Yes, the two injuries are different and require specific management, depending on which it is.
A separated shoulder is an injury to the joint where three bones meet: the clavicle (collarbone), the scapula (shoulder blade), and the humerus (the upper arm bone). In the natural position, the humerus fits into the socket made by the scapula and clavicle. The separation occurs when the clavicle and the scapula come together, usually as the result of a fall and a direct blow to the shoulder, or by landing on an outstretched hand. There are different levels of separation, according to the severity of the injury. Usual treatment for minor to moderate separations are ice to the joint, rest, and anti-inflammatory medications to help relieve the pain. Surgery may be considered if the patient has a very physical occupation.
When a shoulder is dislocated, rather than separated, the humerus comes out of the socket because there is an injury to the joint. These occur most often after a fall or through a sports-related accident. Dislocations must be treated immediately to limit the amount of damage done to the shoulder. To do this, a doctor must manually put the shoulder back into place. Because of the very painful nature of the procedure, most patients are given a sedative by intravenous so they are not awake for the procedure. A sling is then used for a while after, followed by careful physiotherapy and resumption of activities. In some cases, surgery may be required.