Novel recurrence risk stratification of odontogenic keratocysts: A systematic review.

The aim of this study was to identify all clinical, radiological, histopathological, and immunohistochemical features associated with recurrence of odontogenic keratocysts (OKCs) in the literature and formulate a recurrence risk stratification based on these findings. A search was performed in PubMed/Medline, Scopus, Web of Science, Google Scholar and Cochrane databases for clinical and laboratory studies reporting on clinico-pathological features that led to OKC recurrences for the period 2000 to 2020. Twenty-three studies were identified and analyzed qualitatively. A total of 2064 OKCs were included of which 439 OKCs were recurrent with a mean follow-up period of 46.7 months. Significantly associated parameters with OKC recurrence included age (variable age categories), large (>4 cm), multilocular lesions with cortical perforation, association with dentition, presence of daughter cysts, and epithelial budding. Immunohistochemical markers including high Ki67 index and AgNOR count were also implicated. A recurrence risk stratification was formulated based on these findings. Although the level of evidence from the included studies was low, there was considerable evidence that the clinico-pathological parameters identified were linked with higher OKC recurrence. The surgeon, radiologist, and pathologist should aim to identify these features when making a diagnosis so as to determine the appropriate management regime and prevent recurrences.

Odontogenic myxoma: a clinicopathological study in a South African population.

BACKGROUND: Odontogenic myxoma is a benign, locally aggressive neoplasm of the jaws. Prevalence rates range between 0.5% and 17.7% of odontogenic tumours. There are few reports in the literature on this lesion in African populations, and therefore, this study aimed to report on odontogenic myxoma in a South African population over a 40-year period. METHODS: The clinical records and orthopantomograms of 29 histopathologically diagnosed odontogenic myxoma were retrospectively analysed. Details of age, gender, ethnic origin and clinical, histological as well as radiological features were recorded. RESULTS: The ages of patients ranged from 7 to 44 years with a mean of 21.3 years. The male-to-female ratio was 1:2.6 with the majority of patients being of mixed race and Africans. Clinically, 31% complained of pain while 58.6% had a history of swelling. The majority of odongenic myxomas (62.1%) were located in the mandible with the posterior region being most commonly affected. Multilocular lesions (69.2%) were more common and were significantly larger than unilocular lesions (P < 0.05). The outline of these tumours was mostly well-defined (84.6%) with different degrees of cortication. Only one tumour caused tooth resorption, while 20 cases (76.9%) caused tooth displacement. Six tumours expanded into the maxillary sinus, and 14 tumours caused expansion of the mandible. CONCLUSIONS: Odontogenic myxomas have variable clinical, radiological and histological features. Most of these features in this population were similar to other populations. It is mandatory to use conventional radiographs along with histopathological examination to aid in arriving at an accurate diagnosis.

Ossifying Fibroma: Analysis of Treatment Methods and Recurrence Patterns.

PURPOSE: Ossifying fibroma (OF) is one of the most frequent of the 3 fibro-osseous lesions of the jaws and has had an inconstant recurrence rate. A definitive surgical protocol has not yet been published. The aim of the present study was to determine the clinical and radiologic features of OF at a tertiary hospital in South Africa, assess its management and recurrence patterns, and develop a surgical protocol. MATERIALS AND METHODS: A retrospective case-series analysis was performed of all histopathologically diagnosed OF cases from 1976 to 2014. The demographic data, clinical presentation, and radiographic features were analyzed. The management of each case and follow-up data were also documented. A surgical protocol was developed using these findings. RESULTS: A total of 61 cases were included in the present study. Most of the patients were female (63.9%) and younger than 40 years old (73.9%), and only few cases were symptomatic (29.5%). The mandibular posterior region was affected most often (55.5%), and most lesions were radiopaque (49.2%) and had well-defined margins (93.6%). Most cases were managed by surgical curettage (68.2%). After an average follow-up period of 20 months, only 1 case had recurred for a recurrence rate of 6.7%. CONCLUSIONS: The lesions in our population were more radiopaque and larger than those in the published data. Surgical curettage is an acceptable management protocol with a low rate of recurrence, and resection should be reserved for aggressive and recurrent lesions.

Osteosarcoma associated with cemento-osseous dysplasia: co-incidence or two related entities?

BACKGROUND: Osteosarcoma of the jaws is a rare primary malignant tumor of bone. The clinical, radiological and histopathological features of a case associated with cemento-osseous dysplasia is presented. CASE REPORT: A 57-year-old mixed-race female presented with a large, progressive, swelling of the right mandible. Radiographic examination revealed two associated lesions. Partially defined irregular radiopacities were noted in the left mandible, extending from the premolar to the molar region. The lesion had a cotton-wool appearance and resembled a fibro-osseous lesion; i.e. cemento-osseous dysplasia. A second large, expansive and irregular, radiopaque lesion was noted on the right angle of the mandible, extending beyond the inferior cortex of the mandible. The internal structure was heterogeneous and resembled irregular bone formation. The classic "sunburst" appearance of radiating bony spicules can be seen in the posterior-anterior view and the CBCT 3D reconstruction, indicating the outgrowth of the tumor matrix. Histopathological exam confirmed a final diagnosis of osteosarcoma closely associated with cemento-osseous dysplasia. The patient underwent a fludeoxyglucose-18 (FDG) positron emission tomography (PET) scan which indicated metastasis in the left lung and increased uptake in the right mandible. Chemotherapy was initially administered with a plan to resect the tumor, however, the patient demised as a result of medical complications. CONCLUSION: The question in the literature remains whether these two entities are coincidentally found or arise from each other. Nevertheless, it is important for clinicians to closely monitor patients with cemento-osseous dysplasia and biopsy any suspicious lesions that may develop into osteosarcoma.

Nevoid basal cell carcinoma syndrome: a 40-year study in the South African population.

BACKGROUND: Nevoid basal cell carcinoma syndrome (NBCCS) is a hereditary autosomal dominant syndrome presenting with a number of signs and symptoms in different population groups. METHODS: The investigators implemented a 40-year retrospective analysis of the clinical and radiological features of South Africans affected by NBCCS presenting at the Departments of Oral Surgery, Pathology and Radiology of two major referral hospitals. Details of age, gender, ethnic origin, clinical, and radiological findings were recorded and compared to previous reports. A list of diagnostic criteria for diagnosis of NBCCS in this population was complied. Descriptive statistics were computed, and the P value was set at 0.05 or less. RESULTS: The sample was composed of 15 patients. The mean age at the time of diagnosis was 22.7years (SD 20.9) with eight (53.3%) patients diagnosed before 20years of age (P=0.0001). The male: female ratio was 2:1. The most frequent major criteria were keratocystic odontogenic tumors (KCOTs) (100%), calcification of falx cerebri (40%), palmo-plantar pits (26.7%), and basal cell carcinomas (BCCs) (20%). The most frequent minor criteria were bifid ribs (20%), skull anomalies (20%), and hypertelorism (20%). CONCLUSIONS: The results of this study indicate that there was a low frequency of falx cerebri calcifications, BCCs, skull, and rib anomalies in this sample compared to other population groups. These differences could be attributed to genetic, racial, and environmental factors. Future studies are needed to compile diagnostic criteria specific to different population groups.

Application of 5-Fluorouracil in management of glandular odontogenic cyst.

Glandular odontogenic cyst (GOC) is a rare, aggressive odontogenic lesion that presents in the jaws. It is a diagnostically challenging entity due to its ability to mimic intraosseous mucoepidermoid carcinoma, botryoid cyst, surgical ciliated cyst, and radicular cyst. Treatment ranges from conservative to aggressive surgical interventions due to its varied clinical and radiological appearance and also its potential for recurrence. Aggressive surgical interventions result in the need for surgical site reconstruction, thus increasing patient morbidity. We report a case of GOC in the anterior mandible that was conservatively treated by the application of 5-Fluorouracil (5-FU). Topical application of 5-FU was selected in the management of this lesion as it has shown to be effective in reducing recurrence rates of other aggressive odontogenic lesions such as odontogenic keratocysts. To our knowledge, this is the first case reported in the literature that was successfully treated by the combination of cyst enucleation, curettage, peripheral ostectomy and application of 5-FU. No recurrence was detected after 14-month follow-up. Key words:Odontogenic cysts, Fluorouracil, Recurrence.

Clinical indications for radical resection of odontogenic keratocyst: A systematic review.

The aim of this study was to identify clinico pathological indications for radical resection of odontogenic keratocysts (OKCs) in the literature and formulate clinical guidelines for the management of OKCs based on these findings. A systematic review of the literature was undertaken in September 2021 in PubMed/Medline, Scopus, Web of Science, Google Scholar, and Cochrane databases. The following MeSH Keywords terms were used in the search strategies: (odontogenic keratocyst) OR (keratocystic odontogenic tumor) OR (primordial cyst) AND (treatment) OR (Radical resection) OR (Resection of OKC) OR (Treatment methods). Eligibility criteria included publications of clinical studies on histologically confirmed OKCs which underwent radical resection. Studies with less than 5 OKCs, experimental studies, epidemiological studies, studies that included orthokeratinized odontogenic cyst, and review papers were excluded. Ten studies on OKCs reporting on segmental or marginal resections were identified and analyzed qualitatively. Of the total of 221 OKCs that underwent radical resection, 67 OKCs were primary, 30 were recurrent, and the remaining were unclear whether they were primary or recurrent. Segmental mandibulectomy was performed in 131 OKCs, marginal mandibulectomy in 87 OKCs, and 3 OKCs were treated by partial maxillectomy. The main indications for radical resection were multilocular appearance, large OKCs (> 5 cm), multiple recurrent OKCs with or without cortical perforation, and malignant transformation. In conclusion, radical resection has its place in the management of OKC. It is indicated when there is an aggressive lesion with bony perforation, involvement of the pterygoid musculature or skull base, and malignant transformation. The surgeon should aim to identify these features to manage OKC appropriately and to prevent multiple recurrences. Clinical guidelines for the management of OKCs are proposed.

Unicystic ameloblastoma: analysis of surgical management and recurrence risk factors.

Unicystic ameloblastoma is a distinct pathological variant with varying evidence published about its behaviour and surgical management. Due to a paucity of large studies in the literature with long-term follow up, the aim of this study was to analyse its surgical management and identify clinicopathological features associated with recurrences. All histopathologically confirmed lesions diagnosed at two referral centres between 1995 and 2020 were retrospectively analysed. Demographic, clinical, radiological, and histopathological features were analysed along with surgical methods and follow-up data. Univariate regression analyses were performed to identify risk factors for recurrence. Sixty-three patients were included in the study with mean age of 26.3 years and a male to female ratio of 1:0.75. The majority of lesions occurred in the posterior mandible (57.1%) and were unilocular (88.9%). Most lesions were managed with enucleation followed by application of Carnoy's solution (ferric chloride: 1g; chloroform: 3 mL; glacial acetic acid: 1 mL; ethyl alcohol 96%: 6 mL) and burring of the peripheral bone margin which resulted in the lowest recurrences (9.1%) besides resection. Significantly associated clinicopathological features with recurrences included patients who were male, large lesions (>90 mm), presence of root resorption, cortical perforation, mural subtype, and retention of associated teeth. In conclusion, decision making in the management of unicystic ameloblastoma should be based on the clinicopathological features and not be solely based on the histopathological subtype. Enucleation followed by application of Carnoy's solution and burring of the peripheral bone margin was demonstrated to be the least invasive method with an acceptable low recurrence rate.

Metastatic amelanotic melanoma to the mandible mimicking benign odontogenic neoplasm.

Metastatic lesions to the jaws are rare and represent about 1% of all malignancies in the oral cavity. They are not usually considered as part of the differential diagnosis due to their paucity and unusual clinico-pathological features leading to diagnostic challenges. We report on a rare case of metastatic melanoma to the anterior mandible in a 58 year old Caucasian female that mimicked benign odontogenic tumour. The lesion posed a diagnostic challenge as it clinically and radiographically presented as a well-defined radiolucency with minimal bony destruction and no pigmentation or ulceration of the oral mucosa. Histological examination was also challenging as the lesion was not part of the differential diagnosis and a process of exclusion was employed to narrow the possible diagnoses. The tumour cells were immunoreactive with S100, HMB45 and SOX10 which raised the suspicion of melanoma. MELAN A confirmed the diagnosis of amelanotic melanoma. The patient underwent resection of the mandible with neck dissection and fibula free flap reconstruction. In conclusion, clinicians should always keep in mind that melanoma has diverse clinico-pathological presentations and hence is known as "the great mimicker". It should always be suspected in patients who present with unusual lesions in the jaws that do not conform to other more common odontogenic neoplasms.

Protocol for management of odontogenic keratocysts considering recurrence according to treatment methods.

The management of odontogenic keratocysts (OKC) remains a hotly debated topic in oral and maxillofacial surgery. Despite numerous studies and systematic reviews on treatment options, there is a lack of consensus and no accepted protocol on the management of OKC. Hence, the aim of this study was to briefly summarize all large systematic reviews in the literature on the management of OKC and formulate an evidence-based management protocol. Data from five large systematic reviews were combined to calculate the mean recurrence rate for each technique. Decompression followed by enucleation along with adjuvant methods such as application of Carnoy's solution and peripheral ostectomy can result in very low recurrence and is an acceptable first line treatment. The surgical approach should be determined by lesion size, patient age, proximity to vital structures, accessibility, soft tissue/cortical perforation, and if the lesion is recurrent.

Residual cyst of the jaws: A clinico-pathologic study of this seemingly inconspicuous lesion.

OBJECTIVES: Residual cysts are relatively rare inflammatory cysts of the jaws. They are essentially radicular cysts without the presence of the offending dentition. These lesions have the ability to destroy bone within the jaws without any symptoms. Moreover, they can mimic more aggressive cysts and tumours on radiographs. The aim of this study was to describe the clinico-pathological features of residual cysts in order to discern them from other cystic lesions as well as analyse their management and recurrence patterns. MATERIALS AND METHODS: Sixty-four histopathologically confirmed residual cysts were analysed based on their clinical, radiological and histopathological features. Their management and follow-up were also noted. RESULTS: The majority of lesions presented in elderly (46.8%), edentulous patients (60.9%) and were most commonly found in the posterior regions of the mandible (51.6%). Clinico-pathological features that aided in their diagnosis included long-standing history with slow growing swelling and presence of well-defined, unilocular cystic lesion associated with previously extracted dentition. Enucleation was a successful method in the management of residual cysts with very low recurrence rate (1.6%). Two patients (3.1%) developed squamous cell carcinoma from the cyst lining. CONCLUSION: Residual cysts should be high on the list of differential diagnosis when elderly, edentulous patients present with cystic lesions in the jaws compared to dentate patients (P<0.01). All lesions should by biopsied and sent for histopathological examination along with radiological correlation as they have the potential to transform into primary intra-osseous squamous cell carcinoma with devastating consequences to the patient.

Osteopetrosis complicated by osteomyelitis of the maxilla: A rare case report and review of the literature.

Osteopetrosis is a rare hereditary bone disorder that results in an increase in bone density due to gene mutations and osteoclastic dysfunction. This may lead to cranial nerve compression, bone fractures and osteomyelitis. Osteomyelitis of the maxilla is rare even in osteopetrosis patients. We report on a case of a 25-year-old male who presented with multiple episodes of osteomyelitis of the maxilla following dental extractions. The patient was initially managed with the incision and drainage of an acute infection, and intravenous amoxicillin-clavulanic acid. This was followed by the debridement of necrotic bony margins and packing with bismuth iodoform paraffin paste (BIPP) as well as long-term clindamycin. Once osteomyelitis was clear, the primary closure was achieved with a buccal advancement flap and supported by an acrylic obturator. Challenges in the management are highlighted, including preparing for a surgical intervention a patient with chronic low hemoglobin levels and a lack of healthy bony margins in the maxilla. The literature is also reviewed for similar cases.

Dental development in a sample of South African HIV-positive children.

AIMS: While oral soft tissue manifestations associated with HIV-infection in children are well documented, few studies have investigated the dental development of this group. The aim of this study was to assess dental development in a sample of HIV-positive children in comparison with an age-matched HIV-negative control group. METHODS AND RESULTS: The sample comprised 44 HIV-positive children and 44 HIV-negative children matched for age, gender, and ethnicity. An orthopantomograph (OPG) of each patient was assessed in order to calculate the dental age. The mineralization stages of teeth were used to calculate the dental age using tables formulated by Phillips and van Wyk-Kotze for this grouping. Results showed that dental development for both groups were similar to the dental age-related tables. HIV-positive children between 8 and 10 years of age showed significantly advanced dental development (p = 0.04). HIV-positive females showed significant advancement in dental age as compared to their chronological ages. Thirty-six (81.8%) HIV-positive children were on antiretroviral (ARV) drugs. CONCLUSION: HIV-positive children presented stages of dental development in accordance with their chronological ages and in tandem with that of the HIV-negative controls.

The imaging characteristics of odontogenic myxoma and a comparison of three different imaging modalities.

OBJECTIVE: To report the imaging characteristics of odontogenic myxoma (OM) and compare the different imaging modalities used. STUDY DESIGN: The radiological images of 33 OM cases were retrospectively analyzed. The radiographs were severally examined to describe the features of OM as seen on conventional radiographs (CRs), computed tomography (CT) scans, and magnetic resonance images (MRIs). RESULTS: MRI was effective in displaying the true extension and contents of OMs. CT scans demonstrated the extensions of OMs, expansion, growth pattern, and rendered it possible to compare density of OM with that of surrounding muscles. Assessment of CRs revealed great limitations about the diagnostic values and failed to display important features. CONCLUSIONS: All 3 radiographic techniques, conventional radiography, CT, and magnetic resonance imaging (MRI), have inherent advantages and disadvantages; however, all 3 should be routinely used in the diagnosis of OM. The results of CT and MRI can accurately reveal margins of tumors and greatly aid in diagnosis.

Keratocystic odontogenic tumor: a recurrence analysis of clinical and radiographic parameters.

OBJECTIVE: The aim of this study was to analyze the clinical and radiologic features of keratocystic odontogenic tumors (KCOT) and their recurrence patterns. STUDY DESIGN: The authors undertook a retrospective analysis of 145 histopathologically proven KCOT. Recurrence was analyzed for age, sex, site, size, radiographic appearance, treatment, and association with nevoid basal cell carcinoma syndrome (NBCCS). RESULTS: The mean age at presentation was 34.5 years, with a male predilection. Most KCOT (75.2%) were located in the mandible, with the posterior regions being most commonly affected. Radiographically, the majority of KCOT were unilocular (71.0%) in appearance, and 16.5% had scalloped margins. There was no significant association of recurrence rate with sex, site, size, radiographic appearance, and treatment. However, KCOT had significantly higher recurrence associated with age (P < .01) and NBCCS (P = .001). CONCLUSIONS: Most clinical and radiologic features of KCOT were similar to earlier reports. Recurrence was significantly associated with second and eighth decades of life and NBCCS.