A circular knitting machine to produce knitted or hosiery items, comprising: - a supporting structure; - at least one needle-holding cylinder turnably mounted in said supporting structure and selectively turnable around an axis of rotation of the knitting machine; - a plurality of cylinder needles supported by said needle-holding cylinder and movable in respective sliding seats of the needle-holding cylinder so as to produce a knitted fabric; - a dial assembly arranged above said needle-holding cylinder and comprising: - a supporting ring integral with said supporting structure and coaxial with said needle-holding cylinder; - a needle-holding plate turnably mounted to said supporting ring so as to be able to turn around a respective axis of rotation corresponding to said axis of rotation of the knitting machine; - a plurality of plate needles supported by said needle-holding plate and movable in respective sliding seats of the needle-holding plate so as to produce a knitted fabric; - a plurality of control cams controlling the plate needles, placed on said supporting ring and configured for interacting with the plate needles and transmit to them, during the rotation of the needle-holding plate, a radial movement inside the respective sliding seat, approaching or away from the axis of rotation, based on a given law of motion, wherein said control cams globally form a cam profile developing around the axis of rotation, with which the plate needles interact sequentially, said cam profile defining said given law of motion; - at least one stitch cam, separate and distinct from said plurality of control cams controlling the plate needles, placed movably on said supporting ring and configured for interacting with the plate needles in a given angular sector during the rotation of the needle-holding plate around said axis of rotation; wherein said stitch cam is independently movable with respect to said cam profile, i.e. the stitch cam can be moved while said plurality of control cams controlling the plate needles is kept still with respect to the supporting ring; the circular knitting machine being characterized by said stitch cam being configured for transmitting to the plate needles a return motion approaching the axis of rotation (x), in a given angular position so as to execute stitch formation. - a supporting structure; - at least one needle-holding cylinder turnably mounted in said supporting structure and selectively turnable around an axis of rotation of the knitting machine; - a plurality of cylinder needles supported by said needle-holding cylinder and movable in respective sliding seats of the needle-holding cylinder so as to produce a knitted fabric; - a dial assembly arranged above said needle-holding cylinder and comprising: - a supporting ring integral with said supporting structure and coaxial with said needle-holding cylinder; - a needle-holding plate turnably mounted to said supporting ring so as to be able to turn around a respective axis of rotation corresponding to said axis of rotation of the knitting machine; - a plurality of plate needles supported by said needle-holding plate and movable in respective sliding seats of the needle-holding plate so as to produce a knitted fabric; - a plurality of control cams controlling the plate needles, placed on said supporting ring and configured for interacting with the plate needles and transmit to them, during the rotation of the needle-holding plate, a radial movement inside the respective sliding seat, approaching or away from the axis of rotation, based on a given law of motion, wherein said control cams globally form a cam profile developing around the axis of rotation, with which the plate needles interact sequentially, said cam profile defining said given law of motion; - at least one stitch cam, separate and distinct from said plurality of control cams controlling the plate needles, placed movably on said supporting ring and configured for interacting with the plate needles in a given angular sector during the rotation of the needle-holding plate around said axis of rotation; wherein said stitch cam is independently movable with respect to said cam profile, i.e. the stitch cam can be moved while said plurality of control cams controlling the plate needles is kept still with respect to the supporting ring; the circular knitting machine being characterized by said stitch cam being configured for transmitting to the plate needles a return motion approaching the axis of rotation (x), in a given angular position so as to execute stitch formation.