Biomedical subjects

Ralph M Duckworth

Publications and source records attributed to Ralph M Duckworth.

4 recordsLinked to original sources

PubMed2005

Evidence for putting the calculus: caries inverse relationship to work.

OBJECTIVES: To report previously unpublished data from three different types of clinical study to show the strength of the evidence purporting to demonstrate the existence of an inverse relationship between subjects' calculus and caries experience. METHODS: Data have been analysed from: a 3-year caries clinical trial of six toothpastes conducted in Lanarkshire, Scotland that involved 3000 children, Study 1; a caries epidemiological study in the Isle of Lewis that involved 228 children, Study 2; a calculus formation study carried out at Port Sunlight using a wide age range of adults, Study 3. RESULTS: Baseline data taken from Study 1 show that caries prevalence is highly significantly lower in calculus-prone than in calculus-free subjects (P < 0.0001). The inverse relationship is also demonstrated by the 3-year caries increment data for subjects who had used non-zinc toothpastes. Results from Study 2 show that a similar association arose for 8-year olds over a 6-year period, based on their erupting teeth alone. Finally, data from Study 3 show that whilst the extent of caries and calculus experience are both positively linked to age, within specific age groups the relationship between the two dental conditions on an individual subject basis is clearly of an inverse nature. CONCLUSIONS: The present work confirms that calculus status has a direct bearing on both current and future caries experience. Baseline calculus status could be, and has subsequently been demonstrated to be, a useful stratifying factor for caries clinical trials.

Adolescent↗

PubMed2004

Development of a standardized method for comparing fluoride ingested from toothpaste by 1.5-3.5-year-old children in seven European countries. Part 1: Field work.

OBJECTIVES: To develop a standardized method for measuring the variables affecting fluoride ingestion from toothpaste in young children between the ages of 1.5 and 3.5 years, and to use the method at seven European sites. METHODS: Random samples of children were invited to take part in the study. Parents who gave consent were visited at home. The children brushed their teeth using the toothpaste brand and toothbrush type currently in use. Variables measured were: type of toothpaste used, fluoride concentration of toothpaste used, weight of toothpaste used, frequency of brushing and body weight of the child. RESULTS: It was not possible to follow the agreed protocol in all seven countries and in three countries appropriate alternative methods were employed. There was considerable variation between countries in the variables investigated. Use of children's toothpaste ranged from 69% in Ireland to 98% in Portugal. In the Netherlands up to 60% of the children were using toothpaste containing <400 ppm F and in Finland up to 27% of children were using toothpaste containing >1200 ppm F. Over half of the children used <0.25 g of toothpaste per brushing and the majority of children brushed once or twice per day. CONCLUSION: Although adherence to the agreed protocol was not possible at all study sites there was a clear picture of considerable variation in the oral hygiene practices of young children throughout Europe.

Analysis of Variance↗

PubMed2004

Development of a standardized method for comparing fluoride ingested from toothpaste by 1.5-3.5-year-old children in seven European countries. Part 2: Ingestion results.

OBJECTIVES: To develop a standardized method for measuring the variables affecting fluoride ingestion from toothpaste in young children between the ages of 1.5 and 3.5 years, and to use the method at seven European sites. METHODS: Random samples of children were invited to take part in the study. Parents who gave consent were visited at home. The children brushed their teeth using the toothpaste brand and toothbrush type currently in use. The difference between the fluoride dispensed onto the toothbrush and the fluoride recovered after accounting for losses was deemed to be the fluoride ingested. Details of other oral health-care habits were collected by questionnaire. For each child, the fluoride concentration of the toothpaste used was measured in the laboratory, from which an estimate of total daily fluoride ingestion was made. RESULTS: There was considerable variation between countries in the types of toothpaste used and in the amounts of toothpaste applied and ingested. The amount of fluoride ingested ranged from 0.01 to 0.04 mg fluoride per kg of body weight per day. CONCLUSION: The amount of fluoride ingested that is likely to be a risk factor for the development of dental fluorosis during tooth formation is equivocal and was found to vary widely between European countries. There appears to be a need for clearer health messages regarding the use of fluoridated toothpaste by young children.

Analysis of Variance↗

PubMed2004

Fluoride ingestion from toothpaste: fluoride recovered from the toothbrush, the expectorate and the after-brush rinses.

OBJECTIVES: The aim of this study was to determine the effects of rinsing and spitting on fluoride ingestion from toothpaste during normal oral-hygiene procedures of younger children, and hence to make recommendations on rinsing during toothbrushing. METHODS: The brushing habits of 166 Dutch and 185 Irish children between 1.5 and 3.5 years were observed during home visits. The weight of the toothpaste tube was determined before and after use. After brushing, the toothbrush and any associated expectorate and rinses, combined with any toothpaste spilled during the brushing procedures, were collected. The amounts of fluoride retained on the toothbrush and in the associated expectorate and rinses were measured. RESULTS: Over 90% of the Dutch children used a special toddlers' toothpaste with < or =500 ppm F. Eleven per cent of the younger (<2.5 years) Dutch children and 22% of the older children rinsed after brushing. Of the Irish children approximately 52% used a children's toothpaste containing around 500 ppm F. Of the younger Irish children 31% spat without rinsing, while another 31% rinsed during or after brushing. For the older Irish children, these percentages were 14 and 70%, respectively. On average, 22% of the fluoride dispensed on the toothbrush was retained on the brush after brushing irrespective of the rinsing and spitting behaviour of the children. The maximum ingestible amount of fluoride from toothpaste assuming no rinsing or spitting was calculated. CONCLUSIONS: Fluoride ingestion from toothpaste is significantly reduced by rinsing and/or spitting during toothbrushing. Recommendations that younger children use small amounts of toothpaste (< 0.5 g) and that children using toothpaste with > or = 1000 ppm F rinse their mouths after brushing continue to be valid.

Cariostatic Agents↗