Baptism is an act of obedience to the Lord after salvation; although baptism is closely associated with salvation, it is not a requirement. Jesus Christ commands baptism for His followers, and although the act alone does not cause eternal salvation, we as followers of Christ should want to imitate our Savior and His actions through baptism.
Baby Dedication is not a Baptism, and it does not impart salvation to the child. Baby dedications are viewed as a confirmation between the parents and the church to raise the child in a Godly way until the child is old enough to make his/her decision in accepting Christ as his/her personal Savior. The dedication of Children is taught in the Bible. As a baby, Jesus was dedicated by his parents. Jesus also bestowed blessings on the children. (Mark 10:16)