We consider injective local maps from a local
domain $R$ to a local domain $S$ such that
the generic fiber of the inclusion map $R \hookrightarrow S$ is
trivial, that is, $P \cap R \ne (0)$ for
every nonzero prime ideal $P$ of $S$.
We present several examples of injective local maps
involving power series that have or fail to have this property.
For an extension
$R \hookrightarrow S$ having this property, we give
some results on the dimension of $S$; in some cases
we show $\dim S = 2$ and in some cases $\dim S = 1$.