serrated shapening question

[blanex1]

hi, i picked up a used spyderco native 4 in part serrated blade,the steel is S30V and this would be my 1st serrated knife to date!the teeth look vary jagged ant smooth,my question is,do i need to buy some sort of diamond rod to put these teeth back in shape!the other owner said it was never sharpened !that would explain a lot,if i need to buy! witch one should i get!by the way i have the sharpmaker,it makes it sharper but dose not put the right shape back in this blade,any feed back!thank you all.