Disclosed herein is a microelectromechanical device that features a fixed structure defining a cavity, a tiltable structure elastically suspended within the cavity, and a piezoelectrically driven actuation structure that rotates the tiltable structure about a first rotation axis. The actuation structure includes driving arms with piezoelectric material, elastically coupled to the tiltable structure by decoupling elastic elements that are stiff to out-of-plane movements but compliant to torsional movements. The tiltable structure is elastically coupled to the fixed structure at the first rotation axis using elastic suspension elements, while the fixed structure forms a frame surrounding the cavity with supporting elements. A lever mechanism is coupled between a supporting element and a driving arm.