16.1.3 POJA-L7040+7041 Woven bone (or primary bone) 1
16.1.3 POJA-L7040+7041 Woven bone (or primary bone) 1
16.1.3 POJA-L7040+7041 Woven bone (or primary bone) 1
Title: Woven bone (or primary bone) 1
Description:
(A): Scheme and (B) human foetus, Azan stain; Petrous part of the temporal bone. Both photographs show the matrix of randomly collagen fibres with numerous small osteocytes embedded in a less mineralised extracellullar matrix (osteoid), called woven bone.
In the process of membranous osteogenesis mesenchymal osteoblasts surround themselves circumferentially with collagen in a random array to form woven bone. Next, surface osteoblasts align themselves in a linear array on the woven bone surface, subsequently a collagen matrix is deposed in a parallel orientation to synthesise parallel-fibred lamellar bone.
Background:
Shapiro et al. (2019) describes four specific stages of woven bone formation.
The osteoid is composed of:
See reference:
See also:
Keywords/Mesh: locomotor system, foetus, bone, woven bone, lamellar bone, osteoid, osteoblast, collagen, POJA collection, histology
Title: Woven bone (or primary bone) 1
Description:
(A): Scheme and (B) human foetus, Azan stain; Petrous part of the temporal bone. Both photographs show the matrix of randomly collagen fibres with numerous small osteocytes embedded in a less mineralised extracellullar matrix (osteoid), called woven bone.
In the process of membranous osteogenesis mesenchymal osteoblasts surround themselves circumferentially with collagen in a random array to form woven bone. Next, surface osteoblasts align themselves in a linear array on the woven bone surface, subsequently a collagen matrix is deposed in a parallel orientation to synthesise parallel-fibred lamellar bone.
Background:
Shapiro et al. (2019) describes four specific stages of woven bone formation.
- Stage I, early differentiation of pre-osteoblasts from undifferentiated mesenchymal cells.
- Stage II, osteoblasts surrounding themselves in a 360° arc with randomly oriented matrix fibres.
- Stage III, woven matrix acting as a scaffold on which surface osteoblasts begin to synthesise bone in parallel-fibred lamellar conformation.
- Stage IV, progressive relative diminution of woven bone in the woven bone/lamellar bone complex.
The osteoid is composed of:
- type I collagen (90%),
- glycoproteins and proteoglycans
- non-collagen proteins including:
- bone morphogenetic protein (may initiate bone formation),
- adhesion proteins (fibronectin, osteopontin, thrombospondin),
- calcium binding proteins (osteonectin, bone sialoprotein),
- mineralisation proteins (osteocalcin), enzymes (collagenase, alkaline phosphatase)
See reference:
- WOVEN BONE OVERVIEW: STRUCTURAL CLASSIFICATION BASED ON ITS INTEGRAL ROLE IN DEVELOPMENTAL, REPAIR AND PATHOLOGICAL BONE FORMATION THROUGHOUT VERTEBRATE GROUPS F. Shapiro1,* and European Cells and Materials Vol. 38 2019 (pages 137-167) DOI: 10.22203/eCM.v038a11.Y. Wu1
See also:
Keywords/Mesh: locomotor system, foetus, bone, woven bone, lamellar bone, osteoid, osteoblast, collagen, POJA collection, histology