This document provides information on alveolar bone structure and composition. It discusses the different types of bone cells that make up alveolar bone, including osteoprogenitor cells, osteoblasts, osteocytes, and osteoclasts. It also describes the composition and structural elements of alveolar bone, such as Sharpey's fibers, vascular supply, gross morphology, and the periosteum and endosteum layers.

1. DEPT OF PERIODONTOLOGY
ANAMIKA KUMARI
ROLL NO. 2
BATCH “A”

2.  Bone
- Classification
- Functions
- Composition
 Alveolar Bone & Alveolar Process
 Functions of Alveolar Bone
 Structural Elements of Alveolar Bone
-Bone cells
 Osteoprogenitor cells – stem cells
 Osteoblasts – forms bone
 Osteocytes – maintains bone
 Osteoclasts – resorbs bone

3.  Sharpey’s fibers
 Vascular Supply & Lymphatic Vessels
 Gross Morphology of alveolar Bone.
 Structures of Alveolar Bone
 Periosteum & Endosteum

4.  The hard form of connective tissue that
constitutes the majority of the skeleton of
most vertebrates.
 Second only to cartilage in its ability to
withstand stress.

5. COMPACT BONE
• Composed of dense and concentrically arranged bony
trabeculae or lamella.
• More solid with fewer cavities.
• Found external to spongy bone
• Presence of haversian system.

6. SPONGY or CANCELLOUS BONE
 Composed of bone trabeculae or spicules.
 Has a simple and less organized architecture.
 Has a lattice-work pattern with numerous small cavities.
 Found internal to compact bone.
 Has no haversian system.

7. 1. Immature bone /Fibrous bone : These have
more cells & fibers in them. In humans they
are found only in fetus, sockets of alveolar
bone, sutures of the skull.
1. Mature bone /Lamellar bone: The type of
bone which are composed of thin plates
(lamellae) of bony tissue. Most mature human
bones are lamellar bones.

8. 1. Support: provides framework that supports and
anchors all soft organs.
2. Protection: skull and vertebrae surround soft tissue
of the nervous system, and the rib cage protects
vital thoracic organs.
3. Movement: skeletal muscles use the bones as
levers to move the body.
4. Storage: fat is stored in the interior of the bones.
Bone matrix serves as a storehouse for various
minerals.
5. Blood Cell Formation: hematopoiesis occurs within
the marrow cavities of the bones.

9.  65% Inorganic matter
(Hydroxyapatite)
 Mostly Calcium and
inorganic orthophosphate
deposited between collagen
 35% Organic
 28-30% collagen
 5-7% non-collagenous
proteins.
 Osteocalcin
 Bone Sialoprotein
 Phosphoprotein
 Osteonectin
 Bone morohogenic protein
Composition of bones
Inorganic
Substances
Organic
Substances

10.  2/3rd inorganic matrix
 Composed of minerals calcium & phosphate,
along with hydroxyl, carbonate, citrate &
trace amount of other ions,such as sodium,
magnesium & fluorine.

11.  Bone is formed by the
hardening of the matrix,
entrapping the cells. When
these cells become entrapped
from osteoblasts they become
osteocytes.
 The organic matrix of bone is
about:
 90% collagen
 10% non-collagenous proteins.
Organic Components of the
Bone Matrix
Collagen
Non-
collagenous
proteins

12.  Contributes towards the important
biomechanical properties of tissue in terms
of resisting loads and providing necessary
resilience that prevents fractures.
 The dominant collagen in bone is Type I.
 Intrinsic collagen
 collagen as secreted by osteoblasts.
 Extrinsic collagen
 Collagen formed by adjacent fibroblasts.

13.  are a heterogeneous group which vary from
entrapped serum protein to glycoproteins.
 play a role in mineralization.
 The main non-collagenous proteins
comprise of:
 Proteoglycans
 Osteonectin
 Glycoproteins
 Bone Sialoproteins (BSP)

15.  Alveolar bone or alveolar process is that portion
of maxilla and mandible that supports the roots of
the tooth.
 If the teeth are lost the alveolar process
disappears.
 It is composed of two parts the alveolar bone
proper and the supporting bone.

16.  Since the alveolar process develop & undergo
remodeling with the tooth formation &
eruption, they are tooth dependent bony
structures.
 The alveolar process
contains a region of
compact bone adjacent
to the periodontal
ligament called LAMINA
DURA.
 It is called processus
alveolaris in maxila and
pars alveolaris in the
mandible bone.

17.  It supports the tooth roots on the facial and
on the palatal/lingual sides.
 It is the one responsible for the separation of
teeth from mesial to distal.
 Also contributes to absorption and
distribution of occlusal pressure produced in
tooth to tooth contact.

18. 
 Bone cells
 Osteoprogenitor cells – stem cells
 Osteoblasts – forms bone
 Osteocytes – maintains bone
 Osteoclasts – resorbs bone
 Bone matrix
 Sharpey’s fibers
 Vascular Supply & Lymphatic Drainage

19.  Stem cells derived from the mesenchyme.
 Possess mitotic potential and the ability to differentiate
into mature bone cells.
 Resemble mesenchymal cells and are spindle-shaped,
with pale-staining elongated nuclei and sparse cytoplasm
(small amount of rough ER and poorly developed golgi
complex).
 Mostly found in the inner portion of the periosteum, in
the endosteum, and within vascular canals of compact
bone.

20.  Uninucleated cells .
 Synthesize both collagenous and noncollagenous
bone proteins.
 Osteoblasts also synthesize the enzyme alkaline
phosphatase, which is needed locally for the
mineralization of osteoid.
 The precursor cell of the osteoblast is the
preosteoblast.
 Osteoblasts have all the characteristics of hard
tissue-forming cells.
 When the bone is no longer forming, the surfaces
of the osteoblasts become inactive and are
called Lining cells.

21.  are osteoblasts secreted in the bone matrixes
that are entrapped in lacunae.
 An osteocyte lies in its own lacuna and
contacts its neighboring osteocytes
cytoplasmically through canaliculi.
 The most important function of osteoblast-
osteocyte complex is to prevent
hypomineralization of bone by continually
pumping calcium back to the bloodstream.

22.  Derived from a monocytic-macrophage
system, which are responsible for bone
resorbtion.
 They are multinucleated cells with fine,
fingerlike cytoplasmic processes and are rich
in lysosomes that contain tartrate-resistant
acid phosphatase (TRAP).
 Osteoclasts lie in resorbtion craters known
as Howship’s lacunae on bone surfaces or in
deep resorption cavities called cutting cones.
 These bone cells can only resorb mineralized
bone matrix.

23.  Bone matrix consists of organic and inorganic
components.
 The association of these substances gives
bone its hardness and resistance.
 The organic component is composed of
collagen fibers with predominately type I
collagen (95%) and amorphous material,
including glycosaminoglycans that are
associated with proteins.

24.  Osteoid is uncalcified organic matrix.
 Inorganic matter represents about 50% of the
dry weight of bone matrix.
 composed of abundant calcium and
phosphorus, as well as smaller amounts of
bicarbonate, citrate, magnesium, potassium,
and sodium.
 Calcium forms hydroxyapatite crystals with
phosphorus but is also present in an
amorphous form.

25.  Concentrically arranged bony
lamellae
 Types of layering (lamella)
Circumferential lamella –
external, internal
Concentric/Haversian lamella
Interstitial or Intermediate
lamella

27.  Sharpey's fibers are the
terminal ends of principal
fibers (of the periodontal
ligament) that insert into the
cementum and into the
periosteum of the alveolar
bone.
 A study on rats suggests that
the three-dimensional
structure of Sharpey's fibers
intensifies the continuity
between the periodontal
ligament fiber and the
alveolar bone (tooth socket),
and acts as a buffer medium
against stress.

28.  Alveolar process of the maxilla
 Anterior and posterior alveolar arteries (branch
from the maxilla and infraorbital arteries).
 Alveolar process of the mandible
 Inferior alveolar arteries (internal)
 Periosteal branches of submental and buccal
arteries (external).

29.  Smallest lymph vessel - Lymph capillaries.
 All third molars – Jugulodigastric lymphnodes
 Mandibular incisors – Submental lymphnodes
 Rest – Submandibular lymphnode

30. GROSS MORPHOLOGY

31.  Also called Dental
alveolus.
 are sockets in the jaws in
which the roots of teeth
are held in the alveolar
process with the
periodontal ligament.

32.  Interdental Septa
 “Septa” – in Latin, it means
“fence” or “wall”
 Are plates of bone that
separate each individual
sockets from one another.
 Inter-radicular Septa
 Are thin plates of bone
that separate the roots of
multi-rooted teeth.

33.  also called as bundle bone.
 A type of alveolar bone so called because of the
‘Bundle’ pattern caused by continuation of
principal (Sharpey’s) fibers into it.
 Is the compact layer of bone lining the tooth
socket (alveolar socket).
 Reflects the sieve-like appearance produced by
numerous Volkmann’s canals passing from the
alveolar bone to the PDL (periodontal ligament).
 Numerous Sharpey’s Fiber pass through it.

35. • Outer bony plate of varying thickness,
which is the outside wall of the
maxilla and mandible, covered with
periosteum.
• Continuous with the lamina
cribriformis at the orifice of the
alveoli – alveolar crest.
• Consists of haversian systems
(osteons) and interstitial lamellae.
• Thicker in the mandible than maxilla.
• Generally greater on the lingual than
on the buccal/facial aspect.

36.  Are spongy (or cancellous/trabecullar) bone
between the 2 bony plates and between the
lamina cribriformis of adjacent teeth or roots.
 Consists of delicate trabeculae, between
which are marrow spaces, filled mostly with
fatty marrow.
 Regions of maxillary tuberosity and the angle
of mandible.

37.  Layers of differentiated osteogenic
connective tissue covers all bone surfaces.
 Tissue covering outer surface of bone is
termed as Periosteum.
 Tissue lining the internal bone cavities is
called Endosteum.