Ameloblastoma- Guide to an updated short review on the odontogenic neoplasm of the oral cavity

Abstract

Ameloblastoma, the word has developed from the very early English words that are— ‘Amel’ meaning enamel, and ‘blastos’— meaning the germ. It is a benign locally aggressive neoplasm originating from the odontogenic epithelium. It is also the most common odontogenic neoplasm in the oral cavity.

Full text

Journal of Oral Medicine, Oral Surgery, Oral Pathology and Oral Radiology 2023;9(2):72–74
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Mini Review
Ameloblastoma- Guide to an updated short review on the odontogenic neoplasm of
the oral cavity
Siddharth Kumar Singh1, Tushar Mathur1, Anjali Gupta2,*, Sayak Roy3
1Dept. of Oral Medicine and Radiology, Saraswati Dental College, Lucknow, Uttar Pradesh, India
2Dept. of Dentistry, Saraswati Medical College, Unnao, Uttar Pradesh, India
3Dept. of Oral Medicine & Radiology, Dafodyl Dental Clinic, Kolkata, West Bengal, India
ARTICLE INFO
Article history:
Received 22-11-2022
Accepted 04-04-2023
Available online 02-06-2023
Keywords:
Ameloblastoma
Egg shell crackling
Soapbubble appearance
Odontogenic
Mandible
ABSTRACT
Ameloblastoma, the word has developed from the very early English words that are— ‘Amel’ meaning
enamel, and ‘blastos’— meaning the germ. It is a benign locally aggressive neoplasm originating from the
odontogenic epithelium. It is also the most common odontogenic neoplasm in the oral cavity.
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1. Introduction
Ameloblastoma is a tumor that is locally invasive in
nature and arises from the odontogenic epithelium with no
influence on the ectomesenchyme. It usually occurs in the
jawbones with a more predilection towards the mandible.1
The etiological factors are not known however, the
following factors may predispose the formation of
ameloblastoma:2
1. Any trauma in the oral cavity
2. Viral and other infections
3. Previous inflammation locations
4. Extractions and early removal of tooth
5. Nutritive and dietary factors.2
Clinically ameloblastoma is a painless, slowly expanding,
elliptical or fusiform, hard bony swelling of the jaw.3
Histologically ameloblastomas may be present in several
forms such as:
* Corresponding author.
E-mail address:anjali462007@gmail.com (A. Gupta).
1. Plexform pattern
2. Follicular pattern
3. Acanthomatous pattern
4. Basal cell pattern
5. Granular cell pattern
6. Desmoplastic pattern
Amongst these plexiform and follicular patterns are the
commonest.
The World Health Organization (WHO) in 1991
defined ameloblastoma as a benign and locally aggressive
tumor with an elevated tendency to recur, comprising of
proliferating odontogenic epithelium lying in the fibrous
stroma.3
The tumor derives from the residual or remaining
epithelium of the tooth germ, enamel organ epithelium,
epithelium of odontogenic cysts or the stratified squamous
epithelium.4
Ameloblastoma was first described by Cusack in 1827
where as the term ameloblastoma was coined by Ivey and
Churchill in the year 1930.5
https://doi.org/10.18231/j.jooo.2023.016
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Singh et al. / Journal of Oral Medicine, Oral Surgery, Oral Pathology and Oral Radiology 2023;9(2):72–74 73
2. Classification
According to WHO in 2005 with the latest modifications
and amendments made in the year 2017, classified
ameloblastoma as a benign tumor with odontogenic
epithelium and a mature fibrous stroma exclusive of the
odontogenic ectomesenchyme.3
-Ameloblastoma is classified into:
1. Multicystic/Conventional Ameloblastoma (also
known as Solid Ameloblastoma).
2. Unicystic Ameloblastoma (also known as Cystic
Ameloblastoma).
3. Peripheral Ameloblastoma [WHO-2005].
Chart 1: Flowchart with the new classification of
ameloblastomas - WHO20174
2.1. Clinical Features
1. Incidence: Ameloblastoma itself accounts for about
1% of all oral tumors. The peak occurrence lies in
the third to fourth decades of life whereas the Male:
Female prevalence ratio is 1:1.4
2. This lesion occurs more commonly in people with a
dark complexion and blacks than whites.4
3. Site: Ameloblastoma in most of the cases involve the
mandible (80%), especially in the molar-ramus area.5
2.1.1. Clinical presentation
1. The lesion causes distortion and expansion of the
cortical plates of the jawbone which may often lead
to gross facial asymmetry. The lesion may also be
responsible for the displacement of the regional teeth.3
Most of the patients report a typically long-time history
of the presence of an “abscess” or a ‘cyst” in the jaw
bone that was operated on several occasions but tends
to recur after some time.6
2. Expansion of the bony cortex occurs due to the slow
growth rate of the tumor which allows time for the
periosteum to develop a thin shell of bone over it
which cracks under digital pressure and produces a
characteristic noise known as the “eggshell crackling
Noise”. This phenomenon is one of the most significant
characteristic features of ameloblastoma.7
3. If the tumor arises in the maxillary region, the chances
of nasal obstruction or a pressure sensation in the
orbital region may be felt by the patient due to the
invasion and extension of the tumor into the maxillary
sinus, the orbit and the nasopharynx.7
2.1.2. Radiological features
1. A well-defined, multilocular radiolucency is
appreciated in the bone with a typical “honey-comb”
or “soap-bubble” appearance.8
2. In the radiograph, the lesion typically shows an
irregular and “scalloped” margin with sometimes the
resorption of roots of the adjoining normal teeth.7
2.1.3. Histopathological features
1. Histologically in ameloblastoma, Neoplastic
proliferation of the odontogenic epithelial cells
(ameloblast-like cells) occurs whereas the nucleus
moves away from the basement membrane which is
also known as the reverse polarization phenomenon.7
2. Histologically ameloblastomas may be present in
many forms such as;
(a) The follicular variant- It consists of central
portions of the neoplastic islands which are
loosely organized resembling the stellate
reticulum in a bud stage of a tooth germ. The
outer cells are columnar and palisaded having
reverse nuclear polarity.
(b) Plexiform variant- It comprises of a thin lamina
similar to strands. The cells are frequently
grouped in a double row of basaloid shape cells.
(c) Acanthomatous variant- There is central
squamous differentiation of the cells due to which
it may be mistaken for squamous cell carcinoma
or squamous odontogenic tumor.
(d) Desmoplastic variant- There is loss of marginal
palisading of the cells with a reverse nuclear
polarity which is brought by the tumor cells in
the stroma showing desmoplasia.
(e) Hybrid type- It is the mixture of usually two or
more variants.9
2.1.4. Treatment
The treatment of the ameloblastoma tumor preferably
includes resection with safety boundaries and immediate
reconstruction wherever and whenever possible.10
1. Small lesions are treated by bone curettage through
excisional biopsy approach.10
2. Multilocular or Unilocular cystic lesions are treated
by Enucleation and Bone Curettage and sometimes
Marginal Resection.10
3. Solid lesions with clear or unclear boundaries are
treated by marginal or segmental resection.10

74 Singh et al. / Journal of Oral Medicine, Oral Surgery, Oral Pathology and Oral Radiology 2023;9(2):72–74
3. Conclusion
For the reason that ameloblastoma has a very low prevalence
and poor symptoms, it is very difficult to diagnose in the
early stages.
It is very important to correlate and associate all the
histopathologic findings with the clinical and radiographic
features to reach a definitive diagnosis and only then
through radiotherapy, surgical approach, or a therapeutic
decision could be decided for the needful.
4. Source of Funding
None.
5. Conflict of Interest
None.
References
1. Peter AR, Philipsen HA. Odontogenic Tumors and Allied Lesions. 1st
ed. London: Quintessence; 2004. p. 43–58.
2. Rajendran R. Cyst and tumors of odontogenic origin. In: Rajendran R,
Sivapathasundharam B, editors. Shafer’s Text Book of Oral Pathology.
Noida: Elsevier; 2012. p. 259–313.
3. Nakamura N, Mitsuyasu T, Higuchi Y, Sandra F, Ohishi M. Growth
characteristics of ameloblastoma involving the inferior alveolar nerve:
A clinical and histopathologic study. Oral Surg Oral Med Oral Pathol
Oral Radiol Endod. 2001;91(5):557–62.
4. Barnes L, Eveson JW, Reichart P, Sidransky D. World Health
Organization Classification of Tumors: Head and Neck Tumors. Lyon,
France: IARC Press; 2005.
5. Fregnani ER, Fillipi RZ, Oliveira C, Vargas PA, Almeida OP.
Odontomas and ameloblastomas: variable prevalences around the
world? Oral Oncol. 2002;38(8):807–8.
6. Ghai S. Ameloblastoma: An Updated Narrative Review of an
Enigmatic Tumor. Cureus. 2022;14(8):e27734.
7. Purkait SK. Essentials of Oral Pathology. Delhi: Jaypee Brothers;
2005.
8. Dunfee BL, Sakai O, Pistey R, Gohel A. Radiologic and pathologic
characteristics of benign and malignant lesions of the mandible.
Radiographics. 2006;26:1751–68.
9. Shetty UA, Pousya VS, Bhandary S, Gadkari SN, Paiwal K,
Rajendrakumar PN. Ameloblastoma-A rigorous odontogenic tumors
of the jaws: A regional retrospective analysis. Int J Health Sci.
2022;6(S5):8736–47.
10. Dandriyal R, Gupta A, Pant S, Baweja HH. Surgical management of
ameloblastoma: Conservative or radical approach. Natl J Maxillofac
Surg. 2011;2(1):22–7.
Author biography
Siddharth Kumar Singh, Professor
Tushar Mathur, Lecturer
Anjali Gupta, Professor
Sayak Roy, Consultant
Cite this article: Singh SK, Mathur T, Gupta A, Roy S.
Ameloblastoma- Guide to an updated short review on the odontogenic
neoplasm of the oral cavity. J Oral Med, Oral Surg, Oral Pathol, Oral
Radiol 2023;9(2):72-74.