Introduction:
Physiological changes after tooth extraction result in progressive bone resorption and decrease in bone height and weight. Most of the dimensional changes occur during the first 3 months after tooth extraction. There are different methods and materials used for socket preservation. Recent studies showed that PRF promotes soft tissue and bone regeneration.
Case report: 
The first case was a 29-year-old female with a non-restorable upper first molar on the right side. The patient was treated with a socket preservation procedure with allograft. The second case was a 33-year-old female with a fractured upper right first premolar. This patient was treated with socket preservation procedure with PRF as a sole graft material. The third case was a 21-year-old female with fractured lower left second molar. The socket was left with blood clot only. All three of the sockets were closed primarily with nonresorbable sutures. A 3 mm diameter core biopsy was taken from each socket 4 months after the procedure. During the surgical reentry an implant was placed on all three cases and its primary stability was measured.
Conclusions:
The presented clinical case showed rapid and uncomplicated patient recovery, with very good primary implant stability. The histological findings suggest that filling a fresh extraction socket either with PRF or allograft provides a relevant solution for implant site preparation.

Histological comparison of socket preservation with PRF or allograft- A report of three cases