8

ZINC SILICOPHOSPHATE

It is a combination of silicate and ZnP cement
Properties fall between those of ZnP and silicate.
pH: lower than of ZnP
and has got degree of translucency.
Anticariogenic property because of fluorides.

Zinc Polycarboxylate:

Composition:
Available as powder and liquid
Available as powder to be mixed with plain water
Powder
ZnO
MgO
Traces of other oxides


Liquid:
Polyacrylic acid
Tartaric acid
Maleic acid
Iticonic acid

• Working time : 3-6mins

• Setting time 5.5mins
• Mixing time: 30 to 60secs
• Compressive strength (24hrs): 8000psi
• Tensile strength: 900psi
• Film thickness: 21mm
• Pulp response: mild
Binds chemically to tooth structure

• Luting agent for cementation of restorations

• Thermal insulating base
Secondary uses
cementation of orthodontic appliances and intermediate restorations

Advantages over ZnP

Not irritant to pulp due to high mol. size
Binds chemically to tooth structure
Can be used safely in moderately deep cavities. No need to use cavity varnish.

ZINC OXIDE EUGENOL

Type I : Temporary luting or cementation
Type II: Permanent cementation ex: kalzinol
Type III: Intermediate restoration, thermal insulating base, temporary restoration.
Type IV: Cavity liners or subbase
Examples:
Type III: IRM
Type IV: Dycal and life

Basic Composition:

As Powder and Liquid
Powder:
ZnO- Main ingredient – 70%
White rosin – reduces brittleness of cement
Zinc acetate – improves strength
Zinc stearate – acts as plasticizer


Liquid:
Eugenol : 85%
Sedative effect to pulp
Olive Oil: 15%

Modifications in basic composition

Type II – Ethoxy benzoic acid/Resins are added increases the strength of the cement
Type III- Resin reinforced, partially polymerized surface treated with propionic acid
Increases strength and abrasive resistance
Type IV – 2 paste system. Active ingredient in both pastes is Ca OH.

Examples: Type I: Tempbond / Neogenol / Freegenol

II: Kalzinol
III: IRM
IV: Dycal

Chemistry of Setting:

ZnO + H2O Zn (OH)2
Zn hydroxide
Zn (OH)2 +2HE ZnE2 + 2H2O
Base Acid Zn – eugenolate salt

MANIPULATION

Mixed on glass slab or mixing pad. Powder is dispensed and liquid is collected just prior to the mixing. Bulk of the powder is incorporated into the mixture and spatulated with a stainless steel spatula till it becomes paste on creamy in consistency. Powder or cotton fibers can be added which will improve the retention of the cement in the cavity.

Properties:

Setting time : 4-10mins
Compressive strength (after 24hrs): 4000psi
Film thickness: 25um
Solution and disintegration: 0.04% by wt
Pulp response mild

• Temporary restoration

• Intermediate
• Temporary luting
• Permanent
• Thermal insulating base
• Pulp capping agent
•


• As root canal sealants and in RC restorations
• Periodontal dressings

CALCIUM HYDROXIDE CEMENT

Available as powder or 2 paste cements
It is available as dry powder or two paste system. Mixed either with distilled water or saline to form a paste as it can also be suspended in chloroform and conveyed to the required area with the help of a syringe

When available as 2 paste cements.

One paste
– monomer of methyl cellulose as initiator and CaOH
Other paste:
Calcium hydroxide and catalyst, when they are brought in contact methyl cellulose undergoes polymerization and porous matrix is formed
pH:11

• Mechanism of action:

• Uses:
• Cavity liner
• Pulp capping agents