Metastases to the oral cavity.

Metastatic spread to the oral cavity of a malignant neoplasm is a rare yet important sign of advanced systemic malignant disease. This manuscript briefly describes the metastatic process and highlights the most common neoplasms that metastasise to the oral cavity as well as their clinical and radiological presentations. The role of the patients' history in suspecting metastatic disease and the importance of a microscopic diagnosis is emphasised.

Medial tongue cleft associated with intraoral hamartoma--case report and review of literature.

A newborn female was referred with the following clinical symptoms: median tongue cleft, palate cleft, ankyloglosson, sublingual intraoral hamartoma and palatal intraoral hamartoma. Magnetic resonance imaging showed a subcutaneous cyst overlying the manubrium sterni. Genetic investigation (chromosome analysis) showed no aberrations and/or variations. The quick growth of the intraoral hamartoma required an excision at the age of 3 months. Under general anaesthesia the intraoral hamartoma was excised and the median tongue cleft was closed. Median tongue clefts are reported to be only associated with orofacial digital syndromes type I, II, IV and VI. If the clinical appearance is described without any association to an orofacial syndrome, the Tessier 30 cleft definition could be used as the best explanation of the symptoms. This is the first description of a combination of tongue cleft, palate cleft, intraoral hamartoma and subcutaneous cyst overlying the manubrium sterni. The clinical symptoms of this patient can be described best as a mild form of an orofacial digital syndrome type II or variation of a Tessier cleft No. 30.

Enamel dysplasia with hamartomatous atypical follicular hyperplasia (EDHFH) syndrome: suggested pathogenic mechanisms.

The syndrome of enamel dysplasia with hamartomatous atypical follicular hyperplasia (EDHFH) is an unusual syndrome and is unique to black South Africans. Major criteria for the syndrome are enamel dysplasia with generalized amelogenesis imperfecta-like features and atypical hyperplastic dental follicles with microscopic features of central odontogenic fibroma WHO-type (follicle analogue) attached to the crowns of multiple impacted teeth. Minor features of some cases are anterior open-bite malocclusion, supernumerary teeth, pulpal calcification, aberrant roots with hypercementosis, and hypodontia. The pathogenic mechanisms that lead to the development of EDHFH are unknown. We speculate that faulty synthesis of enamel matrix proteins may interfere with enamel formation and play a role in the generalized enamel hypoplasia described in this syndrome. Alterations in inductive signalling by the odontogenic epithelium mediated by enamel matrix proteins may explain the development of the follicle analogues, the root hypercementosis and the presence of dysplastic cementum deposition juxtaposed to odontogenic epithelium in the gingival overgrowth. Thus, alterations in the function of enamel matrix protein function, may be the common denominator responsible for the development of the EDHFH phenotype.

Plasma cell gingivitis: does it exist? Report of a case and review of the literature.

Plasma cell gingivitis is an uncommon inflammatory condition of uncertain aetiology. It is characterized clinically by enlarged erythemathous gingivae, a velvety texture and histopathologically by a dense plasmacytic infiltrate in the lamina propria. We present a case of a 19-year-old female who had what appeared to be plasma cell gingivitis. The clinical and histopathological differential diagnosis of plasma cell gingivitis is discussed and an argument is presented raising certain doubts whether plasma cell gingivitis is a distinct clinicopathological entity or not.

Alveolar bone necrosis and spontaneous tooth exfoliation in an HIV-seropositive subject with herpes zoster.

Herpes zoster in the distribution of the maxillary and mandibular divisions of the trigeminal nerve is characterized by painful vesicular eruptions of the skin and oral mucosa in the distribution of the affected nerves. Oral complications may occur, including post-herpetic neuralgia, devitalization of teeth, abnormal development of permanent teeth, root resorption and periapical lesions. In cases where necrosis of the alveolar bony process occur it may be preceded or accompanied by spontaneous exfoliation of teeth. This usually follows the resolution of the acute phase of HZ and is more prevalent in HIV-seropositive than in HIV-seronegative subjects. A case of HZ of the trigeminal nerve in an HIV-seropositive subject, with complications of necrosis of alveolar bony process, external root resorption and tooth exfoliation is presented and the literature of HIV-associated HZ is reviewed.

Enamel dysplasia with hamartomatous atypical follicular hyperplasia: review of the literature and report of a case.

This article documents an additional case of a rare syndrome, reported only in black persons in South Africa. It is characterised by hamartomatous atypical follicular hyperplasia with central odontogenic fibroma (WHO-type)-like features attached to multiple impacted teeth, and with generalized enamel dysplasia showing features of hypoplastic amelogenesis imperfecta. Other features associated with the syndrome, but not present in all reported cases, include open-bite malocclusion, gingival overgrowth, hypodontia, pulpal calcifications and aberrant root formation of the unerupted teeth. Our present case shows the additional feature of impacted supernumerary teeth. As we cannot find any reports in the literature of the occurrence of amelogenesis imperfecta-like enamel dysplasia associated with hamartomatous follicular hyperplasia showing the features of WHO-type central odontogenic fibroma, with or without the additional features mentioned above, we propose to name this syndrome Enamel Dysplasia with Hamartomatous atypical Follicular Hyperplasia (EDHFH) syndrome.

Necrotizing gingivitis of Kaposi sarcoma affected gingivae.

Necrotizing gingivitis and oral Kaposi sarcoma are common concomitants of HIV infection and both are regarded as indicators of HIV infection. Their simultaneous appearance in an HIV seropositive subject therefore, should be relatively common; but other reports documenting such cases could not be found. This article documents an uncommon case of necrotizing gingivitis superimposed on Kaposi sarcoma-affected gingiva, occurring in a patient with chronic periodontitis. The nature of necrotizing gingivitis and Kaposi sarcoma and the possible differential diagnosis of the periodontal attachment loss are discussed.

The role of DNA ploidy and Ki-67 in the grading of mucoepidermoid carcinomas.

BACKGROUND: The grading of mucoepidermoid carcinomas (MEC) is based on subjective microscopic evaluation of the prevalence of cell types as well as features of atypia and aggressiveness. Our study was aimed at evaluating the role of high-resolution DNA flow cytometry and Ki-67 expression in the grading of MEC. MATERIALS AND METHODS: Fifty-five cases of intraoral and major salivary gland tumours, diagnosed as MEC, were retrieved and the grading system proposed by Brandwein et al. applied. RESULTS: Forty-nine per cent of our sample was graded as high, 35% as intermediate and 16% as low. Eighty-nine per cent of the high-grade MEC showed aneuploid DNA cell populations, while 88% of the diploid tumours were graded as intermediate or low. The mean Ki-67 positivity was significantly different between the high and intermediate grade tumours and between the aneuploid and diploid tumours. CONCLUSION: This study showed that high-resolution DNA flow cytometry of archival paraffin-embedded tissue is accurate in the grading of MEC and can be used with Ki-67 expression as an additional diagnostic tool.

The role of ivory in the survival of the African elephant.

The unique chequered pattern of polished ivory has created a perverted commercial demand for elephant tusks. The morphologic basis of the pattern, which makes ivory a sought after product for the manufacturing of works of art, is discussed. Chemical analyses of ivory holds great potential in tracing the source of illegally harvested tusks and exposing poorly managed elephant sanctuaries. The impact of uncontrolled ivory hunting on the population genetics of the African elephant is briefly reviewed.

Prevalence of EBV in oral squamous cell carcinomas in young patients.

BACKGROUND: Recent studies reported a difference in the age distribution of oral squamous cell carcinoma (OSCC) between Black and White South Africans with OSCC more prevalent in Black patients under the age of 50 compared to Whites. MATERIALS AND METHODS: Paraffin embedded blocks of OSCC were divided into two groups: one with a mean age of 56.2 years and the second group all younger than 40 years of age. A control group of 30 non-neoplastic intraoral lesions were selected. A standard PCR reaction was used to amplify the BAM H1 W-fragment of the EBV. RESULTS: EBV DNA was demonstrated in 11/45 (24%) cases from the first group and in 11/45 (24%) cases from the second group. EBV DNA was present in 11/30 (37%) cases from the control group. CONCLUSIONS: This study showed that the prevalence of EBV in OSCC was not influenced by the age of the patient.

Correlation between p53 gene mutation, p53 protein labeling and PCNA expression in oral squamous cell carcinomas.

BACKGROUND: The prevalence of oral squamous cell carcinoma (OSCC) among the Black community in South Africa is unacceptably high. The association between p53 protein, and PCNA overexpression and the presence of p53 gene mutations was evaluated. MATERIALS AND METHODS: One hundred and ten formalin-fixed, paraffin-embedded blocks of OSCC were selected for immunohistochemical studies for p53 protein and PCNA expression using the DO-7 and PC10 monoclonal antibodies, respectively. DNA was extracted from fifty-five blocks and exons 5 to 9 of the p53 gene were amplified with nested primers, thereafter sequencing was performed to confirm the presence of mutations detected by single stranded conformational polymorphism. RESULTS: Fifty-six cases (51%) showed p53 expression, while fourteen mutations (25%) were detected. A significant difference was found between the PCNA index in p53 positive and p53 negative tumors while the mean PCNA index for the tumors with p53 mutations was not significantly different from the tumors without mutations. CONCLUSIONS: No association between p53 protein overexpression and p53 gene mutations could be demonstrated.

Early development of the tush and the tusk of the African elephant (Loxodonta africana).

This early development was studied from a serial histological sections of eight elephant embryos with masses varying between 1 and 240 g. The tush and the tusk develop from one tooth germ in a deciduous to permanent tooth relation. In order to study the mineralization of the dental organ of the tush and cap and bell stage of the tusk, embryos older than 3-months' gestation (weighing more than 250 g) would be required.

Histogenesis of the chequered pattern of ivory of the African elephant (Loxodonta africana).

This study aimed to propose a hypothesis on the events which lead to the development of the characteristic chequered pattern of elephant ivory. Twenty fragments of ivory and six elephant tusks were obtained through the National Parks Board of South Africa. Polished surfaces were prepared in sagittal and longitudinal planes and the characteristics of the distinctive chequered pattern described. Light- and electron-microscopical techniques and image analyses were employed to determine the morphological basis of the pattern and to describe the spatial distribution, density and morphology of the dentinal tubules. These investigations showed that the distinctive pattern was the result of the sinusoidal, centripetal course followed by dentinal tubules. The apical, slanted part of the sinusoidal curve is the result of the centripetally moving odontoblast, which, during formation of ivory, progresses towards the centre of the tusk on a decreasing circumference. It is suggested that this leads to cell crowding, increased pressure between odontoblasts and subsequent apical movement of their cell bodies, cell degeneration and fusion. Odontoblastic degeneration and fusion probably relieve the pressure between the crowded odontoblasts by reducing their numbers and the remaining odontoblasts now orientate their centripetal course towards the tip of the tusk, thereby forming the anterior-directed part of the sinusoidal path of the tubule. As odontoblasts progress centripetally the diameter of the pulpal cavity decreases further and the processes of apical movement, fusion and degeneration of odontoblasts are repeated. This occurs until the pulpal cavity is obliterated.

Morphology of the deciduous tusk (tush) of the African elephant (Loxodonta africana).

The tusk of the African elephant is preceded by a deciduous tooth generally known as the tush. Tushes from nine elephant fetuses and six calves younger than 1 year were exposed by dissection and described morphologically. All tushes consisted of a crown, root and pulpal cavity, the formation of which is completed soon after birth. They reached a maximum length of 5 cm, appeared not to erupt through the skin and were pushed aside and resorbed during enlargement of the distally located primordium of the tusk. Dental enamel, which covered the crown, could easily be removed and consisted of rods with an interwoven arrangement; the dentine-enamel junction was flat. Cellular cementum extended for variable distances over the crown and the dentine was tubular in nature. Although the tush apparently has no function, it provides the anlage and orientation for the development of its permanent successor.

Amino acid composition of dentine in permanent human teeth.

Dentine of permanent mandibular incisors from nine individuals was hydrolysed and the amino acid composition determined by ion-exchange chromatography against a standard calibrant of 41 amino acids. Nineteen amino acids were detected, including small quantities of 1-methylhistidine and asparagine, two amino acids whose existence had apparently not been recorded before in human dentine. The total content of hydroxylysine plus lysine varied between 2.6 and 3.3 residues per 100 (SD, 0.74) in different teeth, which therefore did not support previous studies that had proposed a constant total value. This and other quantifiable differences between present and previous findings may be the result of the different methods and the influence of dietary and other regional factors on dentinogenesis.

Geographic variations in the composition of ivory of the African elephant (Loxodonta africana).

Tracing the source of origin of illegal ivory will contribute to the identification of poorly managed game parks and facilitate steps taken to prevent the African elephant from becoming extinct. This study was aimed at establishing a database on the composition of ivory obtained from elephant sanctuary areas in Southern Africa. Fragments of elephant ivory from seven geographically distinct areas in South Africa, Namibia and Botswana were analysed for inorganic and organic content. A total of 20 elements was detected in the inorganic fraction of ivory, some in concentrations as low as 0.25 microg/g. The concentrations of calcium, phosphate, magnesium, fluoride, cobalt and zinc showed statistically significant differences (p < 0.007) between ivory obtained from different regions. Analyses of the organic fraction identified 17 amino acids. Ivory from arid regions showed significantly lower proline plus hydroxyproline content and under-hydroxylation of lysine residues. This study indicates that chemical analyses of ivory could be beneficial in tracing the source of illegal ivory.

Langerhans cells and human papillomaviruses in oesophageal and laryngeal carcinomas.

Human papillomavirus (HPV) infection is implicated in squamous cell carcinogenesis. Oesophageal carcinoma has a high incidence in certain geographical regions and, using different methods of detection, HPVs have been found in these tumours. HPV 6 and 11 are frequently detected in laryngeal papillomas, benign lesions which rarely become malignant. HPVs have been detected in squamous carcinoma of the larynx but more frequently, especially HPV 16, in verrucous carcinomas a distinct variant of squamous carcinoma. An increased density of Langerhans cells, important in immunosurveillance in squamous epithelium, has been associated with a more favourable patient prognosis in laryngeal and other carcinomas.

A retrospective analysis of 367 cystic lesions of the jaw--the Ulm experience.

Out of 846 cyst-like lesions of the jaws, 367 cases were retrieved from the files of the Department of Oral and Maxillofacial Surgery at the University of Ulm and classified according to the new World Health Organization's classification for odontogenic tumours and cysts. Radicular and residual cysts comprised 56.9%, dentigerous cysts 21.3%, odontogenic keratocysts 10.6%, unicystic ameloblastomas 4.1%, nasopalatine duct cysts 2.7%, glandular odontogenic cysts 1.6% and paradental cysts, traumatic bone cysts, calcifying odontogenic cyst and lateral periodontal cyst each less than 1% of the sample. Nearly one third of the specimens were obtained from military patients; despite an expected bias towards young males, unicystic ameloblastomas presented one and a half decades later than is generally reported.

Multiple myeloma presenting as localized expansile jaw tumour.

Myelomatous involvement of the maxilla is an exceptionally rare occurrence, and the presentation of the lesion as an expansile jaw bone tumour has not been reported. 2 cases, one with a maxillary lesion, the other with a mandibular lesion are presented, both of which illustrate gross bone expansions. Additionally, 1 case presented with a rare biclonal IgG kappa and IgG lambda light chain secreting myeloma. Relevant clinical, immunological, histological, biochemical and histochemical features are presented and discussed, and suggestions pertaining to surgical management made.

Gigantiform melanotic neuroectodermal tumor of infancy.

Melanotic neuroectodermal tumor of infancy is a rare neoplasm of possibly neural crest origin, and it predominantly occurs in the premaxillas of infants less than 12 months old. Generally, the treatment of this benign pigmented lesion is conservative surgical excision. Long-term follow-up is imperative inasmuch as local recurrence and malignant transformation have been reported. A case with exceptional clinical features involving a 7-month-old child is presented.