|Year : 2014 | Volume
| Issue : 2 | Page : 99-101
An unusual case of bilateral unicystic ameloblastoma in third molar region
Vikram Deshmukh, Raunak Sunil Patwa, Prachi Bhanudas Chhindam, Nikhil Joshi
Department of Oral and Maxillofacial Surgery, Sinhgad Dental College and Hospital, Pune, Maharashtra, India
|Date of Web Publication||18-Jun-2015|
Dr. Raunak Sunil Patwa
Raunak, Datta Nagar, New Karad Naka, Pandharpur - 413 304, Maharashtra
Source of Support: Sinhgad Dental College and Hospital., Conflict of Interest: None
Unicystic ameloblastoma (UA) is less encountered variant which is believed to be less aggressive. A rare case of bilateral unicystic mural ameloblastoma in a 24 year old pregnant female is presented which was treated by en-block resection with preservation of the lower border of the mandible. The rationale for this treatment modalitiy and other treatment options for this condition including post resection reconstruction have been discussed in this article.
Keywords: Unicystic ameloblastoma, third molar, segmental mandibulectomy, chemical cauterization, titanium reconstruction plate
|How to cite this article:|
Deshmukh V, Patwa RS, Chhindam PB, Joshi N. An unusual case of bilateral unicystic ameloblastoma in third molar region. J Dent Allied Sci 2014;3:99-101
|How to cite this URL:|
Deshmukh V, Patwa RS, Chhindam PB, Joshi N. An unusual case of bilateral unicystic ameloblastoma in third molar region. J Dent Allied Sci [serial online] 2014 [cited 2020 Jan 25];3:99-101. Available from: http://www.jdas.in/text.asp?2014/3/2/99/159093
| Introduction|| |
Ameloblastomas are benign tumours whose importance lies in its potential to grow into enormous size with resulting bone deformity. They are typically classified as multicystic (solid) and unicystic, central and peripheral, benign and malignant.
The term Unicystic ameloblastoma was first introduced by Robinson and Martinez in 1977 and it is derived from macroscopic and microscopic appearance.  The Unicystic ameloblastoma (UA) is a less encountered variant of the ameloblastoma, referring to those cystic lesions that show clinical and radiographic characteristics of an odontogenic cyst but in histopathological examination shows a typical ameloblastomatus epithelial lining part of the cyst cavity, with or without luminal and/or/ mural tumor proliferation.
We report one such rare case of bilateral UA-mural type associated with impacted mandibular third molars in a 24 year old female patient.
| Case Report|| |
A 24 year old female patient reported to our department with the complaint of pain in right and left back region of lower jaw since one week [Figure 1]. The pain was severe and persistent after the extractions of wisdom teeth of lower jaw by a private dentist 20 days back. The medical history, personal history and the family history were not contributory. Patient was of average build, well-nourished with normal gait and vital signs were within normal limits. There was no obvious facial deformity or swelling in the head and neck region; however mild trismus was present. Intra oral examination revealed the non-healed extraction sockets in relation to 38 and 48. The regional lymph nodes were non-palpable and non-tender. Orthopantomograph (OPG) revealed two well defined unilocular radiolucent lesions (Dia: approx 4 cm) associated with the extraction sockets of 38 and 48 each [Figure 2]. A provisional diagnosis of dentigerous cyst was made and an incisional biopsy was performed under local anesthesia.
Histopathological report revealed UA of mural type on both sides [Figure 3]. In view of high recurrence rate associated with mural type of UA, block resection was planned. Considering the large lesion on right side, extra-oral approach and segmental mandibulectomy was planned. Since the lesion on left side was accessible per oral, an intra-oral resection planned. Meanwhile, patient became aware that she was pregnant. Therefore, surgery was performed in the second trimester under general anesthesia after obtaining consent from her gynecologistAfter the removal of pathological tissue, chemical cauterization was achieved with Carnoy's solution [Figure 4]. Following the resection of the lesion on right side, a titanium reconstruction plate was fixed to avoid pathological fracture [Figure 5]. Histopathological examination of resected lesion confirmed the diagnosis as well as safe margins.
Patient's recovery was uneventful and she is being followed up regularly.
| Discussion|| |
This case report reveals a rare entity of UA which is bilaterally present at the angle of mandible. Same site of tumour location and its association with impacted tooth on both sides makes this case very unique. Bilateral presence of these histologically identical lesions could not be linked to any such case mentioned in English literature so far to the best of our knowledge.
UA is a rare type of ameloblastoma accounting for approximately 6% of all ameloblastoma. ,
The lesion in essence is a well defined cystic sac lined by ameloblastomatous epithelium with or without luminal and or mural proliferation.
Most of UAare associated with impacted teeth and such lesions are referred to as dentigerous variants and those lesions which are not in association with an impacted tooth are called non dentigerous type.  In our case bilaterally the lesion was related to impacted mandibular third molars
The literature suggests that location within jaw bones favours greatly mandible and site of predilection is posterior region of mandible.  It usually occurs in young age group of 16-20yrs. the gender distribution shows a slight male predilection with a male to female ratio of 1.6:1. 
The patient had only pain and no extra-oral swelling which suggests that routine surveillance through regular oral examination and radiographs of impacted teeth are necessary to detect lesions at an early stage.
Ackermann classified this entity into the following three histologic groups: 
Group I Luminal UA (tumor confined to the luminal surface of the cyst)
Group II Intraluminal/plexiform UA (nodular proliferation into the lumen without infiltration of tumor cells into the connective tissue wall)
Group III Mural UA (invasive islands of ameloblastomatous epithelium in the connective tissue wall not involving entire epithelium). According to this classification, our case study belongs to group III.
- Histologic subgroup by Philipsen and Reichart has also been described: 
- Subgroup 1 - Luminal UA
- Subgroup 1.2 - Luminal and intraluminal
- Subgroup 1.2.3 - Luminal, intraluminal and intramural
- Subgroup 1.3 - Luminal and intramural.
Treatment planning depends on histological type of UA. The histological typing of current case was group 3 according to Ackerman et al & subgroup 1.3 as per Phillipsen & Reichart.
After histological assessment as mural type UA en-block resection was planned. This surgical procedure involves resection of diseased section of jaw and inclusion of about 1 cm of apparently uninvolved bone with preservation of the lower border of mandible.
Some authors have suggested conservative surgery as a satisfactory approach to treatment of UA. The conservative surgical techniques include enucleation and chemical cauterization.  Some authors insist radical resection; which in our case was not the choice considering the morbidity associated with the pregnancy and challenge of the post-resection reconstruction of the bilateral continuity defect.
Enucleation although seems to be a rational and objective approach for the management of UA, literature shows occasional recurrences with this procedure. It is also suggested that the vigorous curettage of the bone should be avoided following enucleation as it may implant foci of ameloblastoma more deeply into the bone leading to recurrence. 
| Conclusion|| |
UA is a tumour with a strong propensity of recurrence, especially when the ameloblastic focus penetrates the adjacent tissue. Very rarely, we come across a case with presentation of bilateral UA of mural type. The post-resection reconstruction of the bilateral continuity defect remains a challenge considering the morbidity and complexities. Therefore, the routine surveillance through regular oral examination and radiographs of the impacted teeth are necessary to detect lesions at an early stage.
| References|| |
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[Figure 1], [Figure 2], [Figure 3], [Figure 4], [Figure 5]