Dietary intakes and caries experience in children in Limpopo Province, South Africa.

INTRODUCTION: The identification of a rural village with a very low incidence of dental caries among the children provided the opportunity to study the diets of children apparently not exposed to risk factors for dental caries and compare them with children who were at risk. OBJECTIVE: To compare the diet, nutritional status and dental caries experience of 10- and 15-year-olds in an urban town (Malamulele) and a rural village (Mahonisi) in the Limpopo Province, South Africa. METHODS: Dental examinations and anthropometric measurements were done according to standard procedures. Dietary intakes were assessed by four 24-hour recalls. RESULTS: Mean dft/DMFT (decayed and filled deciduous teeth/Decayed, missing and filled permanent teeth) scores were 1.21 and 0.65 for 10- and 15-year-olds in urban Malamulele compared to 0.33 and 0.02 in rural Mahonisi. The percentage caries free in Malamulele was 36% compared to 88% in Mahonisi. The children in Mahonisi were shorter and lighter than those in Malamulele. Estimated fluoride intakes were significantly lower in Malamulele than in Mahonisi (p = 0.01). Mean total added sugar (all sugar not naturally occurring in foods) intake in Malamulele was significantly higher than in Mahonisi (p < 0.05). CONCLUSION: The most significant dietary differences between the two areas were total added sugar and fluoride intakes. The lower added sugar and higher fluoride intake among the rural Mahonisi children contributed to the lower dental caries experience.

Prevalence of early childhood caries in 3- to 5-year-old children in Philadelphia district, Mpumalanga Province.

INTRODUCTION: Early Childhood Caries (ECC) can be defined as dental caries in preschool children. There is a lack of data on the prevalence of ECC at a global, national, regional and district level. Hence the severity and extent of the disease is unknown. OBJECTIVES: The purpose of the study was to establish the prevalence of ECC among 3- to 5-year-old children from the Philadelphia district in Mpumalanga. METHODS: A cross sectional study was conducted on 269 children aged between 3 and 5 years. The caries status was determined using the decayed, missing and filled teeth (dmft) index as described by WHO 1997. RESULTS The percentage caries free individuals were 74.6%, 44.2% and 46.6% and the dmft values were 0.93, 2.69 and 2.18 for 3-, 4- and 5-year-olds respectively. The mean mt and ft values for 3- and 4-year-olds was zero. Among the 5-year-olds, the mean mt and ft values was 0.01 and 0.02 respectively. CONCLUSION: For a rural community the prevalence of ECC is high. Virtually all caries in preschool children from this community is left untreated. There is a need for a properly planned preventive strategy for this community.

A comparison of results of fluoride determinations by different laboratories.

With water fluoridation imminent in South Africa, the accurate determination of the fluoride content of water is important. The aim of this study was to compare the fluoride content of water reported by 9 laboratories and the laboratory at the South African Bureau of Standards (SABS). The SABS and 9 South African laboratories were asked to determine the fluoride content of five water samples. The fluoride content of the samples was in a range that could be expected in South African waters. The laboratories were requested to disclose their methods for fluoride determination. The results reported by the laboratories were compared to the results reported by the SABS laboratory. Fluoride concentrations of 0.13, 0.22 and 0.58 mg/litre were reproduced to within 0.05 mg/litre by two, six and three laboratories respectively. At the 1.1 and 1.5 mg/litre concentration no laboratory could achieve this accuracy. Four different methods for the determination of fluoride were used. At present laboratories determining fluoride concentrations are not accurate enough to ensure that the process of water fluoridation will be safe. Laboratories will have to check their procedures to ensure better results before water fluoridation can commence.

The effect of isoniazid containing regimen on CYP2E1 during antituberculosis therapy.

Because isoniazid is a selective inducer of CYP2E1 and isoniazid-induced hepatotoxicity is believed to be due to activation of its metabolites by CYP450, this study was undertaken to determine the effect of isoniazid containing regimen on CYP2E1 in TB-patients. The activity of CYP2E1 in 11 newly diagnosed TB-patients (5 F, 6 M) was investigated before (day 0) and during (day 14) treatment for tuberculosis. CYP2E1 activity was measured using the plasma metabolic ratio (MR) of 6-hydroxy-chlorzoxazone to chlorzoxazone, while CYP2E1 quantity in the peripheral lymphocytes was measured using SDS-PAGE. By day 14 of anti-tuberculosis treatment, the activity of CYP2E1 was inhibited by 72% in 8 patients, but increased in 3 patients. The MR for the 8 patients was reduced from (Median & Range) 2.78 (1.1-21.5) on day 0, to 0.75 (0.4-1.22) on day 14, (P = 0.0006). Renal function was normal before and during the investigation. The detection of CYP2E1 by in peripheral lymphocytes was so variable that it could not be correlated with enzyme activity. Nevertheless, its detection in peripheral lymphocytes where normally is not resident indicates that CYP2E1 was induced by isoniazid. These results indicate that during treatment for tuberculosis with isoniazid containing regimen, CYP2E1 is induced but its activity is inhibited by isoniazid.

Malocclusion among 12-year-old school children in Mankweng, Limpopo Province of South Africa.

Consent was obtained from all relevant authorities to undertake an epidemiological survey to determine the occlusal status of a sample of 12-year-old Black school children in Mankweng Circuit, Limpopo Province. The examination was carried out using the Dental Aesthetic Index (DAI) criteria, under conditions prescribed by the WHO in 1987. The results were analysed using the Kotmogorov-Smirnov Test. The results of the study showed that forty seven percent (47%) of the subjects required orthodontic treatment, in the categories: definitive 20%, severe 13% and handicapping 14%. There is a proven need for orthodontic treatment among 12-year-old Black school children in Mankweng. Since there is no government hospital or clinic to provide such treatment, a centre should be established.

Caries status and treatment needs in South Africa: report of the 1999-2002 National Children's Oral Health Survey.

A third national children's oral health survey was conducted in South Africa between July 1999 and June 2002. OBJECTIVE AND METHODOLOGY: One of the objectives of the survey was to determine the prevalence and severity of dental caries and the treatment needs for dental caries in 4- to 5-, 6-, 12- and 15-year-old South African school children. The sample comprised 30876 children from the nine provinces of South Africa. RESULTS: The results of the survey show that 39.7 per cent of the 6-year-old group were caries free. This figure, 39.7 per cent, is below the goal of 50 per cent set by the Department of Health for 6-year-old children in South Africa for the year 2000. The DMFT of 1.1 for the 12-year-old group on the other hand was below the goal of 1.5 set for South Africa for the year 2000. The highest DMFT/dmft scores were recorded in the Western Cape Province and the lowest in the Limpopo Province. More than 80 per cent of caries in children go untreated while the greatest need for treatment in South African school children was for preventive services, restorations and extractions. The results for the 12-year-old-group show a reduction in dental caries severity in the permanent dentition in that the DMFT decreased from 2.5 in 1982 to 1.1 for the current survey. CONCLUSIONS: Although dental caries severity in South Africa is classified as low by WHO standards, the high levels of untreated caries in all age groups in South Africa is a cause for concern.

A fast and simple method for the determination of clavulanic acid in human plasma using derivatisation reaction kinetics.

A stopped-flow mixing technique is used to determine clavulanic acid in human plasma after plasma deproteinisation with acetonitrile and removal of the organic solvent by extraction with dichloromethane. The reaction kinetic profiles for the reaction between clavulanic acid and imidazole are determined by measuring the absorbance at 312 nm of the imidazole derivative. The reaction rates are proportional to the concentration of the clavulanic acid and by plotting reaction rates against clavulanic acid concentrations linear calibration curves could be constructed over the range 0.30-10.0 microg/ml.

The oral health status in Mahonisi: a community with very low levels of dental caries.

The oral health status and treatment needs of the community at Mahonisi were determined in order to plan a health care programme. The caries experience, occlusal status, fluorosis prevalence and prosthetic status and needs were determined according to the WHO pathfinder methodology (1987). The dmft for the 4- 5- and 6-year-old children was 0.33 and 0.67 respectively. The DMFT ranged from 0 in the 12- and 15-year-old children to 4.2 in the 65-years-and-older age group. Among the 12-, 15- and 18-year-old pupils 73% had good occlusions, 18% had slight and 9% more serious anomalies. Of the 152 subjects examined for fluorosis only 2 exhibited very mild dental fluorosis. No soft-tissue lesions were seen in the adult sample, but 10 cases were seen in the schoolchildren. No edentulous person was seen, but 4 people needed extraction of all their remaining teeth. A need for 7 partial dentures was recorded. The simplified oral hygiene index (OHI-S) ranged from 1.45 in the 4- 5-year-old children to 4.47 in the oldest group. The zero DMFT scores for the 12- and 15-year-old children are exceptional and need to be further investigated. It is recommended that the teachers in the pre-school and some of the primary school be trained to provide oral hygiene instruction to the children.

Regional urban-rural distribution of dental caries experience in Swaziland.

Understanding the regional and countrywide urban-rural distribution of dental caries in Swaziland was considered important for the formulation of a National Oral Health Policy based on the Primary Health Care Approach. A National Oral Health survey was undertaken in Swaziland at the request of the ministry of health. Part of the objective of this study was to establish the regional urban-rural distribution of dental caries in Swaziland. For the 6-18 year olds a cluster sampling technique by schools was used to get a representative sample. For the 35-44 year age group a simple random sampling technique was used in areas of employment influenced by regional and urban-rural distribution. All examinations were carried out using the WHO 1987 criteria. More than 90 per cent of the mean dmft of 6 and 12 year olds was comprised of the decayed component of the dmft/DMFT. The level of restorative care (ft/dmft, FT/DMFT) was low for all age groups. For the 6 and 12 year olds in the Lubombo region there was a significant difference (p < 0.05) in the urban-rural caries experience. When regional data for 6 and 12 year olds were pooled, the difference in urban-rural caries experience is also significant (p < 0.05). For the older age groups there was no significant difference (p > 0.05) in the regional urban-rural caries experience. This study indicates that the oral health care system in Swaziland with its limited resources, should focus its attention on the younger age groups especially in urban areas as far as dental caries treatment needs and preventive programmes are concerned.

The effect of socio-economic status on dental caries experience in 6, 12 and 15 year-old school children in Port Elizabeth and Despatch.

The socio-economic status of urbanised families throughout the world influences the caries experience of children. The higher the socio-economic status the lower the caries experience. Therefore, in surveys undertaken to determine caries experience of large communities it is necessary to take the above mentioned factor into consideration during the sampling process. It is, however, difficult and time consuming to classify individual children in terms of their socio-economic status. During a recent large scale survey in Port Elizabeth and Despatch, the whole area was divided into three socio-economic sub-sections decided on the basis of residential property values. All children attending school in a particular area was regarded as being from that particular socio-economic group. The results of the survey show that this method of classification into socio-economic groups yields similar results to those of more accurate methods of classification. The influence of the intervention by dental personnel on the caries experience, as expressed in the dmft and DMFT counts in 6-, 12- and 15-year-old children, is a matter of concern and needs further investigation.

A comparison of the effects of different concentrations of fluoride in the drinking water in different parts of Port Elizabeth and Despatch: a first report.

Since April 1993 a part of Port Elizabeth and the surrounding areas have been receiving water from the Orange river, containing on average 0.62 ppm fluoride, while the rest is still receiving water which contains < 0.1 ppm. During August 1994 a survey was done to determine whether the increased levels of fluoride in the Orange river water influenced the caries experience of school children using it. Schools in high, middle and low socio-economic areas in both areas were randomly identified and a random sample of 6-, 12- and 15-year-old children from these schools were examined for caries experience, using the 1987 WHO methodology and criteria for the diagnosis. Results of the survey show that the caries experience in the permanent dentition of 12- and 15-year-old children respectively are 14.0 per cent and 7.8 per cent less in the areas receiving Orange river water, while in the primary dentition at age 6 it is 17.2 per cent higher. This study shows that after only 16 months the use of fluoride containing water may have benefitted the permanent dentition of 12- and 15-year-old children. However the primary dentition of 6-year-old children showed a negative effect.

Water fluoridation in South Africa: will it be effective?

The National Oral Health Survey showed that differences in the prevalence and experience of dental caries occurred between racial groups and between geographical areas according to fluoride levels in the domestic water supply that varied from <0.05 ppm in the coastal areas to 0.35 ppm in the Bloemfontein area. The Orange Free State (OFS) Goldfields were not included in the survey. The fluoride content of the water supply to this community varies from 0.2 to 0.9 ppm, with a long term average of 0.54 ppm. A survey was conducted in this area to determine the effect of the raised fluoride level on the caries levels in Black and White children. The results show that caries levels in Black children in the OFS Goldfields are >50 per cent and >80 per cent lower than that found in the Bloemfontein and coastal areas respectively. In the OFS Goldfields 39 per cent of White and 16 per cent of Black 12 year old children presented with dental fluorosis on the maxillary central incisors. The results of this study seem to indicate that Black children will benefit more from water fluoridation than White children.

Project Swaziland (Part 1): development of oral health services--study methodology and summary of results.

A collaboration in oral health services research between the Kingdom of Swaziland and the Republic of South Africa is reported. The aim and methodology of the project is described and a summary of the results of the descriptive study is given. The latter included the status of dental caries, periodontal disease and malocclusion of 12 year old school children, an evaluation of a community preventive programme, an assessment of the knowledge, attitudes and behaviour of school teachers towards oral health and an analysis of the output of public oral health services. Five major strategies were recommended for the further development of oral health services in Swaziland and it is recommended that these be undertaken within the contextual realities of Southern Africa.

Project Swaziland (Part 2): dental caries experience of 12 year old school children.

This investigation was conducted to determine the prevalence of dental caries and degree of dental fluorosis in 12-year-old Swazi school children. The prevalence of dental caries was low (33.7 per cent of children experienced caries and the mean DMFT was 0.92) and corresponded with that found in a neighbouring Swazi community (KaNgwane) but differed strikingly from the results of the baseline study by Klausen and Fanoe (1983). The need for curative dental care was mainly for one surface restorations. A need for selective school preventive programmes was identified.

Double-blind randomized cross-over trial of nocturnal elixir theophylline supplementation of a twice-daily sustained-release theophylline tablet formulation in asthmatic patients.

Sixteen asthmatic patients with normal diurnal activity between 05:00 and 23:00 h participated in this randomized, multiple-dose, double-blind, placebo-controlled, crossover study of the pharmacokinetics and efficacy of evening supplementation of a 12-hourly sustained-release theophylline (SRT) regimen with a nonsustained-release theophylline (NSRT) formulation. The treatments were Nuelin SA (SRT) every 12 h plus, in the evening, either placebo or an additional dose of Nuelin liquid (NSRT), determined to raise the early morning (0300) plasma theophylline concentration (PTC) to 18 micrograms/ml by using the dose-concentration prediction equation established in a study conducted on healthy volunteers and reported in this journal. The 11-day trial included two 24-h inpatient periods during which PTCs and lung functions (PEF, FEV1, FEF25-75, and FVC) were determined every 2 h. The value of the prediction equation was confirmed when the early morning PTC, after evening supplementation with Nuelin Liquid, was raised nearly to the targeted 18 micrograms/ml. The nocturnal peak-to-trough fluctuation in PTC was larger during additional treatment with Nuelin liquid, but the nocturnal peak-to-trough fluctuation in lung function parameters decreased. Overall, airflow during the early morning hours (0100-0500) significantly improved during this chronotherapeutically optimized treatment of adding an NSRT product to the evening dose of a 12-hourly SRT regimen.

Theophylline dose-concentration relationship of a 12-hourly Nuelin SA regimen supplemented with nocturnal nuelin liquid in healthy volunteers.

Twelve healthy male volunteers who were diurnally active between 05:00 and 23:00 took part in a randomized, multiple-dose, double-blind, four-way, crossover study to determine the relationship between the dose of a nonsustained-release theophylline (NSRT) formulation added to the evening administration of a 12-hourly sustained-release theophylline (SRT) regimen and the elevation of the early morning (between 02:00 and 05:00) steady-state plasma theophylline concentration. The four treatments were 250 mg Nuelin SA (sustained-release theophylline) every 12 h plus either placebo or Nuelin liquid (non-sustained-release theophylline) equivalent to 100 mg, 200 mg, or 300 mg of theophylline. Without evening supplementation (placebo), the early morning plasma theophylline concentrations were 13% lower than the average 24-h concentration, but with evening supplementation the early morning plasma theophylline concentration could be raised up to and above the average 24-h concentration. A prediction equation for the early morning plasma theophylline concentration as a function of the additional evening dose of Nuelin liquid, and of the steady-state evening trough plasma theophylline concentration without evening supplementation, was established. This prediction equation can be used to determine the additional evening dose of Nuelin liquid (administered at 19:00) needed to reduce early morning bronchoconstriction in asthmatic patients who are on a 12-hourly Nuelin SA (drug administered at 07:00 and 19:00) regimen.