1. Odontogenic Tumors

11. Classification of Odontogenic Tumors*
I. Tumors of odontogenic epithelium
A. Ameloblastoma
1. Malignant ameloblastoma
2. Ameloblastic carcinoma
B. Clear cell odontogenic carcinoma
C. Adenomatoid odontogenic tumor
D. Calcifying epithelial odontogenic tumor
E. Squamous odontogenic tumor
II. Mixed odontogenic tumors
A. Ameloblastic fibroma
B. Ameloblastic fibro-odontoma
C. Ameloblastic fibrosarcoma
D. Odontoameloblastoma
E. Compound odontoma
F. Complex odontoma
III. Tumors of odontogenic ectomesenchyme
A. Odontogenic fibroma
B. Granular cell odontogenic tumor
C. Odontogenic myxoma
D. Cementoblastoma
* From Neville, et al.

12. BENIGN, NO RECURRENCE POTENTIAL Adenomatoid odontogenic tumor
Squamous odontogenic tumor
Cementoblastoma
Periapical cementoosseous dysplasia
Odontoma
BENIGN, SOME RECURRENCE POTENTIAL
Cystic ameloblastoma (unicystic)
Calcifying epithelial odontogenic tumor
Central odontogenic fibroma
Florid cementoosseous dysplasia
Ameloblastic fibroma and fibroodontoma
*From Regezi, et al.
Biologic Classification of Odontogenic Tumors*
BENIGN, AGGRESSIVE
Ameloblastoma
Clear cell odontogenic tumor (some consider this a carcinoma)
Odontogenic ghost cell tumor (COC, solid type)
Odontogenic myxoma
Odontoameloblastoma
MALIGNANT
Malignant ameloblastoma
Ameloblastic carcinoma
Primary intraosseous carcinoma
Odontogenic ghost cell carcinoma
Ameloblastic fibrosarcoma

13. Tumors of Odontogenic Epithelium

14. Ameloblastoma
The ameloblastoma is the most common clinically significant (not the most common) odontogenic tumor.
It may develop from cell rests of the enamel organ; from the developing enamel organ; from the lining of odontogenic cysts or from the basal cells of the oral mucosa.

15. Ameloblastoma
It is typically slow-growing, locally invasive and runs a benign course.
H.G.B. Robinson described it as being a benign tumor that is “usually unicentric, non-functional, intermittent in growth, anatomically benign and clinically persistent.”

16. Ameloblastoma
Ameloblastomas occur in 3 different clinico-radiographic situations requiring different therapeutic considerations and having different prognoses.
Conventional Solid/Multicystic (86 % of all cases)
Unicystic (13 % of all cases)
Peripheral or Extraosseous (1 % of all cases)

17. Solid or Multicystic Ameloblastoma: Clinical Features
Patient Age: Approximately equal frequency from the third through the seventh decades.
Sex Predilection: Approximately equal.
Location: 80 % in mandible; 70 % in posterior regions.
Radiographic Appearance: Radiolucent lesion which is usually well-circumscribed; it may be unilocular or multilocular (soap-bubble, honeycomb); occasionally an ameloblastoma will be ill-defined with a ragged border.

18. Solid or Multicystic Ameloblastoma: Histologic Features
There are several microscopic subtypes but these generally have little bearing on the behavior of the tumor.
The follicular and plexiform types are the most common.
The follicular type is composed of islands of epithelium which resemble the enamel organ in a mature fibrous connective tissue stoma.

19. Solid or Multicystic Ameloblastoma: Histologic Features
The plexiform type is composed of long, anastomosing cords or larger sheets of odontogenic epithelium. Its stroma tends to be loose and more vascular.
The acanthomatous type shows evidence of extensive squamous metaplasia with keratin formation in the island of odontogenic epithelium.

20. Solid or Multicystic Ameloblastoma: Histologic Features
In the granular cell type there is transformation of groups of epithelial cells to granular cells; the nature of the granular change is unknown. This type is more common in young patients and has been shown to be clinically aggressive.

21. Solid or Multicystic Ameloblastoma: Histologic Features
The desmoplastic form is composed of islands/cords of odontogenic epithelium in a very dense collagenous stroma. It has a predilection for the anterior maxilla and because of the dense connective tissue may appear as a radiolucent-radiopaque lesion.
The basaloid type is the least common and is composed of uniform basaloid cells with no stellate reticulum.

22. Solid or Multicystic Ameloblastoma: Additional Features
In some studies solid/multicystic ameloblastomas are reported to be more common in Blacks.
While lesions are generally asymptomatic, ameloblastomas may cause paresthesia, pain particularly if infected and they can erode the cortical palates.

23. Solid or Multicystic Ameloblastoma: Treatment
Treatments have ranged from simple enucleation and curettage to en bloc resection.
Marginal resection is the most widely used method of treatment with the least recurrences reported (up to 15 %).
Most surgeons advocate a margin of at least 1.0 cm beyond the radiographic limits of the tumor as the tumor often extends beyond the apparent radiologic/clinical margins.

24. Solid or Multicystic Ameloblastoma: Prognosis
Treatment with curettage has resulted in recurrence rates ranging from %.
Treatment with marginal resection has resulted in approximately a 15 % recurrence rate.
Ameloblastomas of this type arising in the maxilla are particularly dangerous as it is often difficult in getting adequate margins.
Rarely is an ameloblastoma life threatening.

40. Unicystic Ameloblastoma: Clinical Features
Patient Age: The patients are younger than those with the solid/multicystic form. 50% are diagnosed during the second decade of life.
Sex Predilection: ? Same as for the solid??
Location: 90 % occur in the mandible usually in the posterior region.
Radiographic Appearance: Typically appears as a RL around the crown of an unerupted tooth (most commonly a mandibular third molar).

41. Unicystic Ameloblastoma: Histologic Features
Three histopathologic variants are recognized:
Luminal: the tumor is confined to the luminal surface of the cyst.
Intraluminal/plexiform: the tumor projects from the cystic lining; sometimes resembles the plexiform type of solid/multicystic ameloblastoma.
Mural: the tumor infiltrates the fibrous cystic wall.

42. Unicystic Ameloblastoma: Treatment and Prognosis
Enucleation of the cyst is probably adequate for the luminal and intraluminal/plexiform types.
Treatment of the mural type is controversial with some surgeons believing that local resection is best.
10-20 % recurrence after enucleation and curettage with all unicystic ameloblastomas.

48. Peripheral Ameloblastoma
These tumors are extraosseous and therefore occupy the lamina propria underneath the surface epithelium but outside of the bone.
Histologically, these lesions have the same features as the intraosseous forms of the tumor.

49. Peripheral Ameloblastoma: Clinical Features
Patient Age: Wide age range but most occur during middle-age.
Gender Predilection: This is not known.
Location: Posterior gingival/alveolar mucosa is involved most frequently. There is a slight predilection for the mandible. The buccal mucosa has been the site in a few reported cases.

50. Peripheral Ameloblastoma: Radiographic & Histologic Features
Radiographic Appearance: Although not in bone, a few cases have shown superficial erosion of the alvelolar bone.
Histologic Appearance: Islands of ameloblastic epithelium are observed in the lamina propria; plexiform and follicular patterns are the most common; in 50 % of the cases the tumor connects with the basal cell layer of the surface epithelium.

51. Peripheral Ameloblastoma: Treatment and Prognosis
Unlike its intraosseous counterpart, this tumor has an innocuous clinical behavior.
Patients respond well to local surgical excision.
Some reports indicate a 25 % recurrence rate but in these cases as second surgical procedure results in cure.
There has been a rare malignant change reported.

53. Malignant Ameloblastoma and Ameloblastic Carcinoma
Less than 1 % of the ameloblastomas show malignant behavior with the development of metastases.
Malignant ameloblastoma is a tumor that shows histologic features of the typical (benign) ameloblastoma in both the primary and secondary deposits.
Ameloblastic carcinoma is a tumor that shows cytologic features of malignancy in the primary tumor, in recurrence and any metastases.

54. Malignant Ameloblastoma & Ameloblastic Carcinoma: Clinical
Patients range in age from 4-75 with a mean of 30 years.
Metastasis has occurred from 1-30 years after the initial treatment.
Metastases most often occur in the lungs and in the case of malignant ameloblastoma raises the question of aspiration during surgery. Spread has also occurred to the cervical lymph nodes and to vertebrae and viscera.

55. Malignant Ameloblastoma & Ameloblastic Carcinoma: X-Ray
With the malignant ameloblastoma, the appearance is similar to the typical solid/multicystic ameloblastoma.
The ameloblastic carcinoma is often more aggressive with the lesion appearing as an ill-defined radiolucency with cortical destruction.

56. Malignant Ameloblastoma & Ameloblastic Carcinoma: Histology
With the malignant ameloblastoma, both the primary and metastases show no microscopic features that differ from those of the typical solid/multicystic ameloblastoma.
The ameloblastic carcinoma shows cytological features of malignancy in addition to a pattern of an ameloblastoma.

57. Malignant Ameloblastoma & Ameloblastic Carcinoma: Treatment & Prognosis
Long-term follow-up does not permit accurate assumptions to be made but prognosis appears to be poor.
Approximately 50 % of the patients with documented metastases and long-term follow-up have died as the result of their disease.

60. Clear Cell Odontogenic Carcinoma
Clear Cell Odontogenic Tumor

61. Clear Cell Odontogenic Carcinoma
First reported in 1985 with few cases thus far.
Tumor appears to be of odontogenic origin but its histogenesis is uncertain.
The term carcinoma is used because most cases have demonstrated aggressive behavior with invasion of contiguous structures.

62. Clear Cell Odontogenic Carcinoma: Clinical and Radiographic Features
Patient Age: Patients are usually over 50 year old.
Gender Predilection: Most cases have occurred in females but because of the small number of reports thus far the question validity is raised.
Location: Lesions have occurred in both jaws.
Radiographic Features: Usually a unilocular or multilocular radiolucency with the margins being poorly defined or irregular.

63. Clear Cell Odontogenic Carcinoma: Histologic Features
Several patterns have occurred with the predominant pattern consisting of nests of epithelial cells with a clear or faintly eosinophilic cytoplasm separated by strands of hyalinized connective tissue.

64. Clear Cell Odontogenic Carcinoma: Histologic Features
The clear cells contain small amounts of glycogen.
The pathologist must rule out the other “clear cell tumors” such as a clear cell mucoepidermoid carcinoma, clear cell CEOT and metastatic renal cell carcinoma.

65. Clear Cell Odontogenic Carcinoma: Treatment and Prognosis
Most patients require fairly radical surgery as most authorities consider the tumor to be malignant.
Metastases to the regional lymph nodes and lungs have been reported.
There are too few cases to draw any conclusions about the prognosis of this tumor.

68. Adenomatoid Odontogenic Tumor (AOT)
Formerly called an adenoameloblastoma, a somewhat deceptive term that should be discarded, the AOT represents about 3-7 % of all odontogenic tumors.
This epithelial tumor has an inductive effect on the odontogenic ectomesenchyme with dentinoid frequently being produced.

69. AOT: Clinical Features
Patient Age: The peak age is in the second decade with a mean around 17 years.
Gender Predilection: Females, 2:1.
Location: Sixty-five percent of the AOTs occur in the maxilla with 65 % occurring in the canine region. Seventy-five percent of the cases are associated with the crown of an unerupted tooth. On rare occasion the lesion is extraosseous.

70. AOT: Radiographic and Additional Features
AOTs typically appear as pericoronal radiolucencies, which may have radiopaque material (“snowflake” calcifications) within the lucency.
These lesions are frequently asymptomatic and therefore are discovered upon routine radiographic examination. AOTs may also block the eruption of a permanent tooth and be discovered when radiographs are taken to “search for” the unerupted tooth.

71. AOT: Histologic Features
The lesion is usually surrounded by a thick, fibrous capsule.
The tumor is composed of spindle-shaped epithelial cells that form sheets, strands or whorled masses with little connective tissue.
The epithelial cells may form rosette-like structures, tubular or duct-like structures may be prominent or absent.
Calcifications may be observed in the tumor mass.

72. AOT: Treatment and Prognosis
Enucleation is the treatment of choice as the tumor is easily removed from the bone.
AOTs seldom recur.

83. Calcifying Epithelial Odontogenic Tumor (CEOT; Pindborg Tumor)
Pindborg tumor accounts for < 1 % of all odontogenic tumors.
It is clearly of odontogenic origin but its histogenesis is uncertain.
The tumor cells are said to resemble cells of the stratum intermedium.

84. CEOT: Clinical Features
Patient Age: Patients ages range from the second to the tenth decades with a mean around 40 years.
Gender Predilection: There is no reported sex predilection.
Location: 75 % of the CEOTs occur in the mandible with most occurring in the posterior region. A rare peripheral CEOT does occur.

85. CEOT: Radiographic Features
CEOTs occur as radiolucent lesions with/without opaque foci.
They are usually well-circumscribed and may be unilocular or multilocular.
Slightly over 50 % of the CEOTs are associated with an unerupted tooth.

86. CEOT: Histologic Features
This lesion is typically composed of islands, sheets or strands of polyhedral epithelial cells in a fibrous stroma.
Areas of amorphous, eosinophilic, hyalinized extracellular material may be scattered throughout.
Cells outlines are distinct and intercellular bridges may be seen.
Nuclei show considerable variation with giant nuclei and pleomorphism observed.
Calcifications may be noted as well as amyloid-like material. Liesegang rings also may be present.

87. CEOT: Additional Features, Treatment and Prognosis
Bony lesions most commonly present as painless, slow-growing swellings.
Peripheral lesions typically appear as non-specific sessile gingival masses.
Conservative local resection is the treatment of choice as these lesions are typically less aggressive than the ameloblastoma.
With this treatment the recurrence rate is approximately 15 % and the overall prognosis is good.

95. Squamous Odontogenic Tumor (SOT): Clinical Features
Patient Age: Second through the seventh decades (mean 40 years).
Gender Predilection: None
Location: SOTs occur with about equal frequency in maxilla and mandible. They are more common in the anterior regions of the jaws than in the posterior. The lesions occur in the alveolar process.

96. SOT: Radiographic and Histologic Features
SOTs appear as non-specific radiolucent lesions. They may be well-circumscribed or ill-defined. They often appear triangular in shape and lateral to the tooth root.
Histologically, they appear as islands of bland-appearing squamous epithelium in a mature fibrous connective tissue stroma. The peripheral cells do not show the characteristic polarization seen in the ameloblastoma.

97. SOT: Additional Features, Treatment and Prognosis
SOTs often present as painless gingival swellings associated with tooth mobility. Approximately 25 % are asymptomatic.
Conservative local excision or curettage appears to be effective treatment and there have only be a few recurrences reported.

102. Mixed Odontogenic Tumors
This group of tumors is composed of proliferating odontogenic epithelium in a cellular ectomesenchyme resembling the dental papilla.

103. Ameloblastic Fibroma: Clinical Features
This true mixed odontogenic tumor is more common in patients in the first and second decades of life with a mean of 14 years.
It is slightly more common in males than females.
Approximately 70 % of the ameloblastic fibromas occur in the posterior mandible.

104. Ameloblastic Fibroma: Radiographic Features
Generally, these lesions appear as either a unilocular or multilocular radiolucency.
They tend to be well-defined and may have a sclerotic border.
Approximately, 50 % are associated with an unerupted tooth.

105. Ameloblastic Fibroma: Histologic Features
The tumor is composed of a cell-rich mesenchymal tissue resembling the primitive dental papilla admixed with proliferating odontogenic epithelium.

106. Ameloblastic Fibroma: Additional Features, Treatment and Prognosis
The tumor is often encapsulated with small tumors usually being asymptomatic. Larger tumors produce swelling, which can expand the cortex and be quite pronounced.
Most ameloblastic fibromas are treated by conservative surgical excision; however, a 20 % recurrence rate has led some surgeons to recommend a more aggressive approach.

115. Ameloblastic Fibro-odontoma
This lesion is defined as a tumor with general features of an ameloblastic fibroma but containing enamel and dentin.
Some investigators believe that this entity is but a stage in the development of an odontoma; however, most agree that progressive destructive tumors are true neoplasms.

116. Ameloblastic Fibro-odontoma: Clinical and Radiographic Features
Patient Age: Most common in the 5-12 year age range with a mean of 10 years.
Gender Predilection: None.
Location: It is more common in the premolar/molar regions of both jaws.
Radiographic Features: Usually appears as a well-defined unilocular or rarely multilocular radiolucency with variable amounts of calcified material which is radiopaque. Therefore, it may appear as a mixed, radiolucent-radiopaque lesion.

117. Ameloblastic Fibro-odontoma: Histologic Features
The soft tissue component is identical to the ameloblastic fibroma. The calcified portion consists of foci of enamel and dentin matrix formation in close relationship to the epithelial structures.

118. Ameloblastic Fibro-odontoma: Treatment and Prognosis
The ameloblastic fibro-odontoma is usually treated by conservative curettage with the lesion separating easily from the surrounding bone.
Prognosis is excellent and recurrence is unusual.

124. Ameloblastic Fibrosarcoma
This lesion is considered the malignant counterpart of the ameloblastic fibroma in which the mesenchymal portion shows features of malignancy.
The ameloblastic fibrosarcoma may arise de novo or there may be a malignant transformation of an ameloblastic fibroma.

125. Ameloblastic Fibrosarcoma: Clinical and Radiographic Features
Patient Age: The mean age for patients with ameloblastic fibrosarcoma is 26 years.
Gender Predilection: Males 2:1.
Location: 75 % have occurred in the mandible.
Radiographic Features: Appear as an ill-defined, destructive, radiolucent lesion.

126. Ameloblastic Fibrosarcoma: Histologic Features
The epithelial component of this tumor appears histologically benign.
The mesenchymal portion is highly cellular. The cells are hyperchromatic and quite pleomorphic. Mitoses are usually prominent.

127. Ameloblastic Fibrosarcoma: Additional Features, Treatment & Prognosis
Pain and swelling are typically associated with this tumor. Rapid clinical growth is another common feature.
Radical surgical excision is the treatment of choice.
The long-term prognosis is difficult to ascertain because of the small number of reported cases.

131. Odontoameloblastoma (Ameloblastic Odontoma): Clinical Features
Extremely rare tumor, thus there is little reliable information.
Patient Age: Has been seen in younger patients.
Gender Predilection: Unknown.
Location: Most cases have been in mandible.
Radiographic Appearance: Lesion is a mixed radiolucent-radiopaque, ill-defined one.

132. Odontoameloblastoma: Histologic Features
The epithelial portion of the tumor has the features of an ameloblastoma, most often with a plexiform or follicular pattern.
The odontoma portion of the lesion is composed of enamel, dentin, and cementum with either a compound or complex pattern.

133. Odontoameloblastoma: Treatment and Prognosis
Since multiple recurrences have been reported following local curettage, the lesion should be treated as an ameloblastoma with marginal resection.
No valid data on long-term prognosis is available due to the small number of cases.

139. Odontoma The odontoma is the most common odontogenic tumor.
It is not a true neoplasm but rather is considered to be a developmental anomaly (hamartoma).
Two types of odontomas are recognized:
Compound: this type of odontoma is composed of multiple small tooth-like structures.
Complex: this lesion is composed of a conglomerate mass of enamel and dentin, which bears no anatomic resemblance to a tooth.

140. Odontoma: Clinical Features
Patient Age: Most cases are recognized during the second decade of life with a mean of 14 years.
Gender Predilection: Approximately equal.
Location: Somewhat more common in the maxilla. The compound type is more often in the anterior maxilla while the complex type occurs more often in the posterior regions of either jaw.

141. Odontoma: Radiographic Features
Early lesions are radiolucent with smooth, well-defined contours.
Later a well-defined radiopaque appearance develops.
The compound type shows apparent tooth shapes while the complex type appears as a uniform opaque mass with no apparent tooth shapes present.

142. Odontoma: Additional Features
Most odontomas are small and do not exceed the size of a normal tooth in the region.
However, large ones do occur and these may cause expansion of the jaw.
Most odontomas are asymptomatic and as a result are discovered upon routine radiographic examination.
Odontomas may block the eruption of a permanent tooth and in these cases are often discovered when “searching for” the “missing” tooth radiographically.

143. Odontoma: Histologic Features
The compound odontoma is composed of enamel, dentin and cementum arrange in recognizable tooth forms; some enamel matrix may be retained in immature and hypomineralized specimens.
The complex odontoma is composed of enamel, dentin and cementum but these tissues are arranged in a random manner that bears no morphological resemblance to a tooth.

144. Odontoma: Treatment and Prognosis
Odontomas are treated by simple local excision and the prognosis is excellent.

152. Tumors of Odontogenic Ectomesenchyme

153. (Central) Odontogenic Fibroma: Clinical Features
Fewer than 70 cases have been reported in the English literature. (VS hyperplastic follicle when associated with unerupted tooth)
Patient Age: Patients have ranged in age from 9-80 years old with a mean of 40 years.
Gender Predilection: Females, 7.4:1 in one study.
Location: Sixty percent occur in the maxilla where most are located anterior to the first molar. When in the mandible, approximately 50 % occur in the posterior jaw.

154. Odontogenic Fibroma: Radiographic Appearance
The odontogenic fibroma usually appears as a well-defined, unilocular radiolucency. It is often associated with the apical area of an erupted tooth.
Larger lesions are often multilocular.
Many odontogenic fibromas have sclerotic borders.
Root resorption is common.

155. Odontogenic Fibroma: Additional Features
Small odontogenic fibromas are usually asymptomatic.
The larger lesions may be associated with localized bony expansion of the jaw or with the loosening of adjacent teeth.

156. Odontogenic Fibroma: Histologic Features
Some authors have described two separate types of odontogenic fibromas.
The simple odontogenic fibroma is composed of stellate fibroblasts arranged in a whorled pattern with fine collagen fibrils and a lot of ground substance.
Foci of odontogenic epithelium may or may not be present.
Occasionally, foci of dystrophic calcification may be present.

157. Odontogenic Fibroma: Histologic Features
The WHO type odontogenic fibroma appears as a fairly cellular fibrous connective tissue with collagen fibers arranged in interlacing bundles.
Odontogenic epithelium in the form of long strands or isolated nests is present throughout the lesion.
Calcifications composed of cementoid and/or dentinoid may be present.

158. Odontogenic Fibroma: Treatment and Prognosis
The odontogenic fibroma is usually treated by enucleation and curettage.
There have been few recurrences, this the prognosis is good.

164. Peripheral Odontogenic Fibroma (POF): Clinical & Radiographic
Patient Age: POFs are seen over a wide age range.
Gender Predilection: This is unknown.
Location: Most POFs occur on the facial gingiva of the mandible.
Radiographic Appearance: The lesion does not involve the underlying bone but areas of calcification may be seen in the soft tissues in some cases.

165. POF: Histologic & Additional Features
The POF is histologically similar to the central odontogenic fibroma, WHO type.
POFs generally present as firm, slow-growing, usually sessile, masses covered by normal-appearing oral mucosa.
They may cause tooth displacement.

166. POF: Treatment and Prognosis
Local surgical excision is the treatment of choice and the prognosis is excellent.
There is little to no tendency for recurrence.

170. Granular Cell Odontogenic Tumor
Granular Cell Odontogenic Fibroma
Less than 25 cases have been reported

171. Granular Cell Odontogenic Tumor: Clinical and Radiographic Features
Patient Age: Almost all the patients have been over the age of 40 years.
Gender Predilection: This is unknown.
Location: The lesion has been seen in both the maxilla and mandible; most often in in molar regions.
Radiographic Appearance: Typically appears as a well-demarcated radiolucency which may have some areas of opacity.

172. Granular Cell Odontogenic Tumor: Histologic Features
The tumor is composed of large eosinophilic granular cells.
Narrow cords or small islands of odontogenic epithelium are scattered among the granular cells.
The nature of the granular cells is controversial (?? lysosomal structures??).

173. Granular Cell Odontogenic Tumor: Treatment and Prognosis
Curettage has been the method of treatment and no recurrences have been reported.

176. Odontogenic Myxoma: Clinical and Radiographic Features
Patient Age: years with a mean around 30 years.
Gender Predilection: Reported to be about equal.
Location: May occur in any area of the jaws but more common in the mandible.
Radiographic Appearance: Radiolucent lesion often with a multilocular appearance. The borders may be indistinct.

177. Odontogenic Myxoma: Histologic Features
The tumor is composed of loosely arranged stellate, spindle-shaped and round cells in an abundant, loose myxoid stroma with few collagen bundles.
Epithelial cells are not required for diagnosis.
The odontogenic myxoma may be confused with a chrondromyxoid fibroma or with myxoid change in an enlarged dental follicle or papilla.

178. Odontogenic Myxoma: Treatment and Prognosis
Small odontogenic myxomas are treated by curettage, while larger lesions may require surgical resection.
Odontogenic myxomas are not encapsulated and tend to infiltrate adjacent tissues.
Recurrence rates of up to 25 % are reported.
Overall, the prognosis is good for most odontogenic myxomas.

184. Cementoblastoma (True Cementoma): Clinical Features
Patient Age: This lesion is most commonly occurs in the second and third decades.
Gender Predilection: Approximately equal.
Location: The cementoblastoma is associated with the roots of posterior teeth and is more common in the mandible than the maxilla.

185. Cementoblastoma: Radiographic and Histologic Features
Radiographically, the lesion appears as an opaque lesion attached to and replacing the root of the involved tooth.
Opaque spicules radiate from the central mass.
The lesion is composed of sheets or thick trabeculae of mineralized material with irregularly placed lacunae and prominent basophilic reversal lines. Multinucleated giant cells are often present.
This lesion closely resembles the osteoblastoma.

186. Cementoblastoma: Additional Features, Treatment and Prognosis
The cementoblastoma is a slow-growing lesion that may cause local expansion of the jaw.
Pain may or may not be associated with the lesion but the cementoblastoma is usually asymptomatic.
The usual treatment consists of surgical extraction of the tooth together with the attached mass; occasionally there are attempts to save the tooth.
The prognosis is excellent as the lesion does not recur.