Administration of teriparatide improves the symptoms of advanced bisphosphonate-related osteonecrosis of the jaw: preliminary findings

Teriparatide is a synthetic polypeptide hormone that contains the 1-34 amino acid fragment of the recombinant human parathyroid hormone that stimulates bone formation. Currently, it is approved only for the treatment of osteoporosis. The outcomes of daily teriparatide injections for the treatment of bisphosphonate-related osteonecrosis of the jaw in 10 patients are reported here. Two of the 10 cases dropped out due to adverse events. Of the remaining eight cases, seven exhibited clinical improvement of the jaw-related symptoms of osteonecrosis and progression of the sequestration, while one case did not show improvement of the symptoms. Administration of teriparatide in patients with osteonecrosis of the jaw promotes bone formation and subsequent sequestration over a short period of time. These results suggest that adjunctive teriparatide therapy is a viable and effective option for treating osteonecrosis of the jaw.

Bone Marrow-derived Cell Therapy for Oral Mucosal Repair after Irradiation

Oral mucositis (ulcer) is a serious and painful side effect for patients with head and neck cancer following radiation therapy. However, current clinical strategies cannot efficiently prevent the occurrence of oral mucositis. In this study, we investigated whether bone marrow-derived cells (BMDCs) prevented the occurrence and/or decreased the severity of radiation-induced oral mucositis. Fresh concentrated BMDCs from male C3H mice were transplanted intravenously into female mice after tongue irradiation. For 14 days postirradiation, the changes of body weight and the time courses of ulceration were observed. Until the ulcer reached maximum size (7 days postirradiation), macroscopic and histologic analyses of harvested tongues were performed to detect the behavior of donor BMDCs. Between 2 and 5 days postirradiation, BMDCs-transplanted mice showed more expression of stem cell markers (c-Kit, Sca-1) and EGFR and fewer apoptotic cells when compared with nontransplanted control mice (irradiation group). On day 7, there were fewer and smaller ulcers observed in the BMDCs-transplanted group. Tongues of these mice had preserved their epithelial thickness, and regenerative activities (blood vessels formation, cell proliferation) were higher than they were in the irradiation group. Fluorescently labeled BMDCs were not detected in tongue epithelium but rather in connective tissue (dermis) just below the basal cell layer. These findings suggest that exogenous BMDCs behave to reduce radiogenic oral mucositis in a paracrine manner.

Slip-cast zirconia dental roots with tunnels drilled by laser process

Zirconia was used in this study for implant dental roots because of its superior properties over other materials used as dental roots in mechanical strength, toughness, workability, and biocompatibility. Zirconia blades were formed by the slip casting method and tunnels were drilled in the laser processing. The results indicate that (1) the slip casting method has made it possible to form a complicated artificial dental root with an accurate shape and size; (2) the zirconia blade has adequate strength in occlusion; (3) the neodymium: yttrium-aluminum-garnet (Nd:YAG) laser machine can drill many tunnels of the same size in diameter by using it repeatedly under the same conditions of power, pulse width, and focus; (4) zirconia is a recommended material for laser processing from the standpoint of toughness and less heat conductivity; and (5) the opacity of zirconia to x-ray penetration presents better observation during and after implantation than other ceramics.