3.4 Resultados de decoloración
3.5.1 Ajustes de las curvas cinéticas de adsorción
The longitudinal component of the Health Professionals Follow- Up Study allowed Joshipura, Willett and Douglass (1996) to look at data for those men who reported that they had lost five or more teeth in the 4 year interim between questionnaires. They found that there was a statistically significant reduction in the intake of fruit and vegetable intake, and specifically a greater reduction in the consumption of apples and pears in men who lost five or more teeth when compared with those who had lost no teeth (p=0.03).
2.3.2 Dental status and nutrition
2.3.2.1 Cross sectional studies
While Osterberg & Steen (1982) found statistically significant difference in the intake of vegetables amongst men, by degree of dental invalidity as defined by the Eichner Index (1955), no corresponding differences were found for nutrition in terms of nutrient intakes derived from structured dietary interviews. Likewise, Hailing et al (1988) found that middle aged women who bad more than 15 teeth consumed more fruit and vegetables than those with fewer teeth or who were edentulous but they apparently found no differences with respect to ascorbic acid intake from dietary history data. It is unfortunate that neither of these surveys included assessments of dietaiy fibre and only a limited range of fruit and vegetable related nutrients.
Joshipura, Willett and Douglass (1996) used a self completed food frequency questionnaire to eissess nutrient intake and bad the participants report the numbers of teeth they bad. Regression analysis, after adjusting for age, smoking, exercise and profession, tested for trends in the intake of fibre and carotene. Statistically significant differences were found by groupings of numbers of teeth for all comparisons (p<0.01) with those who bad more teeth consuming more nutrients. No differences were found for vitamin C intake. The intake of folic acid was not reported.
Krall, Hayes and Garcia (1998) in the U.S. Department of Veterans Affairs Dental Longitudinal Study of men used the same food frequency questionnaire as Joshipura, Willett and Douglass (1996). Unlike Joshipura, Willet and Douglass’s study, the men in Krall, Hayes and Garcia’s study (1998) received a dental examination by calibrated
examiners and were classified by numbers of teeth and presence of complete or removable dentures. Krall, Hayes and Garcia (1998) found that those men who had fewer than 14 natural teeth, distributed on either one or on both sides of the mouth, and who had no removable dentures consumed lower levels of fibre, carotene, vitamin A, and folic acid than those with intact dentitions (at least 28 natural teeth) and less than those who had one or two removable partial dentures (p<0.05) after adjusting for age, calories education, smoking status. No differences were found amongst the men for vitamin C intake.
Steele et al (1998) reporting on the results of the British National Diet and Nutrition Survey which used a 4 day weighed record found that there was no difference in the intake of dietaiy fibre, vitamin A, nor vitamin C by numbers of teeth after controlling for socioeconomic and demographic characteristics. In addition, no differences were found in the intake of vitamin A and vitamin C by numbers of occluding pairs of teeth nor by posterior occluding pairs of teeth. However, there were statistically significant differences (p<0.05) found for the intake of dietary fibre when data were analyzed by numbers of occluding pairs of teeth and posterior occluding pairs of teeth in favor of those with greater numbers of each. Unfortunately, smoking was not controlled for as Subar, Harlan and Mattson (1990) demonstrated that smokers had lower intakes of vitamin C, folate and vitamin A than non smokers.
2.3.1.2 Cohort studies
As described previously, the longitudinal component of the Health Professionals Follow-Up Study allowed Joshipura, Willett and Douglass (1996) to look at data for those men who reported that they lost five or more teeth in the 4 year interim between questionnaires and those who lost no teeth. Joshipura, Willett and Douglass (1996) found that, while
there was a significant reduction in the intake of fruit and vegetables, and specifically a greater reduction in the consumption of apples and pears, in men who lost five or more teeth (p=0.03), changes in fibre and carotene intake were not significant.
2.3.3 Dental status and nutritional status
2.3.3.1 Cross sectional studies
The British National Diet and Nutrition Survey (Steele et al, 1998) was the only epidemiologic survey found in the literature that assessed the numbers of teeth and numbers of occluding pairs of teeth in relation to nutritional status. Steele et al (1998) observed that there was no statistically significant difference in the level of plasma ascorbate (vitamin C) and numbers of remaining teeth. However, a trend was found for the level of plasma ascorbate to increase as the numbers of OPs (p<0.05) and POPs (p<0.01) increased. The differences seen between the edentulous and dentate for retinol levels were not manifested by numbers of teeth, OPs or POPs, nor were there differences observed for vitamin E. As noted before, smoking status was not controlled for in the NDNS.
2.3.32 Summary
There is growing evidence from well conducted epidemiologic surveys from the United Kingdom, Nordic countries, and in studies amongst men in the United States, one of which included a longitudinal component, that the consumption of vegetables and fruit decreases with fewer teeth and numbers of occluding pairs of teeth and posterior pairs of teeth. It is unclear as to whether gender differences exist, as results are conflicting from study to study and the studies conducted in the United States have been exclusively with male participants. The evidence in
the majority of studies is that fibre intake is associated with the numbers of teeth as are carotene and possibly vitamin A and folic acid. The association between vitamin C intake and poorer oral health status amongst the edentulous were not reproduced in the studies of the declining numbers of teeth. No studies found a relationship between numbers of teeth and vitamin C intake. However, the one cross sectional survey that analyzed dentition status by numbers of occluding pairs and posterior occluding pairs of teeth did find differences in vitamin C intake levels in favor of those with more occluding units and likewise found this relationship manifested when blood analytes for vitamin C were assessed.
These findings are particularly relevant to the continuing discussions about the shortened dental arch concept and the numbers and position of teeth necessary to maintain a nutritious diet in aging populations. Evidence was not presented that would provide an indication at this time as to whether there is a lower limit to the numbers of posterior occluding pairs necessary. No differences were found for blood analytes of retinol or for vitamin E by numbers of teeth, OPs or POPs. Additional studies need to be conducted using both numbers of teeth, numbers of occluding pairs of teeth and numbers of posterior occluding pairs of teeth given the intriguing differences found between the two ways of quantifying dental status.
With respect to studies conducted in the United States, Joshipura, Willett and Douglass (1996) speculate that if future research were conducted in heterogeneous populations that include participants from a greater variety of socioeconomic backgrounds more pronounced differences in food choice may emerge. Joshipura, Willett & Douglass (1996) go on to acknowledge that their study did not include an
assessment of prostheses status and identify the need for studies to evaluate the role of prostheses in “facilitating consumption of a variety of foods”. What does the literature have to offer regarding studies related to dental prostheses and diet and nutrition?