This document provides information on enamel, the hardest tissue in the human body that covers the crowns of teeth. It discusses the physical and chemical properties of enamel, including its structure of enamel rods/prisms arranged in patterns. The development of enamel is described, with ameloblasts differentiating from epithelium and going through stages of formation, maturation, and protection before eruption. The summary concludes with key points about enamel's structure providing protection and resistance for teeth.

1. ENAMEL
Presented by:
Dr.Chandana Menon
1st year MDS
CONSERVATIVE DENTISTRY AND ENDODONTICS
1

2. TABLE OF CONTENTS:
 Definition
 Introduction
 Physical Properties
 Chemical properties
 Structure of enamel
 Surface structures of enamel
 Development of enamel
 Age changes of enamel
2

3.  Clinical considerations
 Developmental defects of enamel
 Caries and enamel
 Non carious lesions of enamel
 Effects of flouride
 Effects of laser
 Bleaching
 Adhesion to enamel
 Formulation of enamel walls
 Effects of burs
 Conclusion
3

4.  Enamel is an eccentric hard tissue because of its origin,
chemically distinct nature of the various noncollagenous
matrix proteins expressed by ameloblasts, and its large
mineral crystals
 Ectodermal , Non – collagenous, Non vital
4
tencate

5. INTRODUCTION
 Hardest calcified tissue in human body.
 Protective and resistant covering over the entire surface of
the crown.
 Ameloblast – cells responsible for formation of enamel,
are lost as the tooth erupts into the oral cavity, and hence
enamel cannot renew itself.
5

6. PHYSICAL PROPERTIES
THICKNESS:
 Increase in thickness viewed as adaptation to functional
demands.
• Maximum thickness of 2-2.5mm at cusps of
molars and premolars.
• Knife edge at the neck of the tooth
• Thicker at lingual surface of maxillary molar
and buccal surface of mandibular molars.
6

7. HARDNESS:
 Hardest calcified tissue due to high content of
mineral salts and their crystalline arrangement.
 Brittle, which is particularly apparent when the
enamel loses its foundation of sound dentin.
SPECIFIC GRAVITY : 2.8
7

8. PERMEABILITY:
 Semipermeable , permitting complete or partial passage
of certain molecules
COLOR:
 Color ranges from yellowish white to grayish white.
•Translucent and thin
enamel, visible dentin
more opaque enamel
8

9. CHEMICAL PROPERTIES:
 The enamel consist mainly of
Inorganic material (96%)
Organic material and water (4%)
 The inorganic material of the enamel is hydroxyapatite.
9

10.  The organic material consists of
Unique proteins (found exclusively in the enamel)
Lipids
The proteins found in the enamel are of two main types:
Amelogenins
Nonamelogenins
10

11. AMELOGENINS:
11
Heterogenous group of low molecular weight protein.
Accounts 90% of the enamel proteins.
Hydrophobic.
Rich in proline, histidine, glutamine and leucine

12. NONAMELOGENIN:
12
High molecular weight proteins.
Constitute about 10% of enamel matrix protein.
Enamelin, ameloblastin and tuftelin are the important
proteins of this group.
They are rich in glycine, aspartic acid and serine.

13. HYDROXYAPATITE CRYSTALS:
 The inorganic material of enamel
Chemical formula--
(Ca10(PO4)6(OH)2 )
 Crystals are Hexagonal in cross section.
13

14.  Has a central core or C axis of hydroxyl ion
around which Calcium and phosphorous ions are
arranged in triangles.
 During the formation, magnesium can replace calcium
and carbonate can replace hydroxyl ion which
destabilize the lattice.
14

15.  Fluoride may substitute hydroxyl ions. Conferring
greater stability and resistance to acidic dissolution.
 Cores of the crystallites are richer in magnesium
and carbonate. So greater solubility in acids than
the peripheral portions.
 Carbonate rich crystals are more attacked by acids
in caries
15

16. DRY WEIGHT % OF ENAMEL
OXYGEN 43.4 %
CALCIUM 36.6 %
PHOSPHORUS 17.7 %
SODIUM 0.67 %
CARBON 0.64 %
MAGNESIUM 0.35 %
16

17. WATER:
 Water is present as a part of the crystal, between
crystals and between rods and surrounding the
rods.
 Pores are present between the crystals, especially
at the boundaries of the rods and these are filled
with water.
17

18. STRUCTURE OF ENAMEL:
 The enamel is composed of
18
 Enamel rods or prisms
 Rod sheath
 Interprismatic substance

19. ENAMEL RODS / PRISMS
 HA crystals are arranged parallel to each other to
form the enamel rods/prisms.
 Number of rods
 Diameter of rods – Avg 4 micro m
- increase from DEJ to the surface (1:2)
 Runs a tortuous course from DEJ to the surface
- length of rods > thickness of enamel
19
- 5 million in lower lateral incisor
- 12 million in upper first molars

20.  In electron microscopic study
- key shaped or paddle shaped prisms
 In decalcified section of teeth
- hexagonal round or oval,
resembles fish scales
 DEJ : Arcade outline
Enamel surface :keyhole shaped outline
20

21. ROD SHEATHS
 Organic matrix forms
an envelope
surrounding each
apatite crystals
 Less calcified than
rods
 More organic matter
than the rod
21

22. INTER PRISMATIC SUBSTANCE
 Cements the rods
 Less calcified areas than the rod
 More calcified than rod sheath
22

23. STRIATIONS
 Cross striations demarcate the rod
segments
 More pronounced in insufficiently
calcified enamel
 Length – 4 micro m
 Due to diurnal rhythmic deposition of
matrix
23

24. Direction of rods
 Starts perpendicular to the surface of
dentin
24

25.  Has a wavy course from
the dentin to enamel
surface
 It’s a functional
adaptation to resist
cleavage in an axial
direction
25

26.  During cavity preparation the direction of enamel
rods should be followed
 Enamel margins should be well supported by
dentin
 Unsupported enamel margins are brittle
 Can Break & produce leakage leading to
secondary caries
26

27.  Gnarled enamel
If disks are cut in an oblique direction,
near the dentin in the region of cusps
- bundles of rods seem to intertwine
This enamel does not
yield readily to the pressure
of hand instruments
27

28. Hunter – Schreger bands
 In longitudinal ground sections under reflected light
-As alternating dark and light strips
of varying widths
 Result of change in the direction of
rods
 Composed of alternating zones
- slightly different permeability
- different content of organic material
28

29.  Starts from DEJ and ends at some distance from
the outer surface
 HSB patterns have evolved to optimise resistance
to attrition, abrasion and tooth fracture.
 Certain aspects of HSB packing densities and
distributions have beneficial roles in enamel
bonding.
Hunter–Schreger Band patterns and their implications for clinical dentistry, journal of oral
rehabilitation
29

30. Incremental lines of retzius
 In ground sections
- Brownish bands
 In transverse section
- As concentric circles
In longitudinal sections
- suround the tip of
dentin
30

31.  Due to successive apposition of layers of enamel
during formation
 Mean daily formation is 3.5 microns
 Increases from inner to outer enamel
 Metabolic disturbance may alter this rhythm
31

32. Neonatal lines
 Accentuated incremental lines
 In deciduous teeth and 1st permanent molar
 Forms the boundary of enamel formed before
birth and after birth
 Prenatal enamel is more
calcified.
32

33. Surface structures of enamel
1. Prismless enamel
 No prisms are visible (30 micro m)
 In 70% permanent & all deciduous teeth
 Heavily mineralized with more inorganic content
33

34.  Surface is denser and less permeable when
compared to prismatic enamel
 Less at the cusp tips & more cervically
34

35. 2. Perikymata
 External manifestations of striae of Retzius,
parallel to each other and CEJ.
 As transverse wave like grooves
 About 30/mm at CEJ
- reduces to 10/mm at occlusal and incisal third
 May contribute to the accumulation
of plaque
35

36. 3. Enamel Cuticle
 Primary enamel cuticle - Nasmyth’s memberane covers entire
crown of newly erupted tooth.
 Wavy course, protects enamel from resorptive activity prior to
tooth eruption
36

37.  Primary Enamel Cuticle
 Delicate membrane that covers the entire surface
of newly erupted tooth
 Is the basal lamina secreted by ameloblasts
 Soon removed after eruption, from the incisal and
occlusal thirds
37

38.  Secondary Enamel Cuticle
 Covered the cervical area of enamel
 Continuous with the cementum
 Its probably of mesodermal origin
38

39. Pellicle
 It is the precipitate of salivary proteins
 Covers the crown
 Reforms with in hours after mechanical cleaning
 It colonizes micro organism
to form a bacterial plaque
39

40. 4. Enamel lamellae
 Leaf like structures that extend from surface of
enamel towards the dentinoenamel junction.
 Hypomineralized structure
 It may be a site of weakness and forms the
road for entry of bacteria
40

41. Types of Enamel lamellae
Type A Type B Type C
Consist Poorly calcified
rod segments
Degenerated cells Organic matter
from saliva
Tooth unerupted unerupted erupted
Location Restricted to
enamel
Reach into dentin Reach into dentin
Occurrence Less common Less common More
common
41

42. 5. Enamel tufts
 Arise at DEJ & reach into enamel to about 1/5th to 1/3rd of
enamel thickness.
 Consists of hypocalcified enamel rods &
interprismatic substance.
42

43.  Ribbon-like, resemble tuft of grass
 Extend in the direction long axis
of crown
 Abundantly seen in longitudinal sections.
43

44. Dentino Enamel Junction(DEJ)
 Surface of dentin is pitted at DEJ
 Into the shallow depression of dentin, the rounded end of
enamel is fitted
 DEJ appears scalloped,
convexity directed towards dentin.
44

45.  Ridges of DEJ are more pronounced in occlussal area.
 Provide better adhesion of enamel and dentin.
45

46. Cemento Enamel junction
 The relation between enamel and cementum at the cervical
region of the tooth is variable.
 In 60% -cementum overlaps the enamel
 In 30% -cementum meets enamel in a
relatively sharp line.
 In 10% -enamel and cementum do not
meet.
46

47. 6.Enamel spindles
 Extension of odontoblastic processes across the DEJ into
the enamel.
 Appears dark in transmitted light.
 Mainly found in the cuspal region
 Hypomineralized structure
47

48. Development of Enamel
Some special features of enamel
 Enamel is the only hard tissue, which does not have
collagen in its organic matrix
 The enamel present in the fully formed crown has no viable
cells
 All the enamel is formed before eruption of teeth
48

49.  Only ectodermal derivative of the tooth
 Derived from the enamel organ
 Enamel organ is differentiated from the primitive
oral epithelium lining the stomodeum
 They also lacks the vessels and nerves
49

50. Dental lamina
 Serve as the primordium for
the ectodermal portion of
the deciduous teeth. - enamel organ
 First evidence of tooth development begins in the
sixth week in utero or three weeks after the
rupture of the bucco pharyngeal membrane.
50

51. 51
Developmental stages of teeth – Bud stage
Cap stage
Bell stage

52. Enamel organ of cap stage 52
Outer enamel epithelium
Inner enamel epithelium

53. Life cycle of Ameloblasts
(1) Morphogenic stage
(2) Organizing stage
(3) Formative stage
(4) Maturative stage
(5) Protective stage
(6) Desmolytic stage
53

54.  Before formation of enamel, the cells of
inner enamel epithelium differentiate in to
AMELOBLASTS
54

55. 1. Morphogenic stage
 Early bell stage
 Ameloblasts interact with the adjacent
mesenchymal cells
 Determination of shape of the dentino enamel
junction and the crown
 Cells are short and columnar with large
oval nuclei.
55

56. 2. Organizing stage
 Late bell stage
 The inner enamel epithelium interacts with the
adjacent connective tissue cells, which
differentiate into odontoblasts.
 Formation of dentin begins
 Cells become longer
56

57.  Migration of centrioles and Golgi regions from proximal
ends to distal end- reversal of polarity.
57

58. 3. Formative stage
 The ameloblasts enter their formative stage after the first
layer of dentin has been formed.
 Enamel formation begins.
 First layer of enamel is formed and the
ameloblasts migrate to form the Tome’s process.
58

59. 4. Maturative stage
 Enamel maturation (full mineralization) occurs
after most of the thickness of the enamel matrix
has been formed in the occlusal or incisal area.
 Matrix formation is still in progress at the cervical
area
59

60.  Ameloblasts are sightly reduced in length, spindle shaped
cells in stratum intermedium.
 Distal extremities of ameloblast display microvilli and
cytoplasmic vacuoles containing material resembling
enamel matrix indicating- absorptive function.
60

61. 5. Protective stage
 Enamel has completely developed and has fully
calcified
 The ameloblasts cease to be differentiated
 These cell layers then form a stratified epithelial
covering of the enamel
-Reduced Enamel Epithelium(REE)
61

62. Reduced Enamel Epithelium(REE)
 REE protects the enamel till eruption.
 In case of premature breakdown, CT comes in
contact with the enamel surface and deposits
cementum
62

63. 6. Desmolytic stage
 REE proliferates and induces atrophy of connective tissue
separating it from oral epithelium.
 Fusion of both epithelium takes place.
63

64. 64

65. 65
FIGURE 4.45 The life cycle of an ameloblast. The cells of the internal enamel epithelium (1) start to differentiate, beginning at the
future enamel–dentine junction of the cusp tip. The differentiating cell (2) is characterized by a reversed polarity; the cell becomes
columnar and the nucleus moves to that part of the furthest from the dentine. Secreting organelles are formed and the end of the
cell adjacent to the dentine becomes the site for secretion. At the next stage (3), the cell secretes the initial enamel component of
the enamel–dentine junction. This thin layer will be continuos with the inter-rod enamel of the later formed tissue. As the cell
retreats, the secreting pole becomes morphologically distinct as a pyramidal Tomes process (4a). Crystallites are formed at both
surfaces of the process. The proximal region between two processes, deep in the junctional regions, always secretes ahead of the
more distal region so that pits surrounded by inter-rod enamel are formed. These are then filled, giving the prism configuration to
the tissue. Simultaneous secretion of both organic material and mineral continues until the full thickness of the tissue is formed. In
this secreting phase, two appearances of ameloblasts can be distinguished by the position of the nuclei within the cell: high (4a)
and low (4b). At the beginning of secretion, half the cells are in each form. Towards the end of secretion, most of the high nuclei
have moved to a low position, effectively increasing the areas of the ameloblast cells as the surface of forming enamel increases.
When the full thickness of enamel has formed, ameloblasts lose the secretory extension, the Tomes process (5a). Up to 50% of
them die and are phagocytosed by others in the layer. The maturation phase lasts two to three times longer than the secretory
phase. During the maturation phase there is a regular, repetitive modulation of cell morphology between a ruffled (5a) and a
smooth (5b) surface apposed to the
enamel. Once the maturation changes are complete, the cells regress in height (6). At this stage, they serve to protect the enamel
surface during eruption and later will contribute to form the junctional epithelium.

66. 66
AMELOGENESIS

67.  Two processes are in involved,
1.Organic matrix formation
- Development of tomes process
- Distal terminal bars
2.Matrix mineralization and maturation
67

68. 1. Organic matrix formation
 Ameloblasts begin secretory
activity when a small amount of
dentin has been laid down
 Deposition of islands of matrix
proteins along the predentin
 Amelogenin is the major
component of enamel matrix
proteins
68

69. Tomes’ process
 Surfaces of the ameloblasts facing the
developing enamel are not smooth.
 There is an interdigitation of the cells
and the enamel rods that they produce
 The projections of the ameloblasts into
the enamel matrix - Tomes’ process
69

70. “Picket fence” arrangement of Tome’s processes.
70

71.  4 ameloblast results in the synthesis of 1 enamel
rod
Head of rod by 1 ameloblast
Tail of rod by 3 ameloblasts
 Inter rod enamel is formed by
junctional complexes and from adjacent ameloblast
71

72. 72
 Drawing illustrating one interpretation of relationships between
enamel rods and ameloblasts.
 Cross-sections of ameloblasts are indicated by thin lines
arranged in regular hexagonal array.
 Enamel rods are indicated by thicker curved black lines,
outlining keyhole- or paddle-shaped rods.
 Gray lines indicate approximate orientation of
enamel crystals, which are parallel to long axes of rods in their
“bodies” and approach a position perpendicular to long axes in
“tails.”
 One can see that each rod is formed by four ameloblasts and that
each ameloblast contributes to four different rods.
(Source: Modified from Boyde A: In Stack MV and Fearnhead RW, editors: Tooth enamel, Bristol, 1965, John Wright & Sons Ltd).

73. Distal terminal bars
 Junctional complexes encircle the distal and the
proximal end of ameloblast
 Junctional complexes at distal end – distal
terminal bar
 It separates Tome’s process from the cell proper
73

74. 2. Matrix mineralization
 Nucleation is initiated by the apatite crystallites of
dentin on which enamel is laid
 Occurs in matrix segments and interprismatic
substances are laid down.
 Initial mineral is octacalcium phosphate.
 It is unstable and one unit of it is converted to 2
units of Hydroxyapatite.
74

75. Maturation(second stage)
 Gradualcompletion of mineralization.
 Its begins before matrix has reached its full thickness
 Rods mature from - depth to surface
 The crystals increase in size from 1.5 – 25 micro m
 Loss of volume of organic matrix by withdrawal of
proteins & water
75

76. 76

77. AGE CHANGES IN ENAMEL
 Most apparent change
- Attrition, wear of occlusal & proximal surface
- loss of vertical dimension
 Anterior teeth lose rapidly than do posterior
77

78.  Changes in the organic portions
- teeth may become darker
- resistance to decay increases
 Increase in the size of the crystals
- decrease the pores between them
- greatly reduce the permeability
78

79. Some clinical considerations
Grooves & fissures
 They are formed at the junction of the
developmental lobes of the enamel.
 Sound coalescence of the lobes results in grooves,
faulty coalescence results in fissures.
 Deep enamel fissures acts as a niche for
acidogenic bacteria
- Easily penetrate the floor
- spreads along the DEJ
- undermining of enamel
79

80.  Surface of enamel in the cervical region should be kept
smooth & well polished.
- otherwise food debris & bacterial plaque
accumulate on the roughened surface.
80

81. Developmental Defects of Enamel
Hypoplasia
Hypocalcification
81

82. Hypoplasia
 Incomplete or defective formation of
enamel matrix
 These are the principal expressions
of pathologic amelogenesis
 Manifested as pitting, furrowing,
even total absence
82

83. Hypocalcification
 Maturation is lacking or
incomplete
 A deficiency of mineral
content is found
 Opaque or chalky white areas
on normally contoured enamel
surface
83

84. Systemic hypocalcification
 Major cause is the increased fluoride content of water
(>1.5 ppm).
 If the injury is during the maturation stage deficiency of
calcification will occur
84

85. Hereditary hypocalcification
 Normal amount of enamel produced,but
hypomineralized.
 It is soon discolored, abraded by mastication,
or peeled off in layers.
 Affected teeth may have areas of coronal
discoloration, or they may have actual pits and
irregularities
85

86. AMELOGENESIS IMPERFECTA
 It represents a group of hereditary defects that
cause disruption to the structure and clinical
appearance of enamel.
 It is entirely an ectodermal disturbance and
the mesodermal components of the tooth
are normal.
86

87.  According to the 3 stages in the development of normal
enamel, 3 basic types are recognized.
1.Hypoplastic type
 There is defective matrix formation.
 Enamel has not formed to full normal thickness on newly
erupted teeth
 The teeth are small and may be
white, yellow, or brown,
87

88.  Defective mineralization of formed matrix.
 The enamel may have a normal thickness, but it’s
too soft.
 The teeth may be white, yellow, or brown, and the
enamel may be rough.
88

89. 3. Hypo maturation type
 The teeth are opaque to yellow or brown with
sensitivity.
 The enamel has a normal thickness, but it’s too soft,
so the teeth appear mottled and may wear away and
break.
89

90. Caries and Enamel
 Is an irreversible microbial disease of the calcified tissue of
the teeth, characterized by demineralization of inorganic part
and destruction of organic substance of tooth,which often
leads to cavitation.
90

91. Clinical characteristics
 On clean dry tooth the earliest evidence of caries is a white spot
which are chalky white and opaque
 They are revealed only when the tooth surface is dry.
 The surface texture is unaltered and these areas of enamel lose
their translucency because of the extensive subsurface porosity
caused by demineralization.
91

92. Zones of enamel caries
 Zone1: translucent zone.
 Zone2: dark zone.
 Zone3: body of lesion.
 Zone4: surface zone
92

93. 1. Translucent zone
 Deepest zone
 Represent advancing front of lesion
 Pore volume is 1%
93

94. 2. Dark zone
 Lies adjacent and superficial to translucent
zone
 Does not transmit polarized light
 Total pore volume 2- 4%
94

95. 3. Body of the lesion
 Largest portion
 Area of gretest demineralization
 Pore volume 5 – 25 %
 Striae of retzius is more prominent
4. Surface zone
 Relatively stable layer and unaffected by caries
 Radiopacity similar to normal enamel
 Pore volume less than 5% of the spaces.
95

96. Non carious lesions of enamel
 Attrition
 Abrasion
 Erosion
 Localized nonhereditary enamel hypoplasia
 Localized non hereditary enamel hypocalcification
 Discoloration
 Amelogenesis imperfecta
96

97. Discoloration
 Can occur due to:
 Extrinsic factors:
1. Tobacco/tea stains
2. Poor oral hygiene
3. Food colors
4. Existing restorations
5. Chromogenic bacteria
97

98.  Intrinsic factors:
 1. Caries.
 2. Fluorosis.
 3. Tetracycline and other drugs.
 4. Age changes.
 5. Non vital teeth
 6. Internal resorption.
 7. Hereditary disorders.
98

99. Effects of fluoride on enamel
1.Anti cariogenic property
 Increased enamel resistance or reduction in enamel
solubility.
 Calcium hydroxy apatite  fluroapatite
99

100. 2.Increased rate of post eruptive maturation
3.Remineralisation of incipient lesion
4.Inhibition of demineralisation
5.Interference with microorganisms
6.Modification of tooth morphology
10
0

101. Flourosis
► Caused by excessive systemic flouride during enamel
matrix formation and calcification.
► Mild intermittent white spotting
► Chalky or opaque areas
► Surface pitting
► Marked wear of enamel surface
► Brown stains
► Severe cases-corroded appearance
10
1

102. Flourosis
10
2

103. Bleaching
 The lightening of the color of a tooth through the
application of a chemical agent to oxidize the
organic pigmentation of the tooth is referred to as
bleaching.
 Hydrogen peroxide is most commonly used.
10
3

104. Types of Bleaching
A) Non-Vital bleaching
 In-Office /Thermocatalytic technique
 Out of the office technique/Walking Bleach
B)Vital Bleaching
In Office technique /Power bleaching.
Dentist prescribed home applied technique (Night guard
vital bleaching)
10
4

105. Enamel Microabrasion
 It is not a bleaching technique.
 A selective erosion process that removes stained enamel.
 Currently microabrasion is recommended for the removal of
stains that are superficial and localized in enamel.
10
5

106.  Uses of 18% hydrochloric acid and pumice . Only one
commercially developed system currently exists for
enamel microabrasion.
 The PREMA system (Premier enamel micro abrasion)
10
6

107. ADHESION TO ENAMEL
ACID ETCHING
 Achieved through acid etching, which enlarges its surface
area for bonding.
 Buonocore in 1955.
 Underlying mechanism of the bond suggested that resin
tags were formed and micromechanically interlocked with
the enamel micro porosities created by etching
107

108.  As there are 30,000 to 40,000 enamel rods/sq mm
and the etch penetration increases the bondable
surface area 10 to 20 fold
 Etching transforms the smooth enamel surface into an
irregular surface with a high surface free energy
108

109.  Acid etching removes about 10µm of the enamel surface
and creates a micro porous layer from 5 to 50 µm deep.
 When doing etching for bonding composites
- Prismless enamel should not provide mechanical
retention
- So etching should go beyond to the prismatic enamel
109

110. GENERAL PRINCIPLES FOR
FORMULATION OF ENAMEL WALLS
 The enamel portion of a wall should be the
smoothest portion of the preparation anatomy.
 Junction between different enamel walls should be
rounded
-decreasing stress concentration there.
 Enamel walls should be well supported by dentin
110

111. cavosurface angle
 Amalgam restoration -90 degree (butt joint).
 Cast inlay -130-140 degree (lap joint)
 For Amalgam class 2 – bevelling the gingival
margin with GMT : 15-20 degree.
111

112. Effect of burs
 Higher speed results in more rougher surface
 Straight cut provides smoother finish than cross
cut design.
 Tungsten carbide provide smoother finish than
stainless or diamond burs.
112

113. Conclusion
 Much of the art of restorative dentistry comes from efforts
to simulate the color, texture, translucency and contours of
enamel with synthetic dental materials such as resin
composite or porcelain
 Lifelong preservation of the patient’s own enamel is one of
the defining goals of the dentist.
113

114. References
 Oral history - Ten Cate
 Orbans histology and embryology
 Operative dentistry - Clifford M. Sturdevant
 Operative dentistry - Marzouk.
 Philips’ science of dental materials- Anusavice
 Shafer’s Textbook of Oral Pathology
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