Cementoblastoma is defined as a neoplasm characterized by formation of sheets of cementum like tissue containing a large number of reversal lines and lack of mineralization at the periphery of the mass or in the more active growth area. Locally aggressive resulting in bony expansion, root resorption, displacement of adjacent teeth, and jaw deformity.

1. Mesenchymal origin tumors
a- Odontogenic fibroma
b- Odontogenic myxoma
c- Benign cementoblastoma

2. Odontogenic Fibroma
It is a benign neoplasm derived from
connective tissue of odontogenic origin, it
could arise intraosseously without
odontogenic epithelium (desmoplastic
fibroma) which is rare ,or extraosseously
(peripheral odontogenic fibroma) which is
relatively common.

3. Desmoplastic fibroma:-
Mostly affect the mandible of young adult.
Painless swelling lead to extensive bone
expansion of affected area.
Radiograph:- similar to ameloblastoma.
Histopathology:- acellular hyalinized connective
tissue in scar like pattern.
Treatment:- enucleation with high recurrence
rate.

4. Peripheral odontogenic fibroma:-
Derived from overlying gingival epithelium or
rest of dental lamina
Clinically:- focal growth of gingiva like
peripheral fibroma may be indistinguishable from
a fibrous epulis.
Histopathology:- a mixture of dense connective
tissue, (collagenized fibrous tissue) that separate
localized zones of myxomatous, & loose
connective tissue. Small islands of odontogenic
epithelium.

7. Odontogenic Myxoma
It is a special tumor for the jaws locally
aggressive arise from dental
mesenchymal tissue. It is infiltrative
(not capsulated) benign tumor.
Most commonly involve the mandible,
appear as a painless swelling or
asymptomatic

8. Clinically
It occurs in young age group, most commonly
involve the mandible, appear as a painless
swelling or asymptomatic. The maxillary lesion
will arise into the sinus while the mandibular
lesion found in molar, premolar area & often
extend into ramus.
Radiograph : resemble ameloblastoma.

10. Histopathology
- Grossly it is a gelatinous tissue,
microscopically consist of a scanty spindle
shape irregular cells with fine long
anastomosing processes, and a mucoid material
& few collagen fibers & epithelial rest. The
margins of the lesion are ill defined & the bone
trabeculae show resorption. Some cases contain
an odontogenic epithelium.

13. BENIGN CEMENTOBLASTOMA
growing in continuity with apical cemental
layer of molar & premolar, that produce
expansion of cortical plate & pain (which is
diagnostic feature of this tumor) which
become more intense if the area is palpated,
but the teeth are vital.

18. Mixed epithelial & mesenchymal
origin
a- Calcifying odontogenic cyst
b- Ameloblastic fibroma
c- Adenomatoid odontogenic
tumor
d- Odontoma

19. CALCIFYING ODONTOGENIC
CYST
It occurs at any age in both jaws, most commonly
in anterior region (anterior to the 1st molar).
Usually extraosseous lesion appear as focal
localized swelling in gingiva whereas
intraosseous lesion produce generalized
expansion of buccal & lingual cortical plates.

24. Adenomatoid Odontogenic
Tumor
occurs between (10-19 years) at early
adolescence more frequent in female at anterior
maxilla. It is derived from enamel organ
epithelium it is believed to be odontogenic
ectomesenchymal in origin. It is frequently
asymptomatic discovered by radiograph, large
lesion may produce painless swelling. (common
in maxilla).

29. It surrounded by thick capsule, the cutting surface
either cystic or solid. A well defined capsule
enclose either mass or strand of epithelium among
which microcystic & duct like structure, these
microcystic structures may contain homogenous
eosinophilic material. Fragments of amorphous
cementoid or dentinoid calcification may be seen
between the epithelium.

34. Odontoma
Odontomes are dental hamartomas
containing the calcified dental tissue.
Odontoma is a hamartomatous lesion found
over unerupted teeth containing enamel,
dentine, pulp and cementum in either
normal tooth shape (compound) or
abnormal tooth shape (complex).

35.  It represents nearly 70% of whole odontogenic
tumors.
 Complex odontoma is more commonly
occurred in posterior mandible than maxilla,
as asymptomatic swelling.
 Compound odontoma is more commonly
occurs in anterior maxilla than in mandible and
as a symptomatic swelling either over the
crowns of unerupted teeth or between the roots
of erupted one.

36. Complex Odontoma

43. Compound Odontoma

49. B- Malignant tumors
Malignant ameloblastoma
It is similar to histological features of
ameloblastoma, may give pulmonary metastasis
& retain microscopic appearance of primary
tumor result either from aspiration or
implantation.
Treatment: local excision.

50. Ameloblastic carcinoma
Histologically resembles ameloblastoma but
loss the differentiation & behave in malignant
way, it spreads by lymph node & distant to other
regions later on.
Microscopically resemble squamous cell
carcinoma & is treated as intraosseous carcinoma
(malignant tumor in jaw). The prognosis is poor
when lymph node is involved.