The Age Groups in NESPOS are defined according to
Szilvássy, J., 1988: Altersdiagnose am Skelett. In: Knussmann R.
Anthropologie. Handbuch der vergleichenden Biologie des Menschen, Bd.
I, 1. Teil, 423-443. Fischer, Stuttgart/New York.
Eruption of the first permanent Molar (approx. > 7 years)
Period between eruption of the first and the second
Molar (approx. > 14 years)
period between eruption of the second Molar and closure of sphenobasilar gap
First ossification of sutures and beginning of tooth abrasion (approx. 20-40 years)
proceeding ossification of sutures (approx. 40-60 years)
nearly complete smoothing of sutures, possibly closure