What is the setting reaction of GIC?

Chemistry and setting reaction. All GICs contain a basic glass and an acidic polymer liquid, which set by an acid-base reaction. The polymer is an ionomer, containing a small proportion – some 5 to 10% – of substituted ionic groups. These allow it to be acid decomposable and clinically set readily.

What is the reaction type of glass ionomer cement?

Glass ionomer cements The powder of a number of glass components mixes with the liquid of polyalkenoic acid to form a paste, then the acid-base reaction starts and stiffens the paste.

How does GIC bond to tooth?

As a restorative material, GIC bond to the enamel and dentin via ionic and polar bonds, and the intimate molecular contact facilitates ion exchange of fluoride with the hydroxyl ions in the apatite of the surrounding enamel5,39.

What is the mixing time of GIC?

Mix the cement. Carefully shake the liquid and dispense one drop. Mix the two by gently folding the powder into the liquid; mixing should take up to 15 seconds.

Why do we apply Vaseline after GIC restoration?

Similarly petroleum jelly also impedes the fluoride release, but to a very less extent. We suggest that in situations where the fluoride release property is more important than other properties it is better to coat the GIC with petroleum jelly or leave the restoration without any coating.

How does GIC release fluoride?

Fluoride release from GICs restorations following a continuous uptake process increases the fluoride concentration in saliva and in adjacent hard dental tissues. Thus, continuous small amounts of fluoride surrounding the teeth decreases demineralization of the tooth tissues.

How does GIC bond to composite?

It is recommended that a bonding adhesive be applied after acid etching chemically curing GICs in order to achieve a bond to composite resin. The light curing GIC should not be etched with phosphoric acid and is the material of choice as it is both stronger and less technique sensitive than the chemically curing GICs.

What is powder liquid ratio of GIC?

The wide variations practiced in P/L mixing ratios against the recommended ratio for restorative purpose (approximately 1:2) and that for luting purpose (~1:1 to 2:1) may affect the performance characteristics of the material.

How long does GIC release fluoride?

By means of a fluoride sensitive electrode, the fluoride release from disk-shaped specimens was determined periodically over 3 years. The glass ionomer cement released the most fluoride (1.54 +/- 4 microg/cm2 after 1 year and 248 +/- 7 microg/cm2 after 3 years).