Calcifying Odontogenic Cyst of the Oral Cavity: A Clinical Case and Current Updates on the Ethiopathogenesis

Background: The calcifying odontogenic cyst (COC) is a rare pathological entity. It falls into a group of lesions with calcifications that present benign and sometime malignant tumor variants. Case Presentation: In the present study, we report on a case of intraosseous/intrasinusal COC with impacted maxillary canine and dentinoid structures odontoma-like. The clinical, radiographical, histopathological, and molecular characteristics of this pathological entity are discussed in relation also to the problems of differential diagnosis, treatment, and prognosis. Conclusion: The true COC is a rare entity in the oral cavity and represents about less than 1% of all odontogenic lesions. Careful clinical, instrumental and histological analysis must be performed for odontogenic cysts in order to accomplish the correct surgical act and to avoid recurrence.

A Large Calcifying Cystic Odontogenic Tumor Occupying the Maxillary Sinus: A Case Report and Review of Literature

Calcifying cystic odontogenic tumor (CCOT) is an uncommon benign cystic neoplasm of the jaw that develops from the odontogenic epithelium. It is clinically characterized as a painless—slow-growing tumor that affects the maxilla as well as the mandible, and generally occurs in young adults in the third or fourth decade of life. Herein, we present the case of a 16-year-old Japanese boy who showed a CCOT in the maxillary sinus. Panoramic radiography showed a unilocular lesion in the left maxillary sinus. Computed tomography showed an approximately 5-cm well-defined unilocular expansile lesion with multiple radiopaque calcific specks, arising from the left maxillary alveolar ridge. The lesion was surgically removed, under general anesthesia, and the patient was followed up for 3 years after the surgery, and there have not been any signs of recurrence.

A unique case of a calcifying cystic odontogenic tumor

The calcifying odontogenic cyst was first reported by Gorlin et al. in 1962. At that time, it was classified as a cyst related to the odontogenic apparatus, although it was later renamed as a calcifying cystic odontogenic tumor by the WHO calcification in 2005 due to its histological complexity, morphological diversity and aggressive proliferation [2]. Here, we describe a case of a calcifying cystic odontogenic tumor in a 4- year-old boy. The lesion was surgically removed, and the histopathological examination revealed it to be a cystic tumor with ghost cells, a stellate reticulum and small amount of dentinoid tissue in the cystic wall.

Clear-cell variant of calcifying epithelial odontogenic tumor (Pindborg tumor) in the mandible

We present an uncommon case （female patient aged 59 years） of the clear-cell variant of calcifying epithelial odontogenic tumor （CEOT） （also known as Pindborg tumor） in the mandible. The clinical characteristics and probable origins of the clear tumor cells of previously reported cases of clear-cell variant of intraosseous CEOT are also summarized and discussed.

Chronic progression of recurrent orthokeratinized odontogenic cyst into squamous cell carcinoma:A case report

BACKGROUND Orthokeratinized odontogenic cyst (OOC) is a benign odontogenic cyst. It is a variant of the common odontogenic keratocyst (OKC). This case report describes a rare malignant transformation of OOC, with the aim of raising awareness of the malignant potential of OOC and distinguishing it from OKC. CASE SUMMARY In August 2018, a 52-year-old man was referred to the Department of Oral Maxillofacial and Head–Neck Oncology of Wuhan University. The patient presented with severe pain in the left mandible for 2 mo, and had a 5-year history of osteomyelitis and mandibular cyst with three recurrences. His latest diagnosis by pathological examination was OOC of the left mandible with mild-tomoderate local proliferation. However, the cyst showed malignant potential by radiographic examination. We performed partial mandibulectomy and sent the lesion tissue for pathological examination. As expected, the cyst had deteriorated to moderately differentiated squamous cell carcinoma. During postoperative follow-up, the patient went for chemotherapy in September 2018 and successfully completed four cycles. CONCLUSION Surgeons should be more aware of OOC, which is usually benign but can become malignant.

Calretinin Expression in Unicystic Ameloblastoma and Odontogenic Cysts

Background: Unicystic ameloblastoma arises from similar tissues as the odontogenic cysts. It may also arise from the epithelial lining of these cysts. Furthermore, the epithelial lining of unicystic ameloblastoma is variable and may be almost completely nondescript, which may lead to diagnostic confusion with odontogenic cysts. Calretinin is a calcium-binding protein that has been suggested to be a specific immunohistochemical marker for ameloblastic tissues. The aim of this study was to investigate the usefulness of calretinin in the differentiating unicystic ameloblastoma from odontogenic keratocyst, dentigerous cyst and radicular cyst of the jaws. Materials and Methods: Formalin-fixed, paraffin embedded tissue blocks of 23 unicystic ameloblastomas, 6 odontogenic keratocysts, 8 dentigerous cysts and 10 radicular cysts were utilized. Five micrometer thick sections were made from the tissue blocks and mounted on silanized glass slides. Immunohistochemical staining was done using a 1:100 dilution of mouse monoclonal anti-calretinin primary antibodies (Abcam, SA;Clone 1F5H1) and incubating overnight at 4°C. The staining reaction was visualised using diaminobenzidine substrate solution. Stained tissue sections were evaluated for the presence, distribution, and intensity of staining of the immunoreactive cells. Data analysis was done using SPSS version 23. Statistical tests employed were Chi square test and Kruskal-Wallis test. The level of significance was set at 95% (p-value Results: Calretinin expression was seen in 14 (60.9%) cases of unicystic ameloblastoma, 3 (50.0%) cases of odontogenic keratocyst and a lone (12.5%) case of dentigerous cyst. None of the 10 cases of radicular cyst showed positive expression of calretinin. Staining in unicystic ameloblastoma was mostly localized to the superficial layers, whereas in odontogenic keratocyst it involved all layers of the epithelial lining. There was significant association between lesion type and the immunohistochemical expression of calretinin (p = 0.003). There were also significant differences in calretinin immunoreactivity of unicystic ameloblastoma compared to dentigerous cyst and radicular cyst. Conclusion: The findings of this study suggest that calretinin expression could help differentiate unicystic ameloblastoma from dentigerous cyst and radicular cyst, but not from odontogenic keratocyst.

Histopathological Examination and Literature Review of Orthokeratinized Odontogenic Cyst

Background: With transitions in the disease concept of orthokeratinized odontogenic cyst (OOC), the pathogenesis and etiology have not been sufficiently elucidated. Objectives: OOC cases were reclassified and observed to understand the clinico-histopathological characteristics. In addition, literature review of OOC was performed to better organize the pathology. Materials and methods: Subjects with jawbone cysts lined by keratinized stratified squamous epithelium from 2005 to 2018 were reclassified, and clinico-histopathological findings were analyzed. Previous reports of OOC/orthokeratinized-type odontogenic keratocyst (OKC) from 1980 to 2019 were organized. Results: Five cases of OOC were diagnosed, representing 2.1% of odontogenic developmental cysts (total, 239 cases). Mean age was 37.6 years, with a female predominance. The mandibular molar area was the frequent site, and all cysts were solitary. Sixty percent involved an impacted tooth. Mean maximum diameter of the cyst was 2.2 cm. Histopathologically, 4 cases were unilocular, and partial palisading of the basal layer and scattered epithelial islands were observed in 2 cases each and formation of daughter cysts was noted in 3 cases. Previous papers described that most were unilocular and related to impacted teeth. Mean age ranged between 20 and 40 years, and the mandibular molar region was dominant. Recurrence rates were low. Conclusion: OOC shows a different biological attitude to OKC and is closer to dentigerous cyst. Meanwhile, OOC shows a similar histology of epidermoid cysts accompanying the granular layer. We thus surmised that OCC represents an independent concept as an odontogenic developmental cyst.

Extension of Calcifying Epithelial Odontogenic Tumor to the Maxillary Sinus: A Case Report

The calcifying epithelial odontogenic tumor (CEOT) is a rare and benign odontogenic epithelial neoplasm. This tumor accounts for less than 1% of all odontogenic tumors. It normally affects patients between 30 and 50 years old, and it is typically located in the posterior region of the mandible. Involvement of the maxillary sinus has previously been published only in six cases. This report presents a single case of CEOT that invades the maxillary sinus in a 69-year-old male. We performed a left partial maxillectomy and immediate reconstruction of the defect with a temporalis muscle flap. A comprehensive immunohistochemical study was reported. No recurrences have been found after 8 years of follow-up.

Calcifying cystic odontogenic tumour manifesting in the maxillary antrum: Case report

A case is presented of a 15-year-old boy who manifested the calcifying cystic odontogenic tumour (CCOT) in the left maxillary antrum of an unknown duration. In addition, the patient had a high arched palate and multiple impacted teeth of the normal series and supernumerary type including mesiodens as demonstrated in an orthopantomograph.

Microsurgical management of radicular cyst using guided tissue regeneration technique:A case report

BACKGROUND Radicular cyst is a lesion of odontogenic origin that arises from epithelial remains due to periapical periodontitis caused by inflammatory reactions generated at the apex of affected teeth with infected or necrotic pulps.The therapeutic mana gement of radicular cysts is controversial.There is only one case report of enucleation of a radicular cyst managed with microsurgery and apicoectomy,but without the use of the guided tissue regeneration(GTR)technique in the same surgical procedure.The present clinical case describes the management of a radicular cyst with microsurgical approach,performance of an apicoectomy of the tooth associated with the entity,application of GTR technique,use of a resorbable membrane of type I bovine collagen,and bovine xenograft.CASE SUMMARY A 68-year-old patient presented with a radicular cyst from an upper lateral incisor.The microsurgical management used was aimed at enucleating the chemical membrane,performing apicoectomy of the tooth along with careful and precise retrograde filling,and implementing GTR technique using a resorbable collagen membrane and bovine xenograft.The diagnosis of radicular cyst was confirmed using histopathological analysis.The patient underwent follow-up evaluations at 10 and 30 d postoperatively.At 4 months postoperative evaluation,she remained asymptomatic,and radiographs showed significant periapical healing with adequate bone formation.CONCLUSION These results suggest that microsurgical management using the GTR technique with collagen membrane and xenograft,contributes to bone regeneration.

The Odontogenic Jaw Cysts: Analysis of the Clinical Parameters of 669 Cases

目的 :分析、比较三型牙源性颌骨囊肿的临床特点。方法 :收集 2 0年间牙源性角化囊肿 (odontogenickera tocyst ,OKC)、根端囊肿 (radicularcyst,RC)及含牙囊肿 (dentigerouscyst,DC)的临床资料 ,对其性别构成、年龄分布、发病部位及临床表现等进行比较研究。结果 :1)三型颌骨囊肿的男女之比分别为 :OKC 1.6∶1,RC 1.4∶1,DC 4 .1∶1(χ2 检验 ,P <0 .0 0 5 )。 2 )除DC未见于 70岁以上年龄段外 ,几乎各年龄段均见三型颌骨囊肿的发生 ,三型囊肿组间及组内的年龄分布均有显著性差异 (χ2 检验 ,P <0 .0 0 5 )。OKC及RC2 0～ 2 9岁年龄段患病人数最多 ,分别占各年龄段患病人数的 2 7%及 2 0 % ;DC10～ 19岁年龄段患病人数最多 ,占各年龄段患病人数的 2 9%。 3)颌骨的任一部位均见三型颌骨囊肿的发生 ,但发生频率不同 ,三型颌骨囊肿组间及组内发病部位的分布有显著性差异 (χ2 检验 ,P <0 .0 0 5 )。 4 )OKC有 137例合并感染 ,感染率 39% ;RC4 8例合并感染 ,感染率 2 4 % ;DC18例合并感染 ,感染率 16 % ,三型间有显著性差异 (χ2 检验 ,P <0 .0 0 5 )。结论 :1)男性较女性更易发生牙源性颌骨囊肿。 2 )不同的年龄段 ,对OKC、RC及DC的易感性不同。OKC及RC发生的高峰期均为 2 0～ 2 9岁年龄段 ;DC发生的高峰?

Enucleation combined with guided bone regeneration in small and medium-sized odontogenic jaw cysts

BACKGROUND The odontogenic jaw cyst is a cavity containing liquid,semifluid or gaseous components,with the development of the disease.In recent years,with the rapid development of oral materials and the transformation of treatment of jaw cysts,more options are available for treatment of postoperative bone defect of jaw cysts.Guided bone regeneration(GBR)places biomaterials in the bone defect,and then uses biofilm to separate the proliferative soft tissue and the slow-growing bone tissue to maintain the space for bone regeneration,which is widely used in the field of implantology.AIM To observe the clinical effect of GBR in repairing bone defect after enucleation of small and medium-sized odontogenic jaw cysts.METHODS From June 2018 to September 2020,13 patients(7 male,6 female)with odontogenic jaw cysts were treated in the Department of Oral Surgery,Ninth People’s Hospital,Shanghai Jiao Tong University School of Medicine.Adults without hypertension,heart disease,diabetes or other systemic diseases were selected.The diagnosis was based on the final pathological results:11 cases were diagnosed as apical cysts,one as primordial cyst,and one as dentigerous cyst.The lesions were located in the maxilla in seven cases,and in the mandible in six cases.All cases were treated with the same method of enucleation combined with GBR.RESULTS Three to four months after the operation,the boundary between the implant site and the surrounding normal stroma was not obvious in patients with small-sized odontogenic jaw cysts.The patients with tooth defects were treated with implant after 6 mo.For the patients with medium-sized odontogenic jaw cysts,the density of the center of the implant area was close to the normal mass at 6 mo after surgery,and there was a clear boundary between the periphery of the implant area and the normal mass.The boundary between the periphery of the implant area and the normal mass was blurred at 8-9 mo after surgery.Patients with tooth defects were treated with implants at>6 mo after the operation.CONCLUSION Enucleation combined with guided bone regeneration in small and medium-sized odontogenic jaw cysts can shorten the time of osteogenesis,increase the amount of new bone formation,reduce complications,and improve quality of life.

Efficacy of bone grafts in jaw cystic lesions:A systematic review

BACKGROUND Bone grafts have been applied for many years in orthopedic surgery to assist with bone repair for defects or bone discontinuity caused by trauma and tumors as well as periodontal defects.Jaw cysts are another common benign disease of the maxillofacial region which may lead to pathological bone fracture,loss of teeth,and infection.However,whether bone grafts are beneficial for bone regeneration in jaw cystic lesions and when bone grafts should be used remains unclear.AIM To study the efficacy of bone grafts compared to spontaneous healing in the treatment of jaw cystic lesions.METHODS A literature search was performed in Medline,Cochrane Library and Embase to identify related articles published in English in the last ten years.The following key words and Me SH terms were used:“jaw cyst”,“cystic lesion”,“odontogenic cyst”,“periapical cyst”,“dentigerous cyst”,“follicular cyst”,“keratocyst”,“treatment”,“surgery”,“bone graft”,“enucleation”,“cystectomy”,and“bone regeneration”.Case reports,clinical trials,clinical studies,observational studies and randomized controlled trials were included.Study quality was evaluated.RESULTS Ten studies(n=10)met the inclusion criteria.Five studies reported spontaneous bone healing after enucleation,three studies investigated the efficacy of various bone grafts,and two randomized comparative studies focused on the comparison between spontaneous healing and bone grafting.Over 90%of bone regeneration occurred within 6 mo after bone grafting.The bone regeneration rate after cystectomy showed great variation,ranging from 50%to 100%after 6 mo,but reaching over 90%after 12 mo.CONCLUSION While the long-term superiority of bone grafting compared with spontaneous healing after cystectomy is unclear,bone grafts accelerate the process of healing and significantly increase bone quality.

Mandibular Buccal Bifurcation Cyst:Report of Two Cases

Mandibular buccal bifurcation cyst is a rare inflammatory odontogenic cyst.We reported two cases who complained of painful swelling of extraoral soft tissue.Intraoral examination revealed the partially erupted mandibular first molar.Cone beam computed tomography showed a well-defined cystic lesion surrounding the first molar.Histopathologic images showed the cyst wall was infiltrated by a large number of plasma cells,neutrophils and eosinophils,and lined with a thin layer of non-keratinized stratified squamous epithelium.Finally,the two patients were diagnosed as mandibular buccal bifurcation cyst and treated with cyst enucleation and curettage.

Solitary intraosseous neurofibroma in the mandible mimicking a cystic lesion:A case report and review of literature

BACKGROUND Neurofibromas are benign tumors of a neurogenic origin.If these tumors occur without any other signs of neurofibromatosis,they are classified as isolated neurofibromas.Neurofibromas in the oral cavity mostly occur within soft tissues,indicating that solitary intraosseous neurofibromas in the mandible are rare.Due to the absence of specific clinical manifestations,early diagnosis and treatment of these tumors are difficult to achieve.CASE SUMMARY A 37-year-old female patient visited our hospital due to numbness and swelling of the gums in the right lower molar area that had persisted for half a month.The patient’s overall condition and intraoral examination revealed no significant abnormalities.She was initially diagnosed with a cystic lesion in the right mandible.However,after a more thorough examination,the final pathological diagnosis was confirmed to be neurofibroma.Complete tumor resection and partial removal of the right inferior alveolar nerve were performed.As of writing this report,there have been no signs of tumor recurrence for nine months following the surgery.CONCLUSION This case report discusses the key features that are useful for differentiating solitary intraosseous neurofibromas from other cystic lesions.

Pattern of occurrence of jaw cysts and cyst-like lesions at the University of Nairobi Dental Hospital: A 10-year histopathologic audit

Background: Jaw cysts and cyst-like lesions cause facial deformity, destruction of dental tissues and affect masticatory and phonation functions. These ad-versely erode patients’ psycho-social status;create low self-esteem and may change one’s facial identity and appearance. Objective: To determine the histo-pathologic characteristics, variants and demographic pattern of jaw cysts and cyst-like lesions at the University of Nairobi Dental Hospital. Material and Me-thod: This was an analytical and verification study that involved microscopic re-examination of all available incisional/excisional biopsy samples from January 2000 to December 2009 for histo-pathological diagnosis at the University of Nairobi Dental Hospital. Results: 187 jaw cysts and cyst-like lesions were diagnosed at the University of Nairobi Dental Hospital over the ten-year period. Keratocystic odontogenic tumours constituted 28%, dentigerous cysts 25%, nasopalatine duct cysts 19%, radicular cysts 15%, while calcifying odontogenic cysts comprised 4% of all the lesions. The rest of the lesions were between 1% and 3% of all the lesion entities. Conclusion: Keratocystic odontogenic tumours and dentigerous cysts were the most common developmental odontogenic cysts diagnosed in the ten-year period.

Primitive Peritoneal Hydatic Calcified Cyst —A Case Report

It is a cosmopolitan disease, due to the embryonic shape of taenia of the dog Ecchinococcosis granulosis. The peritoneal hydatidosis is the sowing of this serous in a primitive or secondary way. It can be caused by the massive break of a visceral hydatid cyst realizing the anaphylactic shock. Somewhere else, the discreet fissuring is the most usual realizing peritoneum cysts. So the peritoneal hydatidosis appears under polymorphic clinical painting according to the anatomical location of cysts. The disease puts a real problem of public health in our country. The primitive peritoneal localization is rare. We report a case of a primitive intra-peritoneal hydatid cyst.

Orofacial Cysts at Komfo Anokye Teaching Hospital, Ghana

Background: Information about orofacial cysts from African populations is scarce and there are only a few studies available regarding the prevalence of these lesions in the West African sub-region. The purpose of the present study is to determine the distribution and prevalence of all histologically diagnosed orofacial cysts in Kumasi, Ghana. Aim: To determine prevalence, sex, age and anatomic distribution of orofacial cyst seen at the oral and maxillofacial unit in Komfo Anokye Teaching hospital (KATH). Method: This is a retrospective study, which examined histologically diagnosed lesions including orofacial cysts. The study duration was from 1999 to 2010 September inclusive. Results: There were 37 odontogenic cysts constuting 6.5%, of all orofacial lesions. There were 18 non-odontogenic cysts i.e. 3.1% of all lesions diagnosed during the study period. The odontogenic cysts comprised 19 (51.4%) developmental cysts and 18 (48.6%) inflammatory cysts. Male-to-female ratio for the orofacial cysts was 1:1 and the mean age was 36.7 years. Conclusion: There is low prevalence of the odontogenic cysts, which is consistent with findings from other African studies. Although radicular cysts accounted for the majority of orofacial cysts in this study, the prevalence of radicular cysts is low compared to reports from developed countries.

Ankle and toe weakness caused by calcified ligamentum flavum cyst: A case report

BACKGROUND Ligamentum flavum cysts,which are most common in mobile junctional levels of the spine,can be a rare cause of spinal stenosis.There have been several case reports of ligamentum flavum cysts.However,there is yet to be a documented case report of a calcified ligamentum flavum cyst.Herein,we report the first case of a calcified ligamentum flavum cyst causing ankle and toe weakness.CASE SUMMARY A 66-year-old male visited our hospital complaining of claudication as well as thigh and calf pain in his left leg,all beginning two weeks prior.Physical examination revealed motor weakness of the left ankle dorsiflexion and great toe dorsiflexion.Lumbar spinal computed tomography scans showed spinal stenosis combined with a calcified mass at the left side of the L4-5 level.Magnetic reso-nance imaging showed dural sac compression caused by the calcified mass at the left ligamentum flavum of the L4-5 level.We performed decompressive laminectomy and excision of the calcified mass combined with posterior lumbar interbody fusion at the L4-5 level.Intra-operatively,we found a firm and nodule like mass originating from the ventral surface of ligamentum flavum.Pathological examination suggested a calcified pseudocyst without a capsular lining.After the operation,the patient’s motor weakness in the ankle and great toe improved gradually.CONCLUSION The patient’s ankle and great toe weakness were improved successfully after surgical removal of the calcified cyst.

Klestadt’s Cyst: Case Report

Klestadt’s cyst, more commonly known as the nasolabial cyst, is an uncommon, non-odontogenic, and soft tissue cyst. It is classified as a fissural cyst, found outside the bone, and on the region corresponding to the nasolabial furrow and alar nose. Following its description first by Zukuerkandl in 1882, only 267 cases have been found in English literature. In spite of the low occurrence of nasolabial cysts, it is important to recognize the clinical characteristics of this lesion. The purpose of this report is to review the literature and discuss the histomorphology and etiology of this condition, and also its management by surgical excision. As per our experience, sublabial approach is the best for complete and scarless excision of this cyst.