Table 2. Changes in arch circumferences and the AALL according to increases in COS depth using the cusp tips as reference points.

AALL, The amount of additional arch length required for leveling the COS; COS, curve of Spee; 3D, three-dimensional; 2D, two-dimensional; AALLct, AALL measured from cusp tips.

^*Average of the right side and left side COS depths.