc oxide
zinc stearate
ethyl toluene sulphonamide
COMPONENTS OF CALCIUM HYDROXIDE PASTE 2 - THE CATALYST
glycol salicylate
titanium dioxide
calcium sulphate
calcium tungstate
SETTING REACTION OF CALCIUM HYDROXIDE
acid base reaction
chelation reaction between zinc oxide and the glycol disalicylate makes a cement with pH 12
HOW TO MIX CALCIUM HYDROXIDE
pea size of base and catalyst pastes
mix until uniform colour
wipe spatula clean
USES OF CACLIUM HYDROXIDE
cavity liner
direct pulp cap
USES OF ZOE
cavity liner / base in deep cavities under amalgam
temp restorations
root canal sealer
periodontal dressings
SETTING REACTION OF ZOE
acid base reaction
chelation of zinc oxide with eugenol = zinc eugenol matrix
PROBLEMS WITH LIGHT CURING
safety - exothermic reaction could damage pulp
thermal trauma to soft tissues if optic rod not placed correctly
ocular damage to operator
bad set in larger increments than DOC
ADVANTAGES OF LIGHT CURE
extended working time restoration doesn't require finishing demand cure less waste 1 paste = less porous / higher filler
DENTINE BONDING PROCESS
etch = remove smear and expose dentinal tubules, increased wetability
prime and bond = primes hydrophilic end - binds to hydrophilic dentinal tubules and the hydrophobic methacrylate binds to the hydrophobic adhesive
CONTENTS OF PRIME AND BOND
HEMA bisGMA - bound by an initiation reaction camphorqunione acetone
WHAT IS DOC
depth of cure
80% hardness of surface
HOW THICK SHOULD A CAVITY LINER BE
0.5MM
ADVANTAGES OF A CAVITY LINER
protect pulp from heat and chemicals
improve bond in adhesive restorations
antibacterial
palliate - reduce px symptoms
