After Kami fused with Piccolo the Earth needed a new Guardian and a new set of Dragon Balls. Goku went to Namek and Dende was chosen to become the new Guardian.
Dende's Dragon is able to more than one wish. Dende has the able to heal and has become a wise Guardian under Piccolo and Mr. Popo's guidance. Dende is very kind person and was helpful in the fight against Majin Buu.
In the English dub version of the Dragon Ball Z and Dragon Ball GT anime series by Funimation Older Dende was voiced by Justin Cook. For the Ocean Group version of Dragon Ball Z he was voiced by Andrew Francis. For the Blue Water dub of Dragon Ball GT he was voiced by Jeffrey Watson.