Development of a bioactive cellulose membrane from sea squirt skin for bone regeneration - a preliminary research

OBJECTIVES: To develop a bioactive membrane for guided bone regeneration (GBR), the biocompatibility and bone regenerating capacity of the cellulose membrane obtained from the Ascidians squirt skin were evaluated. MATARIALS AND METHODS: After processing the pure cellulose membrane from the squirt skin, the morphological study, amino acid analysis and the immunoreactivity of the cellulose membrane were tested. Total eighteen male Spraque-Dawley rats (12 weeks, weighing 250 to 300g) were divided into two control (n=8) and another two experimental groups (n=10). In the first experimental group (n=5), the cellulose membrane was applicated to the 8.0 mm sized calvarial bone defect and the same sized defect was left without cellulose membrane in the first control group (n=4). In the another experimental group (n=5), the cellulose membrane was applicated to the same sized calvarial bone defect after femoral bone graft and the same sized defect with bone graft was left without cellulose membrane in the another control group (n=4). Each group was sacrificed after 6 weeks, the histological study with HandE and Masson trichrome stain was done, and immunohistochemical stainings of angiogenin and VEGF were also carried out. RESULTS: The squirt skin cellulose showed the bio-inductive effect on the bone and mesenchymal tissues in the periosteum of rat calvarial bone. This phenomenon was found only in the inner surface of the cellulose membrane after 6 weeks contrast to the outer surface. Bone defect covered with the bioactive cellulose membrane showed significantly greater bone formation compared with control groups. Mesenchymal cells beneath the inner surface of the bioactive cellulose membrane were positive to the angiogenin and VEGF antibodies. CONCLUSION: We suppose that there still remains extremely little amount of peptide fragment derived from the basement membrane matrix proteins of squirt skin, which is a kind of anchoring protein composed of glycocalyx. This composition could prevent the adverse immunological hypersensitivity and also induce bioactive properties of cellulose membrane. These properties induced the effective angiogenesis with rapid osteogenesis beneath the inner surface of cellulose membrane, and so the possibilities of clinical application in dental field as a GBR material will be able to be suggested.

An immunohistochemical study on calcifying tissues of the florid cemento-osseous dysplasia easily involving chronic diffuse sclerosing osteomyelitis

Florid cemento-osseous dyspalasia (FCOD) is a benign, non-neoplastic lesion characterized by multiple sclerosing masses only within jawbones. It is frequently confused with chronic diffuse sclerosing osteomyelitis (CDSO) in previous literatures. In our study, two cases of FCOD were examined to know the characteristics of their calcifying tissues. The first case was non-infected, while the second case was severely infected, displaying the typical features of CDSO in clinico-radiologic findings. The infected FCOD case showed a lot of bacterial colonies in the main lesion with relatively rare inflammatory reaction. The globular cementum-like materials of FCOD showed woven bone pattern and was positive for Alcian blue stain, and also positive for the antibodies of ameloblastin, bone morphogenetic protein (BMP) -2 and -4. On the other hands, in the immunostains of matrix metalloproteinase (MMP) -3, -9, -10, and TNF- alpha, macrophage infiltrated in the FCOD lesion was rarely observed. These data suggest that the cementum-like materials of FCOD contain various matrix proteins, and that the cementum-like materials are relevant to the overgrowth of the bacterial colonies by inhibition of the regional inflammatory reactions.

Metastatic Leiomyosarcoma of the Oral Cavity

No abstract available.