Introduction
Ameloblastoma is an odontogenic neoplasm, and accounts 11-13% of all odontogenic tumors. It is aggressive, locally invasive persistent tumor that has benign characteristics of growth.1 It has three different types: 1) solid multicystic ameloblastoma (SMA); 2) unicystic ameloblastoma and 3) peripheral ameloblastoma.2 Desmoplastic ameloblastoma is considered as a distinct type because of its different biological behavior, radiographic feature and unique histopathology. These tumors are epithelial in origin. They can arise from: remnants of the dental lamina, developing enamel organ, epithelial lining of odontogenic cysts, offshoots of basal cells oral epithelium, heterotopic epithelium. (e.g., pituitary gland).3
Clinically, it usually presents itself as an asymptomatic swelling occurring most commonly in posterior mandible. It is frequently associated with an impacted tooth. It predominantly effect individuals aged between 30 and 60 years. There is no definite gender predilection. Conventional ameloblastoma radiographically represent as a unilocular or multilocular radiolucent lesion surrounded by a radiopaque border.4 Ameloblastoma has a tendency for expansion. Unicystic lesions present more commonly as unilocular radiolucency. The internal structure varies from totally radiolucent to a mixed radiolucent-radiopaque caused by presence of bony septae creating internal compartments, which may give rise to soap bubble, honeycomb, spider-like or mother-and-daughter cell appearances. The appearance of septae on the radiograph usually represents differential resorption of the cortical plate by the tumor and not actual separation of tumor portions.
Ameloblastoma can be divided histologically in four types: solid, unicystic, peripheral and desmoplastic. Based on its cellular and organization pattern, it can be divided into five subtypes: follicular, plexiform, acanthomatous, granular and basal cell. These types can occur as solitary lesion or in combination.5 The current study was carried out to evaluate cases of ameloblastoma in different age groups.
Materials and Methods
The present study was conducted in the department of Oral Pathology and Oral Medicine & Radiology. This study consists of 85 cases of ameloblastoma of both genders. The inclusion criteria were cases within specified age group and those giving consent to participate in the study. Exclusion criteria were cases with poor radiographs or with indefinite diagnosis and those unwilling to participate. The protocol was approved from ethical committee of institutional before the commencement of study.
General demographic characteristics such as age, gender, name etc. was recorded in case history performa. Other factors such as anatomical location and histopathological type etc. were also recorded. Type of treatment was also recorded. Patients were followed up regularly. Results obtained were tabulated on Microsoft excel sheet and subjected to statistical analysis. P value < 0.05 was considered as statistically significant.
Results
Table 1
Distribution of cases
| Total- 85 | ||
| Gender | Males | Females |
| Number | 55 | 30 |
[i] Table 1 revealed that out of 85 cases, males were 55 and females were 30.
Table 2
Distribution of histological subtypes based upon age of subject
| Types | 21-30 years | 31-40 years | 41-50 years | >50 years | Total |
| Plexiform | 15 | 8 | 7 | 5 | 35 |
| Follicular | 12 | 4 | 3 | 1 | 20 |
| Granular | 4 | 1 | 2 | 0 | 7 |
| Desmoplastic | 2 | 0 | 0 | 0 | 2 |
| Acanthomatous | 10 | 5 | 3 | 2 | 20 |
| Basal | 1 | 0 | 0 | 0 | 1 |
[i] Table 2 Idemonstrated that most common type was plexiform as it is seen in 35 patients, followed by follicular and acanthomatous ameloblastoma in 20 each, granular in 7, desmoplastic in 2 and basal in 1 patient. The difference was statistically significant (P< 0.05).
Table 3
Histological subtypes as per different Anatomical location
| Types | Maxilla | Mandible |
| Plexiform | 5 | 30 |
| Follicular | 8 | 12 |
| Granular | 2 | 5 |
| Desmoplastic | 2 | 0 |
| Acanthomatous | 7 | 13 |
| Basal | 1 | 0 |
| Total | 25 | 60 |
[i] Table 3 shows that 25 cases were seen in maxilla and 60 were in mandible. The difference was significant (P< 0.05).
Figure 1 shows that in most of the cases (67 cases) treatment given was enucleation and radical surgery in only 18 cases which showed statistically significant difference (P< 0.05).
Discussion
As per World Health Organization (2005) classification ameloblastoma is divided into 1) solid/multicystic, 2) extra-osseous/peripheral, 3) desmoplastic, and 4) unicystic (3). The solid/multicystic ameloblastoma can histopathologically be divided into a follicular and a plexiform type; the follicular type can be further subdivided into a spindle cell type, an acanthomatous type, a granular type and a basal cell type.6
In radiographs ameloblastoma are revealed as a unilocular or multilocular radiolucent lesion with sclerotic border. Bony septae may result in a honeycomb appearance. Roots resorption may or may not be observed.7 The radiographic differential diagnosis includes a variety of odontogenic cysts and tumours, particularly the odontogenic keratocyst, central giant cell granuloma, simple bony cyst and fibro-osseous lesions. Desmoplastic ameloblastoma characterized by a mottled, mixed radiolucency/radiopacity with diffuse margins, suggesting a fibro-osseous lesion.8 The current study was carried out to evaluate cases of ameloblastoma in different age groups.
In the present study, out of 85 cases, males were 55 and females were 30. The most common type seen was plexiform seen in 35 patients, followed by follicular and acanthomatous in 20 each, granular in 7, desmoplastic in 2 and basal in 1 patient. Arotiba et al9 observed in their study on 540 odontogenic tumors, 40 patients were having ameloblastomas with an overall prevalence rate of 7.4%. Males were frequently involved with male: female ratio of 1.8:1. Ameloblastoma affected individuals with age range between 21-60 years but most of them were seen in age group of 31-40 years. They observed follicular ameloblastoma as most common histological variant (42.5%) followed by acanthomatous type (32.5%). Two of the patients presented with the granular cell type which is considered as most aggressive form of ameloblastoma. The most frequent anatomical location of ameloblastoma was in the mandibular posterior area (87.5%) whereas maxillary posterior area was affected in 12.5% of the cases.
In the present study, 25 cases were observed in maxilla and 60 in mandible. In 67 cases enucleation and radical surgery in 18 cases were given as treatment. Chidzonga et al10 observed no statistically significant differences between the histopathological (sub) types of ameloblastomas and the demographical, clinical parameters, nor between the histopathological (sub) types and treatment outcome.
In present study, 67 cases treated with enucleation and radical surgery was done in 18 cases. The follow up for the study was 12- 26 months. We did not report recurrence in any of our study. Figueiredo et al.11 in their study on ameloblastoma found that the mean age in males was 23.25 ± 6.99 years, while that in females was 43.43 ± 17.13 years. Seven (63.63%) of the 11 subjects were females, and four (36.36%) were males. 10 (90.9%) of the 11 ameloblastomas were located in the mandible. Swelling was noted in all 11 patients. 10 cases showed radiographic findings, while one case was a peripheral soft-tissue variant. Seven (70%) of the 10 tumors were multilocular with a well-demarcated corticated border, and three cases (30%) were unilocular. Two cases showed a soap-bubble appearance. Histologically, five cases were unicystic, four were multicystic, one was desmoplastic and one was a peripheral variant. Follow-up ranged from 12 to 34 months and there were no signs of recurrence in any of the patients.
Ameloblastoma is common entity seen mostly in posterior mandible in molar, ramus region. Numerous studies have been done to assess cases of ameloblastoma. In our study we also tried to evaluate different histological type in different age groups. The limitation of present study is small sample size.
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