SciELO - Scientific Electronic Library Online

vol.6 número3Cóndilo Mandibular Bífido: Un Desafío DiagnósticoDeformidad Facial Asimétrica: Papel de la Hiperplasia Condilar índice de autoresíndice de materiabúsqueda de artículos
Home Pagelista alfabética de revistas  

Servicios Personalizados




Links relacionados


International journal of odontostomatology

versión On-line ISSN 0718-381X

Int. J. Odontostomat. vol.6 no.3 Temuco  2012 

Int. J. Odontostomat., 6(3): 331-336, 2012.

Mandibular Ameloblastoma in a 10-year-old Child: Case Report and Review of the Literature

Ameloblastoma Mandibular en Niño de 10 Años: Reporte de un Caso y Revisión de la Literatura

Edgar Belardo*; Ignacio Velasco**; Andrés Guerra* & Edwin Rosa"

* Professor, Department of Oral and Maxillofacial Surgery, University of Puerto Rico, Puerto Rico.
** Resident, Department of Oral and Maxillofacial Surgery, University of Puerto Rico, Puerto Rico.

Dirección para correspondencia

ABSTRACT: The ameloblastoma according to the classification of odontogenic tumors by WHO in 2005, is classified as a benign neoplasm of odontogenic epithelial origin. One to three percent of tumors and cysts of the jaws are comprised of ameloblastomas. The tumor is locally aggressive, but often asymptomatic, showing a slow growth which is manifested as a facial swelling or radiographic incidental finding. On clinical examination, the tumor can cause symptoms such as pain, ulceration, tooth mobility, root resorption and malocclusion. Ameloblastomas have a high rate of recurrence if not completely removed. It occurs in almost all age groups, but is mainly diagnosed in the third or fourth decade of life. The tumor is very rare in children. We present an unusual case of a solid/multicystic ameloblastoma of the mandible in a 10-year-old girl. In addition, a brief review of the literature on reported cases of this pathology in children is also presented.

KEY WORDS: solid ameloblastoma, multicystic ameloblastoma, odontogenic tumor, children.

RESUMEN: El ameloblastoma según la clasificación de tumores odontogénicos de la OMS del 2005 lo clasifica como una neoplasia benigna de origen epitelial odontogénico. Compromete el 1-3% de neoplasias y quistes maxilares. El tumor es agresivo localmente, pero muchas veces asintomático; presenta un lento crecimiento que se manifiesta como un aumento de volumen facial o un hallazgo incidental radiográfico. Al examen clínico el tumor puede causar síntomas como dolor, ulceración, reabsorción radicular con movilidad dentaria y maloclusión. El ameloblastoma posee gran tasa de recurrencia si no es totalmente removido. Se presenta en casi todos los grupos etarios pero principalmente se diagnostica en la tercera o cuarta década de vida, el tumor es muy poco común en niños. El tratamiento del ameloblastoma es controversial y debido a la distinta incidencia y comportamiento en niños, hace las consideraciones quirúrgicas diferentes a los adultos. Por lo que presentamos un inusual caso de un ameloblastoma solido/multiquístico mandibular en una niña de 10 años. Además de una breve revisión de la literatura sobre casos reportados de esta patología en niños.

PALABRAS CLAVE: ameloblastoma solido, ameloblastoma multiquístico, tumores odontogénicos, niños.


The ameloblastoma according to the classification of odontogenic tumors by WHO in 2005, is classified as a benign neoplasm of odontogenic epithelial origin (Barnes et al., 2005). One to three percent of tumors and cysts of the jaws are comprised of ameloblastomas (Small & Waldron, 1995; Reichart et al., 1995). Ameloblastoma is the most common odontogenic tumor (OT) in Africa (Arotiba et al., 1997; Ladeinde et al., 2005) and Asia (Wu & Chan, 1985) but is the second most common in South and North America (Regezi et al., 1978; Ochsenius et al., 2002).

Ameloblastoma can theoretically arise from remnants of the dental lamina, enamel organ of developing tooth, the epithelial lining of odontogenic cyst or basal cells of the oral mucosa (Crawley & Levin, 1978; Leider et al., 1985). It occurs in almost all age groups, but mainly diagnosed in the third or fourth decade of life. Most cases (66%) affect the posterior mandible and ramus (Neville et al., 2008). Ameloblastomas are usually asymptomatic and present as a slow growing facial swelling or as an incidental radiographic finding. Despite being a benign neoplasm, it is locally destructive and has a high rate of recurrence if not completely removed (Hong et al., 2007). The three clinical and radiographic presentations which have different prognostic and therapeutic considerations can include: 1) solid/ multicystic (86% of cases); 2) unicystic (13% of cases); 3) peripheral (1% of cases) (Neville et al.).

Its classic radiographic presentation is that of a multilocular radiolucency. The expansion of the buccal and lingual cortices of bone, with the possibility of bone perforation and soft tissue extension is frequently observed. The resorption of roots of adjacent teeth is common and is often associated with an unerupted tooth. Most frequently, it is the mandibular third molar area which is involved (Dunfee et al., 2006). However, the solid/multicystic ameloblastoma may appear radiographically as a unilocular lesion resembling other cystic lesion (Hong et al.).

The clinico-pathologic characteristics are of a benign lesion with a slow growth pattern, but locally invasive. The clinical behavior can be considered between a benign and malignant lesion, and the high rate of recurrence is an important factor when determining the management of the lesion (Chapelle et al., 2004). Therefore, the choice of treatment should be assessed based on the lesion's clinical type (solid/multicystic, unicystic, peripheral), the location and size of tumor and patient's age. The spectrum of treatment described in the literature range from simple bone curettage to segmental resection, but there are few criteria for treatment based on retrospective studies published.

In this report we present the unusual case of a solid/multicystic ameloblastoma in the mandible of a 10-year-old girl. In addition, a brief review of the literature on reported cases of this pathology in children is also presented.


Fig. 1. a-b. Extraoral photographs showed mild facial swelling over the body of the left mandible.

Fig. 2. a-b. Intraoral photographs showed remarkable buccal and lingual expansion of left mandibular body.

The patient is a 10-year-old Hispanic female, without history of medical conditions. She was consulted to the Oral and Maxillofacial Surgery Clinic at the University Pediatric Hospital (UPH) at the Medical Center in San Juan, Puerto Rico, due to a painless facial swelling in the left perimandibular area with three months of evolution. Extraoral clinical examination showed a mild facial swelling over the body of the left mandible, which was firm to palpation with a normal overlying skin (Fig. 1).

Intraorally, the exam was remarkable for a buccal and lingual expansion of the mandibular left body, tender to palpation and covered with normal, healthy mucosa (Fig. 2). There were neither palpable neck masses nor lymphadenopathy and all cranial nerves were intact. The remaining physical exam was within normal limits. The patient had no relevant medical history and was taking no medication.

The panorex and maxillofacial computed tomography (CT) requested revealed an extensive unilocular and radiolucent lesion with diffuse margins, localized to the left mandibular body extending from the canine to the first molar (3.6 cm antero-posterior and 2.3 cm width) and including the second premolar inside the lesion. Reabsorbtion of the roots of adjacent teeth and expansion of the buccal and lingual cortical plates with evident perforation in some areas were also noted (Fig. 3).

Fig. 3. a- Panorex showed extensive unilocular, radiolucent lesion of left mandibular body and including the second premolar inside the lesion, b- CT axial views of bone window, the dimensions of the lesion were: 3.6 cm antero-posterior and 2.3 cm width.

Fig. 4. Histopathology, hematoxylin-eosin stain, original magnification 100x.

The primary differential diagnoses contemplated for this lesion included an odontogenic cyst vs. an odontogenic tumor, however, a vascular lesion has to be always considered. The lesion was first aspirated prior to the extraction of the lower left deciduous first molar, through which an incisional biopsy was performed. Diagnostic hypothesis included: dentigerous cyst, primordial cyst, adenomatoid odontogenic tumor, keratocystic odontogenic tumor and unicystic ameloblastoma.

Fig. 5. a. Submandibular approach to mandible. b. Mandibular resection and reconstruction plate placement.

The histopathologic examination demonstrated continuing islands of odontogenic epithelium set in a fibrous stroma. The epithelium consisted of basal cells resembling the enamel organ, showing cytoplasmic vacuolization and reverse polarization of the nuclei that resulted in solid/multicystic ameloblastoma (Fig. 4). The patient underwent treatment with a mandibular resection with safety margins of 1 cm, through a submandibular approach along with placement of a 2.4 mm mandibular reconstruction plate (KLS Martin LP, Jacksonville, Florida) (Fig. 5). Specimen X-Ray was obtained to check the bony margins (Fig. 6).

Fig. 6. a. Surgical specimen. b. intraoperative radiography. cases of ameloblastomas in children from 1970 to

Fig. 7. Panorex, 1 day post-operative.

Post-operative radiographic evaluation showed adequate resection margins (Fig. 7) and the final pathology was consistent with the initial diagnosis of solid/multicystic ameloblastoma. The patient has had an uneventful recovery and at this time she is being observed for spontaneous regeneration of the mandible and will be scheduled for reconstructive surgery in the future. She will be followed every three months for the first year, and then twice a year for the next 4 years.


Ameloblastoma is uncommon in children. The most commonly cited article is a review of 1.036 cases, where the average age was 38.9 years with only 2.2% (19 of 858) under 10 years and 8.7% (75 of 858) between 10 and 19 (Small & Waldron). However, this report was published in 1955 when adenoameloblastoma and ameloblastic fibroma were considered ameloblastomas. The first report of ameloblastoma in children was in 1962, where 7 cases were reported in children under the age of 9 years old but 2 of these cases were ameloblastic fibromas and 1 case odontoameloblastoma (Young & Robinson, 1962).

Ord et al. (2002) made a review of reported 2001, comparing Western and African reports. This review showed an average age of 14.3 years (Western) and 14.7 years (African) and confirms that less than 10% of cases occur in children under 10-years-old. In adults, the gender ratio is 1:1. In Western children the ratio is 1:1.2 for male/female. While in African children, there is a male predominance of 1.4:1. The mandible is the most affected in adult ameloblastomas (85%), the third molar region being the most common site. This pattern is reflected in Western children where the angle of the mandible is affected 72% and the mandibular symphysis 5.8%. In contrast, African children were affected in the angle of the mandible 27.3% and in the mandibular symphysis 44.2%. The unicystic ameloblastoma variant is more common in Western children (76.5%). The solid/multicystic ameloblastoma is rare in children but in African children is the most prevalent (59.8%) assimilating the adult pattern.

Ameloblastoma treatment in children would be complicated by 3 factors (Ord et al.):

1) The continued growth and facial bone physiology (higher percentage of cancellous bone, increased bone turnover and high periosteal reactivity), as well the presence of unerupted teeth.

2) Difficult initial diagnosis.

3) Predominance of AB unicystic type.

The diagnosis of ameloblastoma in children is difficult because most of the lesions radiographically resemble dentigerous cyst. Studies associate ameloblastoma with an unerupted tooth in the range of 70% to 83%, and in our case is associated with a second premolar but is most frequently associated with the mandibular third molar (Robinson & Martinez, 1977; Shteyer et al., 1978). This radiographical similarity with dentigerous cyst would lead to initial treatment, marsupialization, curettage or enucleation. And only when the specimen is analyzed completely, definitive diagnosis is made and at that point one it should be determined if another treatment is necessary.

The basis of treatment in adults is surgery, resection with safety margins of 1-1.5 cm is recommended due to the high rate of recurrence of the solid/multicystic ameloblastoma. The recurrence rate after resection is close to 5% compared with the 90-100% of the curettage and enucleation (Chapelle et al.).

In the treatment of children some authors recommend enucleation or only minimal treatment (Rapidis et al., 1982; Isaacsson et al., 1986), while Fung et al. (1978) suggests that due to the greater amount of cancellous bone in young patients, the lesion would have a more aggressive course with more destruction, making the surgical procedure more difficult and demanding.

Ameloblastoma management remains controversial, but Ord et al. states that the solid/ multicystic ameloblastoma or recurrent lesions in children should be treated with mandibular resection in the same way adults are treated. Their cases are treated with mandibular resection with a safety margin of 1 cm of cancellous bone and soft tissue resection if there was cortical perforation. Our reported case was treated in this way with reconstruction plate placement. Monitoring is essential in these patients because most recurrences occur within the first 5 years. However, some recurrences have been observed beyond 10 years after initial treatment (Dunfee et al.).


Arotiba, J. T.; Ogunbiyi, J. O. & Obiechina, A. E. Odontogenic tumours: a 15-year review from Ibadan, Nigeria. Br. J. Oral Maxillofac. Surg., 35(5):363-7, 1997.         [ Links ]

Barnes, L.; Eveson, J. W.; Reichart, P. & Sidransky, D. World health organization classification of tumours: Head and neck tumours. Lyon, France, IARC Press, 2005. pp.284-302.         [ Links ]

Chapelle, K. A.; Stoelinga, P. J.; de Wilde, P. C.; Brouns, J. J. & Voorsmit, R. A. Rational approach to diagnosis and treatment of ameloblastomas and odontogenic keratocysts. Br. J. Oral Maxillofac. Surg., 42(5):381-90, 2004.         [ Links ]

Crawley, W. A. & Levin, L. S. Treatment of the ameloblastoma: a controversy. Cancer, 42(1):357-63, 1978.         [ Links ]

Dunfee, B. L.; Sakai, O.; Pistey, R. & Gohel, A. Radiologic and pathologic characteristics of benign and malignant lesions of the mandible. Radiographics, 26(6):1751-68, 2006.         [ Links ]

Fung, E. M. Ameloblastomas. Int. J. Oral Surg., 7:305, 1978.         [ Links ]

Hong, J.; Yun, P. Y.; Chung, I. H.; Myoung, H.; Suh, J. D.; Seo, B. M.; Lee, J. H. & Choung, P. H. Long-term follow up on recurrence of 305 ameloblastoma cases. Int. J. Oral Maxillofac. Surg., 36(4):283-8, 2007.         [ Links ]

Isaacsson, G.; Andersson, L.; Fosslund, H.; Bodin, I. & Thomsson, M. Diagnosis and treatment of unicystic ameloblastoma. Int. J. Oral Maxillofac. Surg., 15(6):759-64, 1986.         [ Links ]

Ladeinde, A. L.; Ajayi, O. F.; Ogunlewe, M. O.; Adeyemo, W. L.; Arotiba, G. T.; Bamgbose, B. O. & Akinwande, J. A. Odontogenic tumors: a retrospective analysis of 319 cases in a Nigerian teaching hospital. OralSurg. OralMed. OralPathol. Oral Radiol. Endod., 99(2):191-5, 2005.         [ Links ]

Leider, A. S.; Eversole, L. R. & Barkin, M. E. Cystic ameloblastoma: A clinicopathologic analysis. Oral Surg. Oral Med. Oral Pathol., 60(6):624-30, 1985.         [ Links ]

Neville, B. W.; Damm, D. D.; Allen, C. M. & Bouqout, J. Oral and Maxillofacial Pathology. 3rd ed. St. Louis, Saunders, 2008. pp.701-8.         [ Links ]

Ochsenius, G.; Ortega, A.; Godoy, L.; Penafiel, C. & Escobar, E. Odontogenic tumors in Chile: a study of 362 cases. J. Oral Pathol. Med., 31(7):415-20, 2002.         [ Links ]

Ord, R. A.; Blanchaert, R. H. Jr.; Nikitakis, N. G. & Sauk, J. J. Ameloblastoma in children. J. OralMaxillofac. Surg., 60(7):762-70, 2002.         [ Links ]

Rapidis, A. D.; Angelopoulos, A. P.; Skouteris, C. A. & Papanicolaou S. Mural (intracystic) ameloblastoma. Int. J. Oral Surg., 11(3):166-74, 1982.         [ Links ]

Regezi, J. A.; Kerr, D. A. & Courtney, R. M. Odontogenic tumours: analysis of 706 cases. J. Oral Surg., 36(10):771-8, 1978.         [ Links ]

Reichart, P. A.; Philipsen, H. P. & Sonner, S. Ameloblastoma: biological profile of 3677 cases. Eur. J. Cancer B Oral Oncol., 31B(2):86-99, 1995.         [ Links ]

Robinson, L. & Martinez, M. G. Unicystic ameloastoma: A prognostically distinct entity. Cancer, 40(5):2278-85, 1977.         [ Links ]

Shteyer, A.; Lustmann, J. & Lewis-Epstein, J. The mural ameloblastoma: A review of the literature. J. Oral Surg., 36(11):866-72, 1978.         [ Links ]

Small, L. A. & Waldron, C. A. Ameloblastoma of the jaws. Oral Surg. Oral Med. Oral Pathol., 8:281-97, 1955.         [ Links ]

Wu, P. C. & Chan, K. W. A survey of tumours of the jaw bone in Hong Kong Chinese: 1963-1982. Br. J. Oral Maxillofac. Surg., 23(2):92-102, 1985.         [ Links ]

Young, D. R. & Robinson, M. Ameloblastomas in children. Oral Surg. Oral Med. Oral Pathol., 15:1155-62, 1962.         [ Links ]

Correspondence to:
Dr. Ignacio Velasco Martinez.
Av. Pasaje Republica de Honduras interior 12.279
Zip: 7550000

Received: 13-04-2012
Accepted: 26-06-2012

Creative Commons License Todo el contenido de esta revista, excepto dónde está identificado, está bajo una Licencia Creative Commons