Nolla's Stages of Tooth Development

Nolla in 1952 described the various stages of tooth development which are as follows:

Stage 0 - Absence of crypt
Stage 1 - Presence of crypt
Stage 2 - Initial calcification
Stage 3 - 1/3rd of crown completed
Stage 4 - 2/3rd of crown completed
Stage 5 - Crown almost completed
Stage 6 - Crown completed
Stage 7 - 1/3rd of root completed
Stage 8 - 2/3rd of root completed
Stage 9 - Root completed, apex open
Stage 10 - Apical end of root completed, apical foramen closed

Nolla's stages of Tooth Development