Let f ∈ Z[T ] be any polynomial of degree d > 1 and F ∈ Z[X0, ..., Xn] an irreducible homogeneous polynomial of degree e > 1 such that the projective hypersurface V (F ) is smooth. In this paper we present a new bound for N (f, F, B)To do this, we introduce a generalization of the power sieve ([HB84], [Mun09]) and we extend two results by Deligne and Katz on estimates for additive and multiplicative characters in many variables.