Calcium Hydroxide Uses

Calcium Hydroxide

 

Calcium hydroxide is a relatively weak cement. Due to its alkaline nature, it also serves as a protective barrier against irritants from certain restorations.

Applications / Uses of  Calcium hydroxide:

• For direct and indirect pulp capping.
• As low-strength bases-beneath silicate and composite restorations for pulp protection.
• Apexification procedure in young permanent teeth where root formation is incomplete.
• Used as a liner.

Calcium Hydroxide Applications

Composition of Calcium hydroxide:

Base Paste:

• Glycol salicylate—40%
• Calcium sulfate
• Titanium dioxide—inert fillers, pigments
• Calcium tungstate or barium sulfate—provides radioopacity

Catalyst Paste of  Calcium hydroxide:

Setting Reaction of Calcium Hydroxide:

Calcium hydroxide reacts with l-methyl trimethylene salicylate ester to form a chelate viz. amorphous calcium salicylate. Zinc oxide also takes part in this reaction.

Ca(OH)₂+ l-methyl trimethylene salicylate → calcium salicylate

Uses Of Calcium Hydroxide In Dentistry

Properties Calcium hydroxide:  Calcium hydroxide cements have poor mechanical properties.

• Mechanical Properties:
  • Compressive strength: 10-27 MPa after 24 hours.
  • Tensile strength: 1 MPa is low.
  • Modulus of elasticity: 0.37 GP
• Thermal Properties: If used in sufficient thick layers they provide some thermal insulation.
• Solubility and Disintegration: The solubility in water is high 0.4 to 7.8%.

Calcium Hydroxide Benefits

• Biological Properties:
  • Effect on pulp: The cement is alkaline in nature. The high pH is due to the presence of free Ca (OH)₂ in the set cement. The pH ranges from 9.2 to 11.7.
  • Formation of secondary dentine: The high alkalinity and its consequent antibacterial and protein lysing effect help in the formation of reparative dentine.