Abstract: A medical device having an outer surface, at least a portion of the outer surface being provided with a continuous thread. The thread has a feature that is not constant in the portion of the outer surface. The feature that is not constant may be, for example, the spacing between turns of the thread, the height of the thread, the thickness of the thread, or the pitch of the thread. The feature that varies may vary continuously or discontinuously. The device may be, for example, a screw, a dental implant, an orthopedic implant, a maxillo-facial device, an orthodontic device, a maxillo-facial fixation screw, a nailing device, or a sinous lift device. Varying a feature of the thread allows the device to be adapted for insertion in to bone having varying properties along the length of the device.

Abstract: A medical device having an outer surface, at least a portion of the outer surface being provided with a continuous thread. The thread has a feature that is not constant in the portion of the outer surface. The feature that is not constant may be, for example, the spacing between turns of the thread, the height of the thread, the thickness of the thread, or the pitch of the thread. The feature that varies may vary continuously or discontinuously. The device may be, for example, a screw, a dental implant, an orthopedic implant, a maxillo-facial device, an orthodontic device, a maxillo-facial fixation screw, a nailing device, or a sinous lift device. Varying a feature of the thread allows the device to be adapted for insertion in to bone having varying properties along the length of the device.