A model for design of online health professions education faculty development courses in sub-Saharan Africa.

The design of faculty development courses requires a contextually aware theoretical foundation. Therefore, the study aimed to determine the feasibility of a specific conjecture map as a model for designing online health professions education faculty development courses in sub-Saharan Africa through a heuristic evaluation approach. The authors hypothesise that using heuristic evaluation strengthens an educational model's theoretical basis and feasibility.Twenty-five health professions educators from nine sub-Saharan African countries participated in this multi-phased study. In the first phase, the participants completed a survey evaluating the model and the accompanying author-generated heuristics. Then, participants' recommendations were used to make revisions. In the subsequent phase, participants reviewed these revisions and commented on the feasibility of the model within their local context.All six heuristics were revised following the initial phase, where 80 problems had been identified. Upon revision, the model was deemed feasible by all except one participant. There was a strong relationship and inter-rater agreement of feasibility between 0.84 and 0.95 regarding the model's practicality, demand, acceptability, and adaptability. Revisions to the final model and guidance documents incorporated all changes the participants recommended, confirming the model's feasibility.Theoretical models are often developed through a top-down approach, omitting the practice-based considerations that could change the formulation of the model. This study demonstrates the convergence of a theoretical and process model with theoretical, expert and end-user data triangulation. Further research is needed to test this empirically developed model.

Clinical correlates of oral malodour in a population of patients attending a preventive clinic in Pretoria, South Africa.

AIM: This study investigates the occurrence of oral malodour in an adult dental clinic population in Pretoria, South Africa, and the clinical parameters associated with the condition. METHODS: Data collected from new patients (n=896), examined by oral hygiene students under supervision of instructors, between January - October 2004, were retrospectively analysed. Subjects self-reported their medical history and smoking status. Caries experience, plaque index, pocket depths, bleeding on probing (BOP), tongue coating status, and oral hygiene practises were recorded. Malodour was diagnosed using the halimeter (> or = 120ppb) and an organoleptic measurement (0-5 point scale) of > or = 3. Data analysis included chi-square, t-tests and logistical regression. RESULTS: 15.1% presented with organoleptically-determined malodour and 20.9% presented with malodour detected by the use of the halimeter. Irrespective of the diagnostic tool used, tongue coating, increased plaque levels and BOP were associated with an increased likelihood for oral malodour, while regular flossing reduced the likelihood of presenting with the condition. Periodontitis was associated with oral malodour when applying organoleptic ratings, but not with the halimeter. CONCLUSIONS: Oral malodour prevalence corresponds with values reported in developed countries. Interdental flossing was the most effective self-care practise associated with a reduced likelihood of presenting with malodour. Halimeter performance should be further investigated in relation to varying degrees of severity of periodontal disease.

Trends in dental caries prevalence, severity and unmet treatment need levels in South Africa between 1983 and 2002.

OBJECTIVES: To determine trends in dental caries prevalence, severity and unmet treatment need levels amongst South African children. METHODOLOGY: Data obtained from three National Oral Health surveys (1982, 1988/89, 1999/2002) was used. RESULTS: Prevalence of caries amongst 12-year-old children decreased from 64.4% (1982) through 54.9% (1988/89) to 41.7% (1999/2002) and the DMFT decreased significantly (p < 0.05) from 2.54 (1982) through 1.73 (1988/89) to 1.17 (1999/2002). Unmet treatment need increased from 70.5% (1982), 72.3% (1988/89) to 75.2% (1999/2002). Significant decreases (p < 0.05) were recorded in the DMFT (1982-2002) in White, 75.3%; Asian, 64.1%; Black, 49.8%; and Coloured groups, 44.8%. High levels of untreated caries (D) and very low levels of treatment (M and F) were also observed. The highest mean dmft/DMFT for 6- and 12-year-olds respectively were recorded in the coastal areas of Metro Cape (5.1/1.86); followed by Port Elizabeth (3.86/1.37) and Durban (3.42/1.33); and the lowest in the interior--Bloemfontein (2.47/0.73). CONCLUSIONS: Caries reduced significantly during the past 20 years; is more prevalent and severe amongst Coloured and Black population groups and in coastal regions compared to the interior region. Unmet treatment need in 12- and 15-year-old children increased and more than 70% of caries in 6-, 12- and 15-year-old children go untreated.

Preventable warfarin-induced birth defects: A missed opportunity?

BACKGROUND: Congenital abnormalities and pregnancy losses due to the teratogenic effects of warfarin are prevalent among the South African population. These are potentially preventable if the challenges and barriers faced by at-risk women are understood and addressed effectively. OBJECTIVES: To determine the practice, knowledge and attitudes regarding the teratogenic risks experienced by women administered warfarin. METHODS: A descriptive study was performed. Quantitative data were collected through a researcher-administered questionnaire. The target population comprised 101 women of reproductive age who received warfarin treatment and attended a single tertiary-level anticoagulation clinic. RESULTS: Patient-related challenges identified in this study are: language barriers, poor understanding of basic terminology and mathematics, poor contraceptive and family planning practices, lack of knowledge regarding the risks of warfarin in pregnancy and passive attitudes towards information attainment. CONCLUSIONS: Interventions are necessary to address the challenges in such settings. These include increased awareness of the teratogenic potential of specific chronic medications among healthcare providers, patients and the public. Standardised management protocols for women of reproductive age initiated on teratogenic medications should be implemented, including contraceptive and family planning discussions at follow-up visits. Improvement of the counselling skills of healthcare providers and the availability of translators or healthcare providers fluent in local languages could assist in risk reduction.

A rare case of heterotaxy and left ventricular non-compaction in an adult.

Heterotaxy syndrome with left ventricular non-compaction is a rare co-existence of abnormalities with unknown cause. It can be isolated with no other associations, or associated with congenital heart diseases, or it can occur with multiple other congenital abnormalities. We describe the third reported case of heterotaxy syndrome with left ventricular non-compaction presenting in an adult.

Calcium, phosphorus, fluoride, and pH levels of human dental plaque from areas of varying fluoride levels.

Plaque calcium, phosphorus, fluoride, and pH in samples obtained from 149 life-long resident children, aged from six to seven and 12 to 13 yr, from one of three naturally fluoridated communities were determined. In general, smaller amounts of phosphorus and fluoride, and larger amounts of calcium and hydrogen ions (lower pH values) are associated with smaller amounts of fluoride in the drinking water supply. Significant differences among the mean pH, fluoride, and Ca/P concentrations both in the six-to-seven- and 12- to 13-year age group were found when comparing the results of the three areas with different levels of fluoride in their drinking water supply.

Bilateral symmetrical lymphangiomas of the gingiva. A case report.

This is a report of a patient with bilateral symmetrical lymphangiomas of the mandibular gingiva which presented clinically as chronic localized gingivitis. The lesions were removed by conventional gingivectomy and have not recurred after 2 years. Both lesions were of the cavernous type and apparently confined to the gingiva. Their distribution indicates them to be developmental anomalies rather than tumors. For this reason it is felt that local excision is adequate even if the mass is incompletely removed. Anomalies should not recur in the same fashion as a tumor.

A comparative light-microscopic, electron-microscopic and chemical study of human vaginal and buccal epithelium.

The scarcity of sizeable specimens of normal oral mucosa for experimental purposes has hampered research on oral epithelium. Because large specimens of viable human vaginal mucosa are readily available and because vaginal and buccal epithelia are microscopically similar, vaginal mucosa has been used successfully to establish a human cyst model in experimental animals. The ultrastructure and distribution of keratin filaments in these epithelia are also similar, as is their permeability to water and a number of chemical substances. Therefore, if vaginal mucosa could be substituted for buccal mucosa it would expedite research on the epithelium of buccal mucosa. To strengthen further the concept that vaginal epithelium could replace buccal epithelium in certain experimental studies, the thickness of these epithelia, their patterns of surface keratinization, the presence or absence of intercellular lipid lamellae and their lipid contents were now compared. Thirty-three specimens of vaginal mucosa from postmenopausal women and 36 of buccal mucosa were investigated. To compare the thickness of the epithelial layers the number of cell layers in sections of 20 vaginal and 20 buccal mucosal specimens were counted in the three thickest and three thinnest regions of each specimen. Surface keratinization was evaluated on sections stained with the Picro-Mallory method. To demonstrate lipid lamellae two vaginal and two buccal mucosa specimens were examined electron microscopically after normal fixation and postfixation in ruthenium tetroxide. Following solvent extraction of 11 vaginal and 14 buccal epithelia, quantitative lipid analyses were performed using thin-layer chromatography. No statistically significant differences were found between the maximum and minimum number of epithelial cell layers. The patterns of surface keratinization and the distribution and appearance of the lipid lamellae in the intercellular spaces were similar. The lipid composition of the two epithelia corresponded, except for the cholesterol esters and glycosylceramides, which were higher in buccal epithelium. Ceramides for vaginal epithelium and triglycerides for buccal epithelium were not determined. Based on structural similarities, a similar lipid composition and earlier findings, it is concluded that vaginal epithelium can be used as a substitute for buccal epithelium in certain in vitro, and possibly for in vivo, studies.

Potentiometric determination of d(+)glucose, d(+)mannose or d(-)fructose in a mixture of hexoses and pentoses, by using streptococcus mutans fermentation.

A potentiometric sensor has been developed, based on selective fermentation of carbohydrates by Streptococcus mutans. This combination of bacterial action and a glass electrode responds to beta-d(+)glucose, d(+)mannose and beta-d(-)fructose over a narrow concentration range, with a response time of 4 min, and has negligible response to other hexoses and pentoses.

Bacterial electrode for L-arginine.

Streptococcus lactis bacterial cells are employed for the conversion of L-arginine into ammonia. An ammonia gas-electrode is used as a detector. The combination of bacterial action and the gas electrode responds linearly to L-arginine over the concentration range 8.0 x 10(-6) - 1.0 x 10(-3)M, with a slope of 59.0 mV/decade and is selective with respect to other l-amino acids.

Heck's disease (focal epithelial hyperplasia): a longitudinal study.

A 3-year longitudinal study on Heck's disease among school children was undertaken in 2 communities which are similar geographically, socioeconomically and ethnically. The variations in the annual prevalence rates (7% to 13%), the incidence rates per 1000 (38 to 68), the female to male ratios (1:0.4 to 1:1) and the average ages of the affected pupils did not differ between communities and from year to year. Lesions varied in number, size and duration. Some were seen only at one of the examinations, while others remained during the whole study. The majority were situated on the mucosae of the lower lips and cheeks. The prevalence of lesions amongst school children in these two communities was noticeably higher than that of another community of similar ethnicity studied earlier. The clinical behaviour of the lesions is in keeping with what is expected of some HPV infections. The relatively high prevalence rate and the anatomical distribution of the lesions indicate the infectious nature of the disease, which we believe is influenced to a large extent by the lifestyle in these communities.

Oral health status of institutionalized elderly Cape Coloreds from the Cape Peninsula of South Africa.

A study has been conducted to assess the oral health status and need for dental treatment among elderly Cape Coloreds resident in homes for the aged in the Cape Peninsula of South Africa. This paper describes the prevalence of diseases of the mouth with special reference to denture-induced lesions and white lesions of the oral mucosa. Dental caries was the most prevalent oral lesion (27.2%). The most common conditions of the soft tissues were leukoedema (24.4%) and leukoplakia (4.4% for the tongue; 20.4% for the remainder of the oral mucosa). Leukoedema and leukoplakia showed statistically highly significant correlations with tobacco habits. Men more commonly had a tobacco habit than women (P less than 0.002) and leukoplakia, leukoedema and depigmented lesions of the lips were significantly more common in men than in women. No significant difference could be proven statistically when the frequency of irritative fibrous hyperplasia in females was compared with that in males.

Tooth survival in institutionalized elderly Cape Coloreds from the Cape Peninsula of South Africa.

An investigation has been conducted in order to assess the oral health status and need for dental treatment among Cape Coloreds resident in homes for the aged in the Cape Peninsula of South Africa. Tooth loss was greater in females than in males (P less than 0.002) but a statistically significantly greater proportion of surviving teeth were grossly carious in men than in women (P less than 0.002). More teeth had survived in the mandible than in the maxilla (P less than 0.002) and proportionately more teeth were grossly carious in the maxilla than in the mandible (P less than 0.002). The distribution pattern of the remaining dentition according to tooth type was similar for both jaws, the canines being the most persistent teeth.

Evaluation of inbred germ-free Fischer 344 albino rats as an experimental model for oral candidiasis.

Inbred germ-free Fischer 344 albino rats were evaluated as models for experimental candidiasis in order to investigate bacterial interaction with Candida albicans. Female rats were exposed to C. albicans in their drinking water and killed at intervals from 2 to 22 days after initial contact with the contaminant. C. albicans was cultured from their mouths from day 2 but from day 12 the number of colonies decreased. From day 2 to 9 all rats showed oral histological signs of candidal infestation, but after 9 days the number declined to 3 out of 9 at 22 days. The dorsal surface of the tongue was the best histological indicator of candidal infestation. All the rats had tongue lesions from day 4 to 9, and from day 6 there was also a concomitant localized loss of filiform papillae. The number of rats with all forms of tongue involvement also decreased after 9 days with only 3 out of 9 affected at 22 days. It is concluded that Fischer 344 inbred germ-free rats can be used on a limited scale as a model for candidiasis and bacterial interaction with C. albicans, the dorsal surface of the tongue would be the best site for studying candidal experimental lesions and it is probable that better results can be achieved with complete standardization of contamination and preparation procedures.

The effect of areca nut on salivary and selected oral microorganisms.

The aim of this study was to investigate the effect on the growth of salivary and selected oral microorganisms of areca nut, aqueous extracts of the nut, its major alkaloid arecoline and the components tannic acid and catechin of its tannin fraction. The antibacterial properties of the above were tested on Streptococcus mutans, Streptococcus salivarius, Candida albicans and Fusobacterium nucleatum and, as a control, Staphylococcus aureus. This was followed by investigating its effect on salivary organisms cultured from the saliva after chewing boiled areca nut. Extracts inhibited the growth of the selected organisms in a concentration dependent manner, baked and boiled nuts being significantly more potent than raw nut. Growth of C. albicans was the least affected by the nut extracts. Tannic acid was strongly antibacterial but not catechin or arecoline. No antibacterial effect could be demonstrated on salivary organisms after chewing the nut for 5 minutes but exposure of saliva to the cud for 1 hour caused a significant depression of bacterial growth. It is concluded that the hydrolysable tannins in the tannin fraction, which include tannic acid, are responsible for the antibacterial properties of the nut and that prolonged intraoral exposure to the nut can suppress bacteria in the mouth.

A grave matter--dental findings of people buried in the 19th and 20th centuries.

The exhumed remains of 181 people, buried during the period 1848-1984 were examined. Because of the carelessness of exhumations, only 125 yielded sufficient information to compare the condition of skulls and jaws with the period in the grave, while 63 yielded information about the teeth. No correlation could be shown between the condition of the skulls and jaws and the period interred, but it was found that the better preserved remains belonged to younger people. Dental findings included the presence of healthy and decayed teeth, gold foil restorations, gold and porcelain inlays, amalgam and silicate fillings, and vulcanite and acrylic dentures. Amalgam restorations were present in people buried from 1875 (114 years ago) and vulcanite dentures from 1882 (107 years ago). The characteristics of the earliest amalgam restorations showed that they could have been placed before 1850. Findings of this study indicate that: (a) one cannot on the appearance of exhumed remains estimate the burial period, (b) dental features were well preserved and can be used for dental identification if antimortem data are available, (c) advanced dentistry could have been practised in South Africa during the last century, and (d) recovery of human skeletal remains from old cemeteries should be undertaken with care to preserve as much information as possible. A plea is made for closer co-operation between developers of old graveyard sites and scientists in order to preserve as much information as possible.

An experimental cyst model established from human unkeratinized vaginal mucosa.

Because of the scarcity of sizeable specimens of normal oral mucosa and the availability of human vaginal mucosa, which resembles the lining mucosa of the mouth, we used the latter to establish a human cyst model. Fragments of vaginal mucosa, removed during corrective procedures, were sutured around 2 mm glass balls and implanted into the flanks of nude mice. Thirty-seven specimens were implanted and 31 harvested after 3, 6, 9 and 12 weeks. At 6 weeks the wall of the implanted cyst consisted of recognizable unkeratinized vaginal mucosa but had not healed completely at the sutured edges. From 9 weeks the cyst cavities were healed and the lumens lined by unkeratinized stratified squamous vaginal epithelium. The enclosing connective tissue had retained the characteristics of the lamina propria of the vaginal mucosa and could be distinguished from mouse tissue.

A unicystic ameloblastoma mimicking a 'globulo-maxillary' cyst: a case report.

A rare case of unicystic ameloblastoma is reported, which clinically mimicked a 'globulo-maxillary' cyst. The cyst wall was lined by stratified squamous epithelium with scattered mucous cells. In one area a nodule of ameloblastic proliferation was present. The lesion was removed conservatively and there were no signs of recurrence after a 2-year follow-up period.

Recurrent unicystic ameloblastoma of the maxilla.

A previously reported unicystic ameloblastoma, showing luminal plexiform epithelial proliferation and the presence of small islands of odontogenic epithelium in the connective tissue of the cyst wall, recurred 5 years after conservative surgery. The tumour was nucleated and since the epithelial islands were confined to its fibrous capsule a conservative approach was regarded as adequate. In view of the later experience it is now proposed that where cystic ameloblastomas depict epithelial infiltration into the capsule a second excision be considered and that such surgical material be thoroughly examined for signs of epithelial infiltration. Whatever type of treatment the surgeon decides to perform, it is essential to have a long postoperative period of monitoring. Because the presence of islands of odontogenic epithelium in the cyst wall influences the surgical approach, it is recommended that pathologists carefully examine cystic ameloblastoma surgical specimens for their presence. Multiple, even serial sections are required for such examinations. The pathology report should include a description of the islands with an indication of their site in the capsule of the tumour.

Primary intraosseous carcinoma involving the anterior mandible.

A case is reported of a primary intraosseous carcinoma arising in the anterior mandible with metastasis to the submandibular lymph node in a 69 year-old Caucasian female. The patient initially presented with a burning sensation in the oral cavity in 1983, when no obvious pathological finding was noted; she returned 2 years later with a firm buccal swelling which had increased in size after the extraction of a mobile tooth. The tumour proved to be a primary intraosseous intraosseous carcinoma; extensive investigation did not reveal a primary carcinoma elsewhere.