Alveolar Bone Flashcards
What are the characteristics and functions of Alveolar bone? (3)
- forms the alveolar processes
- forms with tooth development
- provides support for teeth (alveoli and supporting bone)
What are Osteoblasts? What is their function? (2)
- produce osteoid which subsequently calcifies
- form bone matrix that later calcifies
What are Osteoclasts? What is their function?(3)
- break down bone
- associated with bone resorption in Howships’ lacunae
- is multinucleated (releases enzymes to break down tissues, then engulfs it, then breaks it down again)
What are Osteocytes? What is their function? (2)
- osteoblasts trapped in calcified matrix (lacunae)
- inactive (still alive)
What are Lacunae? (2)
- spaces within the bone
- Howship’s: to house osteoclasts
What are Canaliculi? (3)
- narrow channels connecting lacunae (cells)
- brings O2 and nutrients via blood to osteocytes
- removes metabolic wastes
What happens to the alveolar process when there is no teeth?
There is no alveolar process formation. Resorption occurs after teeth removed.
What is the normal height of the alveolar crest of bone in relation to the teeth?
1-2 mm apical to CEJ in health. The crest of interproximal higher than facial and lingual bone/ plates
What does thickness and contour of alveolar bone depend on? (5)
- position of teeth in arch (normally conforms to contour of root)
- position of teeth in relation to each other
- angulation of root
- occlusal forces
- angle of interproximal bone depends on position of adjacent teeth
Where is Interdental Septum located? What does it consist of?
- between the roots of adjacent teeth (interproximal bone)
- is spongy bone and alveolar bone proper. Cortical on facial and lingual surfaces
- The crest of bone lies parallel to line drawn between CEJ’s (in health)
Where is Interradicular Bone? What is it?
- Found between furcation areas
- Alveolar proper adjacent to root and spongy / supporting bone
Where is Radicular bone? What is it?
- Bone facial and lingual to teeth (alveolar process on facial and lingual)
- Alveolar bone proper adjacent to roots, spongy bone (supporting) and cortical plate on outermost aspect
Where is Basal Bone? What is it?
- Bone below alveolar processes, below teeth forming base of ridges
What is cancellous (spongy) bone?
- Also called trabeculae
- Blood vessels travel through, and looks like honeycomb
- Is a supporting bone, it is located beneath everything
What is cortical bone?
- Is hard bony plate, consisting of layers of lamellae
- is the Basal bone (bottom of alveolar ridges)
- provides attachment for gingival fibers
What is Alveolar Bone Proper?
- it forms the tooth socket, where roots sit
- has holes in it, sharpeys fibers and blood vessels
- similar in appearance to cribiform plate
What forces occur to initiate or stimulate formation or resportion?
The process of teeth forming and erupting. Osteoblasts form to resorbe bone
What are the responses of alveolar bone to physiological migration? (mesial drift)
In adult dentition, slight mesial tilt of teeth in addition to wear of proximal contacts
Natural processes occur with growth and development
Resorption and formation (pressure vstension)
Is there any difference in the response to occlusal forces?
It is a constant process of formation / resorption
Balance of healthy force to maintain adequate support and structure
What is Fenestration?
When the root surface is not covered by bone.
Is an isolated area that doesn’t involve margin of bone
Is a window like structure in radicular bone
What is Dehiscence?
When the root surface is not covered by bone except it does involve marginal bone.
What is alveolar bone?
Bone surrounding and supporting teeth
What is the alveolus?
Socket – where teeth roots are located.
Which tissue is most active in apposition and resorption, cementum or bone?
Bone
What are the organic components of bone?
Osteocytes, ground substance, non-mineralized tissue
What are the inorganic components of bone?
Mineralized components - hydroxyapatite crystals.
If teeth are subjected to occlusal stress, what will happen to the supporting bone?
Will likely increase thickness and # of trabeculae
What is bundle bone?
- Is also called alveolar bone proper – also be called bundle because of fiber bundles of PDL inserting into it and bone forming around the Sharpey fibers.
- Bundle bone is often associated with added bone and remodeling around the S Fibers so in reference to later in development (ie Adult)
Which tissue contains Sharpey’s fibers, cementum or bone?
Both as they are the ‘terminal’ ends of the PDL.
What is the bone ‘area’ called that separates one socket from another? .
It is the Interdental septum
What is the bone called that separates the roots of the teeth? (or is situated between the roots)?
Interradicular *Radicular refers to root area.
What is the name of the compact bone on the buccal or lingual surface?
Cortical plates of bone
What is the purpose of the cortical plate?
Protection of all bone and CT structures deep to it, also a site for muscle attachment. *and periosteum (for CT attachment)
What is the cribriform plate or alveolar bone proper?
Bone lining the tooth Socket, is a thin compact type of bone with several holes due to sharpey’s fibers (in life)
What is the bone called when additional bone is laid down on the cribriform plate? What is it called when seen on a radiograph?
Bundle bone
Lamina dura
What type of bone lies between the cortical plate and the cribriform plate?
Cancellous / spongy bone / is the trabeculae of bone
Where is the alveolar crest of bone?
Crest of interdental septum and surrounding the tooth. Radiographically – reference is to the interdental because it is not visible facial and lingual.
What can the alveolar crest radiographically tell you about periodontal health?
Can see bone loss interproximally as well as the CEJ
