Estimated Tooth Loss Based on Number of Present Teeth in Japanese Adults Using National Surveys of Dental Disease

Abstract

Oral health instruction for adults should take into account the potential effect of tooth loss, as this has been suggested to predict further tooth loss. Therefore, the purpose of this study was to determine whether further tooth loss could be predicted from the number of present teeth (PT). We employed the same method as in our previous study, this time using two national surveys of dental disease, which were deemed to represent a generational cohort. Percentiles were estimated using the cumulative frequency distribution of PT from the two surveys. The first was a survey of 704 participants aged 50-59 years conducted in 2005, and the second was a survey of 747 participants aged 56-65 years conducted in 2011. The 1st to 100th percentiles of the number of PT were calculated for both age groups. Using these percentiles and a generational cohort analysis based on the two surveys, the number of teeth lost per year could be calculated. The distribution of number of teeth lost generated a convex curve. Peak tooth loss occurred at around 12-14 PT, with 0.54 teeth being lost per year. The percentage of teeth lost (per number of PT) increased as number of PT decreased. The results confirmed that tooth loss promotes further tooth loss. These data should be made available for use in adult oral health education.

How to Increase Number of Present Teeth in Elderly: Consideration of Percentile Curves for Present Teeth in Tokyo

“…In the 75th and 90th percentile curves, tooth loss accelerated when the number of present teeth was fewer than 25 in both 2009 and 2014. This finding is consistent with studies reporting that tooth loss itself is a risk factor for tooth loss 4,5,7,10,18,21,22) .…”

“…The causes of tooth loss are mainly caries, periodontal disease, trauma, and fracture 1,2,16) . In addition, tooth loss 4,5,7,10,18,21,22) and a decrease in occlusal support 7,15,20) have also been reported to be risks factors for tooth loss. As tooth loss is irreversible and increases with aging, the number of present teeth is frequently used as a measure in population-based epidemiological studies.…”

Tooth Loss in Problem-oriented, Irregular, and Regular Attenders at Dental Offices

“…It is well known that the risk of tooth loss increases as the number of PT decreases 4,14,31,33) . We believe greater awareness of this fact among the general public would encourage a change in behavior with regard to regularly visiting their dentist, which should help prevent further tooth loss.…”

Estimating tooth retention by the number of present teeth in a middle-old-aged population: 3-year follow-up study in Korea

“…In a nationwide cross-sectional study, Yoshino et al demonstrated an association between the number of present teeth and tooth loss over a period of 6 years. 24 A smaller number of teeth in subjects aged 50-59 years and 56-65 years were associated with greater tooth loss after 6 years. Similarly, Eklund et al reported that a higher percentage of subjects with fewer teeth became edentulous over a subsequent 10-year period, than did subjects with more teeth.…”

“…A previous study reported that the number of present teeth in individuals at the ages of 50-59 years and 56-65 years was associated with tooth loss 6 years later. 24 However, in that study, it was not possible to estimate future tooth retention from the number of present teeth at baseline, because the authors used 2 separate cross-sectional or longitudinal studies to examine the effect of present teeth on tooth loss, but did not investigate the issue from the perspective of tooth retention.…”