<prompt> A male 45 years old wants his missing teeth to be replaced. Intraoral examination reveals Kennedy class 4 edentulous maxillary arch. Impression is made with fast setting alginate.The setting time of the material is :1.5 to 3 min3 to 4.5 min3 to 4 min2 to 4 min  <response>: A slight modification in the WP ratio or the mixing time can have marked effects on two important properties of the gel, tear strength, and elasticity; thus, the setting time is best regulated by the amount of retarder added during the manufacturing process. Usually, the manufacturers make both fast-setting alginate 1.5 to 3 min and normal-setting alginate 3 to 4.5 min to give clinicians a choice of the materials that best suit their working style.Clinicians, however, can safely influence the setting time by altering the temperature of the water.Key Concept: Fast-setting alginate has a setting time of 1.5 to 3 min. 