Temporary admission (or temporary importation) relates to situations where non-Union goods may be brought into the EU without payment of duty (or with partial relief from customs duty) and subsequently re-exported in the same state they were in (i.e. unaltered) at the time of import. Consequently the temporary admission procedure can only be used if the goods are not intended to undergo any change, except the normal 'wear and tear' that can be expected due to their use within the EU.
End-use, on the other hand, is a customs procedure that is designed to facilitate trade. Under this procedure, goods entered for free circulation into the EU may be given favourable tariff treatment - duty exemption or a reduced rate of duty - on the condition that they are put to a specific use. As such, end-use is designed to lower or remove the duty burden on products that are imported for use in a certain industry or for a specific purpose.
Both procedures are strictly monitored by the customs authorities and require specific documentation.