Solutions for dynamic interface

After reading the documentation, I decided to take advice. I boot menu interface elements created and populated with data from the database. I have previously worked with html and naively hoped for such behavior of the elements of unity, but it turned out otherwise. The elements are created as children remain in the hierarchy and reload the menu, they are again. How to solve this problem with minimal costs?

 IDataReader reader = db.getCurrentIslandTradeContentByZone();
 
  
  while (reader.Read())
  {
 
  Transform g = (Transform)Instantiate(_pfb_Buy, _pfb_Buy.position, _pfb_Buy.rotation);
  g.transform.parent = _parent_link;
  g.transform.localScale = new Vector3(1, 1, 1);
 
 }

This is an example of how to create Startup menu items.