Luting Agents

Low viscosity to allow seating of restoration Easy to mix, long working time, short setting time Marginal seal with ideally chemical bond to tooth Good aesthetics - tooth coloured, and no staining Low solubility Cariostatic and fluoride releasing to prevent secondary caries at crown margins Biocompatible so it is non toxic and wont damage the pulp Low thermal conductivity High mechanical properties e.g. CS, TS, Hardness

Dental cement - zinc phosphate GIC - conventional or RMGI Composite resin luting agents - etch and DBA

Acid base reaction of powder + liquid Powder - zinc oxide - magnesium dioxide - to give white colour - alumina and silica - mechanical properties Liquid - aqueous phosphoric acid - aluminium and zinc oxides - even setting and slows setting

Cheap Easy to mix and use Strong Low porosity and solubility

Low initial pH of 2 - pulpal irritation Exothermic setting Not adhesive to tooth or restoration, works like tile grout Not cariostatic Opaque and brittle

Similar to zinc phosphate except polyacrylic acid instead of phosphoric Bonds to tooth similar to gic Less exothermic Returns to neutral pH faster Cheap

Ion exchange with calcium in enamel and dentine Hydrogen bonding with the collagen in dentine Surface of restoration should be sandblasted to allow mechanical adhesion

Low shrinkage Long term stability Relatively insoluble once set Better aesthetics than ZnPhos Adhesive to tooth surface And metal Fluoride release Cheap

Hard to mix Hard to manipulate Soluble at lower pH Low compressive strength and modulus

It decreases setting time Longer working time Higher compressive and tensile strengths due to filler Higher bond strength to tooth Decreased solubility

HEMA hydrophilic molecule is cytotoxic HEMA swells in a wet environ meant No bond to direct restoration • basically good moisture control is needed, and all monomer needs to be set

Variant of composite filling material with smaller filler particles and lower viscosity Light or dual cure Better physical properties, lower solubility and better aesthetics

Composite bonds to composite Bond is micro mechanical to rough internal surface of inlay Also bond is chemical to remaining C=C bonds on the fitting surface of inlay Use a dual cure for inlay as light penetration will be poor

Through a wetting agent as the surface is not compatible with resin luting agents It needs to chemically bond as porcelain is brittle and will fracture if not

Used when bonding to porcelain Applied to etched porcelain surface Forms strong bond between oxide groups on the porcelain and the silane Other end has C=C bond which reacts with composite resin

Metal needs to be roughened either by etching or sandblasting Not used much now Material like MDP with acid end and C=C end. Acid end reacts with metals oxide and renders surface hydrophobic Must use dual cure resin as light can’t penetrate metal

Change to an alloy that produces an oxide layer

Panavia Metal coupling agent incorporated into the resin to simplify bonding

GIC or RMGIC

GIC

Acid base The carboxylic acid group on the GIC reacts with the metal oxide on the metal. This forms waster and a salt. The salt then reacts with the carboxylic acid to form a chemical bond to the metal surface.