Osteoid

In histology, osteoid is the unmineralized, organic portion of the bone matrix that forms prior to the maturation of bone tissue. Osteoblasts begin the process of forming bone tissue by secreting the osteoid as several specific proteins. When the osteoid becomes mineralized, it and the adjacent bone cells have developed into new bone tissue.

Osteoid makes up about fifty percent of bone volume and forty percent of bone weight. It is composed of fibers and ground substance. The predominant fiber-type is Type I collagen and comprises ninety percent of the osteoid. The ground substance is mostly made up of chondroitin sulfate and osteocalcin.

Read more about Osteoid:  Disorders

Other articles related to "osteoid":

Intramembranous Ossification - Creation of Bone Tissue
... This matrix is osteoid and the cells that created it are osteoblasts ... lining the periphery of the nodule, continue to form osteoid at its center and some of them become incorporated within it to become osteocytes ... At this point, the osteoid becomes mineralized resulting in a nidus consisting of mineralized osteoid that contains osteocytes and is lined by active osteoblasts ...
Osteoid Osteoma - Histological Findings
... On histological examination osteoid osteoma consists of a small (< 1.5–2 cm), yellowish to red nidus of osteoid and woven bone with interconnected trabeculae, and a background and rim of highly vascularized ... is virtually indistinguishable from osteoid osteoma ... included a fibrovascular stroma with numerous osteoblasts, osteoid tissue, well-formed woven bone, and giant cells ...
Osteocyte - Origin
... behind and buried in the bone matrix as an "osteoid osteocyte", which maintains contact with the osteoblasts through extending cellular processes ... The embedded "osteoid-osteocyte" must do two functions simultaneously regulate mineralization and form connective dendritic processes, which requires cleavage of collagen and other matrix ... (osteoblastic osteocyte), type II preosteocyte (osteoid osteocyte), and type III preosteocyte (partially surrounded by mineral matrix ...
Osteoid Osteoma
... An osteoid osteoma is a benign bone tumor that arises from osteoblasts and was originally thought to be a smaller version of an osteoblastoma ... Osteoid osteomas tend to be less than 1.5 cm in size ... "Osteoid osteomas may occur at any age, and are most common in patients between the ages of 4 and 25 years old ...
Osteoid - Disorders
... nutrient minerals or osteoblast dysfunction, the osteoid does not mineralize properly, and it accumulates ... origin exhibit osteoblastic differentiation and produce malignant osteoid, which results in the formation of a malignant primary bone tumor known as osteosarcoma or osteogenic sarcoma ... This malignancy most often develops in adolescence during periods of rapid osteoid formation (commonly referred to as growth spurts) ...