Calcium hydroxide is a powder which is commonly mixed with a physiological saline to form a paste (pH 12.5) and it has a hard tissue inducing effect. When applied to the pulp, it shows no or minimal inflammatory reaction. Calcium hydroxide has anti-bacterial properties and has a limited shelf life as they eventually turn into calcium oxide. This can be used as liners or bases, for indirect and direct pulp cupping, root canal dressing, root canal sealant, apical closure. Calcium hydroxide induces the deposition of mineralized tissue which is essentially significant because it establishes biological compatibility of the product. The present paper presents a concise overview of the different applications of calcium hydroxide and provides a brief review of previous literature works.