Holes in the head: parietal foramina, a developmental anomaly seen during a routine orthodontic assessment

Parietal foramina (Catlin marks) are developmental anomalies which affect approximately 1 in 25,000 people. They are thought to be inherited as an autosomal trait and may be associated with other skeletal anomalies such as cleft lip or palate. The majority of enlarged parietal foramina are usually completely asymptomatic.

Demographics of HIV-infected persons attending a dental clinic

The demographics of 147 HIV-infected persons attending a special care dental clinic in South West England are reported. The majority of attendants were homosexual/bisexual males, reflecting the UK epidemiology of HIV disease at the time of study. There was a substantial rise in patient numbers from 1988 onwards but patients often did not reveal their route of HIV acquisition or increasingly had acquired HIV disease via heterosexual routes. Patients were usually referred for routine dental treatment, not HIV-related oral disease. The HIV-infected patients generally attended the clinic irregularly, despite being offered many appointments. It is concluded that most patients with HIV disease attend clinics for routine dental care, yet many may be unable or unwilling to attend regularly.

Emergence of azole drug resistance in Candida species from HIV-infected patients receiving prolonged fluconazole therapy for oral candidosis

We examined the effect of different fluconazole treatment regimens on the emergence of azole drug resistance among Candida species recovered from the mouths of 54 HIV-infected individuals. Patients were assigned to one of three treatment groups depending on their history of oral candidosis and fluconazole use. Mouthwashes obtained at regular intervals were cultured and isolates identified using standard methods. Antifungal broth micro-dilution tests were performed to determine IC30s of fluconazole and ketoconazole. Sixty-four Candida albicans isolates from 20 patients with no evidence of oral candidosis who had not received fluconazole all had IC30s of < or = 4 mg/L. Thirty-four (83%) of 41 C. albicans isolates from ten patients receiving intermittent, short-term fluconazole treatment for oral candidosis had IC30s of < or = 4 mg/L, but only two isolates (5%) had IC30s > or = 64 mg/L. In contrast, 26 (40%) of 65 C. albicans isolates from 15 patients given long-term fluconazole (50-200 mg/day or 150 mg/week) were classified as resistant having IC30s of fluconazole of > or = 64 mg/L. Ten of these 26 fluconazole-resistant isolates were susceptible to ketoconazole with IC30s of < or = 4 mg/L suggesting azole drug cross-resistance is not inevitable. Tests on multiple colonies from individual isolation plates showed that it was not unusual to obtain differing IC30 values, indicating that a sweep inoculum is essential if resistance is to be detected. Nine (60%) of the 15 patients given long-term fluconazole harboured isolates of C. albicans that were resistant to fluconazole at some time during the study period. All had low CD4 counts and were approaching the final stage of their illness. Three patients on long-term treatment had resistant organisms at the outset of the study; in the remainder, resistant strains emerged during the study period. In six of the nine cases, emergence of resistance in vitro correlated with persistent clinical signs of oral infection. Thirty-six isolates of Candida species other than C. albicans were also recovered from patients receiving long-term fluconazole and 29 (81%) of these had IC30s of > or = 64 mg/L. Our experience with C. albicans in patients with HIV infection, suggests that the long-term azole drug use may be an important factor in the development of fluconazole resistance as such resistance was rare and transient in patients on intermittent short-term treatment.

Oral features of a family with benign familial neutropenia

The oral features of three members of a family with familial benign neutropenia (a mother and two children) are detailed. Prepubertal periodontitis, oral ulceration, and angular stomatitis were the principal features.

HIV-salivary gland disease. Salivary scintiscanning with technetium pertechnetate

The salivary disease in two patients with human immunodeficiency virus infection was investigated by technetium pertechnetate scintiscanning. Although there was good histologic evidence of benign lymphoepithelial disease, scintiscanning failed to delineate any salivary lesions. Technetium pertechnetate scintiscanning seems to be of little value in the detailed investigation of salivary disease in human immunodeficiency virus infection, though gallium scanning can help. Fine needle aspiration or biopsy remain the main diagnostic tools.

Complications of dental surgery in persons with HIV disease

Post tooth extraction infective complications have occasionally been described in HIV-infected persons. However, there is little objective data as to the frequency of this and the need for antibiotic prophylaxis. Similarly the frequency of postextraction bleeding in patients infected with HIV, who may have thrombocytopenia, is unknown. In the present study the frequency of postextraction complications has been investigated in a group of 38 persons at stages 2 to 4 of HIV infection and 26 matched subjects from patients groups commonly at risk of HIV infection but not seropositive. During 40 clinical procedures in HIV-infected patients, 100 (range 1 to 23, median 1) teeth were extracted. Three episodes of delayed postextraction healing were recorded. During 30 procedures in the non-HIV-infected persons, 68 (range 1 to 5, median, 2) teeth were extracted, and two episodes of delayed postextraction healing were recorded. These differences were not significant. Only one HIV-infected patient had an episode of severe postextraction bleeding: this was a hemophiliac who bled despite receiving factor VIII prophylaxis. The bleeding occurred 7 days after the extraction and ceased with tranexamic acid and additional factor VIII. No control subject had severe postextraction hemorrhage. It is concluded that postextraction complications are uncommon in HIV-infected patients and that routine antibiotic prophylaxis is not indicated.

Recognition of oral lesions of HIV infection. 3. Gingival and periodontal disease and less common lesions

This is the last of a series of three articles on the recognition of oral lesions of HIV infection. It deals with the less common, and some rare lesions.

Recognition of oral lesions of HIV infection. 1. Candidosis

Oral problems are often the first significant clinical manifestations of infection with human immunodeficiency virus (HIV). Their early recognition affords the best opportunity for effective therapeutic intervention of HIV infection and opportunistic infections, as well as for oral health education in order to avoid future problems. This also provides optimal time for behaviour modification and coming to terms with the psychosocial consequences of HIV disease. This series of three articles presents a pictorial review and update on the oral manifestations of HIV infection.

The lateral medullary syndrome

The lateral medullary syndrome is a rare syndrome resulting from a cerebrovascular accident involving part of the medulla oblongata with consequent loss of pain and temperature sensation in the orofacial region, loss of taste, and palatal palsy and loss of gag reflex, together with Horner's syndrome and ataxia. A case is presented and the literature reviewed.

The expression of anchorage independence by malignant rat oral keratinocytes after colony formation in vitro and tumour formation in vivo

The expression of anchorage independence in malignant oral epithelial cells retrieved from colonies formed in agarose and tumours formed in athymic mice was examined. The original epithelial cell lines were derived from lingual and palatal squamous cell carcinomas induced in rats by the carcinogen 4-nitroquinoline N-oxide. The capacity to express anchorage independence varied considerably between the original cell lines and essentially increased with passage in culture. In three out of four colony-derived subpopulations, the colony-forming efficiency was significantly greater than that of the original cell lines. Xenograft subpopulations expressed higher colony-forming efficiencies than their original counterparts in only two of five cell lines. Undifferentiated tumour xenografts resulted in more homogeneous tumour-derived subpopulations, in contrast to the more heterogeneous cell lines from well-differentiated tumours. The findings demonstrate functional diversity within and between malignant rat oral epithelial cell lines and their colony- and xenograft-derived subpopulations.

The effect of 3T3 fibroblasts on the expression of anchorage independence and cornification of oral keratinocytes

This study examined the effect of 3T3 fibroblasts on the expression of anchorage independence and the degree of cornification in early cultures of three carcinoma-derived epithelial cell lines (R59, R63a, R63b) and in one cell line derived from non-malignant dysplastic epithelium where there was no evidence of invasion (R66a). The epithelial cell lines originated from the palatal (R63a, R66a) and the lingual (R59, R63b) mucosa of rats that had been painted with the carcinogen 4-nitroquinoline N-oxide. In the absence of 3T3 fibroblasts, progressive culture resulted in an increase in the colony forming efficiency (CFE) of R63a, R63b and R59 and a decrease in the percentage of cornified cells in all cell lines. 3T3 fibroblasts caused a decrease in the CFE and the degree of cornification in the 3T3-dependent cell line (R63a), particularly at the lower passages, but these parameters remained essentially unchanged by 3T3 fibroblasts in the 3T3-independent cell lines (R59, R63b). 3T3 fibroblasts did not influence the cornification of R66a and this cell line remained anchorage dependent throughout the study. The results suggest that in malignant cell lines characterised by being independent of 3T3 fibroblasts (R63b, R59) the CFE was inversely correlated to the degree of cornification. However, in the malignant cell line showing a greater dependence on support (R63a) the relationship between CFE and cornification was unclear because these parameters may have been modulated by the presence of 3T3 fibroblasts. The cell line from dysplastic non-invasive tissue (R66a) differed from its malignant counterparts in the fact that CFE and cornification were unaffected by 3T3 fibroblasts despite previous studies showing a dependence on mesenchymal support.

Orofacial manifestations of a group of British patients infected with HIV-1

The orofacial manifestations of 44 HIV-infected individuals from the South West of England are reported. Oral candidiasis, periodontal disease and cervical lymphadenopathy were the most commonly observed disorders although hairy leukoplakia was also present in 15% of patients. The orofacial features of this group of British patients are similar to those of HIV-infected individuals from other parts of Europe, North America and Scandinavia.

Transformation of oral keratinocytes in vitro by 4-nitroquinoline N-oxide

Normal rat oral keratinocytes have been transformed with the carcinogen 4-nitroquinoline N-oxide (4NQO) in vitro. The morphology, growth characteristics, ability to grow without anchorage and tumorigenicity in athymic mice was examined in 12 selected cell lines. Each of the lines could be assigned to one of two general groups. The first group of cell lines although showing some morphological signs of transformation and the ability to be subcultured beyond passage 15 were not anchorage independent or able to form tumours in athymic mice. The second group of cell lines showed distinct signs of morphological transformation, could be serially subcultured without 3T3 feeder cells, were anchorage independent and tumorigenic in athymic mice. Anchorage independence was more common at higher passages and with increased 4NQO treatment and correlated well with a decreased reliance on 3T3 feeder cell support. The anchorage-independent phenotype was closely associated with the ability to form tumours in athymic mice. This same sequence of phenotypic changes has been demonstrated in rat oral keratinocytes after 4NQO treatment in vivo indicating that during carcinogenesis, cell populations progress through the same stages whether proliferation occurs in vitro or in vivo. There is some evidence to suggest, however, that the time interval between stages may be altered when carcinogenesis takes place in vitro.

The inter-relationship between anchorage independence and tumorigenicity in early cultures of oral keratinocytes

This study examines the expression of anchorage independence and tumorigenicity in early cultures of oral rat keratinocytes. The epithelial cell lines originated from the palatal and the lingual mucosa of rats that had been painted with the carcinogen 4-nitroquinoline N-oxide. The colony forming efficiency (CFE) in gel culture of the cell lines derived from five squamous cell carcinomas of the tongue and palate predominantly increased with passage in culture. Carcinoma-derived cell lines that had a relatively high CFE (greater than 2.5%) formed tumours when transplanted to athymic mice, but cells in which the CFE was less than 2.5% were non-tumorigenic. Keratinocytes from a dysplastic palatal lesion were immortal, anchorage dependent and non-tumorigenic. A lingual papilloma cell line consistently expressed a very low CFE but was tumorigenic at the higher culture passages. The results show that the routine passage of cells in culture leads to the emergence of the anchorage independent and tumorigenic phenotypes in keratinocytes of malignant origin and, further, suggest that anchorage independence and tumorigenicity may exist as distinct phenotypes, with anchorage independence preceding tumorigenicity.

Characterization of malignant rat keratinocytes in culture following the induction of oral squamous cell carcinomas in vivo

An in vivo model of oral epithelial carcinogenesis in rats has been established successfully in cell culture. Oral carcinomas of the tongue and palate were induced in Sprague-Dawley male rats by painting their palates three times weekly for 7-8 months with 0.5% (w/v) 4-nitroquinoline-N-oxide. Oral keratinocytes from malignant and untreated control tissues were cultivated using 3T3 fibroblast support. Both the normal and malignant cells stained positively with an anti-human keratin polyclonal antibody but malignant keratinocytes were heterogeneous with regard to cell size, shape and intercellular packing, unlike the regular organization of the normal cultures. Malignant keratinocyte cultures differed markedly from their normal counterparts by an increase in their growth rate, the capacity for serial cultivation to the 25th passage (to date) and independence of 3T3 fibroblast support. In contrast, cultures established from healthy tissue showed signs of senescence usually by passage 4 and were totally reliant on 3T3 fibroblast support for growth. Malignant keratinocytes expressed anchorage independence when cultured in a semi-solid medium and gave rise to tumour formation in athymic mice. The development of this specialized cell culture system substantially increases the potential of the rat 4NQO model to investigate the pathogenesis of oral squamous cell carcinomas.