You Do Need power plug adapter while traveling from Dominican Republic to Pitcairn Islands.

Here is Why You Need An Adapter

The outlet and plug type used in Pitcairn Islands is I and in Dominican Republic are A, B and C. This is how they look like.

Dominican Republic

In Dominican Republic, outlets of type A, B and C are in use.

Type A

Type B

Type C

Pitcairn Islands

In Pitcairn Islands, outlets of type I are in use.

Type I