Mandibular Florid Cemento-Osseous Dysplasia: A Case Report

Background: Florid cemento-osseous dysplasia (FCOD) is a non-neoplastic lesion involving multiple quadrants of the jaw. Case presentation: Patients are usually asymptomatic, and the diagnosis mainly depends on radiographic and clinical examinations. Here, we describe a 50-year-old female patient with clinical manifestations of bone defect, no pain or swelling, combined with imaging indicators of secondary infection. However, there are no accepted treatment guidelines for complex FCOD. Conclusions: Therefore, based on a review of the literature, this article describes treatment approaches for symptomatic patients and details the successful treatment of FCOD with superimposed fungal osteomyelitis.


Background
The term orid cemento-osseous dysplasia (FCOD) refers to a group of bro-osseous (cemental) exuberant lesions with multi-quadrant involvement 1 . Melrose et al rst described the disease in 1976; however, its pathogenesis remains unclear 2 . These lesions are also known as sclerosing osteitis, multiple ossi cation, diffuse chronic osteomyelitis, and giant resistant bone cementoma. In 2005, the World Health Organization divided Cemento-Osseous Dysplasias (CODs) into three types: periapical, focal, and orid 3 . These three diseases are di cult to distinguish clinically, and accurate diagnosis mainly depends on histological and radiographic examinations. Although COD may be completely asymptomatic, some patients have pain, swelling, and purulent secretion 4 .
It is generally assumed that COD arises from the periodontal ligament, because of the physical proximity and histopathologic similarity 5 . The clinicopathologic features of COD are as follows: (1) the disease mainly occurs in black middle-aged women; (2) lesions are limited to the jaw and can involve multiple quadrants; (3) mandibular involvement is much more common than maxillary involvement; (4) pathological ndings are similar to calci ed foci of bone cement with broblast matrix1 5-7 . However, the incidence of COD is unknown as a great number of patients are asymptomatic and the disease tends to be noted incidentally on routine radiographic examinations 8 . Symptoms such as dull pain, swelling, and purulent discharge are almost always associated with secondary infection 6,7,9 . Given the rarity of FCOD, there are currently no formal treatment guidelines. Retrospective studies over the last decade have indicated that, for asymptomatic patients, invasive surgery should be avoided. Invasive surgery may result in poor healing and increased infection in FCOD-affected lesion areas. For symptomatic patients, there is still considerable controversy as to the optimal treatment for this disease.

Case Presentation
The patient, 50 years old, was admitted to Department of Oral and Maxillofacial Oncology, Wuhan University. Two weeks ago, a "cyst" was found in her right mandible after a routine dental radiograph at the local hospital. The maxillofacial examination revealed facial symmetry; the range and track of mandibular movements were normal. I guarantee that the study is conducted in accordance with international, national and institutional rules, taking into account the right to know of patients in clinical studies. Approved by the Ethics Committee of Huazhong University of Science and Technology. Oral examination showed dentition defects and a removable partial denture. The remaining teeth had caries to varying degrees. An intraoral examination revealed a lack of fullness in the lingual alveolar bone of the right mandible, with normal mucosa and no pain on palpation. Curved tomography showed radial lesions of the mandible involving 44 ~ 46 and 36 ~ 38 spines, as well as in the maxillary region. To better evaluate the lesion, we performed jaw cone-beam computed tomography which showed multiple perforations of the buccal cortex plate (Fig. 1).
The operation was performed under general anesthesia and the intraoral path was selected. Cut along the gingival margin of the mandibular region 0.5 cm, separate and turn the gingival mucoperiosteal ap to the lesion jaw area. Scrape off the wall tissue and close the wound. After operation, anti-infection treatment was given. Seven days following treatment, the patient had recovered well with no allergies or signs of infection. Pathological sections showed typical fungal infection (Fig. 2). The patient was followed up after 1, 3, 5, 7, 12, and 24 months and surface tomography at each follow-up showed good bone regeneration in the original lesion area.

Discussion And Conclusion
Florid cemento-osseous dysplasia is a rare benign lesion that can involve periapical and alveolar areas; it is characterized by variable radiologic features in multiple quadrants of the jaw. To date, there is little research on this disease and the available studies are primarily small case report In particular, for symptomatic patients, there are currently no accepted treatment guidelines. Further, the available studies are mostly retrospective; there is a lack of control and prospective research. Nonetheless, we have summarized the available treatment strategies that have been shown to be feasible in the small number of available case reports.
We reviewed 43 con rmed cases from 2009 to 2020 and found that 36 of them were female with a median age of 44 years (range 18-72 years) (Table 1); this is consistent with the characteristics of FCOD reported by MacDonald-Jankowski et al. Half of the patients identi ed in our review had no clinical features, and most of the X lines showed opaque masses (90%). The proportions of patients with pain, swelling, or purulent secretion, were 44%, 33% and 9%, respectively.
Other symptoms such as sensory abnormalities and dilation were also been reported in some cases. Imaging examination combined with clinical characterization plays a vital role in FCOD diagnosis. Based on imaging features, FCOD can be divided into three stages: (1) the lesion is dominated by radiolucent changes, showing destructive osteolytic changes; (2) the lesion is characterized by mixed radiologic/intransparent changes; (3) the lesion is characterized by an opaque mass, a "sclerotic or inactive" stage. With regard to the above case study, we found multiple radiated opaque masses around the apex and the radiated opaque halo was limited to the dental region. However, cortical perforation is often associated with bone tissue infection. Therefore, we can reasonably assume that this patient's unusual bone breakdown was due to secondary infection. The presence of new bone formation or a periosteal reaction is key to distinguishing between fungal and suppurative osteomyelitis; thus, we excluded the possibility of suppurative infection.
According to current treatment guidelines, FCOD patients should avoid any invasive surgery. However, for asymptomatic patients who need to recover masticatory function, routine treatment is not enough. The retrospective review of the literature revealed that resection or curettage of lesions for symptomatic FCOD is the most common surgical treatment. However, the resection range should be carefully selected to obtain a balance between functional recovery and prevention of recurrence. Although the disease is histologically benign, multiple relapses are reported in some cases. When there are no invasive imaging ndings, only lesions that cause clinical symptoms should be removed. Active surgical intervention is required when associated with fungal osteomyelitis. For patients with uncomplicated fungal infections, systemic antifungal agents such as amphotericin B, voriconazole, itraconazole, and caspofungin can be used exclusively. However, when these infections are secondary to FCOD, the response to systemic antifungal antibiotics is weak due to altered vascular properties in the lesion area. Hence, complex FCOD requires surgical debridement and remova. For some invasive cases, in situ treatment is performed with aggressive benign tumors or carcinoma; however, this will leave a severe dentition defect.
Florid cemento-osseous dysplasia is a benign, nonneoplastic, self-limiting disease. Few cases have been reported in the current literature. FCOD often presents with no symptoms and is found incidentally on radiographs. In asymptomatic individuals, conservative approaches, such as broad-spectrum antibiotics in the case of infections along with surgical debridement and enucleation, are required. In asymptomatic individuals, only periodic follow-up and good oral care are advised.

Cemento-Osseous Dysplasias (CODs)
Declarations Ethics approval and consent to participate The case report was reported with the informed consent of the patient.

Consent for publication
The images in the manuscript had been given the informed consent of the patient.

Availability of data and materials
The datasets used and/or analysed during the current study are available from the corresponding author on reasonable request.

Competing interests
The authors declare that they have no competing interests.

Funding
Not applicable.

Authors' contributions
Author Zirong Tang: Contributed to conception, design, acquisition, drafted manuscript, critically revised manuscript, gave nal approval and agree to be accountable for all aspects of work ensuring integrity and accuracy.
Author Lin Wang: Contributed to conception, design, acquisition, drafted manuscript, critically revised manuscript, gave nal approval and agree to be accountable for all aspects of work ensuring integrity and accuracy.
Author Ming Yang: Contributed to conception, design, acquisition, drafted manuscript, critically revised manuscript, gave nal approval and agree to be accountable for all aspects of work ensuring integrity and accuracy.
Author Yulin Jia: Contributed to design, acquisition, analysis, and interpretation ,drafted manuscript, critically revised manuscript, gave nal approval and agree to be accountable for all aspects of work ensuring integrity and accuracy.All authors gave their nal approval and agree to be accountable for all aspects of the work. 2. MacDonald-Jankowski DS. Fibro-osseous lesions of the face and jaws. Clin Radiol. 2004;59:11-25. doi:10.1016/j.crad.2003 Figure 1 Imaging examination of the patient.

Figure 2
Pathological sections of the patient.