Comprehensive Management of Odontogenic Myxofibroma in the Mandible: A Four-Year Follow-Up Case Report with a Review of Differential Diagnosis and Treatment Approaches

Abstract

Odontogenic myxofibroma (OMF) is a rare, benign, and slow-growing tumour arising from odontogenic ectomesenchyme. Despite its low prevalence, accounting for approximately 0.5% to 17.7% of all odontogenic tumours worldwide and 3.1% in specific regional studies, it poses significant challenges due to its potential for local recurrence if inadequately excised. This case report presents the clinical course, surgical management, and follow-up of a 35-year-old female patient diagnosed with OMF in the mandibular body region. The patient presented with an osteolytic lesion between the first and second mandibular molars, as confirmed through CT imaging, with dimensions of 31 × 22 × 24 mm. Histopathological examination following excisional biopsy under general anaesthesia confirmed the diagnosis of OMF. The surgical procedure involved mandibular segment resection and reconstruction using an iliac crest bone graft stabilised with plates. Subsequent implantation procedures in 2021 restored dental function, and a four-year follow-up demonstrated excellent outcomes, with no signs of recurrence, periimplantitis, or bone graft compromise. This case highlights the importance of comprehensive imaging, histopathological confirmation, and long-term monitoring in managing odontogenic myxofibroma. Early detection and appropriate surgical intervention significantly improve patient outcomes and quality of life.

1. Introduction

Odontogenic tumours (OTs) are rare lesions arising from tooth-forming tissues, originally within the maxillofacial complex. Including less than 1% of head and neck tumours, they range from benign hamartomatous growth to occasional malignant forms. Their prevalence differs across populations due to geographic, genetic, and environmental factors [1].

Odontogenic myxofibroma (OMF) is a rare, benign tumour originating from the odontogenic ectomesenchyme. It is characterised by slow growth but locally aggressive behaviour, with a tendency for recurrence if inadequately excised. Accounting for approximately 0.07 new cases per million annually, OMF primarily affects individuals between 10 and 40 years old, with a slight predilection for females [2,3,4]. Mandibular involvement is most common, though maxillary lesions may lead to extensive destruction and invasion of adjacent anatomical structures [4,5]. Radiographic presentation of odontogenic fibromyxoma is not typical, and this can lead to an incorrect clinical diagnosis. It may vary from small unilocular radiolucent lesions to large multilocular radiolucent lesions which have mostly well-defined borders. Multilocular radiolucent images may resemble a honeycomb, soap bubble, or tennis racket, or may appear wispy or similar to a spider web [6]. Histologically, this condition comprises intercellular mucopolysaccharides, fibroblasts, and myofibroblasts, complicating differential diagnosis with other odontogenic tumours [7].

Therapeutic strategies for OMF range from conservative enucleation to radical surgical resection with safety margins, as recurrence rates can reach 25% with conservative treatment [8]. Reconstruction following radical excision often involves autogenous bone grafts, which enable both aesthetic and functional rehabilitation, including the use of dental implants [9].

In Poland, while specific data on odontogenic myxofibroma are scarce, oral tumours, in general, demonstrate an increasing prevalence, necessitating awareness of rare neoplasms like OMF [10]. This case report presents the comprehensive management of mandibular OMF, focusing on surgical, reconstructive, and restorative approaches, along with a long-term follow-up emphasising the importance of multidisciplinary care for optimal outcomes.

2. Case Report

2.1. Examination

A 35-year-old female patient was referred to the hospital following the detection of a bony defect on the right side of the mandible, identified on a panoramic radiograph (OPG) (Figure 1). The patient noticed the increasing and painless swelling in the oral cavity over the course of a month and contacted their dentist. Conservative treatment was performed on tooth 46, resulting in a temporary swelling reduction. Two months later, the swelling rapidly recurred over two days. After obtaining an OPG X-ray, the patient was referred to the maxillofacial surgery department. The OPG revealed a lesion in the right mandibular body, without root resorption, with displacement of the roots of teeth 45 and 46 (Figure 1).

The patient exhibited facial asymmetry on the right side. Extraoral examination revealed normal skin colour and temperature, normal sensation, normal mouth opening, and no lymphadenopathy. The overall oral and dental health appeared satisfactory upon inspection. Intraoral examination showed normal periodontium and mucosa without any sign of inflammation. On clinical examination, there was a palpable hard swelling on the buccal side of the mandibular posterior teeth 44–47. Lower teeth showed a normal response to vitality tests. Tooth 46 showed caries-induced destruction, partial resorption, and mobility.

The patient’s medical history was unremarkable, with no known diseases, drug allergies, or history of jaw trauma. She reported no symptoms such as pain or hypoesthesia.

CT examination of the craniofacial region performed before and after contrast agent administration demonstrated an expansively growing osteolytic lesion in the right mandibular body between teeth 46 and 47. The lesion measured 31 mm in anteroposterior length, 22 mm in width, and 24 mm in height. The lesion involved the root of tooth 46 and partially tooth 47, extending up to tooth 44, and for that reason, the resective surgery extended up to tooth 42. It caused mandibular expansion with thinning of the cortical layer and caused disruption over a length of approximately 7 mm on the internal aspect. The lesion exhibited slight post-contrast enhancement. The CBCT (cone-beam computed tomography) examination is presented in Figure 2 and a 3D reconstruction is presented in Figure 3.

2.2. Treatment Procedures and Histopathological Results

Under local anaesthesia, tooth 46 was extracted in July 2020, and a tissue sample was collected for histopathological examination. The buccal cortical plate of the alveolar process was destroyed, and panoramic radiography was performed (Figure 4). The histopathological analysis identified the lesion as OMF. Fragmentary material prevented confirmation of surgical margins, and the lesion was classified as D37 (a neoplasm of uncertain or unknown oral nature). Postoperative recovery was without complications, with minor swelling at the surgical site. Microscopic examination of the tissue (H and E staining) revealed a tumour mass composed of a loose, myxoid matrix with a delicate network of collagen fibres, exhibiting a characteristic myxofibroma appearance. Additionally, spindle-shaped cells were observed, scattered evenly throughout the stroma, displaying minimal atypia (Figure 5). Based on these findings, a histopathological diagnosis of OMF was established.

In September 2020, the patient underwent segmental resection and grafting of the iliac cancellous bone under general anaesthesia. A right submandibular incision was made, and the diseased mandibular body was exposed from the incisor region to the mandibular angle. The mandibular body was resected, with additional excision of the anterior margin of the stump. Additionally, a fragment of the stump was excised as the anterior margin. Muscle tissue from the oral cavity floor adjacent to the diseased lingual surface of the mandibular body was collected. Haemostasis was achieved.

A bone block measuring 6 × 3 cm was harvested from the right iliac crest, and the surface of the iliac bone was secured with surgical wax. The block was carefully fitted to the mandibular defect and stabilised using four plates of the 2.0 system. Layered suturing of the wounds was performed, leaving Redon drains in place. The resected mandible was sent for histopathological examination.

Histopathological examination of the excised lesion, stained with H and E, revealed a loose, myxoid stroma. The collagen fibres exhibited an irregular distribution, interspersed within the myxoid matrix. Some areas demonstrated increased collagen density, resembling fibrous tissue. Spindle-shaped fibroblasts were observed throughout the mucinous stroma. The nuclei appeared small, oval, or elongated, with irregular orientation within the matrix. Additionally, two distinct hyperchromatic areas were identified, corresponding to residual bone fragments (Figure 6). The result confirmed odontogenic myxofibroma. Surgical margins were carefully evaluated during resection due to the high recurrence rate (about 25%) associated with incomplete excision.

2.3. Postoperative Care

Postoperative care contained the administration of appropriate medications to control pain, prevent infections and promote recovery. This included antibiotics (amoxicillin with clavulanic acid), analgesics (metamizole and paracetamol), antiemetics (ondansetron), and a proton pump inhibitor (pantoprazole). Anticoagulant treatment with enoxaparin was also administered subcutaneously to prevent thrombotic events.

There were no postoperative complications. The patient remains symptom-free, and the most recent OPG X-ray shows a bony infill (Figure 7).

2.4. Follow-Ups

The first follow-up panoramic X-ray was taken 4 months after the procedure, and is shown in Figure 8.

In April 2021, MIS Dentsply Sirona dental implants were placed as follows: tooth 46—4.20 × 10 mm, tooth 47—3.75 × 13 mm, and tooth 44—3.75 × 11.50 mm, to restore function. Regular follow-up examinations were conducted to monitor for recurrence or complications (Figure 9).

At the four-year follow-up examination in November 2024, panoramic radiography (Figure 10), along with intraoral and extraoral evaluations (Figure 11), showed no signs of recurrence, peri-implantitis, or bone resorption. The bone graft demonstrated good osteointegration, and the patient reported high satisfaction with both the functional and aesthetic outcomes. However, the patient reports persistent sensory disturbances, including loss of cutaneous sensation and vestibular mucosal sensitivity in the affected region.

3. Discussion

3.1. Diagnostic Features with Differential Diagnoses

OMF is a rare, benign tumour characterised by its odontogenic ectomesenchymal origin and slow, infiltrative growth. It shows a slight predilection for females, which aligns with the presented case. In contrast, other lesions such as ameloblastoma, chondromyxoid fibroma, and osteosarcoma tend to demonstrate either equal distribution or male predominance [2,11].

Radiographically, OMF often presents as a multilocular radiolucency with “soap-bubble” or “honeycomb” patterns. These characteristics, however, overlap with other conditions, such as ameloblastoma and chondromyxoid fibroma, making differentiation challenging [4,12]. Histologically, OMF is defined by spindle and stellate-shaped cells within a myxoid stroma with prominent collagen fibres, which help differentiate it from odontogenic myxoma [4,13]. Additionally, remnants of the odontogenic epithelium may occasionally be seen, further confirming its odontogenic origin [13]. Diagnostic features are summarised in

Table 1. Diagnostic features of odontogenic myxofibroma (OMF).

Aspect	Details	References
Radiographic	“Soap-bubble”, “ground-glass” or “tennis racquet strings” patterns complicating the diagnosis	[4,12,14]
Histology and Odontogenic Epithelium	Spindle and stellate-shaped cells in a myxoid stroma with prominent collagen fibres. Possible remnants of odontogenic epithelium, aiding differentiation from odontogenic myxoma	[4,13,14]
Recurrence Potential	High due to local invasion into cancellous bone and absence of encapsulation	[2,14]

.

Key differential diagnoses include the following:

• Ameloblastoma: Features islands of odontogenic epithelium resembling the enamel organ.
• Chondromyxoid fibroma: Comprises lobules of chondroid and myxoid tissue with spindle cells, commonly affecting long bones.
• Osteosarcoma: Defined by the production of malignant osteoid by atypical osteoblasts and a characteristic “sunburst” radiographic pattern [11].

While the overlapping features necessitate histopathological examination for definitive diagnosis, the absence of a capsule and local invasion into adjacent bone in OMF further complicates its distinction from other aggressive lesions [2,14].

A detailed comparison of the clinical, radiographic, and histopathologic features, treatment modalities, and recurrence rates for ameloblastoma, chondrosarcoma, low-grade mucinous fibrosarcoma, and osteosarcoma is provided in

Table 2. Differential diagnoses for odontogenic myxofibroma comparing clinical, radiographic, and histopathological features, treatment approaches, and recurrence rates for ameloblastoma, chondromyxoid fibroma, low-grade myxofibrosarcoma, and osteosarcoma.

Feature	Odontogenic Myxofibroma (OMF)	Ameloblastoma	Chondromyxoid Fibroma	Low-Grade Myxofibrosarcoma	Osteosarcoma
ICD-O Code	9262/0 (odontogenic myxoma)	9310/0 (benign ameloblastoma)	9240/0 (benign chondromyxoid fibroma)	8830/3 (myxofibrosarcoma, malignant)	9180/3 (malignant osteosarcoma)
Age Group	20s to 40s	30s to 60s	Adolescents and young adults	Middle-aged to older adults	Adolescents and young adults
Gender Predilection	Slight female predominance	Equal distribution	Slight male predominance	Slight male predominance	Slight male predominance
Common Location	Mandible	Mandible	Long bones; rare in jaws	Extremities; rare in jaws	Metaphysis of long bones; jaw involvement rare
Clinical Presentation	Painless swelling, facial asymmetry	Painless swelling, possible ulceration	Localised pain, swelling	Slow-growing mass, may be painless	Painful swelling, rapid growth
Radiographic Appearance	Multilocular radiolucency with “soap-bubble” or “honeycomb” pattern	Multilocular radiolucency, “soap-bubble” appearance	Eccentric, radiolucent lesion with cortical expansion	Ill-defined margins, may show soft tissue mass	Mixed radiolucent–radiopaque lesion, “sunburst” pattern
Histopathology	Spindle and stellate cells in myxoid stroma with collagen fibres	Islands of odontogenic epithelium resembling enamel organ	Lobules of chondroid and myxoid tissue with spindle cells	Spindle-shaped cells in myxoid matrix, mild atypia	Malignant osteoid production by atypical osteoblasts
Treatment Approach	Surgical resection with clear margins; recurrence possible with conservative treatment	Surgical resection; high recurrence rate if not completely excised	Curettage or resection; recurrence possible	Wide surgical excision; may require adjuvant therapy	Neoadjuvant chemotherapy followed by surgical resection; poor prognosis if untreated

.

3.2. Management Methods

3.2.1. Conservative Treatment

For smaller OMF lesions, conservative management involving curettage or simple enucleation may be employed. To reduce recurrence risks, some practitioners advocate for peripheral osteotomy to ensure the removal of any microscopic residual tumour tissue [2,14]. However, these approaches are associated with recurrence rates as high as 25%, largely due to the infiltrative nature of the tumour [2,14].

3.2.2. Radical Surgical Resection

Radical resection is the preferred approach for larger or more aggressive lesions. In this case, segmental resection of the mandibular body was performed, extending to the anterior margin and excising infiltrated tissue. Radical excision with a safety margin of 1.5–2 cm minimises the likelihood of recurrence [15,16]. This is especially critical in maxillary lesions, where local recurrence poses significant functional and aesthetic challenges [17].

3.2.3. Reconstruction and Graft Considerations

Table 3. Comparison of reconstruction and graft methods.

Reconstruction Method	Advantages	Limitations
Free vascularised fibula graft (FVFG) [16]	- Long bone length: a segment of up to 20–26 cm can be harvested, allowing reconstruction of large defects, including bilateral involvement; - Flexibility in osteotomies: the rich periosteal blood supply enables multiple osteotomies, facilitating the replication of mandibular curvature; - Skin paddle: a skin paddle enhances flap viability monitoring and aids in soft tissue restoration	- The limited diameter of the fibula in comparison to mandibular height significantly hundred adequate implant rehabilitation due to the resulting increased distance to the occlusal plane
Double-Barrel Fibula Flap (DBFF) [17]	- Restoration of mandibular height: the DBFF addresses vertical discrepancies in the mandible. - Improved aesthetic and functional outcomes: the restoration of the mandibular height leads to better facial contour and a functional alveolar ridge, making it easier to place dental implants. - No need for deferred surgery: unlike onlay bone grafts or fibula distraction, the DBFF does not require additional surgeries for implant placement, offering a more streamlined approach.	- Vascularisation challenges: segmenting the fibula may disrupt blood flow, potentially leading to flap ischemia or failure. - Surgical complexity: the procedure requires precise technique and expertise to avoid complications such as venous thrombosis or damage to the vascular pedicle. - Aesthetic uncertainty: While the DBFF shows promising results for restoring facial aesthetics, the evidence for cosmetic outcomes is still of low certainty, and standardised assessments are needed. - Limited indications: The technique is most suitable for patients with specific mandibular defects, especially those involving the dentate portion, and may not be appropriate for all patients.
Iliac crest free flap [18]	- Shape and size compatibility: its resemblance to the hemimandible makes it ideal for reconstruction. - Bone quality: the flap provides a balance of cortical and cancellous bone, improving osseointegration and primary stability for implants. - Soft tissue volume: ample soft tissue allows for the reconstruction of large defects. - Blood supply: rich vascularisation ensures immediate perfusion and reduces the risk of bone resorption.	- Donor site morbidity: patients may experience haematoma, gait disturbances, or persistent pain. - Soft tissue bulk: excessive bulk may complicate intraoral reconstructions. - Blood supply risks: multiple osteotomies can compromise perfusion, increasing the risk of flap failure.
Patient-specific implants (PSIs) [19]	- PSIs allow for precise restoration of mandibular shape and occlusion due to preoperative planning and 3D modelling. - The use of predesigned and premanufactured implants shortens surgery duration by eliminating intraoperative shaping of plates. - PSIs provide better stability and fixation, reducing the risk of postoperative complications like malocclusion or plate exposure.	- High cost of producing customised implants and conducting virtual surgical planning. - Due to the fact that implant is designed preoperatively, it may not accommodate unforeseen intraoperative anatomical changes.

provides the advantages and disadvantages of available reconstruction and graft methods.

Autogenous iliac crest bone grafts offer reliable structural and aesthetic restoration. However, they have a major limitation: their potential for unpredictable resorption. This risk can be mitigated by ensuring adequate periosteum coverage, which promotes vascularisation and incorporation of the graft [14]. Additionally, delaying dental implant placement by 4–6 months post-grafting allows for better consolidation and revascularisation [17]. Recent studies demonstrate that implant-supported prostheses not only enhance functional outcomes but also reduce bone graft resorption by stimulating the graft under prosthetic load [9,18].

3.3. Outcomes and Recurrence Prevention

The described case highlights the importance of aggressive surgical management and careful reconstruction. The patient’s four-year follow-up demonstrated no evidence of recurrence, peri-implantitis, or graft compromise, underscoring the success of the adopted approach. Multidisciplinary care—combining imaging, histopathology, surgical expertise, and restorative dentistry—played a crucial role in achieving these outcomes [11].

Recurrence in OMF is primarily attributed to incomplete excision and the tumour’s infiltrative growth into cancellous bone. By employing radical resection with clear margins and monitoring long-term healing, the risk of recurrence is significantly reduced [2,4,14]. Moreover, timely dental rehabilitation improves quality of life, as observed in this case, where the patient reported no functional or aesthetic impairments following treatment.

The treatment approach for odontogenic myxofibroma is summarised in

Table 4. The approach to the treatment of odontogenic myxofibroma (OMF).

Treatment Approach	Details	References
Conservative Management	Smaller lesions: Curettage and simple enucleation, possibly with peripheral osteotomy.	[2,14]
Radical Resection	Larger lesions: Segmental resection with 1.5–2 cm osseous margins to minimise recurrence.	[4,15,16]
Reconstruction	Primary mandibular reconstruction with iliac crest bone graft.	[18]
Graft Considerations	Adequate periosteum coverage to promote vascularisation and reduce resorption.	[9]
Dental Rehabilitation	Dental implants and implant-supported prostheses reduce graft resorption and improve outcomes.	[9,18]
Timing for Implants	Delay between the bone graft and implant placement: 4–6 months to ensure graft consolidation and stability.	[9,18]

.

Table 5. Comparison of the current OMF case with recent case reports.

Reference	Age/Gender	Localisation	Treatment	Follow-Up	Recurrence
Current case	35/F	Posterior segment of the mandible	Resection	4 years	No
Thitiyuk et al. [3]	50/M	Anterior segment of the mandible	Enucleation and curettage	1 year	Not reported
Sweeney et al. [12]	59/F	Posterior segment of the maxilla	Enucleation	Not reported	Not reported
Çelebioğlu et al. [6]	29/F	Anterior region of the mandible	Enucleation	3 years	No
Poudel et al. [13]	53/F	Posterior segment of the mandible	Resection	Not reported	Not reported
Siva Prasad Reddy et al. [20]	12/F	Left maxilla	Curettage and enucleation	Not reported	No

compares our OMF case with the selected recent case reports considering demographic, local, and therapeutic factors.

4. Conclusions

The comprehensive management of odontogenic myxofibroma, including thorough preoperative evaluation, radical surgical resection, and meticulous reconstruction, can result in excellent functional and aesthetic outcomes. This case demonstrates that a well-planned surgical approach, combined with autogenous bone grafts and dental implants, can successfully restore both form and function without compromising the patient’s quality of life.

At the four-year follow-up, the patient showed no signs of recurrence or complications, with the reconstructed mandibular structure achieving good osteointegration and stable dental functionality. Importantly, the patient reported no difference in comfort or daily life quality compared to their pre-diagnosis state. These findings emphasise the value of multidisciplinary care and long-term follow-up in ensuring successful outcomes for patients with odontogenic myxofibroma.

This case further underscores the importance of early detection, accurate diagnosis, and prompt intervention in managing rare odontogenic tumours, offering valuable insights for similar clinical scenarios.