There is provided according to some embodiments, a system, device and method for a three dimensional (3D) intraoral scanning of at least a portion of a tooth. An intraoral scanner may include a shadow casting object extending between a light emitter and the portion of the tooth. An imaging module may image the portion of the tooth and/or the projected shadow of the shadow casting object. A method to construct a 3D model may include illuminating at least a portion of the tooth with a light emitter casting a shadow on the portion of the tooth by an object located between the emitter and the tooth imaging the portion of the tooth, including at least a part of the shadow and determining a location of a point on the tooth and related to the shadow, using the image.
