zinc polycarboxylate in dentistry

dentistry

1. Z inc P olycar oxy ate Chemical Bonding To Teeth ADA no - ? b l Formulated by D.C Smith in 1962.

2. COMPOSITION Powder Liquid Zinc Oxide 89% Magnesium Oxide 9 % Barium oxides 0.2 % Other oxides 1.4 % (Bismuth trioxide, Calcium oxide) Polyacrylic acid 32 % – 48 % carboxylic acids 30% to 55% ( itaconic acid or maleic acid ) Stannous floride

3. Available as Powder and liquid system

4. Powder particles mgo oxides zno mgo Poly acrylic acid carboxylic acids Polyacrlic acid Unreacted zinc oxide particles Matrix of Polyacrylate

5. Bonding to tooth enamel & dentin Polyacrylic acid ( polycarboxylate ) Ca ions (tooth structure)

6. PROPERTIES Excellent biocompatibility with the pulp Time (min) PH( zinc polycarboxylate ) 3.4 3.9 4.4 1hr 5.1 1 day 5.9

7. Mixing time :30-40 sec Working time : 2.5 min Setting time : Luting 6-9 min Base 3-5 min

8. COMPRESSIVE STRENGTH 55 -85 Mpa (luting) 70-95 Mpa (base)

9. 8-12 Mpa (Luting) 9-14 Mpa (base) TENSILE STRENGTH

10. MODULUS OF ELASTICITY 5-6 Gpa (Luting) 4-5 Gpa (base)

11. SOLUBILITY Luting - 0.06% Base – 0.2 %

12. Thermal properties

13. P/L ratio 1.5 gm /ml for luting 2.3 gm /ml for base

14. Instruments Glass slab or paper pad Stainless steel or plastic spatula

15. PROPORTIONING Powder is divided into 1 bulk & 2 small increments . Take 2 or 3 drops of liquid as suggested

16. Mixing is initiated by addition of bulk increment ,followed by smaller increment Mixing is done by tapping, stropping , folding or overlapping methods

17. ADVANTAGES

18. P R E S s

19. Uses