  We prove a priori interior $C^{2,\alpha}$ estimates for solutions of fully
nonlinear elliptic equations of twisted type. For example, our estimates apply
to equations of the type convex + concave. These results are particularly well
suited to equations arising from elliptic regularization. As application, we
obtain a new proof of an estimate of Streets-Warren on the twisted real
Monge-Ampere equation.
