4. Odontogenic myxoma
• Definition: Odontogenic myxoma is a rare, benign intraosseous tumor.
• It is non-encapsulated, arises from odontogenic ectomesenchyme,
develops solely in the jaws, and represent a small percentage of
odontogenic tumor overall.
5. Definition & Clinical Findings
• Clinical Symptoms:
• May or may not be symptomatic
• Symptoms include:
• Facial asymmetry
• Abnormal growth
• Swelling
• Pain
• Numbness
• Nosebleeds
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3800391/
6. Definition & Clinical Findings
• Clinical Signs:
• Local invasion at the site of the tumor
• Local invasion of surrounding structures
• Tooth mobility
• Ulceration
• Root resorption
• Encroachment of the mandibular canal
• Invasion of the maxillary sinus
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3800391/
7. Definition & Clinical Findings
• Demographics:
• Favor Females
• 10-40 years old
• 3 times more common in mandible over maxilla
• Favor posterior region
• Second most common odontogenic tumor
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3800391/
8. Radiographic Findings:
• Location: Premolar and molar area of both the mandible and maxilla.
More commonly found in the mandible
• Edge: well-defined
• Shape: scalloped
• Internal structure: Radiolucent with trabeculae within, usually
multilocular
• Other: Displace adjacent teeth. May impinge the inferior alveolar
nerve and canal or extend into the maxillary sinus.
• Number: Single
• Size: Variable. Can become large
11. Histology
• Low-power photomicrograph illustrating loosely arranged stellate-
shaped cells with few collagen fibrils and capillaries (H and E ×10)
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3800391/
12. Histology
• High-power photomicrograph showing loosely arranged stellate-
shaped cells with intermingled fibrillar processes in a homogenous
mucoid ground substance (H and E ×40)
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3800391/
13. Differential interpretation
• Odontogenic Myxoma
• Likelihoods Ameloblastoma giant cell, granuloma and Central hemangioma
• Is second most common Odontogenic Tumor
• Can be found at posterior Mandible and Maxilla
• Usually present as a well-defined radiolucent
• Unilocular or multilocular area
• One or two straight septa is characteristic of OM
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5503096/
14. Treatment
1..Radical surgery -Should be carried out in the hope of preventing
recurrence, but this is not always successful.
2.Enucleation (cure recurrence myxoma following conservative
treatment)
3.Complete surgical removal of OMs by conservative treatment can be
difficult because unlike most benign neoplasms, they are not
encapsulated, and Myxomatous tissue infiltrates the surrounding bony
tissue without its immediate destruction.
4. Long-term followed-up Closely for first 2 years because this is the
period during which the neoplasm most likely to recure, although
sometimes recurrence mat appear much later.
15. Treatment
• Conservative surgical treatment
• Enucleation and curettage
• Difficult to fully remove
• Recurrence rate 25%
• Radio Surgical treatment
• Partial and full segmentation of maxilla and mandible
• Remove lesion with 1-2 of adjacent tissue
• Reduced risk of recurrence
• Follow-up for 2-15 years
• Refer to oral and maxillofacial surgeon
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5503096/
16. Key points
• Patients will present with facial asymmetry in either the posterior mandible
or maxilla. The tumor may become quite large if left untreated. OM has
potential to invade surrounding tissue and structures including unerupted
teeth, leading to potential tooth mobility or displacement.
• The radiographic findings are usually unilateral and in the posterior
mandible or maxillary tooth bearing regions. Internally , the tumor may
present as a radiolucent entity with fine septa within , or in a unilocular ,or
multilocular way. The border is usually well defined.
• The best treatment option for OM is radical surgical excision of the lesion
and the surrounding tissues. This treatment option has been found to have
less recurrences which reduces the number of surgeries required to
remove the lesion.
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5503096/
