Which material is primarily used as a base or liner to encourage secondary dentin production?

Calcium hydroxide is specifically known for its ability to stimulate the formation of secondary dentin, making it the material of choice for use as a base or liner in dental procedures. When placed in a cavity preparation, calcium hydroxide provides an environment that promotes the vitality of the pulp and encourages the deposition of secondary dentin, which is a natural response of the tooth to injury or irritation.

Calcium hydroxide has unique properties that contribute to its effectiveness, including its alkalinity, which can help neutralize acids and create a more favorable environment for pulp healing. Additionally, it has antimicrobial properties, which reduces the risk of bacterial infection in the pulp. This makes calcium hydroxide particularly valuable in direct pulp capping and in situations where the pulp is at risk.

While varnish, fluoride varnish, and composite resin serve important roles in dentistry, they do not have the same specific function of stimulating secondary dentin production. Varnish is primarily used to seal dentinal tubules and reduce sensitivity but does not actively promote the growth of dentin. Fluoride varnish is effective in caries prevention and remineralization but does not directly stimulate secondary dentin. Composite resin is used primarily for restorations and does not have restorative properties related to dent