Maxillary distraction osteogenesis to treat maxillary hypoplasia: comparison of an internal and an external system.

Background: Distraction osteogenesis (DO) has become a mainstream surgical technique for patients with jaw deformities. In cases of maxillary hypoplasia, DO with a rigid external distraction (RED) system has been used for maxillary advancement; however, DO with internal devices is currently popular.

Materials: This article describes DO with an internal device and a RED system in 2 patients with maxillary hypoplasia with oligodontia.

Possible roles of Runx1 and Sox9 in incipient intramembranous ossification.

Unlabelled: We evaluated the detailed expression patterns of Runx1 and Sox9 in various types of bone formation, and determined whether Runx1 expression was affected by Runx2 deficiency and Runx2 expression by Runx1 deficiency. Our results indicate that both Runx1 and Sox9 are intensely expressed in the future osteogenic cell compartment and in cartilage. The pattern of Runx1 and Sox9 expression suggests that both genes could potentially be involved in incipient intramembranous bone formation during craniofacial development.

Connective tissue growth factor mRNA expression pattern in cartilages is associated with their type I collagen expression.

Connective tissue growth factor (CTGF) has been identified as a secretory protein encoded by an immediate early gene and is a member of the CCN family. In vitro CTGF directly regulates the proliferation and differentiation of chondrocytes; however, a previous study showed that it was localized only in the hypertrophic chondrocytes in the costal cartilages of E 18 mouse embryos. We described the expression of CTGF mRNA and protein in chondrocytes of different types of cartilages, including femoral growth plate cartilage, costal cartilage, femoral articular cartilage, mandibular condylar cartilage, and cartilage formed during the healing of mandibular ramus fractures revealed by in situ hybridization and immunohistochemistry.