Cemento-osseous dysplasia (COD) is an uncommon, non-neoplastic benign fibro-osseous lesion of the jaws, characterized by cementum-like tissue deposition. It primarily affects middle-aged women of African and East Asian descent. Generally asymptomatic, this condition is frequently identified incidentally through radiographs showing radiopacities with radiolucent rims. This report presented a case of florid cemento-osseous dysplasia (FLCOD) in a 45-year-old Asian female. The patient exhibited secondary caries extending to the pulp chamber on the left mandibular first molar, showed no signs of pulpitis or periapical pathosis. Adjacent tooth (the left mandibular third molar) and contralateral molars (the right mandibular molars) responded normally to pulp vitality testing, with no swelling, sinus tracts, or mobility observed. Cone beam computed tomography (CBCT) revealed multifocal lesions with amorphous radiopacities and thin radiolucent rims without root resorption or cortical perforation in the periapical regions of bilateral mandibular molars. These findings reflected characteristic radiographic features of FLCOD, aligning with the World Health Organization (WHO) 2022 classification criteria. Significantly, three radiographic stages of COD were concurrently demonstrated through multifocal lesions involving six mandibular molars, providing a representative model of its natural progression. The initial osteolytic stage in teeth 38, 46, and 48 manifested as well-defined periapical radiolucencies with sclerotic borders; the intermediate stage in 36 and 37 featured punctate or nodular radiopacities within periapical radiolucency; while the mature terminal stage in 47 presented a homogeneous radiopaque mass bordered by a thin radiolucent rim. The diagnostic process prioritized exclusion of chronic apical periodontitis through confirmed pulp vitality and absence of infection. Cemento-ossifying fibroma (COsF) was dismissed based on solitary presentation and cortical expansion. Familial gigantiform cementoma (FGC) was differentiated by early diffuse jaw expansion and extensive involvement beyond COD. Cementoblastoma exclusion relied on pathognomonic features, specifically root resorption or compromised pulp vitality. Given the asymptomatic, non-progressive behavior of the FLCOD lesions, annual surveillance was implemented, with intervention limited to the restorative failure in tooth 36. At 12-month follow-up, the FLCOD lesions showed clinical-radiographic stability without secondary infection or progression. This case reflected the classic presentation of FLCOD as incidental, multifocal mandibular posterior radiopacities bordered by radiolucent rims. CBCT proved instrumental in delineating the lesions, providing diagnostic evidence. Long-term surveillance remains the cornerstone of management for COD. Invasive procedures are not recommended in cases with asymptomatic non-progressive behavior to prevent surgical complications. 牙骨质-骨结构不良(cemento-osseous dysplasia, COD)属于临床少见的一种纤维-骨肿瘤及结构不良, 病变通常无症状, 多通过X线检查偶然发现。本文报道1例就诊于北京大学国际医院口腔科的45岁女性繁茂型牙骨质-骨结构不良(florid cemento-osseous dysplasia, FLCOD)病例, 患者因左下后牙充填体脱落3周就诊, 临床检查发现左下颌第一磨牙(36)存在继发龋坏达髓腔, 但无牙髓炎或根尖周病症状。邻近牙齿(左下颌第三磨牙)及对侧磨牙(右下颌第一、二、三磨牙)牙髓活力测试反应正常, 无肿胀、窦道或牙齿松动。锥形束CT(cone beam computed tomography, CBCT)检查显示, 双侧下颌磨牙根尖周区域存在多灶性混合密度病变, 符合世界卫生组织制定的FLCOD诊断标准。病变累及的6颗牙齿(36、37、38、46、47和48)根尖周影像学表现多样, 呈现骨质溶解破坏期、类牙骨质小体形成期与钙化成熟期三期并存的特征。本病例为临床少见的FLCOD病例, 诊断主要依据其无临床症状的病程、牙髓状态及典型的影像学表现。CBCT在清晰显示病变、提供诊断依据方面发挥了关键作用。治疗策略上应着重处理患者的继发龋等伴发病变, 控制局部与全身风险因素, 而非针对COD病变本身进行干预, 预后还需长期随访。

家族性繁茂性牙骨质-骨结构不良（FFCOD）是累及颌骨两个及以上象限的非肿瘤性的纤维-骨组织病变。ANO5是FFCOD的致病基因。目前国内外关于FFCOD的遗传学研究报道较少。本文报道1例FFCOD患者及基因检测结果，并结合相关文献进行讨论。全外显子组测序发现患者携带ANO5新突变c.G1747A（p.V583I），该位点氨基酸在不同物种间高度保守。本研究拓展了ANO5基因的突变谱，为FFCOD的临床诊疗及遗传咨询提供了参考。.

Despite rare reports of hybrid tumors containing cemento-ossifying fibroma (COF), its association with florid cemento-osseous dysplasia (FCOD) is very rare. A 38-year-old female presented for treatment of an expansive, tumoral lesion extending from the right mandibular lateral incisor to the first molar. Clinical examination revealed a significant bulging of the vestibular and lingual mandible cortices. CT scans revealed a hypodense, unilocular lesion that was relatively well-demarcated. Also, multiple mixed hyperdense/hypodense lesions were observed in the alveolar process of the jaws. An incisional biopsy was performed, and the microscopic features, together with the clinic-radiologic evaluation, were consistent with the diagnosis of COF. The tumor was resected, and the histopathological analysis confirmed the diagnosis. In continuity with the tumor, trabeculae of osteocementoid material were observed, which were likely related to the FCOD noted in the CT scan. Clinical, surgical, radiologic, and microscopic features supported the final diagnosis of a hybrid lesion, exhibiting characteristics of both COF associated with FCOD. There are no signs of recurrence after two years of follow-up.

To date, genetic studies on florid cemento-osseous dysplasia (FCOD) remain limited. This study aimed to elucidate the clinical features and genetic basis of FCOD in Chinese populations, with particular emphasis on identifying pathogenic ANO5 variants and their mechanistic contributions to disease development. Clinical data from 17 FCOD patients diagnosed between May 2015 and December 2024 at Kunming Medical University Affiliated Stomatological Hospital were retrospectively analyzed. Whole-exome sequencing was performed on a familial cohort (8 individuals). Identified variants were validated using Sanger sequencing. Pathogenicity was predicted via SIFT, PolyPhen-2, and MutationTaster, while protein structural alterations were modeled with AlphaFold 2. Histological assessment included H&E staining, Masson trichrome, RUNX2 immunohistochemistry, and TRAP staining to quantify osteoclastic activity. Among the 17 FCOD patients included in this study, 10 (58.8%) were female, with a mean age of 47.4 ± 13.2 years. Genetic analysis identified Anoctamin 5 (ANO5) variants in five cases, including a novel variant (p.I616F). Pedigree analysis confirmed that p.I616F was a heterozygous variant, and bioinformatics prediction indicated its likely pathogenicity. Structural modeling further demonstrated that this variant disrupted the α-helix of ANO5 and altered the catalytic site’s conformation. Additionally, histological evaluation revealed significantly elevated RUNX2 expression and increased osteoclast activity in the jawbone tissues of FCOD patients. This study provides the first evidence that ANO5 variants (particularly p.I616F) may represent key genetic factors contributing to FCOD development in the Chinese population. The mutation likely disrupts the α-helical structure of ANO5 protein, impairing its catalytic function and potentially dysregulating bone remodeling processes in FCOD pathogenesis. The online version contains supplementary material available at 10.1186/s12903-025-06717-5.

The objectives of this study were to better understand the association between simple bone cysts (SBC) diagnosed within florid cemento-osseous dysplasia (FCOD) by systematically reviewing the literature with a meta-analysis. This review allows us to study the epidemiology, characteristics, treatments, and follow-up of the association between these two entities. A systematic review was performed on PubMed, Scopus, Cochrane library, Embase and Google Scholar. Articles reporting primary studies, case reports and case series were included. We reviewed all articles between 1976 and November 2024. Recorded data were patient's characteristics, clinical and radiological features, diagnosis, treatment, and follow-up. The meta-analysis was performed for the prevalence of the localization of SBC associated FCOD and the number of SBC lesions within FCOD. A total of 615 studies were assessed for eligibility by reading titles and abstracts. Finally, 16 articles were included, with 51 patients presenting SBC associated with FCOD. Patients were mostly women (92%) with most of an African origin (81,25% ). The mean age was 41-year-old. The usual treatment for the cyst was surgical exploration with bleeding stimulation to improve healing. After surgical procedure, a majority of the followed-up cases healed completely (52%) or partially (32%). Eight cases reported a recurrence during the mean follow-up period of 6,6 years. SBC and FCOD are two conditions which can be rarely associated. This may be under-diagnosed as SBC can be misdiagnosed as part of the FCOD lesions. This review highlights the similar clinical characteristics to FCOD which makes important to find out more clinical and radiographic diagnosis criteria to better diagnose and provide the adequate treatment to obtain bone healing.