This document provides information on various odontogenic tumors including: - Ameloblastoma - A benign but locally aggressive tumor that can cause facial deformities. It has follicular and plexiform histological patterns. - Calcifying epithelial odontogenic tumor (CEOT) - A locally aggressive tumor consisting of epithelial strands and spheres often accompanied by calcifications. It can be central or peripheral. - Adenomatoid odontogenic tumor (AOT) - A non-aggressive lesion usually found around crowns of unerupted teeth consisting of epithelial swirls and ducts with calcifications. The document describes clinical features, radiographic appearances, histological patterns and characteristics of these

1. ODONTOGENIC
TUMORS
Sana Rasheed
ODONTOGENIC
TUMORS
Sana Rasheed
Akhtar Saeed Medical and Dental College, Lahore, Pakistan

3. EPITHELIAL ODONTOGENIC
TUMORS

4. AMELOBLASTOMA
A locally aggressive neoplasm of odontogenic epithelium
that has a wide spectrum of histologic patterns resembling
early odontogenesis.
• It is a benign neoplasm.
Four sources:
(1) remnants of the dental lamina (rests of Serres)
(2) reduced enamel epithelium
(3) rests of Malassez
(4) the basal cell layer of overlying surface epithelium

6. Common features:
• Slow growing
• Locally aggressive
• Capable of causing large facial deformities
• A high recurrence rate
• Metastasis is rare

7. Common Ameloblastoma CONVENTIONAL SOLID OR MULTICYSTIC INTRAOSSEOUS
AMELOBLASTOMA
Oth er n ames : simp le or follic u lar amelob lastoma
• occur in patients over 25 years of age
• third to seventh decades of life (25+ to 60s)
CLINICAL FEATURES
1. May produce extensive, even grotesque, deformities of the mandible and maxilla.
2. Often asymptomatic , painless, bony expansion.
3. Painless and no paresthesia.
4. It is most commonly located in the mandible, with 75% occurring in the molar and ascending
ramus areas.
5. Lesions of the maxilla are located in the molar area and may extend to the maxillary sinus and
floor of the nose.
6. Age: patients between 20 to 40 years of age.
7. No significant sex or race predilection exists.

9. Tendency to expand the bony cortices.
Thinned outer shell of bone cracks easily when palpated—a
diagnostic sign referred to as “eggshell cracking.”
RADIOGRAPHIC FEATURES
Multilocular lesions are described as having a “soap bubble”
appearance (when the radiolucent loculations are large) or as being
“honeycombed” (when the loculations are small)

12. The desmoplastic ameloblastoma has
a marked predilection to occur in the anterior regions
of
the jaws, with equal distribution between the
mandible and
the maxilla.
Buccal and lingual cortical expansion
Resorption of the roots of teeth adjacent
to the tumor

14. HISTOPATHOLOGY
1. Reverse polarization in basal cell layer in
the epithelium
2. The cytoplasm adjacent to the basement
membrane assumes a clear zone.
3. DD: calcifying odontogenic cysts and
odontogenic keratocysts.
4. Specific architectural patterns of
epithelium: two most common are the
follicular and plexiform patterns

16. The follicular pattern
1. Most prevalent
2. It consists of epithelium in the form of islands, strands, and
medullary arrangements.
3. Background stroma of fibrous connective tissue.
4. The epithelial arrangements:
• Outer border : the palisaded ameloblast-like cells in which
reversed polarization has occurred.
• Inside: loosely arranged and widely separated triangular-
shaped cells that are similar to those of the stellate reticulum.
5. A distinctive zone of hyalinization surrounds the epithelial
islands

22. Acanthomatous pattern: the central cells are transformed to squamous cells that produce keratin within
individual cells or in the form of keratin pearls.
Granular cell variant: The central cells appear swollen and densely packed with eosinophilic granules

26. Basal cell variant
1. Only densely packed, large proliferating cuboidal-shaped basaloid cells exist in narrow strands
2. Without stellate reticulum or other forms of centrally located epithelial cells

27. Desmoplastic ameloblastoma
1. The epithelial islands and strands are
small and have cuboidal and darkly
stained cells.
2. The epithelial component is widely
separated by fibrous tissue that is
dense and scarlike.
3. Small islands and cords of odontogenic
epithelium in a densely collagenized
stroma.
4. A particular predilection for
penetrating the surrounding
trabecular bone and remaining
undetected. (metaplastic potential)

29. Desmoplastic ameloblastoma
• This variant has a mixed radiolucent and radiopaque radiographic
appearance that resembles a fibro-osseous lesion.
Why is it more difficult to treat?
• It appears to have a particular predilection for penetrating the
surrounding trabecular bone and remaining undetected.
• Consequently, finding the exact interface of the lesion with normal
bone is especially difficult during surgical management.

30. The plexiform pattern
1. Epithelium in a fishnet or mesh
arrangement with columnar or cuboidal
ameloblast-like cells
2. No reversed polarization of the nucleus in
basal cells.
3. General pattern: thin anastomosing strands
of odontogenic epithelium.
4. Large and small cystlike areas are present in
the connective tissue (as compared to
epithelial islands in follicular pattern).

35. Unicystic Ameloblastoma
CLINICAL FEATURES
1. Age: 16 to 20 years of age
2. The unicystic ameloblastoma
occurs in a dentigerous cyst
relationship
3. Usually associated with a
severely displaced third
molar.
4. Mandible > Maxilla.
RADIOGRAPHIC FEATURES
1. Unilocular lesions
2. Well demarcated
3. Corticated.
4. A tooth is often present within the
radiolucency.
5. Root displacement in premolar area.

37. HISTOPATHOLOGY
1. Fibrous connective tissue
capsule.
2. A solitary large fluid-filled
lumen.
3. The epithelial lining of the
lumen :
• Pallisaded basal cells
• Hyperchromatic
• Reverse polarization of
nucleus
4. The remaining layers
resemble stellate reticulum.
Intraluminal
unicystic
ameloblastoma
Epithelium is
thickened in
some areas with
papillary
projections
extending into
the lumen.
Mural unicystic
ameloblastoma
When the thickened
lining penetrates the
adjacent capsule.
Plexiform
unicystic ameloblastoma
Intraluminal nodular
projections that contain a
network or mesh pattern of
epithelium.

40. Peripheral Ameloblastoma
1. Limited to the soft tissues of the
gingiva.
2. Arises directly from the
overlying epithelium or from the
remnants of the dental lamina
located in the extraosseous soft
tissue.
DDs:
• odontogenic hamartoma
• peripheral odontogenic fibroma

41. CLINICAL FEATURES
1. Age: 23 to 82 years of age
2. Mandible > Maxilla
3. Appear as firm sessile nodules of the gingiva
4. Size : 0.5 to 2.0 cm.
5. They have a smooth surface and normal coloration.
6. May be erythematous or ulcerated.
RADIOGRAPHIC FEATURES
• Lesions are primarily extraosseous.
• A superficial saucerization of the cortical plate that
appears as a cup-shaped radiolucency beneath the
elevated nodule as the result of the pressure the lesion
exerts on the bone.
• Tooth separation.

42. HISTOPATHOLOGY
1. Islands and strands of odontogenic
epithelium.
2. Acanthomatous pattern common:
central areas of keratin formation
or the cystic pattern.
3. The epithelial islands and strands
are usually surrounded by fibrous
tissue.
4. A cup-shaped resorption of the
cortical plate.

44. CALCIFYING EPITHELIAL
ODONTOGENIC TUMOR
• A locally aggressive tumor
consisting of strands and
medullary patterns of
squamous and clear cells
that are often
accompanied by spherical
calcifications and amyloid-
staining hyaline deposits.

45. CALCIFYING EPITHELIAL
ODONTOGENIC TUMOR
1. Other name : “Pindborg tumor.”
2. Locally aggressive
3. Origin: It is thought to originate from the epithelial rests of the dental lamina or from the
reduced enamel epithelium that overlies the crowns of the teeth
4. it usually contains spherical and diffuse calcifications within the epithelial islands and the
connective tissue stroma.
5. CEOT occurs as either a central (intraosseous) or peripheral (extraosseous) lesion

47. CALCIFYING EPITHELIAL
ODONTOGENIC TUMOR
• CLINICAL FEATURES
Peripheral CEOT most commonly occurs in the anterior part of the mouth. It presents
as a superficial soft tissue swelling of the gingiva in tooth-bearing and edentulous
areas of the jaws
Nasal airway obstruction, epistaxis, and proptosis are
sometimes experienced in the maxilla.
ages of 20 and 60
years
2/3rd in the mandible.
Molar area most
frequently, then
premolar.
slowly enlarging,
painless mass

48. CALCIFYING EPITHELIAL
ODONTOGENIC TUMOR
• RADIOGRAPHIC FEATURES
• A diffuse radiolucency with faint flecks of calcified structures.

49. CALCIFYING EPITHELIAL
ODONTOGENIC TUMOR
1. A mixture of radiolucent and radiopaque areas.
2. The radiopaque areas can be diffuse and faint or discrete, round structures.
3. Intraosseous lesions may occur over teeth that are unerupted, displaced, or
both.
4. Small lesions are often unilocular radiolucencies.
5. Lesions have indistinct lines of demarcation with the surrounding bone.

51. CALCIFYING EPITHELIAL
ODONTOGENIC TUMOR
Because CEOT usually occurs over unerupted teeth and may be a
radiolucent or mixed unilocular lesion, the radiographic differential
diagnosis of CEOT includes
• dentigerous cyst
• adenomatoid odontogenic tumor
• ameloblastic fibro-odontoma
The peripheral lesions are commonly radiolucent. Sometimes
lesions exhibit superficial cortical erosion.

52. HISTOPATHOLOGY
1. Sheets of polyhedral cells with prominent intercellular
bridges.
2. Stains positive with Congo red stain and thioflavine T,
shows positivity for
1. * amyloid deposits (it give apple green bifringence)
2. it can also be positive for
3. *tissue degeneration, *type IV collagen and *basal lamina,
*enamel matrix, or *keratin
3. Multiple concentric Liesegang ring calcifications seen.
4. The cells may exhibit
• pleomorphism
• multinucleation
• prominent nucleoli
• hyperchromatism

55. • Pools of homogeneous eosinophilic
material are often found within and
between the sheets of epithelial cells
• Scattered spherical calcifications.
• When clear cells dominate the
epithelial component, the lesion is
referred to as clear cell variant of
CEOT.

59. ADENOMATOID ODONTOGENIC TUMOR
• Clinical location around the
crown of a tooth
• Lesion probably originates
from the reduced enamel
epithelium.
• Lesion is biologically
nonaggressive and requires
conservative treatment
A wellcircumscribed lesion
derived from odontogenic
epithelium
that usually occurs around
the crowns of unerupted
anterior teeth of young
patients and consists of
epithelium in swirls and
ductal patterns interspersed
with spherical calcifications.

61. CLINICAL FEATURES
1. The AOT is usually associated with an
impacted tooth and is often a cause of
failure of the tooth to erupt.
2. Age: the second decade of life, 14 to 15
years of age.
3. Gender: Females > Men
4. Location: Anterior mouth, usually
around an impacted cuspid.
5. Appearance: An area of swelling over
an unerupted tooth.
DD:
1. dentigerous cyst
2. unicystic ameloblastoma, CEOT
3. calcifying odontogenic cyst

62. RADIOGRAPHIC FEATURES
1. A unilocular lesion with well-corticated
borders that contains a tooth.
2. Radiolucent lesions, but some contain
faint flecks of radiopacities.
3. Lesions often surround the crown of an
impacted tooth, as they do in a
dentigerous cyst.
4. However, close examination reveals that
AOT differs from a dentigerous cyst,
because the radiolucency usually extends
apically beyond the cemento-enamel
junction.

64. HISTOPATHOLOGY
1. Outer capsule of fibrous connective tissue
2. A nodular pattern of epithelial cells.
3. Solid or contain focal cystic areas.
4. The nodules are composed of spindled epithelial cells that are often in a swirled pattern.
5. Distinctive feature of AOT : Ductal epithelial structures composed of a circular
arrangement of columnar cells with periodic acid-Schiff (PAS)-positive eosinophilic
material. Hyaline rings.
6. Spherical calcifications
7. Diffuse areas of hyaline material in the stroma

69. CALCIFYING ODONTOGENIC CYST (Gorlin cyst)
A rare, wellcircumscribed, solid or
cystic lesion derived from
odontogenic epithelium that
microscopically resembles
ameloblastoma but differs by
containing ghost cells and spherical
calcifications.
Also called odontogenic ghost cell tumor

70. CLINICAL FEATURES
Extraosseous lesions appear as focal localized swellings, whereas intraosseous
lesions produce a generalized expansion of the buccal and lingual cortices.
Pain is usually absent.
It can occur in any part
of the toothbearing
areas of the mouth
more common in the
areas anterior to the
first molar.
extraosseous or
intraosseous location
predilection for
patients in the second
decade

72. RADIOGRAPHIC FEATURES
• Well-circumscribed
• Unilocular radiolucencies
• Flecks of indistinct
radiopacities.
• In some lesions the flecks and
small nodular radiopacities are
confined to the periphery, with
larger toothlike structures more
centrally located

75. HISTOPATHOLOGY
• Some lesions have a cystic center, and
others are solid.
• The epithelial component consists of an
outer layer of palisaded columnar basal
cells and an inner layer of stellate
reticulum like cells.
Greatly enlarged eosinophilic
epithelial cells without
visible nuclei, referred to as
ghost cells, are present
within
the stellate reticulum-like
areas.
Multiple spherical and
diffuse calcifications within the
epithelium and connective
tissue are also included

81. SQUAMOUS ODONTOGENIC TUMOR
• A rare, sometimes multifocal, potentially
aggressive lesion derived from
odontogenic epithelium and consisting of
islands of stratified squamous epithelium
that commonly contain microcysts and
calcifications in a dense fibrous
background.

82. SQUAMOUS ODONTOGENIC TUMOR

83. SQUAMOUS ODONTOGENIC TUMOR
SOT may originate from the remnants of the dental lamina, rests of
Malassez, or overlying epithelium

84. CLINICAL FEATURES
Lesion first detected as either a painless swelling or as
looseness of teeth in a region
occur anterior to the molars and are
equally distributed between the
mandible and maxilla
peak incidence in the third decade
Initially the lesions
are slow growing

85. RADIOGRAPHIC FEATURES
• Resorption of roots is usually absent. Tooth separation is
common with smaller
lesions when they are
located in the bone that is
coronal to the root apices.Large ones are multilocular and have an
indistinct border.
Small lesions appear as unilocular
radiolucencies.

86. HISTOPATHOLOGY
Rounded and
elongated
islands of
relatively
normal-
appearing
stratified
squamous
epithelium
against a
cellular
fibrous
connective
tissue
The epithelial
islands vary in
size and have a
basal cell
layer of
inactive-
appearing
cuboidal cells.
The remainder of the
islands is composed of
matured intermediate
cells with prominent
desmosomal bridges.
Many of the
epithelial
islands have
central areas
of microcyst
formation,
whereas others
contain
spherical or
irregularly
shaped
calcified
structures.
Similar

87. CONNECTIVE TISSUE
ODONTOGENIC TUMORS

88. ODONTOGENIC FIBROMA
A peripheral or intraosseous
(central) benign neoplasm derived
from connective tissue
of odontogenic origin containing
widely scattered islands
and strands of embryonic
odontogenic epithelium and
calcifications.

89. Peripheral Odontogenic Fibroma

90. 1. The peripheral odontogenic fibroma is the
most common form of odontogenic fibroma
and appears to be derived from the
overlying gingival epithelium or the rests of
the dental lamina remaining in an
extraosseous location
2. DDs: gingival hamartoma or a peripheral
ameloblastoma

91. • Appearance as a
focal growth.
• It may be of normal
coloration or
erythematous when
ulceration occurs.
• Interdental lesions
often cause tooth
separation.
• When lesions contain
numerous
calcifications within
the cellular connective
tissue, some small
radiopaque flecks may
be visible.
• saucerization of the
cortical bone
• some widening of the
cervical portion of the
periodontal space.
• Dense connective
tissue that separates
localized zones of
myxomatous or loose
connective tissue.
• Small epithelial islands
• Irregularly shaped
hyalinized deposits
• The epithelial islands
will often contain clear
cells.
CLINICAL FEATURES RADIOGRAPHIC FEATURES HISTOPATHOLOGY

93. Central Odontogenic Fibroma
CLINICAL
FEATURES
Asymptomatic
Painless swelling
Located in
mandible.
RADIOGRAPHIC
FEATURES
• Unilocular
radiolucency
• Well circumscribed in
some and multilocular
in others.
• Some faint radiopaque
flecks
HISTOPATHOLOGY
• a cellular connective tissue
that contains widely scattered
thin strands of odontogenic
epithelium.
• The epithelial component
closely resembles dental
lamina and often contains cells
with clear cytoplasm.
• Spherical and diffuse
calcifications

95. ODONTOGENIC MYXOMA
An aggressive
intraosseous lesion
derived from
odontogenic connective
tissue and primarily
consisting of a mucoid
ground substance with
widely scattered
undifferentiated spindled
mesenchymal cells.
CLINICAL FEATURES
• Mandible = Maxilla
• Maxillary lesions erode into the sinus, often
crossing the midline and into the opposing sinus
cavity.
• Mandibular lesions are most commonly found in
the molar and premolar areas and often extend
into the ramus.
• Painless, slowly enlarging swellings.
• Displacement of teeth

96. RADIOGRAPHIC FEATURES
1. A multilocular radiolucency with a “soap bubble” or “honeycomb” pattern.
2. Faint residual fragments of trabecular bone
3. Expansion of cortical plates
4. Some tooth displacement occurs.

97. HISTOPATHOLOGY
1. Widely separated spindle- or angular shaped
cells against a background of a mucoid,
nonfibrillar ground substance.
2. In some odontogenic myxomas, focal areas of
fine strands of collagen and blood vessels
exhibiting a thin outer zone of hyalinization are
found.
3. Islands of residual bone in the periphery.
4. Islands of odontogenic epithelium and focal
calcifications.
5. Large amounts of a mature cellular fibrous
tissue. These lesions are referred to as
myxofibroma.

98. CEMENTOBLASTOMA
A benign, well-
circumscribed neoplasm of
cementum-like tissue
growing in continuity with
the apical cemental layer
of a molar or premolar
that produces expansion of
cortical plates and pain.
CLINICAL FEATURES
• Second and third decades of life
• Molar and premolar area, with lesions attached to the apical third of
one of the roots.
• True neoplasms
• Buccal and lingual cortical plate expansion.
• Pain is produced.
• The teeth usually remain vital.
RADIOGRAPHIC FEATURES
• Lesions are unilocular and well demarcated.
• They may be completely radiolucent, a mixture of radiolucent and radiopaque, or completely
radiopaque.
• Root resorption seen.

99. HISTOPATHOLOGY
1. Unmineralized eosinophilic matrix rimmed by
plump cementoblasts.
2. Acellular peripheral zone
3. The Cellular central zone :
• mineralized tissue
• multinucleated cells
• increased number of reversal lines (due to
remodeling)

102. MIXED ODONTOGENIC
TUMORS

103. AMELOBLASTIC FIBROMA
A circumscribed lesion predominantly located
over unerupted molars in young patients; the
epithelium and connective tissue recapitulate
the cap and bell stages of odontogenesis.
CLINICAL FEATURES
1. Young patients with an average age of 14
years.
2. It is slow growing
3. Mandibular molar area, often over an
unerupted tooth.
4. Slight buccal and lingual cortical expansion.
RADIOGRAPHIC FEATURES
Lesions are most often over
an unerupted tooth.
They are unilocular or
multilocular radiolucencies.
They are well corticated and
vary considerably in size.

105. HISTOPATHOLOGY
1. Thin strands and cords of
odontogenic epithelium that
resembles the dental lamina.
2. The background is composed of
embryonic connective tissue
containing fibroblasts.
3. Zones of hyalinization, sometimes
with associated focal areas of
calcification, are often found
surrounding the epithelial
component of the lesion

106. ODONTOMA
• Odontomas are composed of mature enamel, dentin, and pulp
• May be compound or complex.
• Because most occur during the period of normal tooth development
and often reach a fixed size, they are not considered true neoplasms,
but hamartomas.
A usually hamartomatous lesion commonly
found over unerupted teeth and containing enamel, dentin,
pulp, and cementum in either recognizable tooth shapes
(compound) or a solid, gnarled mass (complex).

108. CLINICAL FEATURES
• 70% of all
odontogenic tumors.
• First and second
decades
• Maxilla > Mandible
• Tooth fails to erupt at
its scheduled time
• Asymptomatic
swelling around the
tooth.

110. RADIOGRAPHIC FEATURES
• Compound odontomas are usually
located in the anterior part of the mouth,
either over the crowns of unerupted
teeth or between the roots of erupted
ones.
• Lesions are usually unilocular, containing
multiple radiopaque structures that
resemble miniature teeth.
• Compound odontomas may contain as
few as 2 to 3 miniature toothlike
structures or as many as 20 to 30.
A complex odontoma is most commonly found
in the posterior parts of the mandible over
impacted teeth and can attain sizes up to
several centimeters.
They appear as a solid radiopaque mass
exhibiting some nodularity and are surrounded
by a thin, radiolucent zone.
The lesions are unilocular and separated
from normal bone by a distinct line of
cortication. Individual toothlike structures are
absent.

114. HISTOPATHOLOGY
The enamel, dentin, and pulpal
tissue of the toothlike
structures of compound
odontoma are arranged in an
orderly pattern.
Within the surrounding
capsule, a thin band of
follicular connective tissue
separates each miniature
conical tooth.
Complex odontoma differs by being composed of
a single, gnarled, disorganized mass of enamel,
dentin, and pulp, with no recognizable tooth
shapes.
Both compound and complex
forms may also contain reduced enamel
epithelium, secretory ameloblasts, and functional
odontoblasts.
Islands of odontogenic rests and spherical
calcifications are common in the surrounding
connective tissue.

118. AMELOBLASTIC FIBRO-ODONTOMA
An expansile growth in young
patients that contains the soft
tissue components of
ameloblastic fibroma and the
hard tissue components of
complex odontoma.

119. CLINICAL FEATURES
• First and second
decades
• It is primarily
located in the
posterior areas of
the mandible
• It appears as a
slowly developing
swelling of the
affected portion of
the jaw, usually in
the area of an
unerupted tooth.
RADIOGRAPHIC
FEATURES
• Unilocular, well-
circumscribed, mixed
radiolucent and radiopaque
lesion.
• The opacities are usually
diffuse and nodular.
• Most lesions also contain an
impacted tooth.

120. HISTOPATHOLOGY
• Areas consist of strands and cords of epithelium that resemble dental lamina
• Background of embryonic connective tissue composed of randomly oriented fibroblasts.
• In adjacent areas, both mature and immature forms of complex odontoma can be found.
• The lesion may be slightly lobular but is always surrounded by a well-formed capsule.

122. MALIGNANT
ODONTOGENIC
TUMORS

123. MALIGNANT AMELOBLASTOMA
• Ameloblastomas in which metastasis
has occurred to regional lymph nodes
or to other distant sites, the lungs
being most common.
• Recurrance occurs.
A lesion with the
histopathologic features of
common ameloblastoma in
which documented
metastasis has occurred.

124. AMELOBLASTIC CARCINOMA
An aggressive neoplasm
of the mandible or maxilla in which the
epithelial component
exhibits features of ameloblastoma but
with notable cytologic malignancy.
The ameloblastic carcinoma differs
from malignant ameloblastoma in
that portions of its epithelial
component are composed of
cytologically malignant cells, yet
the lesion is still readily recognizable
as ameloblastoma

125. The ameloblastic carcinoma differs
from malignant ameloblastoma in
that portions of its epithelial
component are composed of
cytologically malignant cells, yet
the lesion is still readily recognizable
as ameloblastoma

126. ODONTOGENIC CARCINOMA
• The radiographic appearance exhibits a
diffuse “honeycomb” radiolucency, a
feature that is consistent with an aggressive
destructive intraosseous lesion.
• Islands and strands of clear cells present.
• The epithelial structures are usually
surrounded by zones of myxomatous
connective tissue.
An aggressive and
destructive intraosseous
lesion of the mandible or
maxilla that consists of
poorly differentiated
epithelial cells and
clear cells in a pattern that
is reminiscent of early
odontogenesis.
The usual features of malignancy,
such as high mitotic index, hyperchromatism,
and pleomorphism, are not usually found in
these lesions.
Odontogenic carcinoma
is difficult to cure because it is very infiltrative and has
a high rate of recurrence.

130. Honey comb or Soap bubble appearance
• Common Ameloblastoma
• Odontogenic myxoma
• Odontogenic carcinoma (honeycomb)

131. References
• Contemporary Oral and Maxillofacial Pathology - 2nd Edition
• Neville Oral and Maxillofacial Pathology
• Hack Dentistry – Youtube
• www.pathpedia.com