Yes, 'tonttu' is often translated as 'elf' or 'gnome'. Originally, tontut were mythical guardians of places, like saunatonttu guards sauna. Later, the name started to mean Santa Claus's assistants as well. The word is hard to translate because better translations for the words 'elf' and 'gnome' do exist. Fantasy literature here uses mostly 'haltia' or 'haltija' for elf and 'menninkäinen' for gnome.

Glad you liked it.