Bone grafting is used to regenerate or "regrow" tissue (also known as guided tissue regeneration). These techniques restore and strengthen the support of the teeth so they can function longer. There are many new technologies available to enhance bone regeneration. Angular bone defects and pockets 8mm or deeper usually require regeneration therapy. Bone grafting is generally done in conjunction with osseous or flap surgery. Biologics are products similar to stem cell therapy and include Emdogain, Gem – 21s or Amniocell that can improve the results of bone grafting.