5.4.1.1 F ood intake
5.4.1.1.1 N um bers of te e th a n d intake of carro ts
The mean reported number of intakes of carrots by United States adults aged 25 years and older with solely natural teeth was 7.1 per month (Table 5.4-2). The numbers of teeth were associated with the mean number of times carrots were eaten per month (p<0.0001. Table 5.4-3). As seen in both the unadjusted and adjusted models, when compared with the fully dentate all categories of numbers of teeth less than 28 had lower mean intakes of carrots per month and were statistically significant (p<0.05). Also, there was a clear trend for the mean intake of carrots to increase as the numbers of teeth increased with those who had the fewest teeth (1-10) reporting the lowest intake, less than half that of the fully dentate (2.30 versus 5.75, respectively). The mean
intake of those with 20 or more teeth (21-27) most closely approximated that of the fully dentate with, on average, one less intake of carrots per month (4.62 versus 5.75, respectively). The coefficients of determination were 0.005 and 0.07 for the unadjusted and adjusted models, respectively. The adjusted effect of numbers of teeth on the model was statistically significant (p=0.003).
5.4.1.1.2 N um bers of tee th an d intake of to s s e d s a la d s
The mean reported intake of tossed salad amongst those who had natural teeth was 8.9 times per month (Table 5.4-2) and there was an association between the mean numbers of teeth and tossed salad intake (p<0.0001) (Table 5.4-4). As with carrot intake those with the fewest teeth (1-10) had a mean intake of tossed salad that was considerably less than those with a full complement of teeth even after adjusting for potential confounders (6.16 versus 10.96, respectively, p=0.001). After adjusting for potential confounders the differences in mean intake of those with 11-20 and 21-27 teeth were statistically significantly different (p=0.04) from the fully dentate. The mean intakes were nearly 2 and 1 fewer per month (9.09 and 10.05, respectively). The variables in the unadjusted model explained 1 percent of the variance and with six additional variables in the adjusted model, 8 percent was explained. The adjusted effect of dental status remained statistically significant (p<0.0001).
5.4.1.1.3 N um bers of te e th a n d Intake of c itru s fruit
The reported intake of citrus fruit per month overall for those American adults with natural teeth was a mean of 7.5 (Table 5.4-2) and an association was found between dental status and citrus fruit intake (p<0.0001, Table 5.4-5). When looking at the results for reported intake of citrus fruit, a very different picture was seen from that of carrots and
tossed salad as both the unadjusted and adjusted findings indicated that the intake of citrus fruit for those with 1-10, 11-20 or 21-27 teeth when compared with the fully dentate were not different.
5.4.1.1.4 N um bers of te e th a n d intake of w hole grain o r w h o le w h eat bread
The numbers of teeth that people had were associated with the percentage of people reporting eating whole grain or whole wheat bread during the previous 24 hours (p<0.0001, Table 5.4-6). While no statistically significant differences were found between those with more than 20 teeth and the fully dentate in the unadjusted and adjusted models, statistically significant (p<0.0001) but small differences existed for those with more than 10 teeth (0.7% in the adjusted model). However, as seen in the results of the adjusted model, the difference in mean percentage intake between those with the fewest teeth (1-10) and the fully dentate was statistically significant (p=0.0001) and striking with nearly 18 percent fewer reporting an intake (6.22 to 24.25 percent, respectively). The coefficients of determination were 0.0003 and 0.05 for the unadjusted and adjusted models, respectively and the adjusted effect of dental status was statistically significant (p<0.0001).
5.4.1.2 N utrient intake
5.4.1.2.1 N um bers of te e th a n d intake of dietary fibre
The mean daily intake of dietary fibre for those with only natural teeth was 17.8 grams (Table 5.4-2). The numbers of teeth were associated with the number of grams of dietary fibre consumed (p<0.0001). Trends seen in the intake of carrots and tossed salad and the percentages of people reporting consumption of fibrous breads were clearly reflected in the reported mean intake of grams of dietary fibre before and after adjusting for potential confounders (Table 5.4-7). A difference in intake
of dietary fibre between those with a full complement of natural teeth and those with fewer teeth decreased monotonically, and ranged in the adjusted model from a 1.4 gram difference (p=0.03) for those with more than 20 teeth to a 4.7 gram difference (p=0.007) for those with 1-10 teeth. Numbers of teeth explained 2 percent of the variance and when the six covariates were added to the model, 11 percent of the variance was explained. The adjusted effect of numbers of teeth on the model was statistically significant (p=0.01).
5.4.1.3 Nutritional s ta tu s - biochem ical
5.4.1.3.1 N um bers of te e th an d se ru m b eta c a ro te n e levels
The mean level of serum beta carotene in United States adults who had only natural teeth was 19.0 ug/dL (Table 5.4-2). The numbers of teeth were associated with the level of serum beta carotene (p<0.0001, Table 5.4-8). Just as the intake of dietary fibre was reflective of the intake of food items, so too was the level of serum beta carotene, that is, the level increased monotonically from the fewest numbers of teeth (1-10 = 13.32 Ug/dL, p=0.04) to the greatest number (fully dentate= 18.65 ug/dL) in the adjusted model. In addition, as was seen with the food items and dietary fibre, the difference in mean scores was least amongst those with more than 20 teeth and the fully dentate, and in this case, the difference was not statistically significant after adjusting for potential confounders (p=0.06). The coefficient of determination was 0.004 and the multiple coefficient of determination was 0.14. The adjusted effect of numbers of teeth on the model was statistically significant (p=0.0006).
5.4.1.3.2 N um bers of te e th an d se ru m folate levels
Those Americans aged 25 years and older who had natural teeth had a mean serum folate level of 6.1 ng/dL (Table 5.4-2). The numbers of teeth were associated with the mean level of serum folate (p<0.0001,
Table 5.4-9). The findings in the unadjusted and adjusted models were similar, that is, statistically significant differences existed in the ng/dL of serum beta carotene amongst those who had 20 teeth or less when compared with the fully dentate (p < 0.05). The adjusted mean differences were 1.7 ng/dL lower for those with 1-10 teeth and 0.84 ng/dL for those who had 11-20 teeth. No statistically significant difference existed between those who had 21-27 and the fully dentate. The coefficient of determination was 0.001 for the unadjusted model and when the six covariates were added to the model it increased to 0.22. The adjusted effect of the numbers of teeth on the model was not statistically significant (p=0.08).
5.4.1.3.3 N um bers of te e th a n d se ru m vitam in C levels
The mean serum vitamin G level of those with natural teeth was 0.68 mg/dL (Table 5.4-2). A veiy different picture emerged for the relationship of numbers of teeth and serum vitamin C than that seen for reported intake of citrus fruit. The numbers of teeth were associated with the level of serum vitamin C (p<0.001. Table 5.4-10). The unadjusted model showed a clear trend for serum vitamin C levels to be progressively greater as the numbers of teeth increased. This trend was sustained even after adjusting for age, gender, race / ethnicity, socioeconomic status, smoking, vitamin and mineral supplement use, and the intake of citrus juice. When pairwise comparisons were made between the number of teeth and the fully dentate the results were highly statistically significant even in the adjusted results. People with 1-10 natural teeth had mean levels of serum vitamin C which were on average 0.26 mg/dL lower than that of the fully dentate, and the differences for those with 11-20 and 21-27 teeth were 0.11 and 0.05 mg/dL lower than for the fully dentate, respectively. The bivariate model explained 2 percent of the variance and the multivariate model
explained 20 percent. The adjusted effect of numbers of teeth on the model was statistically significant (p=0.0006).
5.4.1.4 Nutritional s ta tu s - a n th ro p o m etric
5.4.1.4.1 N um bers o f te e th a n d B ody M ass Index
The mean Body Mass Index Score for those with only natural teeth was 27.4 (Table 5.4-2) and the number of teeth was associated with the Body Mass Index ( p<0.0001, Table 5.4-11). The results of the unadjusted and adjusted analyses presented a picture dissimilar to that seen in analyses of food items, dietary fibre, and blood analytes. No difference existed between those with the fewest teeth (1-10) and those who were fully dentate with respect to their Body Mass Index either before or after adjusting for the effects of potential confounders (p=0.6 and 0.08, respectively). In addition, whereas there was a positive association between the intake of food items and dietary fibre, and levels of blood nutrient levels and the number of teeth, an inverse relationship existed between BMI and those who had 11-20 or 21 - 27 teeth emd those who were fully dentate with the latter having on average lower BMI scores (25.3, 24.5, 23.8 respectively) (p=0.0005 and 0.001, respectively). The bivariate model explained 2 percent of the variance and the multivariate model explained 5 percent. The adjusted effect of numbers of teeth was statistically significant (p<0.0001).