A dental articulator apparatus and method of forming dental casts utilizing a dental articulator having pivotally connected upper and lower arms that each have a ball socket which receives a ball at the outer end of a respective model anchor, the opposed end of which is cast into a dental model. The model anchor ball is adjustably secured in the ball socket of the articulator arms by a set screw coupled with a rotatable magnetic extension rod that are installed, removed, advanced, and retracted as a unit and allow relative rotation between the set screw and the extension rod to facilitate fitting and positioning the ball in the socket when the set screw is loosened, and eliminate manually installing and positioning separate small shims and plungers that can be accidentally dropped and lost.