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Biomedical subjects

R D Holt

Publications and source records attributed to R D Holt.

At least 37 records · Page 2Linked to original sources
PubMed2001

Clinical and photographic assessment of erosion in 2-5-year-old children in Saudi Arabia.

OBJECTIVE: To compare findings from photographs of incisor teeth in pre-school children in Jeddah, Saudi Arabia to those on clinical examination for dental erosion. BASIC RESEARCH DESIGN: Cross sectional study of 2-5-year-old Saudi Arabian children using two methods of examination. MEASUREMENT: of erosion was carried out clinically using a scoring system and criteria based on those used in the United Kingdom national surveys. Photographs of labial and palatal surfaces of maxillary primary incisors were taken for each child and scored in the same way. SETTING: Kindergarten schools in Jeddah, Saudi Arabia. PARTICIPANTS: 987 children from 17 randomly selected schools in Jeddah, Saudi Arabia. RESULTS: Readable photographs were available for 727 children. Two hundred and twenty (30%) had photographic evidence of tooth tissue loss. Prevalence estimates derived from clinical examination were higher than those for photographs (36% compared to 30%). Agreement was seen between the two methods for 93% of the surfaces included. CONCLUSIONS: Photographs have been employed in research in dentistry as well as for documentation and illustration. In epidemiology they have proved to be valuable in measuring enamel defects but have not been used for other conditions. Photographs have potential in measuring erosion, but may benefit from refinement.

Chi-Square Distribution↗
PubMed2000

Prevalence of caries and developmental defects of enamel in 9-10 year old children living in areas in Brazil with differing water fluoride histories.

AIMS: To assess the prevalences of caries, of developmental defects of enamel and their interrelationship in Brazilian 9-10-year-olds from areas of contrasting fluoridation histories. METHODS: Systematic random sampling procedures were used to select children from an area where water had been fluoridated in 1963 and from a second area where water had been fluoridated since 1998. Clinical examinations for caries were carried out using the DMFT index and WHO diagnostic criteria. Developmental defects of enamel on upper incisors were diagnosed using the DDE index. RESULTS: A difference of 40% in DMFT was observed, with a lower prevalence of disease in the area fluoridated since 1963. Diffuse opacities affected 14.3% of the children from the area fluoridated since 1963 compared with only 2.4% in the area fluoridated in 1998. Children living in the area fluoridated in 1963 who had diffuse defects had twice the chance of being free from caries compared with those living in the same area who had no defects or who had only demarcated or hypoplastic defects. CONCLUSIONS: This study confirms previous ones in showing the benefits of water fluoridation. Diffuse opacities of upper incisors affected relatively few subjects in either of the two areas.

Brazil↗
PubMed2000

Caries and its association with infant feeding and oral health-related behaviours in 3-4-year-old Brazilian children.

OBJECTIVES: To investigate the relationships between socio-demographic factors, infant feeding habits, oral hygiene and the prevalence and patterns of caries in Brazilian 3-4-year-olds. METHODS: Systematic random sampling was used to select children enrolled in municipal nurseries in Araraquara, Brazil, in 1998. Clinical examinations were carried out by one examiner using dmft and dmfs indices and WHO criteria. Questionnaires for information related to the socio-demographic background, oral hygiene and dietary history of the children were completed by their mothers. RESULTS: Caries was seen in 46% of the children; 17% of them had the more extensive pattern involving molars and incisors. Social class, mother's education, and age at which breast-feeding terminated showed statistically significant associations with caries. Feeding bottles with added sugars were still being given to 80% of the children. When the significant variables were taken into account only age at which breast-feeding terminated showed a significant relationship to the pattern of disease. Children who were never breast-fed or were breast-fed beyond the age of 24 months had a higher prevalence of the more extensive pattern of caries. CONCLUSIONS: The association between the length of time a mother breast-feeds and extensive caries should be a consideration in any local infant feeding policies or health promotion strategies. The duration for appropriate breast- or bottle-feeding should be emphasised.

Bottle Feeding↗
PubMed2000

A retrospective study of unerupted maxillary incisors associated with supernumerary teeth.

We retrospectively reviewed the clinical records and radiographs of 100 patients who had had supernumerary teeth removed. Their mean (SD) age was 9 years 3 months (2). The 100 patients had a total of 127 unerupted maxillary incisors associated with supernumerary teeth. The supernumerary tooth was removed without exposure of the permanent tooth more often among the 79 younger children (aged 10 years or less) (SND=3.52, P<0.01), and when the incisors were less mature (Cvek classification 1, 2, and 3) (SND=5.27, P<0.01). Of these incisors with immature roots that were treated conservatively, 60 (72%) erupted and 24 (28%) required further operation. Of the mature incisors treated conservatively, 10 (63%) required further operation. In this study, almost three-quarters of immature incisors erupted spontaneously after removal of the associated supernumerary teeth. Over half of the mature teeth required further operation. Mature teeth should be exposed with or without bonding at the time of removal of the supernumerary teeth.

Adolescent↗
PubMed2000

The prevalence of caries and of tooth tissue loss in a group of children living in a social welfare institute in Jeddah, Saudi Arabia.

AIM: To measure the prevalence of caries, rampant caries and erosion in a group of 4-5-year-old children living in an institution in the city of Jeddah in the West Province of Saudi Arabia. DESIGN: Descriptive, cross sectional. SAMPLE AND METHODS: A total of 80 children (51 boys, 29 girls) living in the Institute were examined visually for caries using BASCD criteria. Erosion of palatal and buccal surfaces of maxillary incisors was scored: 0 (no erosion), 1 (erosion into enamel), 2 (erosion into dentine) and 3 (erosion involving the pulp). RESULTS: Twenty-four of the Children (30 per cent) had caries and two had rampant caries. Mean dmft was 0.95 (+/- 2.03) and mean dmfs was 3.2 (+/- 6.51). These values are lower than other estimates for children of this age in Saudi Arabia. Ten children (12.5 per cent) had erosion affecting buccal or palatal surfaces of their maxillary incisor teeth. In seven, erosion was confined to enamel but in three it extended into dentine. CONCLUSION: The lower caries levels seen in this group of children may be at least partly attributable to the effectiveness of strict dietary control and regular oral hygiene measures.

Child, Preschool↗
PubMed2000

Oral health status and access to care in a rural area of India.

A study was carried out in two villages in a rural area of Andhra Pradesh, India, 150 kilometres south of the state capital, Hyderabad. Ninety-eight women and sixty-two men, age range 15-70 years, were interviewed and examined. Information gathered included socio-economic data, distance travelled outside the village and previous access to health care. Data were recorded on periodontal status using CPITN and full periodontal charting. Comparisons were made between male and female subjects for travel outwith the village, attendance at medical and dental health facilities, tooth cleaning methods and materials and prevalence of periodontal disease. There was a high prevalence of chronic inflammatory periodontal disease in this population, and most of this was untreated. In view of the difficulties in access to health care, it would be prudent to offer good preventive oral health care within the rural community.

Adolescent↗
PubMed1999

Provision of dental general anaesthesia for extractions in child patients at two centres.

AIM: To two contrasting centres, to describe the provision of dental general anaesthesia (DGA) for simple non-surgical extractions in terms of the type of treatment provided, including the number of primary and permanent teeth extracted, and the characteristics of child patients attending in terms of their age group and gender. DESIGN: Retrospective analysis of hospital records. METHOD: Data were drawn from records of services over a 12-month period in 1996/97 at: a) a London dental hospital (Centre 1), and b) in the community dental services in Rochdale, Lancashire (Centre 2). Information was collated and analysed using the SPSS statistical software package. RESULTS: The majority of patients at both centres were aged less than 9 years. Almost one third (31%) of those seen at Centre 1 were below 5 years of age, but fewer of this age group were treated at Centre 2. Children aged 9 years or less had an average of 5.4 (SD = 3.0) primary teeth extracted at Centre 1 and 3.0 (SD = 2.0) at Centre 2. For permanent teeth, an average of 3.2 (SD = 1.2) and 2.7 (SD = 1.4) were extracted at Centres 1 and 2 respectively. CONCLUSIONS: Both services were used primarily for the extraction of primary teeth although the services differed in the ages of patients who used them and in the numbers of teeth extracted. Numbers of patients attending the service at Centre 1 had declined over time but numbers of teeth extracted per child had increased.

Adolescent↗
PubMed1999

The effects of density dependence and immigration on local adaptation and niche evolution in a black-hole sink environment.

We examine the effects of density dependence and immigration on local adaptation in a "black-hole sink" habitat, i.e., a habitat in which isolated populations of a species would tend to extinction but where a population is demographically maintained by recurrent one-way migration from a separate source habitat in which the species persists. Using a diploid, one-locus model of a discrete-generation sink population maintained by immigration from a fixed source population, we show that a locally favored allele will spread when rare in the sink if the absolute fitness (or, in some cases, the geometric-mean absolute fitness) of heterozygotes with the favored allele is above one in the sink habitat. With density dependence, the criterion for spread can depend on the rate of immigration, because immigration affects local densities and, hence, absolute fitness. Given the successful establishment of a locally favored allele, it will be maintained by a migration-selection balance and the resulting polymorphic population will be sustained deterministically with either stable or unstable dynamics. The densities of stable polymorphic populations tend to exceed densities that would be maintained in the absence of the favored allele. With strong density regulation, spread of the favored allele may destabilize population dynamics. Our analyses show that polymorphic populations which form subsequent to the establishment of favorable alleles have the capacity to persist deterministically without immigration. Finally, we examined the probabilistic rate at which new favored alleles arise and become established in a sink population. Our results suggest that favored alleles are established most readily at intermediate levels of immigration.

Animals↗
PubMed1998

Comparison of two indices of caries patterns in 3-6 year old Brazilian children from areas with different fluoridation histories.

The purpose of this study was to define the pattern of caries in 3-6 year old children from two districts in Araraquara, SP, Brazil, fluoridated for more than 10 years and from a much more recently fluoridated one in the same city, using two different indices. The study included 1,066 children (903 from the two first districts and 163 from the third). Patterns of disease were described in terms of prevalence and dmft in molars, incisors (and/or canines) individually and together. Pattern was also described according to the 'caries analysis system'. In both areas the majority of 3-4 year olds had disease confined to primary molars. In the areas fluoridated for more than 10 years, the highest proportion of 5-6 year olds with caries also had the disease confined to primary molars (36 per cent) but in the more recently fluoridated area, similar proportions of children had caries in primary molars alone as had caries in both primary molars and incisors (40 per cent and 44 per cent, respectively). Results according to the 'caries analysis system' showed that in both areas the prevalence of fissure caries and posterior bucco-lingual surface pattern in 5-6 year olds were twice as great as those observed in 3-4 year olds. Differences between the areas were obvious whichever method was used to define pattern, confirming the benefits of water fluoridation. The simpler method of grouping tooth type affected showed the differences as effectively as the more complex 'caries analysis system'.

Age Factors↗
PubMed1998

Prevalence and severity of caries in 3-12-year-old children from three districts with different fluoridation histories in Araraquara, SP, Brazil.

OBJECTIVE: To determine the prevalence and severity of caries in 3-12-year-old children in three districts of the city of Araraquara. DESIGN: An epidemiological survey was carried out by trained and calibrated examiners in 1995 and 1996, using the WHO diagnostic criteria. SETTING: Two districts, Araraquara and Vila Xavier had been fluoridated since 1963 and one, Gavião Peixoto, since 1994. SUBJECTS: The study included 1,191 children from Araraquara, 653 from Vila Xavier and 652 from Gavião Peixoto. OUTCOME MEASURES: Prevalence of caries, dmft, dmfs, DMFT and DMFS indices. RESULTS: Results showed moderate caries experience in all three districts. Differences between districts in relation to fluoridation history were particularly obvious in primary teeth. In 3-4-year-old children, one third of those in Araraquara and Vila Xavier had some caries experience compared to 58% in Gavião Peixoto. In permanent teeth, 20% or less of the mean DMFT was made up of untreated decay in Araraquara and Vila Xavier whereas in Gaviao Peixoto it made up between 50 and 57% of values in 7-12-year-old children. CONCLUSIONS: The prevalence and severity of caries was lower in dentitions of children from the districts fluoridated since 1963. Improvements are likely in the future in Gavião Peixoto as the benefit of fluoridation continues but additional means of promoting oral health are needed in all three districts.

Age Factors↗
PubMed1997

The influence of audit on the diagnosis of occlusal caries.

Audit is widely used to improve the quality of care in both medicine and dentistry but has not always been subject to systematic evaluation. The aim of this study was to assess the effect of an audit exercise on the diagnosis of occlusal caries. Using combined visual and radiographic methods. 11 dentists assessed 60 extracted molars for occlusal caries on two occasions. An audit exercise, in the form of a meeting, was carried out in the intervening period. Inter- and intra-examiner reproducibility were estimated for each of the two examinations. Validation was through a gold standard set up by sectioning the teeth. Wide diagnostic disparity was seen at both examinations, all inter- and intra-examiner kappa values were below 0.73. Intra-examiner kappa values increased significantly on the second occasion. Mean sensitivity and specificity were 0.65 and 0.74, respectively, at the first examination and 0.65 and 0.72 at the second. No changes were seen that could be attributed directly to the audit exercise but practising the diagnostic test appeared to be beneficial to intra-examiner reproducibility of diagnosis.

Child↗
PubMed1997

Developments in fluoride toothpastes--an overview.

OBJECTIVE: This paper reviews current issues in the development of fluoride toothpastes as a public health measure. DESIGN: The issues examined included low concentration formulations, delivery systems, dispensing instructions and labelling, oral clearance. effect on root caries, additional therapeutic agents and marketing and manufacturing issues. RESULTS: Lower fluoride formulations may carry a lower risk of fluorosis but this must be balanced against a higher risk of caries. Risk factors for fluorosis include inappropriate fluoride supplements but the age at which toothbrushing began, frequency of brushing and residence in an optimum fluoride area have also been implicated. CONCLUSIONS: The dental profession should: clarify the most appropriate fluoride concentration in toothpastes used for children; ensure that other sources of fluoride do not increase the risk of dental fluorosis: investigate the effectiveness of fluoride toothpaste in inhibiting root surface caries in adults. Manufacturers should: continue to improve the performance of fluoride toothpaste; ensure that all pastes maximise fluoride bioavailability; develop active agents to help reduce oral disease; label products clearly with ppm F; review the delivery systems so as to reduce the risk of dental fluorosis.

Adult↗
PubMed1996

The national diet and nutrition survey of 1.5 to 4.5 year old children: summary of the findings of the dental survey.

A dental health survey was included as part of a large scale study of nutrition in preschool children. The survey was carried out in 1992/93 and was published in spring 1995. Information on dental health status and on dietary intake was gathered from a total of 1658 children from 100 geographical sectors in the United Kingdom. This article summarises the main findings and highlights some of the most important findings regarding dental health and its relationship to dietary factors. Seventeen per cent of children had some caries experience and in 83% of cases this was untreated. Dental decay was most strongly related to social background. The factors most strongly related to caries prevalence were: receipt of income benefits, in the 1.5-2.5-year-old children; the educational status of the mother in the 2.5-3.5-year-old children and social class of the head of household in the 3.5-4.5-year-old children. Consumption of sugary drinks at bedtime, children being left to brush their teeth themselves, household expenditure on confectionery and geographical region were also strongly associated with caries prevalence.

Beverages↗
PubMed1996

The weaning diet and dental health.

Weaning practice can have a major influence on both immediate and future dental health and good dietary practices from birth have the potential to secure a healthy dentition for life. In a recently published report it is recommended that infants (an infant may be defined as a child who has not yet reached the age of one year) be weaned on foods and drinks free as far as possible of non-milk extrinsic (NME) sugars. At the same time, there has also been an increasing development of low-sugar and sugar-free products for infants. There has also been growing concern that infant drinks with low pH may cause enamel erosion in primary teeth, a phenomenon that is perhaps more widespread than has been recognised in the past. The aim of the weaning diet is to achieve a diet which fulfills nutritional requirements for the growing child and which contains a wide variety of foods and drinks. It is suggested that items high in NME sugars are not a necessary part of the diet, should be regarded as 'occasional', and not given every day. Drinks other than milk or water should constitute a minority of total drinks and be given only at main mealtimes; they should not be given in bottles or at bedtime.

Beverages↗
PubMed1996

Fissure sealants: a 4-year clinical trial comparing an experimental glass polyalkenoate cement with a bis glycidyl methacrylate resin used as fissure sealants.

The 4-year results of a fissure sealant trial are reported. Glass polyalkenoate and bis GMA sealant were applied to 590 first permanent molar teeth using a half mouth study design in a group of 228 6-8-year-old children. Similar cariostasis was observed for the two materials at the end of 4 years despite marked differences in retention. Polyalkenoate cements probably should be regarded as 'fluoride depot' materials rather than fissure sealants when used in this context.

Bisphenol A-Glycidyl Methacrylate↗