OBJECTIVES: Little information is available on the molecular events that occur during graft incorporation over time. The calvarial bone (Cb) grafts have been reported to produce greater responses compared with other donor regions in maxillofacial reconstructions, but the scientific evidences for this are still lacking. The objectives of this study are (1) to study the morphological pattern of Cb onlay bone grafts and compare them with the biological events through immunohistochemical responses and (2) to establish the effects of perforations in maintaining the volume and bone density of the receptor bed. MATERIAL AND METHODS: Sixty New Zealand White rabbits were submitted to Cb onlay bone grafts on the mandible. In 30 rabbits, the receptor bed was perforated (perforated group), while for the remaining animals the bed was kept intact (non-perforated group). Six animals from each group were sacrificed at 5, 7, 10, 20 and 60 days after surgery. Histological sections from the grafted area were prepared for immunohistochemical and histological analyses. Immuno-labeling was found for proteins Osteoprotegerin (OPG), receptor activator of nuclear factor-kappabeta ligand (RANKL), alkaline phosphatase (ALP), osteopontin (OPN), vascular endothelial growth factor (VEGF), tartrate-resistant acid phosphatase (TRAP), Type I collagen (COL I) and osteocalcin (OC). The tomography examination [computerized tomography (CT) scan] was conducted just after surgery and at the sacrifice. RESULTS: The histological findings revealed that the perforations contributed to higher bone deposition during the initial stages at the graft-receptor bed interface, accelerating the graft incorporation process. The results of the CT scan showed lower resorption for the perforated group (P<or=0.05), and both groups showed high bone density rates at 60 days. This set of evidences is corroborated by the immunohistochemical outcomes indicating that proteins associated with revascularization and osteogenesis (VEGF, OPN, TRAP and ALP) were found in higher levels in the perforated group. CONCLUSIONS: These findings indicate that the bone volume of calvarial grafts is better maintained when the receptor bed is perforated, probably resulting from more effective graft revascularization and greater bone deposition. The process of bone resorption peaked between 20 and 60 days post-operatively in both groups although significantly less in the perforated group.
OBJECTIVES: Little information is available on the molecular events that occur during graft incorporation over time. The calvarial bone (Cb) grafts have been reported to produce greater responses compared with other donor regions in maxillofacial reconstructions, but the scientific evidences for this are still lacking. The objectives of this study are (1) to study the morphological pattern of Cb onlay bone grafts and compare them with the biological events through immunohistochemical responses and (2) to establish the effects of perforations in maintaining the volume and bone density of the receptor bed. MATERIAL AND METHODS: Sixty New Zealand White rabbits were submitted to Cb onlay bone grafts on the mandible. In 30 rabbits, the receptor bed was perforated (perforated group), while for the remaining animals the bed was kept intact (non-perforated group). Six animals from each group were sacrificed at 5, 7, 10, 20 and 60 days after surgery. Histological sections from the grafted area were prepared for immunohistochemical and histological analyses. Immuno-labeling was found for proteins Osteoprotegerin (OPG), receptor activator of nuclear factor-kappabeta ligand (RANKL), alkaline phosphatase (ALP), osteopontin (OPN), vascular endothelial growth factor (VEGF), tartrate-resistant acid phosphatase (TRAP), Type I collagen (COL I) and osteocalcin (OC). The tomography examination [computerized tomography (CT) scan] was conducted just after surgery and at the sacrifice. RESULTS: The histological findings revealed that the perforations contributed to higher bone deposition during the initial stages at the graft-receptor bed interface, accelerating the graft incorporation process. The results of the CT scan showed lower resorption for the perforated group (P<or=0.05), and both groups showed high bone density rates at 60 days. This set of evidences is corroborated by the immunohistochemical outcomes indicating that proteins associated with revascularization and osteogenesis (VEGF, OPN, TRAP and ALP) were found in higher levels in the perforated group. CONCLUSIONS: These findings indicate that the bone volume of calvarial grafts is better maintained when the receptor bed is perforated, probably resulting from more effective graft revascularization and greater bone deposition. The process of bone resorption peaked between 20 and 60 days post-operatively in both groups although significantly less in the perforated group.
Authors: Rodrigo Ricci Vivan; Carlos Eduardo Mecca; Claudia Cristina Biguetti; Ana Claudia Muniz Rennó; Roberta Okamoto; Bruno Cavalini Cavenago; Marco Húngaro Duarte; Mariza Akemi Matsumoto Journal: J Mater Sci Mater Med Date: 2015-12-28 Impact factor: 3.896
Authors: P R Gabbai-Armelin; M T Souza; H W Kido; C R Tim; P S Bossini; A M P Magri; K R Fernandes; F A C Pastor; E D Zanotto; N A Parizotto; O Peitl; A C M Renno Journal: J Mater Sci Mater Med Date: 2015-04-17 Impact factor: 3.896
Authors: Angela Maria Paiva Magri; Kelly Rossetti Fernandes; Lívia Assis; Nathalia Antal Mendes; Ana Lúcia Yaeko da Silva Santos; Edilson de Oliveira Dantas; Ana Claudia Rennó Journal: Lasers Med Sci Date: 2015-07-30 Impact factor: 3.161
Authors: Carla Roberta Tim; Karina Nogueira Zambone Pinto; Bruno Rafael Orsini Rossi; Kelly Fernandes; Mariza Akemi Matsumoto; Nivaldo Antonio Parizotto; Ana Claudia Muniz Rennó Journal: Lasers Med Sci Date: 2013-03-21 Impact factor: 3.161
Authors: G Castillo-Dalí; R Castillo-Oyagüe; A Batista-Cruzado; C López-Santos; A Rodríguez-González-Elipe; J-L Saffar; C-D Lynch; J-L Gutiérrez-Pérez; D Torres-Lagares Journal: Med Oral Patol Oral Cir Bucal Date: 2017-03-01