Teeth get decayed and it is important to remove the decayed material so that other teeth do not get affected. When the decayed material is removed, it is important to fill the place up with other material fillings which would help in repairing the cracked or broken teeth.
Fillings can be temporary or permanent in nature. In many cases, temporary fillings are used before the permanent ones, like in the case of gold fillings. Temporary fillings also prove to be helpful in case of root canals or in case of dental emergencies like toothache. These fillings, however, do serve emergency purposes but needs to be replaced by the permanent ones. If that is not done then your tooth can get more affected and there may arise other complications.