ADA Tooth Numbering SystemOnline version An introduction to ADA tooth numbering and area of mouth designations by Steven Schied 1 Tooth 1 2 Tooth 8 3 Tooth 17 4 Tooth 24 5 Tooth 25 6 Area of Mouth 01 Explanation 1 Tooth 1: upper right 3rd molar--one of the Wisdom Teeth 2 Top right incisor--one of the two front teeth on the upper arch 3 The lower left wisdom tooth--right below tooth #16 4 Tooth 17 - 24 completes the Lower Left Quadrant, aka Quad 30 5 Yep, just to the patient's right of Tooth 24 6 Teeth 1-16 are the Upper Arch: Area of Mouth 01