Throughout the programme, there have been many different versions of the sonic screwdriver, as with subsequent Doctors the design of it was changed. It has also been destroyed on a number of occasions, thus leading to the introduction of the next model. Not all iterations of the Doctor have used the sonic screwdriver on screen; the Fifth Doctor in fact opted not to replace his after it was destroyed in "The Visitation".
Throughout the programme, there have been many different versions of the sonic screwdriver, as with subsequent Doctors the design of it was changed. It has also been destroyed on a number of occasions, thus leading to the introduction of the next model Not all iterations of the Doctor have used the sonic screwdriver on screen; the Fifth Doctor in fact opted not to replace his after it was destroyed in "The Visitation".