Histological Observations on Bone Healing with Bioactive Glass in Horizontal Ridge Augmentation: A Report of Four Cases

The guided bone regeneration (GBR) procedure has been used successfully when there is insufficient bone volume for implant placement 1-3) . Bone graft materials are used in conjunction with barrier membranes to improve the outcomes of GBR procedures: they stabilize the blood clot, prevent membrane shrinkage and maintain the space available for new bone formation beneath the membrane 4-6) . Autogenous bone is the preferred augmentation material but harvesting of autogenous bone requires surgery, which is associated with donor site morbidity, a long operation and high costs 7-9) . A variety of graft materials are used as alternatives to autogenous grafts 10-14) . Bioactive glass is considered an effective bone graft substitute because of its bone-binding properties 15,16) . Chemical bonds form between bone tissue and a calcium phosphate layer formed by ion exchange on the surface of bioactive glass 17-21) . Many studies have demonstrated that bioactive glass has positive effects on bone healing in human sinus floor elevation and human extraction sockets 22-24) .1) Despite the high efficacy of bioactive glass as a grafting material for sinus floor elevation, 22,24-27) histological validation of its efficacy for the treatment of horizontal ridge deficiency in conjunction with GBR is limited to a relatively short-term study (6 months) 28) . In our study, we obtained bone biopsies at various times after the operations and evaluated bone healing using histology. We evaluated the efficacy of bioactive glass particles of a narrow size range (Biogran ® , 3i Implant Innovations, Palm Beach Gardens, FL, USA) for horizontal alveolar ridge augmentation in conjunction with