This document provides an overview of bone structure and function. It begins with an introduction to bone and classifications of bone. It then discusses the composition of bone, including its inorganic and organic components. Various bone cells are described, such as osteoblasts, osteocytes, and osteoclasts. The document reviews bone development processes including endochondral and intramembranous bone formation. Bone remodeling and regulation of bone cells are also summarized.

1. BONE
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Guided by:
Dr. Nidhi Dhakar
Dr. Rajat Varshney
Dr. Vinayak KM
Presented by:
Dr. Dushyantsinh Vala

2. Contents
1. Introduction
2. Classification of bone
3. Composition of bone
4. Gross bone histology
5. Bone cells
6. Regulation of bone cell formation
7. Regulation of bone cell function
8. Bone development
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3. 9. Bone remodeling
10. Alveolar bone
11. Development of alveolar process
12. Structure of alveolar bone
13. Bone stains
14. Clinical considerations
15. Therapeutic considerations
16. References
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4. Introduction
• Bone is a living tissue, which makes up the body skeleton
and is one of the hardest structures of the animal body.
• Bone possesses a certain degree of toughness and
elasticity.
• It provides shape and support for the body.
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5. • It also provides site of attachment for tendons and
muscles, which are essential for locomotion.
• It protects vital organs of the body.
• Bone serves as a storage site for minerals and provides
the medium, the marrow for the development and storage
of blood cells.
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6. Classification of bone
Based on shape
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Long bones
Short bones
Flat bones
Irregular bones
Sesamoid bones

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Based on development
Endochondral bones Intramembranous bones

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Based on microscopic structure
Immature/ Woven
bone
Mature bone
Compact
bone
Cancellous
bone

9. Composition of bone
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Bone
67% inorganic 33% organic
Hydroxyapatite
28% collagen 5% noncollagenous
proteins

10. Collagen:
• Type I collagen > 95% - principal collagen in mineralized
bone.
• Alveolar bone contain type I, type V, type III, and type XII
collagen.
• Sharpey’s fibers contain type III collagen with type I
collagen.
• Type III and XII collagen fibers are produced by fibroblast
during the formation of PDL.
• Type I, V, and XII collagen are expressed by osteoblasts.
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11. Noncollagenous proteins
• Endogenous proteins - bone cells, albumin - blood.
• Osteocalcin: first noncollagenous protein to be
recognized. Also known as Bone Gla Protein.
• It is a glycoprotein- osteoblasts and regulated by vitamin
D3 and parathayroid hormone.
• Osteopontin and Bone Sialoprotein demonstrated in
alveolar bone.
• Osteonectin: bound to collagen and hydroxyapatite
crystals.
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12. • Proteoglycans are also present in the bone matrix.
• Lysyl oxidase and tyrosine rich acidic matrix proteins
(TRAMP) are the component of demineralized bone and
dentin matrix.
• TRAMP, also known as dermatopontin, binds decorin and
TGF-beta.
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13. • Bone matrix also contains proteases, protease inhibitors
and variety of cytokines secreted by osteoblasts, that
regulate cell metabolism.
• These cells secrete several members of bone
morphogenic proteins (BMP) superfamily, including
BMP-2, BMP-7, TGF-beta, insulin like growth factors
(IGF-I and IGF-II), platelet derived growth factor increase
rapidity of bone formation and repair.
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14.  Functions of bone
• Support – forms a supporting framework, giving shape &
rigidity to the body.
• Locomotion – forms a system to which the voluntary
muscles are attached.
• Protection – serves to protect the soft & delicate tissues
of the body. Eg skull protects the brain.
• Manufacturing of blood cells – RBC are manufactured
in red bone marrow which is situated in spongy tissue at
the ends of long bones.
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15. Cells of Bone Tissue
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16. Osteoprogenitor cells
• Derived from stem cells
• Differentiate in to 4 types of cells
• Comprise periosteal and endosteal cells
• Flattened or squamous cells, light staining, elongated or
ovoid nuclei, cytoplasm acidophilic or basophilic.
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17. Osteoblasts
• Mononucleated cells
• Synthesizes collagenous and non-collagenous bone
matrix proteins
• Produce organic matrix of bone (osteoid)
• Arise from pluripotent stem cells
• Exhibit high levels of alkaline phosphatase on the outer
surface of their plasma membrane
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18. • Plump, cuboidal cells or slightly flattened cells
• Type I collagen is the dominant component of the bone
matrix
• Type V collagen and proteoglycans and several
noncollagenous proteins are present in small amounts
• In addition secrete a number of cytokines and growth
factors that help in regulating cellular function and bone
formation.
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19. • IGF-I + TGF-ß + Platelet-derived growth factor =
rapidity of bone formation and bone repair
• Parathyroid hormone, 1, 25-dihydroxyvitamin D, calcitonin,
estrogen, and the glucocorticoids = bone metabolism
• Parathyroid hormone + Vitamin D = (a)bone resorption
(at high concentration)
(b) bone formation
(at lower concentration)
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20. • Leptin, a circulating hormone :-
a) can promote and inhibit the differentiation of osteoclasts
b) promote the initiation and differentiation osteoprogenitor cells
and stimulate osteoblasts to make new bone
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22. 4/30/2015 22

23. Bone lining cells
• Derived from osteoblast
• Communicate by gap junctions
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24. Osteocytes
• Some osteoblasts become entrapped within the matrix they
secrete, whether mineralized or unmineralized, these cells then
are called osteocytes.
• More rapid bone formation more osteocytes are present per
unit volume.
• As a general rule, embryonic(woven) bone and repair bone
have more osteocytes than does lamellar bone.
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25. • Osteocytic lacunae
• Canaliculi
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27. 4/30/2015 27

28. Osteoclasts
• Multinucleated giant cells
• Derived from fusion of mononuclear hematopoietic
progenitor cell
• Large in size
• Rest in howships lacunae
• Numerous lysosomes
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29. • Howship's lacunae- shallow troughs with an irregular shape,
reflecting the activity and mobility of osteoclasts during active
resorption.
• Ruffled border- adjacent to the tissue surface, cell membrane
of the osteoclast is thrown into myriad of deep folds.
• Clear or sealing zone- attaches cells to the mineralized
surface but also isolates a microenvironment between them
and the bone surface.
• Lamina limitans- electron-dense, interfacial matrix layer,
observed between sealing zone and calcified tissue surface.
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Ruffled border

31. • Functional secretory domain- collection site of vesicles
• Basolateral surface- regulatory surface for receiving
messages from neighboring cells
• Formation of osteoclast:
• Multinucleated giant cells are derived from hemopoietic cells of
monocyte macrophage lineage.
• Earliest identifiable hematopoietic precursor that can form
osteoclast is the granulocyte-macrophage colony forming unit
(CFU-GM).
• The early precursor cells proliferate and differentiate to form
post mitotic committed precursor cells.
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32. • These committed precursor then differentiate and fuse to
form immature multinucleated giant cells.
• These are activated to form bone resorbing osteoclast.
(Cell-to-cell interaction with osteoblast stromal cells)
• The formation of osteoclast requires the presence of
RANK ligand (receptor activator of nuclear factor kB) and
M-CSF (macrophage colony stmulating factor).
• These two membrane bound proteins are produced by
neighbouring stromal cells and osteoblasts, thus requiring
direct contact between these cells and osteoclast
precursors.
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33. • M-CSF acts through its receptor on osteoclast precursors
c-Fms (colony stimulating factor 1 receptor) and thereby
provides signals required for proliferation.
• M-CSF also enhance osteoclast activity by preventing
osteoclast apoptosis.
• RANKL has been implicated in the fusion of osteoclast
precursor into multinucleated giant cells.
• Their differentiation into mature osteoclasts, their
attachment to bone surface and their activation to resorb
bone.
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• Osteoprogeine (OPG) is a member of TNF receptor
family and is expressed by osteoblasts.

35. • It recognize RANKL, and
blocks their interaction
between RANK and
RANKL, leading to
inhibition of osteoclasts
differentiation and
activation.
• The balance between
RANKL-RANK signaling
and the levels of
biologically active OPG,
regulates development and
activation of osteoclast and
bone metabolism.
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36. 4/30/2015 36

37. Regulation of bone cell
formation
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38. • Bone forming cells have a mesenchymal origin, whereas that of
osteoclasts is hematopoietic.
• Two transcription factors essential for osteoblast differentiation
from mesenchymal stem cells and their function- Runx2 and
Osterix.
• Runx2- 1) involved in osteoblast differentiation
2) control the maturation of osteoblasts and their
transition into osteocytes
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39. • Osterix may play an important role in directing precursor cells
away from the chondrocyte lineage and toward osteoblast
lineage.
• Stromal cells in the marrow cavity and osteoblasts modulate
the differentiation of osteoclasts via a secreted molecules and
via direct cell-cell interaction.
• The receptor activated nuclear factor ĸB(RANK) and its ligand
(RANKL) play major role in controlling osteoclastogenesis.
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40. Regulation of bone formation
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41. 4/30/2015 41
Parathyroid hormone (PTH) Plasma ca2+; OC fomation,
activity; OB proliferation, activity-
bone turnover;
1,25(OH)2 vitamin D , plasma ca2+; OC formation,
activity; OB proliferation, OB (
and skin cell) differentiation; required
for normal matrix mineralization;
deficiency- osteomalacia, rickets
Calcitonin plasma ca2+ in young/hypercalcaemic
animals; OC formation, activity;
‘emergency’ hormone, not much effect
in normal adults
Hormones

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Glucocorticoids Necessary for normal bone
development/function; excess-
bone loss/osteoporosis; required
for bone formation in vitro
Growth hormone Required for normal bone growth
Sex steroids (oestrogens and
androgens)
Critical long-term, beneficial effects on
bone maintenance; OC formation,
activity; OB activity; deficiency -
bone turnover, osteoporosis

43. Bone development
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Endochondral
bone
formation
Sutural bone
growth
Intramembranous
bone formation

44. Endochondral bone formation
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45. Histogenesis of hyaline cartilage
• During hyaline cartilage development, mesenchymal cells
retract their cytoplasmic extensions and assume a
rounded shape, becoming more tightly packed and
forming a mesenchymal condensation, or pre-cartilage
condensation.
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46. • The increased cell to cell contact stimulates commitment
to cartilage differentiation, which progresses from the
center outward.
• Cell at the condensation's core are the first to become
chondroblasts and secrete cartilage matrix.
• After it is surrounded by cartilage matrix, a chondroblast is
termed a chondrocyte.
• Peripheral mesenchyme condenses around the
developing cartilage mass to form the fibroblast-
containing, dense regular connective tissue of the
perichondrium.
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47. • In this type of osteogenesis, the bone formation is
preceded by formation of a cartilaginous model which is
subsequently replaced by bone.
• Mesenchymal cells become condensed at the site of bone
formation.
• Some mesenchymal cells differentiate into chondroblasts
and lay down hyaline cartilage.
• The cartilage is surrounded by membrane called
perichondrium.This is highly vascular and contains
osteogenic cells.
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48. • The intercellular substance surrounding the cartilage cells
becomes calcified due to the influence of enzyme alkaline
phosphatase secreted by the cartilage cells.
• Thus the nutrition to the cartilage cells is cut off leading to
their death. This results in formation of empty spaces
called primary areolae.
• The blood vessels and osteogenic cells from the
perichondrium invade the calcified cartilaginous matrix
which is now reduced to bars or walls due to eating away
of the calcified matrix.
• This leaves large empty spaces between the walls called
secondary areolae.
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49. 4/30/2015 49
Cartilage cells
Formation of primary areolae
Formation of secondary areolae

50. • The osteogenic cells from the perichondrium become
osteoblasts and arrange themselves along the surface of
these bars of calcified matrix.
• The osteoblasts lay down osteoid which later becomes
calcified to form a lamella of bone.
• Now another layer of osteoid is secreted and this goes on
and on.
• Thus the calcified matrix of cartilage acts as a support for
bone formation.
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51. 4/30/2015 51
Osteogenic cells arrange around the
bars of calcified matrix
Laying down of osteoid
Osteoid converted into mature bone

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53. 4/30/2015 53

54. Intramembranous bone
formation
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55. • In this type of ossification, the formation of bone is not
preceded by formation of a cartilaginous model.
• Instead bone is laid down directly in a fibrous membrane.
• The intra-membranous bone is formed in the following
manner:
• At the site of bone formation, mesenchymal cells become
aggregated.
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56. • Some mesenchymal cells lay down bundle of collagen
fibers.
• These osteoblasts secrete a gelatinous matrix called
osteoid around the collagen fibers.
• They deposit calcium salts into the osteoid leading to
conversion of osteoid into bone lamella.
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57. 4/30/2015 57
Loose mesenchymal tissue
Condensation of mesenchymal
tissue
Collagen fibers laid down
between mesenchymal cells
Some mesenchymal cells differentiate
into osteoblasts

58. • Now the osteoblasts move away from the lamellae and a
new layer of osteoid is secreted which also gets calcified.
• Some of the osteoblasts get entrapped between two
lamellae.
• They are called OSTEOCYTES.
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Osteoid secreted around the collagen fibers
Calcium secreted into the osteoid by the osteoblasts.
Osteoid is converted into lamellus of bone
Osteoblasts move away and secrete another layer
of osteoid

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60. Sutural bone growth
• Sutures play an important role in the growing face and skull.
• Found exclusively in the skull, sutures are the fibrous joints
between bones; however, sutures allow only limited movement.
• Their function is to permit the skull and face to accommodate
growing organs such as the eyes and brain.
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61. • Osteogenic layer – cambium
• Inner leaf layer – capsule
• Between these two layers is a loose cellular & vascular tissue.
• When two bones are separated e.g. the skull bones forced
apart by growing brain- bone forms at the sutural margins, with
successive waves of new bone cells differentiating from
cambium.
• Sutures have same osteogenic potential as periosteum.
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62. 4/30/2015 62

63. • Theories –
• Robinsons Alkaline phosphatase theory
• Seeding theory/ Heterogenous nucleation / Epitactic theory
• Matrix Vesicle Theory
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64. Robinsons Alkaline phosphatase theory (1923)
• According to him Alkaline Phosphatase increases local conc.
of Inorganic Phosphatase thus precipitation of Ca PO4
occurs which gets converted into Apatite.
• This mechanism is called as Booster Mechanism.
• Normal level of Alkaline po4ase 0.5 – 3.5 Bodzansky’s unit.
Alkaline Phosphatase is present in
• Cell membrane of hard tissue forming cell
• Organic matrix of hard tissue
• In matrix vesicle
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65. • Main function-
• Hydrolyses Organic phosphate
• Releases Inorganic phosphate ions at an alkaline pH
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66. Nucleation theory :
• Neumann and neumann (1953) put forward the theory of
epitactic nucleation based on the concept of seeding or
epitaxy.
• A nucleus is formed, probably in relation to collagen,
effective in aggregating calcium and phosphate ions.
• The hydroxyapetite crystal then grow spontaneously by
addition of these from the saturated surrounding fluids.
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67. Matrix vesicle theory :
• The crystals have been found to be formed in association
with matrix vesicles.
• Matrix vesicles are small membrane bound structures, 25
to 250 nm in diameter, lying free in the matrix, where
calcification is known to be underway.
• These are rounded outgrowth of cell membrane that bud
from osteoblasts, chondrocytes and odontoblasts.
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68. • The vesicles are rich in phospholipids, especially
phosphatidyl serine, a lipid with high affinity for calcium
ions.
• Vesicle also contain annexins.
• Annexins in the vesicles form a calcium channels, thus
incorporating the ion within the matrix vesicles.
• Matrix vesicles accumulated Ca++ and their membranes
furnish binding sites for the nucleation of hydroxyapatite
crystals.
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69. Gross bone histology
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70. Microscopic structure:
• The bone tissue consists of bone cells present in a bone
matrix.
• The bone matrix or the intercellular substance is made of
collagen fibers and ground substance i.e. complex
mucopolysaccharides.
• The inorganic or crystalline part of the bone comprises of
hydroxyppatite crystals.
• The bone cells are called osteocytes and are found
occupying small spaces in the matrix called LACUNAE.
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71. • The lacunae are connected to one another by a system of
canals called CANALICULI.
• Some of the canaliculi open into certain canals that
contain capillaries.
• This system of connected bone cells is the means by
which nutrients are distributed throughout the bone tissue.
• Mature bone is formed in thin layers called lamellae. The
lamellae are arranged in concentric circles called
HAVERSIAN SYSTEM.
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72. • The haversian system consist of concentric lamellae
around a canal called HAVERSIAN CANAL which
contain capillary blood vessels.
• Haversian system consists of a central canal surrounded
by concentric circles of bony lamellae.
• The lamellae in turn are made of osteocytes found within
empty spaces called LACUNAE.
• A number of canaliculi are found radiating from the
lacunae.
• Three distinct type of bony lamellae are found.
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73. 1. Circumferential lamellae
2. Concentric lamellae
3. Interstitial lamellae
• Circumferential Lamellae: They are bony lamellae that
surrounds the entire bone, forming its outer perimeter.
• Concentric lamellae: They form the bulk of the bone and form
the basic metabolic unit of the bone called osteon.
• The osteon is a cylinder of bone found oriented along the long
axis of the bone.
• Interstitial lamellae: They are lamellae that are found between
adjacent concentric lamellae.
• They are thus fillers that fill the space between the concentric
lamellae.
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74. 4/30/2015 74

75. • A number of canals are found in bone, containing blood
vessels that pass into the bone from the outside or from
the bone marrow cavity. These canals are called
VOLKMANN’S CANALS.
• Branches of blood vessels from these canal may enter the
smaller haversian canals.
• BONE MARROW is found occupying the center of the
bone. It can be of two types.
• RED BONE MARROW and YELLOW BONE MARROW
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76. • RED BONE MARROW:
• They are found in most of the bones in young individuals.
• They help in formation of R.B.C.’s and W.B.C.’s.
• In adult most of the red bone marrow gets converted into
yellow marrow.
• YELLOW BONE MARROW:
• It is a fatty marrow that does not produce red and white
blood cells.
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77. 4/30/2015 77

78. 4/30/2015 78

79. • Types of Bone Tissue: Bone tissue is classified by its
architecture as spongy or compact by its fine structure as
primary(woven) or secondary (lamellar).
• All bone tissue begins as primary bone, but nearly all is
eventually replaced by secondary bone.
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80. • The distinction between intramembranous and
endochondral bone is based on histogenesis but is not
microscopically detectable in mature bone.
• Compact bone is usually long (like a femur) and white.
• It is a hard bone, that makes up the outer covering of the
bone.
• It is composed of multiple osteon unit that are bunched
closely together like stacked logs and, thus, is good at
bearing weight in the long direction.
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81. • Spongy bone is softer bone, with holes in it.
• It is found inside the bone.
• Indvidual osteon like struts (called trabecullae) branch in
many direction and interconnect.
• Thus, there are spaces created where red marrow exists.
• This kind of bone is good at handling stress from multiple
directions and is lighter weight.
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82. Histology of Woven bone and lamellar bone
• Two types of bone can be identified microscopically according
to the pattern of collagen forming the osteoid (collagenous
support tissue of type I collagen embedded in
glycosaminoglycan gel):
• Woven bone, which is characterized by haphazard organization
of collagen fibers and is mechanically weak
• Lamellar bone, which has a regular parallel alignment of
collagen into sheets (lamellae) and is mechanically strong
• Woven bone is produced when osteoblasts produce osteoid
rapidly, which occurs initially in all fetal bones (but is later
replaced by more resilient lamellar bone).
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83. • In adults woven bone is created after fractures or
in Paget's disease. Woven bone is weaker, with a smaller
number of randomly oriented collagen fibers, but forms
quickly; it is for this appearance of the fibrous matrix that
the bone is termed woven.
• It is soon replaced by lamellar bone, which is highly
organized in concentric sheets with a much lower
proportion of osteocytes to surrounding tissue.
• After a fracture, woven bone forms initially and is
gradually replaced by lamellar bone during a process
known as "bony substitution." Compared to woven bone,
lamellar bone formation takes place more slowly.
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84. 4/30/2015 84

85. Bone remodeling
• Bone remodeling is ongoing replacement of old bone tissue by
new bone tissue.
• Involves bone resorption, i.e. removal of minerals & collagen
fibers from bone by osteoclasts, & bone deposition, i.e.
addition of minerals & collagen fibers to bone by osteoblasts.
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86. • During the process of bone resorption osteoclast attaches to
bone surface at endosteum or periosteum & forms a leak proof
seal at the edges of its ruffled border.
• Releases protein digesting enzymes & acids, resulting in
destruction of collagen fibers & loss of minerals.
• Working together osteoclasts carve out a small tunnel in the old
bone.
• As osteoclasts move through bone, leading edge of bone is
called cutting cone, characterized by a scalloped array of
Howship's lacunae.
• Behind the cutting cone is a migration of mononucleated cells.
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87. • As these cells differentiate into osteoblasts, they produce a
coating called Cement or Reversal line.
• On top of this cement line osteoblasts lay down new bone
matrix, mineralizing it from outside in.
• The area where active formation occurs is called Filling cone.
• During production & mineralization of organic matrix – there are
periods of activity & quiescence- resulting in formation of
incremental lines. Such lines in bone are called as Resting
lines.
• In lamellar spongy bone- a half-moon resorption cavity is
created by osteoclasts& then filled in with bone matrix by
osteoblasts.
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88. 4/30/2015 88

89. 4/30/2015 89

90. Regulators of bone remodelling
SYSTEMIC FACTORS
Poly peptide hormones
• Parathyroid hormone
• Calcitonin
• Insulin
• Growth hormone
Steroid hormones
• 1,25 (OH)2 vitamin D
• Glucocorticoids
• Sex steroids
Eicosanoids
• Prostaglandins
• Leukotrienes
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91. LOCAL FACTORS:-
Cytokines
• Interleukin – 1
• Interleukin – 6
• Tumor necrosis factor (TNF)
Growth factors
• IGF – 1
• TGF β
Others
• Parathyroid hormone related peptide
• β2macroglobulin
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92. Blood supply of bone
ARTERIAL SUPPLY
• The bone is supplied by periosteal ,
metaphyseal , epiphyseal arteries.
VENOUS DRAINAGE
• By periosteal, epiphyseal,
metaphyseal veins.
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93. Nerve Supply:-
• Nerves accompany the blood vessels that supply bone.
• The periosteum is rich in sensory nerves, some of which carry
pain sensations.
• Nerves are specially sensitive to tearing & tension , which
explains the severe pain from fracture or bone tumor.
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94. Alveolar bone
• The alveolar process bone may be defined as that part of the
maxilla and the mandible that forms and supports the sockets
of the teeth.
Functions of alveolar bone:-
• Houses the roots of teeth.
• Anchors the roots of teeth to the alveoli, which is achieved by
the insertion of sharpey’s fibers into alveolar bone proper.
• Helps to move the teeth for better occlusion.
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95. • Helps to absorb and distribute occlusal forces generated during
tooth contact.
• Supplies vessels to periodontal ligament.
• Houses and protects developing permanent teeth, while
supporting primary teeth.
• Organises eruption of primary and permanent teeth.
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96. Development of alveolar process
• Near the end of second month of fetal life, the maxilla as well
as the mandible forms a groove that is open toward the surface
of the oral cavity.
• The tooth germs are also contained in this groove, which also
includes the alveolar nerves and vessels.
• Gradually bony septa develops develop between the adjacent
tooth germs, and much later, the primitive mandibular canal is
separated from the dental crypts by a horizontal plate of bone.
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97. • An alveolar process develops only during the eruption of the
teeth.
• During growth part of alveolar process is gradually incorporated
into the maxillary and mandibular body while it grows at a fairly
rapid rate at its free borders.
• During this period a tissue may develop at the alveolar crest
that combines characteristics of cartilage and bone. It is called
chondroid bone.
• The alveolar process forms with the development and the
eruption of teeth.
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98. Structure of alveolar bone
• Alveolar bone proper- a thin lamella of bone that surrounds
the root of the tooth and gives attachment to principle fibers of
the periodontal ligament.
• Supporting alveolar bone-bone that surrounds the alveolar
bone proper and gives support to the socket.
• Bundle bone- it is that bone in which principle fibers of the
periodontal ligament are anchored.
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99. • Lamina dura
• Cribriform plate
• Interdental septum
• Supporting alveolar bone consists of two parts:
1) Cortical plates
2) Spongy bone
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100. Age changes
• In older individuals:
oAlveolar socket appear jagged and uneven
oThe marrow spaces have fatty infiltration.
oThe alveolar process in edentulous jaws decreases in
size.
oLoss of maxillary bone is accompanied by increase in size
of the maxillary sinus.
oInternal trabecular arrangement is more open, which
indicates bone loss.
oThe distance between the crest of the alveolar bone and
CEJ increases with the age- approximately by 2.81 mm.
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101. Bone stains
• H and E stains
• Van Gieson
• Trichrome stains
• PAS
• Toulidine blue
• Safranin O
• Reticulin
• Von kossa silver method
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102. H & E
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103. van gieson
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104. Safranin o
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105. Von kossa silver
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106. Trichrome
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107. Trephine biopsy in myelofibrosis, stained with
reticulin
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108. Clinical considerations
• Through remodeling, the alveolar bone may become
displaced in relation to the remaining alveolar process,
thereby allowing tooth movement to take place.
• Interruptions in the continuity of the lamina dura in the
apical region of an alveolus are of diagnostic significance
in the radiographic identification of periapical lesions.
• Proximity of the alveolar bone to sinus cavities or major
nerves (mandibular nerve) may create problems during
tooth extraction or surgical interventions.
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109. • Following tooth extraction, the alveolar process tends to
resorb, a development that may compromise the
placement of endosseous dental implants and affect the
construction of removable prostheses.
• Placement of dental implants in the alveolar process, prior
to its becoming resorbed, following tooth extractions, will
markedly decrease the rate of ridge resorption.
• Fenestrations may convert to dehiscences which, in turn,
may lead to gingival recession.
• Surgical interventions may promote the conversion of
fenestrations into dehiscences, as well as the creation of
new fenestrations and dehiscences in the presence of thin
bony plates.
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110. Bone tumors
• Osteoma
• Osteoid osteoma
• Osteoblastoma
• Osteosarcoma
• Osteosarcoma of the skull
• Osteosarcoma of the jaw bones
• Periosteal Osteosarcoma
• Vertebral Osteosarcoma
• Parosteal Osteosarcoma
• Extra skeletal Osteosarcoma
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111. Bone related lesions
• Ossifying fibroma
• Fibrous dysplasia
• Osseous dysplasia
• Central giant cell lesions
• Cherubism
• Aneurysmal bone cyst
• Simple bone cyst
Disorder of bone
• Osteoporosis
• Rickets & Osteomalacia
• Osteoarthritis
• Osteomyelitis
• Osteosarcoma
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112. • Disorders Of Bone Mainly Affecting The Oral &
Maxillofacial Region Are
• Osteogenesis Imperfecta
• Cleidocranial Dysplasia
• Achondroplasia
• Osteitis Deformans (Paget’s Disease)
• Fibrous Dysplasia
• Cherubism
• Mandibulofacial Dysostosis
• Marfan Syndrome
• Down Syndrome
• Osteopetrosis
• Infantile Cortical Hyperostosis (Caffey’s Disease)
• Craniofacial Dysostosis (Crouzon Disease)
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113. Therapeutic considerations
• Autografts – utilizes patients bone, which can be obtained from
extraoral or intraoral sites.
• Allografts – obtained from another human source
• Xenografts – obtained from animal source
• Synthetic bone grafting materials
• Biologically mediated strategies
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114. References
• Tencate’s-Oral Histology. Antonio Nanci, Elsevier, seventh
edition.
• Orban,s-oral histology and embryology. GS Kumar, Elsevier,
twelfth edition.
• A colour atlas and textbook of oral anatomy histology and
embryology. B.K.B. Berkovitz, G.R. Holland, B.J. Moxham,
Wolfe, second edition.
• Theory and practice of histological techniques. John D.
Bankroft, Marilyn Gamble, Churchill Livingstone, fifth edition.
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