High-pressure mixing, dosing and recirculation head (1, 1') for injection or casting reaction molding, of the type comprising: - a head body, - a mixing chamber, formed in the head body, and in fluid communication with a supply duct, - a self-cleaning element, comprising a scraping portion, structured to slide in said supply duct, as well as an apparatus for controlling and commanding the mixing, delivery and recirculation comprising: - a plurality of sensors and transducers installed on board said mixing, dosing and recirculation head to detect and transform representative physical quantities of at least one operational status of said high-pressure mixing, dosing and recirculation head (1, 1') into electrical signals and - an electronic control and storing system adapted to control and synchronously scan said sensors and transducers and to receive and process said electrical signals indicative of said at least one operational status, at the beginning and during the operational phases of said high-pressure mixing, dosing and recirculation head (1, 1') to compare them with each other and with electrical signals representative of a predetermined reference operational status, characterized in that said high-pressure mixing, dosing and recirculation head (1, 1') comprises at least one section with significant local deformation, wherein said plurality of sensors and transducers connected with said electronic control and storing system comprises at least one strain gauge, for detecting the differential deformation of characteristic surfaces, differential deformation that is directly connectable to the force transmitted by said scraping portion and by the accumulation of reacted resin along a dragging section of said self-cleaning stem to the supply duct during its own movement. - a head body, - a mixing chamber, formed in the head body, and in fluid communication with a supply duct, - a self-cleaning element, comprising a scraping portion, structured to slide in said supply duct, as well as an apparatus for controlling and commanding the mixing, delivery and recirculation comprising: - a plurality of sensors and transducers installed on board said mixing, dosing and recirculation head to detect and transform representative physical quantities of at least one operational status of said high-pressure mixing, dosing and recirculation head (1, 1') into electrical signals and - an electronic control and storing system adapted to control and synchronously scan said sensors and transducers and to receive and process said electrical signals indicative of said at least one operational status, at the beginning and during the operational phases of said high-pressure mixing, dosing and recirculation head (1, 1') to compare them with each other and with electrical signals representative of a predetermined reference operational status, - a plurality of sensors and transducers installed on board said mixing, dosing and recirculation head to detect and transform representative physical quantities of at least one operational status of said high-pressure mixing, dosing and recirculation head (1, 1') into electrical signals and - an electronic control and storing system adapted to control and synchronously scan said sensors and transducers and to receive and process said electrical signals indicative of said at least one operational status, at the beginning and during the operational phases of said high-pressure mixing, dosing and recirculation head (1, 1') to compare them with each other and with electrical signals representative of a predetermined reference operational status, characterized in that said high-pressure mixing, dosing and recirculation head (1, 1') comprises at least one section with significant local deformation, wherein said plurality of sensors and transducers connected with said electronic control and storing system comprises at least one strain gauge, for detecting the differential deformation of characteristic surfaces, differential deformation that is directly connectable to the force transmitted by said scraping portion and by the accumulation of reacted resin along a dragging section of said self-cleaning stem to the supply duct during its own movement.