Biomedical subjects

D Locker

Publications and source records attributed to D Locker.

At least 127 records · Page 7Linked to original sources

PubMed1993

Detection of minor adducts in cisplatin-modified DNA by transcription footprinting.

Two DNA restriction fragments containing either a d(GC)5 or a d(TTGCTTGATTAGTTGTGTT) insert were subjected to reaction with cis-diamminedichloroplatinum(II) and were then used as templates for RNA synthesis by T7 RNA polymerase. Within the d(GC)5 insert, interstrand cross-links are preferentially formed. Within the second insert, the reactivity order of the potential binding sites is d(ApG) > d(GpC/GpC) = d(GpA) > d(GpTpG). In the presence of cyanide ions, the adducts are much less stable at the d(GpA) sites than at the d(GpCpG) sites, in double-stranded DNA.

Base Sequence↗

PubMed1993

Effects of non-response on estimates derived from an oral health survey of older adults.

A major source of bias in health surveys is non-response on the part of those selected to take part in a study. In a survey of the oral health of older adults in Ontario, Canada, we used an initial telephone survey based on random digit dialing with a personal interview and clinical examination follow-up. The telephone survey was completed by 3033 individuals (78.0%) of those sampled. The follow-up was completed by only 907 (30.0%) of these subjects. Nevertheless, there were no major differences in the characteristics of those completing the telephone survey and those subsequently participating in the follow-up. Non-response bias analysis indicated that differences between crude and adjusted estimates of the prevalence of oral conditions were small and the effect of non-response on estimates of the relationship between socioeconomic status and oral health in this population were also small. These results indicate that response rates lower than those conventionally regarded as acceptable do not necessarily compromise the results of epidemiological studies.

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PubMed1993

Subjective reports of oral dryness in an older adult population.

In this study of an older adult population almost one-fifth reported oral dryness. It was the most common of 22 oral symptoms and complaints. In a logistic regression analysis of predictors of oral dryness three variables had significant independent effects: income, taking prescribed medications and experiencing a stressful life change within the previous 6 months. Subjects with oral dryness had more decayed crown surfaces than those without but there was no association with decayed root surfaces. Nor were there any significant associations between reports of oral dryness and a number of indicators of periodontal health. Those with dryness were more likely to report other oral symptoms such as unpleasant taste, a burning sensation in the tongue and other parts of the mouth and pain from dentures. They were also more likely to report problems chewing food, problems with eating and communication and were more likely to be dissatisfied with their oral health. Given its prevalence and effects, oral dryness constitutes an important health issue among older adults.

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PubMed1993

Periodontal attachment loss in independently living older adults in Ontario, Canada.

This paper describes the periodontal disease experience of a community-dwelling population aged 50 years and older, living in four communities in Ontario, Canada. The periodontal status of this population was assessed using attachment loss and the extent and severity index. Attachment loss was measured at two sites on each tooth using a pressure-sensitive periodontal probe. Complete periodontal data were obtained on 624 subjects. The mean number of sites per subject was 37.9. In line with recent US studies, the diagnostic threshold for a diseased or previously diseased site was set at 2 mm of loss. The overall mean attachment loss was 2.95 mm, with 19.7 percent of subjects having an overall mean attachment loss of 4.00 mm or more. The proportion of sites examined with loss of attachment of 2 mm or more was 77 percent. The severity of disease, defined as the average distance between the base of the sulcus or pocket and a point 1.00 mm apical to the cemento-enamel junction in sites with loss of 2 mm or more was 2.44 mm. These data indicate that the extent and severity of disease in this population were greater than that reported by some recent studies in the US. Taken together, the results of these studies suggest that there is some variation in the periodontal disease experience of population subgroups across North America.

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PubMed1993

Coronal and root decay experience in older adults in Ontario, Canada.

This paper describes the coronal and root caries experience of subjects aged 50 years and older living in four communities in Ontario, Canada. The data were obtained as part of a comprehensive epidemiologic study of the oral health and treatment needs of this population. Caries experience was defined as the number of decayed and filled coronal and root surfaces per subject. Of 907 subjects interviewed and clinically examined, 78.3 percent were dentate and retained a mean of 18.9 teeth. The mean number of coronal decayed and filled surfaces was 23.9; 95.6 percent of subjects had at least one coronal DFS. The mean number of decayed and filled root surfaces was 3.6; 70.9 percent had at least one root DFS. The percent D/DFS was 3.5 for coronal and 20.0 for root caries. In linear regression analysis the number of teeth, making regular preventive visits, being born in Canada, and educational status emerged as predictors of coronal DFS. Predictors of root DFS were the number of surfaces with recession, the number of coronal DFS, the number of teeth, age, sex, and smoking status. These variables accounted for 42 percent and 35 percent of the variance in the number of coronal and root DFS, respectively.

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PubMed1993

Risk indicators and risk markers for periodontal disease experience in older adults living independently in Ontario, Canada.

This study examined risk indicators and risk markers for periodontal disease experience in 624 adults aged 50 years and over living independently in four communities in Ontario, Canada. The data were collected as part of the baseline phase of a longitudinal study of the oral health and treatment needs of this population. Periodontal disease experience was assessed in terms of attachment loss, measured at two sites on each remaining tooth. Bivariate and multivariate analyses were used to examine the relationship between a number of sociodemographic, general health, psychosocial, and oral health variables and three indicators of periodontal disease experience. These were: mean attachment loss, the proportion of sites examined with loss of 2 mm or more, and the probability of the subjects having severe disease, arbitrarily defined as a mean attachment loss in the upper 20th percentile of the distribution. Mean attachment loss was 2.95 mm (SD = 1.41 mm), and 76.6% of sites examined had loss of 2 mm or more. In bivariate analyses, the most consistent predictors of periodontal disease experience were: age, education, income, smoking, dental visiting, the number of remaining teeth, the number of decayed coronal surfaces, and the number of decayed root surfaces. In multivariate analyses, age, education, current smoking status, and the number of teeth had the most consistent independent effects. These data confirm the results of recent US studies indicating that periodontal disease experience is influenced by social and behavioral factors.

Age Factors↗

PubMed1993

Factors affecting gay and bisexual men's decisions and intentions to seek HIV testing.

OBJECTIVES: This paper describes the relationships of sociodemographic, attitudinal, and behavioral variables to (1) decision to be tested, (2) expressed intention to be tested, and (3) reasons for not being tested for the human immunodeficiency virus (HIV) antibody. METHODS: A sample of 1295 men completed an anonymous questionnaire in gay-identified venues. Factor analysis was used to group reasons for not being tested and logistic and multiple linear regression were used to model the dependent variables. RESULTS: Fifty-three percent of the respondents had been tested, of whom 26% tested positive. Metropolitan residence and anal intercourse most strongly correlated with previous test-seeking. Previous test experience correlated most strongly with intention to be tested. Reasons for not being tested fell into three groups: (1) desire for anonymity, (2) self-perceived health, and (3) no benefit and denial. The odds were lower for gay men than bisexuals and men who did not participate in anal intercourse to express a desire for anonymity. CONCLUSIONS: Public health agencies should be prepared to individualize testing policies and education to deal with specific concerns and fears. Improving access to the test by removing some of the current psychological and physical barriers will enhance its medical and public health value.

AIDS Serodiagnosis↗

PubMed1993

Oral health and the quality of life among older adults: the oral health impact profile.

A number of studies are beginning to show that oral disorders can have a significant impact on the functional, social and psychological well-being of older adults. The Oral Health Impact Profile (OHIP) was developed to collect information on the nature and extent of this impact, and to facilitate the use of such data in oral health surveys, the evaluation of dental procedures and the clinical evaluation of patients. This paper describes OHIP and the results of two studies undertaken in Ontario to assess its measurement properties and to provide preliminary data on the way in which oral conditions compromise the quality of life of older adults. The measure proved to be reliable and valid, while data collected using this measure indicated that oral conditions have a negative impact on the daily lives of substantial proportions of older people. This impact was particularly marked among both edentulous and dentulous individuals who did not make regular visits for dental care.

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PubMed1993

Measuring social inequality in dental health services research: individual, household and area-based measures.

The literature on inequalities in health is extensive and provides convincing evidence that lower socio-economic groups have poorer general and dental health than higher socio-economic groups. In this literature, socio-economic status has been measured in terms of occupation, income or education. These conventional measures have a number of methodological and theoretical weaknesses which limit their ability to fully describe and explain differences in health between population sub-groups. In this paper, these measures are reviewed and alternatives, in the form of area-based indicators, are considered. The evidence suggests that measures of the socio-economic characteristics of neighbourhoods are better predictors of the health status of population subgroups than measures of the socio-economic characteristics of individuals or households. Moreover, they add additional explanatory power to models of health inequalities. Area-based measures can be readily applied to survey data or information derived from health records or routinely collected sources. Since they identify where deprived groups with relatively poor health live, they may prove useful in terms of the planning and targeting of health services. These alternative indicators should be explored in the context of dentistry to determine their ability to predict differences in dental health and risk factors for dental disorders among different segments of the population.

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PubMed1992

Genomic organization and nucleotide sequence of a long mosaic repetitive DNA in the mouse genome.

A long mosaic repetitive sequence (LMRS) was isolated from a mouse liver genome library using a mouse repetitive DNA as a probe. LMRS exhibits the following features: (1) it is almost 15 kb in length; (2) it is partly organized in tandem array and frequently interrupted by other repeated sequences; and (3) it is located predominantly on the A3 band of the mouse X Chromosome (Chr). One fragment of LMRS (B6) shows restriction fragment length polymorphism (RFLP) between different mouse strains, and is thus potentially useful for mapping studies. The nucleotide sequence confirms a mosaic organization of LMRS which includes three repeats in the 5' part, showing similarity with the 5' end of L1Md-A2, and seven long A + T rich segments in the central part of the element. Our findings suggest that this sequence may have arisen from the duplication of an ancestral motif and has expanded by successive waves of amplification and invasion by foreign sequences.

Animals↗

PubMed1992

Dental visit satisfaction in a group of adults aged 50 years and over.

Studies have found that utilization of dental services is generally less common than utilization of medical services, particularly by older persons. Because satisfied dental patients were found to be greater users of the service than nonsatisfied patients, it was decided to investigate the correlates of dental visit satisfaction in older subjects. Predictions that satisfaction would be positively related to regular use of dental services and negatively related to dental anxiety were confirmed. The results also suggested that older dental patients have different expectations of their dentists than younger ones.

Age Factors↗

PubMed1992

Clinical correlates of dental anxiety among older adults.

Most studies of the relationship between dental anxiety and oral health status have used subjective rather than clinical indicators of oral health. In this paper we examine differences between older adults who are and are not dentally anxious using a broad range of clinical measures. The data show that dentally anxious individuals were more likely to be edentulous, and among the dentate, had more missing and fewer filled teeth. As a result, dentally anxious dentate subjects were more likely to need prosthodontic treatment. They were also more likely to need immediate treatment for the relief of pain and infection and periodontal care. There was evidence to suggest differences in patterns of dental treatment between those who were and were not dentally anxious and some evidence consistent with the hypothesis that aging influences the relationship between dental anxiety and oral health status.

Aging↗

PubMed1992

Oral self-care behaviours in older dentate adults.

Defining oral self-care as activities undertaken by individuals to maintain or promote dental health, this paper examines the distribution of oral self-care behaviours in a sample of dentate adults, age 50 and over, living in Ontario, Canada (n = 713). Results are presented separately for two older cohorts, respondents ages 50-64 and those 65 and older, and for females and males. Six oral self-care behaviours were examined: toothbrushing, flossing, use of an interdental device, extra fluoride use, frequency of between meal snacks and ingestion of cariogenic foods. High rates of self-care occurred only for toothbrushing. Age groups differed significantly for use of interdental devices, consumption of cariogenic foods and snacking between meals while gender differences were found for toothbrushing, flossing and consuming sweet foods. The need to target older adults and especially older males for oral hygiene information and instruction in order to counteract possible misleading beliefs learned before the advent of current dental hygiene practices is apparent from these data.

Age Factors↗

PubMed1992

The burden of oral disorders in a population of older adults.

This paper describes the burden of oral disorders in a population of adults aged 50 years and over living independently in the community. In so doing it uses clinical, functional, experiential and psychosocial impact measures to document the oral health status of this section of the population. The data reveal that substantial proportions of subjects report that their quality of life was compromised in some way by oral problems. Although only 24.1 per cent were edentulous, 30.5 per cent were unable to chew one or more foods; 37.2 per cent reported oral or facial pain in the previous four weeks and 67.5 per cent experienced one or more other oral symptoms. One third reported problems with eating and communication--social interaction, 18.7 per cent worried a great deal about their oral health and 30.8 per cent were dissatisfied with some aspect of their oral health status. Income was consistently associated with all health status measures examined, demonstrating the scope of inequalities in oral health. In addition, regression analysis showed that low income groups had higher scores on a psychosocial impact scale after controlling for clinical, functional and experiential oral health indicators. The paper illustrates the utility of a model of disease and its consequences derived from the international classification of impairments, disabilities and handicaps in exploring oral health.

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PubMed1991

Self-reported fears (FSS-II) of subjects aged 50 years and over.

From studies of fears in children and adolescents, it was concluded that fears decrease with age and that girls show more fears than boys at the approach of adolescence. Community studies of adult fears as well as psychopathology have suggested a decrease in fears and phobic and anxiety symptoms with age. However, little is known of the distribution of fears in older adults. In view of this, the FSS-II was administered to a group of individuals aged 50 yr and over, as part of a larger epidemiological investigation of the oral health and treatment needs of older adults within Metropolitan Toronto. The results supported the hypothesis that the gender differences which ermerge at adolescence hold up into old age. The predicted age decrease in fearfulness was also supported.

Adolescent↗

PubMed1991

Dental fear and anxiety in an older adult population.

A random sample of 580 people aged between 50 and 89 yr completed a questionnaire containing two measures of dental fear and anxiety. One of these was Corah's Dental Anxiety Scale (DAS) and the other a scale derived from the Structured Interview for Assessing Dental Fear (SIADF). The mean score on the DAS was 7.8, and 8.4% of subjects were classified as dentally anxious. There were no differences in mean DAS scores by sex but significant differences by age, with younger individuals having higher scores (P less than 0.0001). The edentulous had significantly higher scores than the dentate (P less than 0.001). Scores on the SIADF scale were higher among younger individuals (P less than 0.0001), the edentulous (P less than 0.01) and women (P less than 0.05). Older adults who were dentally anxious were less likely to report a regular source of dental care and a dental visit in the previous year and more likely to report having avoided or delayed dental treatment. Possible explanations of higher dental anxiety scores among younger persons and the edentulous are reviewed.

Age Factors↗

PubMed1991

Correlates of dental anxiety among older adults.

This paper reports on a study of dental anxiety among adults aged 50 years and over living independently in two communities in Ontario, Canada. Subjects were identified by means of a telephone survey based on random-digit dialing. Data on dental anxiety were collected from 580 subjects by means of a self-completed questionnaire and were measured by the Dental Anxiety Scale (DAS) (Corah, 1969). The mean DAS score was 7.8, and 8.4% of subjects were classified as dentally anxious. Age was the only demographic factor associated with dental anxiety. Older individuals had lower DAS scores than younger individuals (p less than 0.0001). There was also a significant association between dental anxiety and general fearfulness measured by the Fear Survey Schedule II (Geer, 1965) (r = 0.31; p less than 0.001). A series of regression analyses revealed that dental anxiety was a significant predictor of a number of behavioral and oral health outcomes. While these results confirm that dental anxiety is less prevalent among older adults than in younger populations, it has a number of important consequences with respect to dental care provision.

Age Factors↗

PubMed1991

Utilization of dental services by older adults in four Ontario communities.

The elderly tend to use dental services less than most younger age groups. While the elderly's utilization rates may be rising, very low utilization by edentulous people depresses the overall rate for the group. We use data from the Ontario Study of the Oral Health of Older Adults to identify the variations in the use of dental services in the four study sites of Toronto, North York, Simcoe County and Sudbury and District. We reached 3,033 subjects by telephone and conducted dental examinations and a multi-item personal interview with 907 of them. The 907 subjects ranged in age from 50 to 87 years, 57 percent were female and two-thirds were born in Canada. Overall, 60.5 percent had seen a dentist or denturist in the previous year, but this was much lower among the edentulous (17 percent) when compared to the dentate (72 percent) (Chi-square test; p less than .0001). Of the 357 who did not visit a dentist or denturist in the previous year, nearly half (48 percent) felt they had nothing wrong and 20 percent reported they could not afford care. A high proportion (94 percent) of the edentulous reported visiting only for pain or trouble compared to 26 percent of the dentate (Chi-square test; p less than .0001). Using logistic regression, we found dental status (edentulous), community of residence (Sudbury), income (up to $20,000) and dental insurance coverage (none) were important factors in not making a dental visit in the last year. These same factors, plus education (elementary) were important where subjects reported visiting a dentist or denturist only when there was pain or trouble.

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