A case of granular cell ameloblastoma presenting as a non-healing socket

From Volume 46, Issue 9, October 2019 | Pages 862-864

Authors

Nazanin Ahmadi-Lari

BDS, MFDS RCS(Edin)

Dental Core Trainee 2 in Oral and Maxillofacial Surgery, Bristol Dental Hospital, University Hospitals Bristol NHS Foundation Trust

Articles by Nazanin Ahmadi-Lari

Email Nazanin Ahmadi-Lari

Mark Wilson

MCh, FRCSI(OMFS), MFDS RCSEd

Consultant Oral and Maxillofacial Surgeon, University Hospital Limerick, St Nessan's Road, Dooradoyle, Co Limerick, V94 F858, Ireland

Articles by Mark Wilson

Ceri Hughes

BDS, FDS RCS, MBChB, FRCS(OMFS), FRACDS(OMS)

Specialist Registrar, Department of Oral and Maxillofacial Surgery, Southmead Hospital, Bristol.

Articles by Ceri Hughes

Steven Thomas

BDS(Lond), MB, BCh(Wales), PhD(Q'ld), FDS RCS, FRCS(Eng), FRCS(OMFF)

Professor and Consultant in Oral and Maxillofacial Surgery, Division of Oral and Maxillofacial Surgery, School of Oral and Dental Science, University of Bristol, Lower Maudlin Street, Bristol, BS1 2LY, UK

Articles by Steven Thomas

Abstract

This case involves a 46-year-old female who was referred to the Bristol Dental Hospital Oral and Maxillofacial Surgery department with a non-healing socket. Investigations were carried out and biopsy confirmed diagnosis of granular cell ameloblastoma. She was subsequently treated with a segmental resection and a bone graft to reconstruct the defect of her mandible.

CPD/Clinical Relevance: This report highlights the significance of taking a full history and carrying out a thorough clinical examination to ensure significant diagnoses are not missed.

Article

Nazanin Ahmadi-Lari

The healing of an extraction socket is generally an uncomplicated process; however, it is not an uncommon finding for delayed healing to take place. Clinicians are faced with this post-operative complication in both primary and secondary care settings. In the majority of cases of delayed healing from extraction sockets, it is local factors which dominate, such as clot disintegration, secondary infection or foreign bodies within the socket.1 However, other lesions which may complicate healing can be overlooked and underestimated owing to their rare occurrence. Failure of the alveolus to heal post exodontia in the absence of any medical or dental pathology is a feature which should raise the index of suspicion for other differential diagnoses to be considered, including a possible intra-oral neoplastic tumour.2

Odontogenic tumours encompass a group of lesions of variable clinical behaviour and histopathology.3 Of all swellings within the oral cavity, 9% are odontogenic tumours and, within this group, ameloblastoma accounts for 1% of them.3 Ameloblastoma is a slow-growing odontogenic tumour of the jaw often presenting in the second decade of life.4 There are different histopathological variants of ameloblastoma, of which plexiform and follicular subtypes are more common.5 A rare subtype of ameloblastoma which has been reported as being more aggressive is the granular cell subtype, and this accounts for less than 5% of cases.6 If left untreated, it can cause severe facial abnormalities and consequently have significant impact on patients' lives.

The following is a case report of a patient, diagnosed with granular cell ameloblastoma, who initially presented to us with a non-healing extraction socket.

Case report

A medically fit 46-year-old female was referred to the Oral and Maxillofacial Surgery department with a non-healing socket from the lower right second molar (LR7). On clinical examination, there was no regional or cervical lymphadenopathy, nor any evidence of buccal or lingual expansion, and all cranial nerves were intact. Intra-oral examination revealed a non-healing socket from the LR7 which had granulation tissue filling a small distinct cavity.

Further investigations were carried out, which included an orthopantomograph (OPT) (Figure 1). This revealed a large, multilocular radiolucency with poorly-defined borders, located in the posterior body of the right mandible, extending distal to the lower right first molar. At this presentation, differential diagnoses included an odontogenic keratocyst, an aneurysmal bone cyst or a squamous cell carcinoma. These can all present as similar characteristics on an OPT. The non-healing extraction socket was surgically explored, and an incisional biopsy confirmed diagnosis of granular cell ameloblastoma.

Figure 1. OPT radiograph showing a multilocular radiolucency in the right body of the mandible.

Computed tomography (CT) scanning revealed a lytic lesion within the body of the right mandible measuring 24 x 19 x 20 mm and destruction of the inner cortex of the mandible. A 3D model of the patient's jaw was constructed, and this showed the ameloblastoma came within 12 mm of the lower border of the mandible. In order to excise the tumour completely and minimize the risk of recurrence, a resection margin of 1 cm was undertaken, and the patient was subsequently treated with a hemi-mandibulectomy and an iliac crest, non-vascularized bone graft was used to reconstruct the continuity defect of her mandible (Figure 2).

Figure 2. Post-operative OPT radiograph showing reconstruction of the mandible.

Discussion

Ameloblastoma is a slow growing, locally aggressive, benign tumour which, in this case, presented as a non-healing socket. However, this is a less common manifestation of ameloblastoma and, therefore, this case report highlights the significance of a thorough clinical examination, early detection and prompt referral of suspicious lesions. General dental practitioners (GDPs) are a fundamental part of the management team and it is likely that they will be the first point of contact for patients who experience delayed healing after an extraction. The GDP needs to be aware of differential diagnoses and should initially exclude common, innocuous causes of delayed healing. This includes alveolar osteitis (dry socket), which usually takes place 3–4 days after an extraction. The risk of experiencing this post-operative complication increases if the patient is a smoker and also if the extraction is more complicated.7,8

Other common causes of delayed healing include secondary infection due to foreign bodies, such as suture material or socket dressings.9 Once these causes have been excluded, and there are still persistent clinical signs and symptoms, this should raise suspicion and referral to secondary care is advised.

Further differential diagnoses which may require additional investigations include the possibility of a residual cyst.10 This results from persistent chronic periapical pathology after a tooth has been extracted and may present as an incidental finding on a radiograph. The patient may also develop a chronic infection which manifests as osteomyelitis or osteonecrosis.11 Osteonecrosis is an area of exposed, necrotic bone which has been persistent for 8 weeks and is seen more with patients who have previously had radiation therapy to the head and neck region, or if they have previously taken or currently take medications such as bisphosphonates.12,13 This emphasizes the importance of GDPs being vigilant in their medical history-taking, to ensure that they are fully aware of possible post-operative complications when presented with a non-healing socket.

Conclusion

Given that neoplastic lesions are relatively rare, it is therefore all the more important for GDPs to remain mindful of the diagnostic red flags that may raise suspicion to ensure that appropriate referral pathways are established. A thorough history, with emphasis on a comprehensive medical history and social history, should be taken. A detailed and systematic approach should be taken whilst carrying out clinical examination of the regional neck lymph nodes, the oral cavity, as well as the lesion in question itself. Early diagnosis is of paramount importance for improving long-term prognosis and outcome for patients.