Gear Tooth Damage!

[MonsterMadMarty]

I've started to put apart a spare 900 engine I have lying around! I was hoping to avoid pulling the cases apart but I think I may have to 

While inspecting the gears the large gear closest to the alternator side (I think it may be second gear but I'm no expert!) has three teeth in a row with damage! Do I need to split the case and replace?

[brad black]

they're just worn out.