A disease which only affects the formation and eruption of the tooth but does not cause  
hypoplasia is?
Hyperthyroidism does not cause hypoplasia.
In children, shedding of the deciduous teeth occurs earlier than normal, and eruption of the permanent teeth is greatly accelerated.
Ref: Shafer's textbook of oral pathology 7th edition page 652
Hyperthyroidism
Hypothyroidism
Vitamin A deficiency
All of the above