3. Osseointegration Osteoblasts Non-collagenous matrix Mineral deposition Collagen matrix Success requires primary implant anchorage and immobilization, the formation of a clot between the surface of the implant and the osteotomy site, release of growth factors, angiogenesis and migration of osteoprogenitor cells to and deposition of bone on the surface of the implant and in the osteotomy site.
54. Risk of osteoradionecrosis Esser et al, 1997 . In this retrospective analysis, 2 patients out 60 (3.4%), developed osteoradionecrosis, both in the mandible. All patients received 6000 cGy with CRT postoperatively via opposed mandibular fields.
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56. Osteoradionecrosis Case report Three years after implant placement the patient developed an infection associated with left posterior implant. This patient received 6600 cGy for a squamous carcinoma of the lateral tongue. Three years later implants were placed. Eventually, the patient developed an osteoradionecrosis, a pathologic fracture of the mandible and subsequently the mandible was resected.
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74. Implants were placed simultaneous with tumor resection and reconstruction of this large body-symphyseal defect with a fibula free flap. The patient received 6000 cGy post operatively. Irradiation of existing implants- Backscatter
75. Several months later and just after delivery of the tissue bar, the tissues on the labial surfaces of the implants dehisced and the bone overlying the implants sequestrated leading to loss of the implants. Irradiation of existing implants- Backscatter
76. Following loss of the implants, the mucosa recovered the area. The graft remained viable and mandibular continuity was maintained. Irradiation of existing implants- Backscatter
Among the 46 subjects we had 14 subjects who complete all the treatment procedure and data collection. The mean masticatory performance prior the surgery on the defect side was 22.6% and 38.6% on the non-defect side, then decreased to 7.8% and 25.3% postsurgically. Restoration with the conventional prosthesis significantly improved performance to 20% on the defect side and 32% on the non-defect side. Following treatment with the implant-supported prosthesis masticatory performance improved significantly to 31.4% on the defect side and 39.5% on the non-defect side. At the entry level the MP was 22and38% very low