INTRODUCTION: Alveolar ridge preservation strategies are indicated to minimize the loss of ridge volume that typically follows tooth extraction. Dentin and bone are mineralized tissues and almost similar in chemical components. Particulate dentin has a plenty of growth factors such as bone morphogenetic proteins (BMP) that can induce new bone formation. Platelets play a fundamental role in hemostasis and are a natural source of growth factors. Mixture of particulate dentin and platelet-rich plasma can have an osteoinductive effect during different stages of bone healing. OBJECTIVES: To investigate the biological effect of autogenous dentin graft combined with platelet rich plasma on alveolar bone healing following tooth extraction in rabbit. MATERIALS AND METHODS: Seven healthy male New Zealand rabbits weighing 3kg (±250 g) were included in this study. The upper right incisor of each rabbit was extracted .The root of each incisor was used as a source of dentin. Root dentin was ground into powder by means of mortar and pestle.2 ml blood were taken from each rabbit. Platelet rich plasma was separated from other blood components by centrifuge machine. The left and right lower first premolars were extracted at the same time .The sockets of the lower right first premolars were filled by the mixture of dentin and platelet rich plasma (study group) while sockets of the lower left premolars were left to heal spontaneously (control group). Comparison of the healing features between the two groups was made histologically and histomorhometrically after 6 weeks. RESULTS: New bone formation was noticed in the sockets loaded with dentin and platelet rich plasma mixture. The newly formed bone was significantly higher when compared to that in the control group. CONCLUSIONS combination of dentin and platelet rich plasma induces new bone formation.