The dentists are making good progress in developing tissue engineering techniques: "Italian scientists claim to be the first to have succeeded in using implants of dental pulp stem/progenitor cells (DPCs) for autologous [facial] bone regeneration in humans. Their technique was used to repair bone defects due to wisdom tooth problems in 17 patients. ... researchers suggest that the approach could also be applied to any other area of reconstructive and orthopedic surgery. ... The human trial [involved] the extraction and expansion of DPCs from the maxillary third molars (wisdom teeth) of 17 patients requiring wisdom tooth extraction. The cells were then seeded onto a collagen sponge scaffold. The resulting biocomplex was used to fill in the injury site left by the removed tooth. X-ray evaluation three months after autologous DPC grafting confirmed that the alveolar bone of treated patients had optimal vertical repair and complete restoration of periodontal tissue back to the second molars. Histological observations also demonstrated the complete regeneration of bone at the injury site. Optimal bone regeneration was evident one year after grafting."