Perikymata are the external surface manifestations of
The number of perikymata gradually decreases form cervical region to occlusal or incisal region because of undisturbed development of enamel prior to birth. Perikymata are usually absent in prenatally developed occlusal parts of deciduous teeth, whereas they are present in postnatal cervical parts.
Enamel rods
Incremental lines of retzius
Nasmyth's membrane
Pellicle