D3310: Endodontic therapy, anterior tooth (excluding final restoration)
D3320: Endodontic therapy, bicuspid tooth (excluding final restoration)
D3330: Endodontic therapy, molar (excluding final restoration)
D3331: Treatment of root canal obstruction; non-surgical access
D3332: Incomplete endodontic therapy; inoperable, unrestorable or fractured tooth
D3333: Internal root repair of perforation defects
D3346: Retreatment of previous root canal therapy - anterior
D3347: Retreatment of previous root canal therapy - bicuspid
D3348: Retreatment of previous root canal therapy - molar