HOOTH LOSS AND RISK FACTORS AMONG ELDERLY VIETNAMESE
often than anterior teeth. This finding is expected because of the morphology of the occlusal surfaces of posterior teeth, which easily accumulates plaque and food debris. Furthermore, it was often difficult for the elders to perform oral hygiene on the last position of the dental arch, and this could increase the risk of caries and periodontitis, leading to tooth loss. We observed that the prevalence of losing canine and posterior teeth of the maxilla were statistically higher than that of the mandible. The maxilla is known as the spongy bone type, and the mandibular is of the compact bone type; consequently, inflammation of the supporting bone in the maxilla could lead to a more rapid resorption of bone and earlier tooth loss than in the mandibular 12. However, our finding was in contrast with the study of Nguyen et al. 11, which indicated that loss of lower posterior teeth was more frequent than that of upper posterior teeth.
The elderly Vietnamese had an average of 7.6 missing teeth. At the same age group, this observed number is higher compared to the study conducted in Australia( 5.3) 13, Turkey( 7.0) 14, but lower than the one reported in China( 11.2) 8, and Brazil( 26.1) 15. Regarding the influence of sociodemographic factors on tooth loss, participants aged 70 – 74 had lost significantly more teeth on average than those aged 65 – 69. This finding was in agreement with previous studies, which indicated that the number of lost teeth tends to increase with age 14, 15. Maintaining more than 20 teeth is a core mission of Oral health care programmes for the older population 16. Approximately 60 % of the elderly Vietnamese still had 20 teeth or more. This prevalence was far lower compared with the findings in a neighbouring country 17, but in line with a study conducted in Iran 18, and higher than the ones reported in Turkey 14.
Table 1. The odds of > 6 lost teeth in relation to risk factors
Variables Frequency of cleaning teeth
Time in education
Tobacco smoking
Drink alcohol
Binary logistic regression Ref: reference, * p < 0.01
|
Odds ratio |
|
OR |
95 % CI |
p-value |
≥2 times / day 1.0( ref) ≤1 time / day 1.4 0.8-2.7 0.15
> 5 years 1.0( ref) ≤5 years 2.2 1.3 – 3.8 0.004 *
No 1.0( ref) Yes 2.8 1.4 – 5.6 0.003 *
No 1.0( ref) Yes 0.3 0.1 – 0.7 0.003 *
Rural residents had significantly higher tooth loss than urban residents. This reflected the difference in oral health services among regions in Vietnam where the density of dentists in the rural area was much lower than in the urban area( 1 / 200,000 for rural vs. 1 / 13,500 inhabitants for urban) 11. Moreover, the elderly Vietnamese living in a rural area often prefer to remove a painful tooth rather than having it restored because they think that tooth loss is a natural part of the aging process. The frequency of dental visits reflect the attitudes of the patient or the provider, accessibility to dental care and prevailing societal attitudes regarding oral health care. We found that 74.6 % of the elderly Vietnamese ignored an oral health checkup during the previous year, they only visited dentists with the unique aim to remove teeth due to an acute toothache or an impaired ability to chew( i. e. mobility teeth). Moreover, material and transportation-related obstacles, especially in the rural areas, are also factors that limit access to oral health care services 19, 20. Therefore, the number of teeth lost in this group was much higher than those who annually visited the dentist for oral care. Our finding was close to the third China National
Oral Health Survey. This survey reported that more than three-fourths of the Chinese aged 65 – 74 had missing teeth more often than those who regularly visited a dentist 8. The risk factors for tooth loss have been studied all over the world. However, as far as we know, no data have been reported on the risk factors of tooth loss in Vietnam. Lack of knowledge among the elderly Vietnamese regarding oral health might be influenced by the level of education 21. Forty percent of the elderly Vietnamese in the current study who were in education ≤5 years had lost 10.2 teeth on average. Their education might have been interrupted due to the Vietnam War( 1945 – 1975). The subjects believe that the prolonging the existence of a tooth in their mouth would have an adverse impact on the life of their descendants. Also, the elders with less time in education were significantly associated with the odds of losing > 6 teeth( OR = 2.2), it might be due to the lack of awareness about oral health behaviours for maintaining teeth. In the current study, we found that smokers( 23.4 %) had significantly higher tooth loss( 9.3 ± 7.6) than non-smokers( 7.2 ± 6.8). It could be due to the well-
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