Mesenchyme

(hematoxylin and eosin)

The slide shows a frontal section of a part in a fetal lower jaw. The mesenchyme is the basis of the developing jaw. It comprises certain cells and intercellular substance.

• Mesenchymal cells are fusiform or look like cells with processes
• An amorphous component is the largest part of the intercellular substance

You may distinguish the following organ rudiments, mesenchyme-derived tissues and cells on this slide:

• connective tissue of the skin and mucous membrane in the oral cavity
• fibroblasts that are fusiform cells with elongated nuclei. They produce the intercellular substance components for the connective tissue
• blood vessels #1, #2, #3, #4 contain formed elements of blood
• bone trabeculae #1, #2 of new bones are constituted by woven bone containing osteoblasts #1, #2, osteocytes #1, #2 and osteoclasts #1, #2
• hyaline cartilage with perichondrium, chondroblasts and chondrocytes
• dental papilla that is a mesenchymal rudiment of a tooth (future dentin and pulp)
• dental follicle that is an agglomeration of mesenchymal cells around a developing tooth (future cement and periodontium)