The document discusses calcium hydroxide, detailing its introduction as a 'gold standard' direct pulp capping agent and its various preparations and mechanical properties. It describes biological effects on pulp and dentin, application methods, advantages such as bactericidal properties, and disadvantages including potential for degradation and marginal failure. The document serves as a comprehensive overview of the use of calcium hydroxide in dental procedures.

1. Calcium Hydroxide

2. Contents
 Introduction
 Mechanism of action
 Preparations Of calcium hydroxide
 Mechanical properties
 Biological effects on pulp and dentin
 Applications
 Advantages
 Disadvantages
 conclusion

3.  Introduced by , -Hermann in 1921 and
 “Gold standard” for direct pulp capping agents.
 Is a white odorless powder.
 Strong base with pH 12.5

4. Mechanism of
action
Antimicrobial activity:

6.  Calcium hydroxide for pulp protection is available
.
Aqueous suspension.
Cement or liner
Filled resins
Preparations of calcium hydroxide

7. Aqueous suspensions
The solvent evaporates, leaving a layer of calcium
hydroxide.
 Eg: Pulpdent (Pulpdent, Brookline, MA, USA)
Calcium hydroxide liners:
A combination of calcium hydroxide with a varnish
to modify the viscosity and to improve handling
Eg: Hydroxline (George Taub, Jersey City, NJ,
USA).

8.  Calcium hydroxide cements are paste /paste
systems
 One paste Ca(OH)2
 Second paste –salicylate which is weak acid.
 Acid –Base reaction :They reacts with each other
to form amorphous calcium disalicylate.
 Eg : Dycal (Dentsply, Milford, DE, USA) & Life
(Kerr, Portland, OR, USA).

9. visible light-cured (VLC) calcium hydroxide
liner
 Consists of calcium hydroxide & barium sulfate
dispersed in a urethane dimethacrylate resin
containing initiators and accelerators activated by
visible light.
 Eg :Calcimol (Voco GmbH, Cuxhaven, Germany)
& Lime-lite (Pulpdent Corporation, Watertown,
MA, USA).
 They have less antibacterial activity.

10.  1. Moisten the prepared cavity.
 2. Dispense the pastes.
 3. Mix the Calcium Hydroxide.
Either the calcium applicator or the spoon excavator can
be used for mixing.
 Use a stirring motion not more than 10-15 seconds.
 pick up a portion that is about the size of the prepared
cavity.
 The tip of the spoon excavator can also be used .
 4. Place the cement.
 5. Allow the cement to set for After 30 seconds

11. Manipulation

12. Mechanical properties
 They have low elastic modulous .
 They have low compressive strength
 Low thermal conduction.
 High water solubility and water sorption

13.  Biological effects on pulp:
This property is helpful tertiary dentinogenesis.
In conventional liners .
Zone of necrosis 2mm thick .
Superficial granulation zone
Deep granulation zone
Proliferation rich zone
Normal pulp

14.  Effects on dentin :
 When placed on residual dentin it releases bound
non collagenous proteins like
 Transforming growth factor beta and glycosamino
glycans.
 They act as signal molecules which recruits
undifferentiated stem cells to the site of
inflammation.
 Then stem cells differentiate into odontoblasts
and lay down calcified bridge

15. Application
s
 Direct and Indirect pulp capping.
 Pulpotomy.
 Apexification.
 Intracanal medicamant
 Weeping canals.

16. Direct pulp capping

17. Apexificatio
n

19. Intracanal medicamants

20. Advantage
s
 Bactericidal
 Promotes healing and Repair of Pulp Dentin
Complex.
 Stops Internal Resorption.
 Neutralizes low ph of acids .

21. Disadvantage
s
• Associated with primary tooth resorption.
• May dissolve after one year with cavosurface
dissolution.
• May degrade during acid etching.
• Degrades upon tooth flexure.
• Marginal failure with amalgam condensation.
• Does not adhere to dentin or resin restoration.