20 - Formation, Structure + Remodelling of alveolar bone

Question 1

Alveolar bone

Answer 1

• Thickened ridge of bone containing dental alveoli (HEAD OF PAEDS’ DEFINITION)
• Compact + dense pair of bones located on maxilla + mandible that lives in the tooth socket (dental alveoli)
• This bone contains perforating fibres/Sharpey’s fibres from PDLs
• Also contains small foramina ⇢ Nerves + vessels pass through
• Bone lining socket is constantly remodelled for adaptation to occlusal stress ⇢ Newley formed bone has NO SHARPEY FIBRES
• Alveolar bone aka Lamina Dura

Question 2

Development

Answer 2

When crown root develops:

• Mesenchyme of dental sac ⇢ forms PDLS adjacent to Newley formed cementum
• Sharpey’s fibres insert into outer portion of bone + cement ⇢ provides support for developing tooth
• Mesenchyme of dental sac also forms ⇢ alveoli of alveolar bone surrounding PDL

Question 3

Formation

Answer 3

Under influence of HRS:

• Cells of outermost dental follicle differentiate ⇢ osteoblasts
• Osteoblasts ⇢ begin secretion of bone matrix + its mineralisation
• Corresponding zone of bone socket ⇢ forms in parallel to formation of root walls

Question 4

Remodelling

Answer 4

The alveolar process can be metabolised by 2 types of cells

1. Osteoblasts ⇢ cells that secrete bone matrix
2. Osteoclasts ⇢ Cells capable to digest alveolar bone ⇢ Also responsible for bone resorption