Reconstruction of Mandibular Defects With Bone Marrow-Derived Stem Cells in Odontogenic Myxoma.

Odontogenic myxoma is a benign tumor, mostly located in the mandible. It shows locally aggressive behavior and requires surgical removal. Common treatment options for reconstructing the bone defects are immediate or delayed autologous bone graft or free flap. In this article, the authors present the successful reconstruction with autogenous bone graft and autologous human bone marrow mesenchymal stem, followed by distraction osteogenesis, dental implant placement and prosthodontic restoration in the mandibular defect.

Interventions for the treatment of keratocystic odontogenic tumours.

BACKGROUND: The keratocystic odontogenic tumours (KCOTs) account for between about 2% and 11% of all jaw cysts and can occur at any age. They are more common in males than females with a male:female ratio of approximately 2:1. Although they are benign, KCOTs are locally very aggressive and have a tendency to recur after treatment. Reported recurrence rates range from 3% to 60%. The traditional method for the treatment of most KCOTs is surgical enucleation. However, due to the lining of the cyst being delicate and the fact that they frequently recur, this method alone is not sufficient. Adjunctive surgical treatment has been proposed in addition to the surgical enucleation, such as removal of the peripheral bone (ostectomy) or resection of the cyst with surrounding bone (en-bloc) resection. Other adjunctive treatments proposed are: cryotherapy (freezing) with liquid nitrogen and the use of the fixative Carnoy's solution placed in the cyst cavity after enucleation; both of which attempt to address residual tissue to prevent recurrence. OBJECTIVES: To assess the available evidence comparing the effectiveness of interventions for the treatment of KCOTs. SEARCH METHODS: We searched the following electronic databases: the Cochrane Oral Health Group Trials Register (to 17 March 2015), the Cochrane Central Register of Controlled Trials (CENTRAL) (The Cochrane Library, 2015, Issue 2), MEDLINE via Ovid (1946 to 17 March 2015) and EMBASE via Ovid (1980 to 17 March 2015). We searched the US National Institutes of Health Trials Register (http://clinicaltrials.gov) and the WHO Clinical Trials Registry Platform for ongoing trials. No restrictions were placed on the language or date of publication when searching the electronic databases. SELECTION CRITERIA: Randomised controlled trials comparing one modality of intervention with another with or without adjunctive treatment for the treatment of KCOTs. Adults, over the age of 18 with a validated diagnosis of solitary KCOTs arising in the jaw bones of the maxilla or mandible. Patients with known Gorlin syndrome were to be excluded. DATA COLLECTION AND ANALYSIS: Review authors screened trials for inclusion. Full papers were obtained for relevant and potentially relevant trials. If data had been extracted, it would have been synthesised using the fixed-effect model, if substantial clinical diversity were identified between studies we planned to use the random-effects model with studies grouped by action provided there were four or more studies included in the meta-analysis, and we would have explored the heterogeneity between the included studies. MAIN RESULTS: No randomised controlled trials that met the inclusion criteria were identified. AUTHORS' CONCLUSIONS: There are no published randomised controlled trials relevant to this review question, therefore no conclusions could be reached about the effectiveness or otherwise of the interventions considered in this review. There is a need for well designed and conducted randomised controlled trials to evaluate treatments for KCOTs.

Keratocystic Odontogenic Tumour with Extraosseal Spread: Evaluation of the Effect Carnoy's Solution.

Keratocystic odontogenic tumour is relatively rare benign tumour. It is characterized by its fast aggressive growth and high risk of recurrence. Treatment is always surgical: conservative (enucleation, marsupialization) or aggressive (enucleation followed by application of Carnoy's solution, cryotherapy; peripheral ostectomy or en block resection of the jaw). Authors analysed retrospectively 22 patients who fulfilled inclusion criteria, i.e. had odontogenic keratocystic tumour of mandible, wherein antero-posterior dimension was at least 30 mm, and the tumour penetrated into the surrounding soft tissues. All patients underwent tumour enucleation, in 11 patients Carnoy's solution was given into the bone cavity after enucleation. The recurrence rate in the evaluation at least 36 months after surgery was both patient groups the same: 45.4%.

Primordial odontogenic tumour: clinicopathological analysis of six cases of a previously undescribed entity.

AIM: To describe the clinicopathological and immuno-histochemical features of six tumours that do not fulfil the criteria of any of the currently classified odontogenic tumours. METHODS AND RESULTS: The patients were three males and three females, whose ages ranged from 3 years to 18 years (mean, 11.05 years). In all cases there were well-defined radiolucencies associated with unerupted teeth apparently showing a pericoronal relationship. Microscopically, all tumours were composed of variably cellular loose fibrous tissue with areas similar to dental papilla, entirely surrounded by cuboidal to columnar epithelium resembling the internal epithelium of the enamel organ. Mesenchymal tissue was positive only for vimentin, and Ki67 expression was very low (<2%). The epithelium was positive for CK AE1/AE3, CK5, CK14, and CK19, but negative for CK18 and CK20. All cases showed clear demarcation from the surrounding bone, and were surgically removed, with no recurrences after follow-up ranging from 6 months to 20 years. CONCLUSIONS: These findings differ from those observed in other odontogenic lesions, such as ameloblastic fibroma, odontogenic myxoma, odontogenic fibroma, and hyperplastic dental follicles. The term primordial odontogenic tumour is proposed to describe this novel lesion.

Malignant transformation of keratocystic odontogenic tumor: two case reports.

INTRODUCTION: Keratocystic odontogenic tumors (KCOTs) are cystic tumours originating from the dental lamina of the maxilla and mandible that are lined with keratinized epithelium. While benign, they can be locally destructive and have a high recurrence rate despite treatment. Rarely, KCOTs may undergo malignant transformation into Primary Intraosseous Squamous Cell Carcinoma (PIOSCC). CASE REPORT: This study reports the clinical findings, radiological scans and histopathology of 2 patients with KCOTs that underwent malignant transformation into PIOSCC. DISCUSSION: A comprehensive literature review was performed to similar reports documenting the malignant transformation of KCOTs. The potential for KCOTs to undergo malignant change should prompt oral maxillofacial surgeons and otolaryngologists to exercise a high index of suspicion when treating these lesions. Patients persisting with unresolved disease after treatment should be investigated for malignant transformation. Detailed histopathological examination of KCOT specimens is recommended to detect small foci of SCC which may be present in the epithelium.

Ghost cell odontogenic carcinoma: A rare case report and review of literature.

RATIONALE: Ghost cell odontogenic carcinoma is a rare malignant odontogenic carcinoma characterized by the presence of ghost cells. It has a nonspecific clinical and radiographic presentation and can be locally destructive and invasive, sometimes with distant metastases. However, no effective systemic therapy is currently recommended for such patients. PATIENT CONCERNS: The patient has been unable to undergo surgery or radiotherapy again. Therefore, he was referred to our department for a more aggressive, multimodal systematic treatment program. DIAGNOSES: The histopathological examination was morphologically suggestive of ghost cell odontogenic carcinomas. INTERVENTIONS: We report a case of locally invasive primary inoperable odontogenic shadow cell carcinoma in a 31-year-old Chinese man who achieved treatment with Toripalimab and chemotherapy, followed by Toripalimab maintenance therapy after 6 cycles. OUTCOMES: He achieved partial remission after treatment. The quality of life significantly improved after treatment. There were no grade 3/4 treatment-related adverse events during treatment. LESSONS: This case presented that Toripalimab and chemotherapy may be a safe and effective systemic therapy for ghost cell odontogenic carcinoma.

Clinical, diagnostic and therapeutic features of keratocystic odontogenic tumors: a review.

Keratocystic odontogenic tumors (KCOTs) are benign but locally aggressive lesions of the gnathic skeleton with high propensity to recur following surgical treatment. High proliferative activity of KCOTs epithelial cells is considered as one of the factors contributing to their aggressive clinical behavior. Aggressive growth within the jaws, tendency to invade surrounding anatomical structures and occasional malignant alteration are the features that distinguish KCOTs from other types of odontogenic tumors. Due to their unique clinical and biological features, KCOTs still present an important problem in oral and maxillofacial surgery. This is especially true when a choice of the most appropriate treatment modality should be made. Establishing balance between effective reduction of recurrence risk and selection of a less aggressive surgical procedure is an issue that should be carefully considered for each individual patient.

Enucleation and liquid nitrogen cryotherapy in the treatment of keratocystic odontogenic tumors: a case series.

PURPOSE: This study describes the technique of lesion enucleation without capsule disruption combined with liquid nitrogen cryotherapy in the surgical treatment of keratocystic odontogenic tumors (KOTs). PATIENTS AND METHODS: Eight patients (9 KOTs) were included in the study. After enucleation, liquid nitrogen was applied twice for 1 minute, with 5-minute intervals between applications. The patients were followed up for 3 to 9 years. RESULTS: There were no recurrences during the follow-up of 9 KOTs for up to 9 years. Only 1 patient had temporary reversible loss of lip sensation after treatment. There were no pathologic fractures. In all cases bone height at the surgical site was restored, and no patients needed bone reconstruction for post-treatment rehabilitation. CONCLUSIONS: This study confirmed the efficiency of KOT treatment enucleation without fragmentation combined with liquid nitrogen cryotherapy at the surgical site.

Retrospective study of 25 cases of keratocystic odontogenic tumor: epidemiology and treatment.

AIM: Keratocystic odontogenic tumor (KOT) is a benign odontogenic neoplasm with locally aggressive behavior and high recurrence rates. It is associated with nevoid basal cell carcinoma syndrome which usually has a more rapid growth. The aim of the study is to report the experience of our service on diagnosis and treatment of KOT. MATERIALS AND METHODS: Twenty-five cases of KOT were diagnosed between the years of 1989 and 2006. Demographic data was collected as well as diagnose and treatment. RESULTS: Fifty-six percent were female with a mean age of 33 years old. Seventy percent occurred in mandibula and all received surgical treatment, associate or not with adjuvant therapy, such as cryotherapy and Carnoy's solution. Recidive was observed in 48% of cases with a mean period of time of 18 months. CONCLUSION: Our data analysis showed the importance of previous diagnosis before enucleation procedure and long-term follow-up for recurrence early detection. Recurrence incidence is more frequent on first year after diagnosis. CLINICAL SIGNIFICANCE: KOT is a benign tumor with local aggressive behavior and therefore its treatment must consider the high index of recidive. Reports of protocol treatment should raise new discussion to decrease recurrence rates.

Patterns of Care and Survival Outcomes for Odontogenic Cancers.

OBJECTIVES: Our understanding of odontogenic cancers is limited primarily to case studies given the rarity of these head and neck neoplasms. Using the National Cancer Database, we report the treatment patterns and survival outcomes for one of the largest cohorts of patients with odontogenic cancers. METHODS: Patients with odontogenic tumors who did not have metastatic disease and received at least part of their care at the reporting facility were included. Patient and treatment variables were assessed using logistic regression. Survival was assessed using Cox proportional hazard models. RESULTS: We identified 437 patients with odontogenic cancers, the majority of which had malignant ameloblastoma (n = 203) or odontogenic carcinoma (n = 217). Median follow-up was 44.8 months. On multivariate analysis, improved survival was associated with age <57 years (Hazard ratios [HR] 0.44, P = .012), lower comorbidity scores (HR 0.40, P = .008), surgical resection (HR 0.08, P < .001) and absence of lymph node metastasis (HR 0.23, P < .001). The 5-year overall survival was 87.1% for debulking surgery, 88.6% for radical resection and 26.6% for no surgical resection (P < .001). Lymph node metastases were associated with tumor size ≥5 cm (P = .006), malignant odontogenic histology (P = .025), and moderate/poor differentiation (P < .001). CONCLUSION: In this large series of odontogenic cancers, any type of surgical resection was associated with improved survival. Lymph node metastases, although infrequent, were associated with significantly worse survival. LEVEL OF EVIDENCE: Level 3 Laryngoscope, 131:E1496-E1502, 2021.

Interventions for the treatment of keratocystic odontogenic tumours (KCOT, odontogenic keratocysts (OKC)).

BACKGROUND: The keratocystic odontogenic tumours (KCOTs) account for between about 2% and 11% of all jaw cysts and can occur at any age. They are more common in males than females with a male:female ratio of approximately 2:1. Although they are benign, KCOTs are locally very aggressive and have a tendency to recur after treatment, reported recurrence rates range from 3% to 60%. The traditional method for the treatment of most KCOTs is surgical enucleation. However, due to the lining of the cyst being delicate and the fact that they frequently recur, this method alone is not sufficient. Adjunctive surgical treatment has been proposed in addition to the surgical enucleation, such as removal of the peripheral bone (ostectomy) or resection of the cyst with surrounding bone (en-bloc) resection. Other adjunctive treatments proposed are: cryotherapy (freezing) with liquid nitrogen and the use of the fixative Carnoy's solution placed in the cyst cavity after enucleation; both of which attempt to address residual tissue to prevent recurrence. OBJECTIVES: To assess the available evidence comparing the effectiveness of surgical interventions and adjuncts for the treatment of KCOTs. SEARCH STRATEGY: Databases searched were: the Cochrane Oral Health Group's Trials Register (to 28th July 2010), CENTRAL (The Cochrane Library 2010, Issue 3), MEDLINE (from 1950 to 28th July 2010), and EMBASE (from 1980 to 28th July 2010). The reference lists of all trials identified were cross checked for additional trials. There were no language restrictions and several articles were translated. SELECTION CRITERIA: Randomised controlled trials comparing one modality of surgical intervention with another with or without adjunctive treatment for the treatment of KCOTs. Adults, over the age of 18 with a validated diagnosis of solitary KCOTs arising in the jaw bones of the maxilla or mandible. Patients with known Gorlin syndrome were to be excluded. DATA COLLECTION AND ANALYSIS: Review authors screened trials for inclusion. Full papers were obtained for relevant and potentially relevant trials. If data had been extracted, it would have been synthesised using the fixed-effect model, if substantial clinical diversity were identified between studies we planned to use the random-effects model with studies grouped by action provided there were four or more studies included in the meta-analysis, and we would have explored the heterogeneity between the included studies. MAIN RESULTS: No randomised controlled trials that met the inclusion criteria were identified. AUTHORS' CONCLUSIONS: There are no published randomised controlled trials relevant to this review question, therefore no conclusions could be reached about the effectiveness or otherwise of the interventions considered in this review. There is a need for well designed and conducted randomised controlled trials to evaluate treatments for KCOTs.

Keratocystic odontogenic tumor (odontogenic keratocyst): preliminary retrospective review of epidemiologic, clinical, and radiologic features of 261 lesions from University of Turin.

PURPOSE: To analyze and discuss the demographic, clinical, and surgical aspects of 261 surgically treated keratocystic odontogenic tumors. PATIENTS AND METHODS: A retrospective review was performed of all cases of treated keratocystic odontogenic tumors. Statistical analysis was used to search for associations among age, presenting symptoms, location, dimension, and locularity. RESULTS: Keratocystic odontogenic tumors most commonly occurred in patients in the third and fourth decades of life. The ratio of males to females was 2:1. The mandibular angle region was the most frequently involved site. Significant associations were found between multilocular lesions and lesions larger than 31 mm (P < .00000005), a mandibular site and larger lesions (P < .05), patients younger than 41 years old and multilocular lesions (P < .05), and younger patients and larger lesions (P < .00005). CONCLUSION: It is likely that most multilocular, larger (and probably aggressive) lesions are found in patients younger than 41 years of age.

Immunoexpression of Ki67, proliferative cell nuclear antigen, and Bcl-2 proteins in a case of ameloblastic fibrosarcoma.

Ameloblastic fibrosarcoma (AFS), regarded as the malignant counterpart of the benign ameloblastic fibroma, is an extremely rare odontogenic neoplasm with only 68 cases reported in the English literature up to 2009. It is composed of a benign odontogenic epithelium, resembling that of ameloblastoma, and a malignant mesenchymal part exhibiting features of fibrosarcoma. Due to the rarity of the lesion, little is known about its molecular pathogenesis; therefore, in the current study, we sought to evaluate the immunoexpression of Ki67, proliferative cell nuclear antigen, and Bcl-2 proteins in AFS, comparing the results obtained with its benign counterpart, as well as to report a new case of this rare entity affecting a 19-year-old female patient. The results obtained revealed that all the proteins evaluated were overexpressed in the malignant mesenchymal portion of AFS if compared with ameloblastic fibroma, suggesting that nuclear proliferative factors such as Ki67 and proliferative cell nuclear antigen, in association to histopathologic features, may be useful markers for identifying the malignancy and that, despite the lack of molecular analysis in the case reported, Bcl-2 alteration may play a role in AFS pathogenesis.

[Odontogenic myxoma: About four cases and review of the literature]. / Le myxome odontogénique : étude de quatre cas et revue de la littérature.

OBJECTIVE: Odontogenic myxoma is an uncommon tumor that represent less than 0,5% of all bone tumors and only 3 to 6% of odontogenic tumors. The aim of this article was to catalogue the clinical cases diagnosed microscopically as odontogenic myxoma and to describe their clinical and radiographic characteristics, comparing these to the data found in the current literature. DESIGN: Histological and immunocytochemical examinations were performed on odontogenic myxomas from four Tunisian patients in a period of 23 years. RESULTS: In the present series, two were male and two female. The age at diagnosis ranged from 19 to 38 years. Three tumors involved the mandible and one occurred in the maxilla. In all cases with radiographic records, lesions presented with a multilocular and osteolytic appearance. Histologically, odontogenic myxomas were mainly composed of spindled or stellate-shaped cells in a mucoid-rich intercellular and alcian blue positive matrix. All cases were treated by tumor-enucleation. There was no evidence of recurrence after 2 to 8 years. CONCLUSION: Clinical and radiological aspects of odontogenic myxomas are not conclusive; a histopathological examination of the lesion is mandatory in order to make the right diagnosis. Because of its high rate of recurrence, surgical treatment through bone resection is the most indicated treatment modality, and the patient must be followed-up closely for years.

Malignant fibrous histiocytoma - a case report.

Fibrous histiocytoma is a mesenchymal neoplasm with benign and malignant varieties. This tumor mainly affects the skin of extremities in adults and may on rare occasions affect the oral cavity. The tumor has radiographic features in very rare cases. The present case report aims to conduct a clinicopathological-radiographic and immunohistochemical assessment and treatment of a patient with this lesion.

The dentigerous cyst: two different treatment options illustrated by two cases / Die follikuläre Zyste: zwei unterschiedliche Behandlungsmöglichkeiten, präsentiert anhand zweier Fallbeispiele

The dentigerous cyst is the second most frequent odontogenic cyst after the radicular one. Typically, dentigerous cysts are asymptomatic and are commonly diagnosed incidentally. Due to the slow, expansive growth dentigerous cysts have the potential for dislocation of adjacent structures (neighbouring teeth, canalis retromolaris), root resorptions and in an extreme case could cause jaw fractures. A histological examination represents a sine qua non, because other more alarming pathologies (odontogenic keratocyst, unicystic ameloblastoma, myxoma, primordial odontogenic tumour etc.) can exhibit clinically and radiologically a similar appearance. This brief overview aims to illustrate, by two clinical cases, the examination, the diagnosis and decision-making for either a cystostomy or a cystectomy. The surgical procedure of both techniques is presented in a step-by-step manner.

[Clinical and imaging features of 36 odontogenic keratocysts associated with an impacted tooth].

PURPOSE: To analyse the imaging features of odontogenic keratocysts (OKCs) associated with an impacted tooth. METHODS: Clinical and radiological data of 235 cases with OKCs were respectively investigated, with emphasis on imaging features of 36 OKCs, which were associated with an unerupted tooth. RESULTS: In 36 cases of OKCs associated with an impacted tooth, the ratio of male to female was 1.77:1, and molar-ramus was involved in 26 cases (72.22％). OKCs in association with an unerupted tooth occurred mostly in patients ranging from 20 to 30 years (19 cases, 52.8％). There were 27 cases (75％) of unilocular and 9 cases (25％) multilocualr radiolucency. Thirteen cases (36.11%) were related to the crown of the impacted teeth, and the unerupted teeth also were impacted as a result of malposition in which the entire teeth appeared to be enveloped by cysts (15 cases, 41.67%), or adjacent to cyst wall (8 cases, 22.22%). CONCLUSIONS: Radiographically, one of the most imaging features of OKCs in association with an unerupted tooth is that its entire tooth appears to be enveloped by cyst or adjacent to cyst, while pericoronal radiolucencies surrounding an impacted tooth are rarely seen.