Case study 3
2.2 Severe periodontal disease
2.2.1 Global burden of severe periodontal disease
Severe periodontal disease (see Box 7 for definition) is widespread, with a global prevalence of about 19% in people aged greater than 15 years, representing more than 1 billion cases worldwide.Prevalence across country income groups is similar, yet case numbers are highest in lower-middle-income countries (437 million) and lowest in low-income countries (80 million; see Fig. 22 and Table 6). Prevalence of severe periodontal disease starts in late adolescence, peaks around 55 years of age and remains high until old age.
Men and women are almost equally affected (88, 89). Fig. 23 provides an overview of prevalence per country.
©WHO
Box 7.
What is severe periodontal disease?Periodontal disease is a chronic inflammation of the soft and hard tissues that support and anchor the teeth. Periodontal diseases include gingivitis (gum disease), a superficial and reversible inflammation of the gum resulting in swelling and bleeding. In the presence of other accelerating factors, such as tobacco use, systemic diseases or a compromised
immune response, gingivitis may develop into periodontitis, thereby affecting the deeper gum tissues and bone. The loss of attachment (“pocket”) eventually leads to increased mobility and tooth loss. Only severe periodontal disease, defined as the presence of a pocket of more than 6 mm depth, is a condition of public health concern (4, 89).
Fig. 22. Estimated cases and prevalence of severe periodontal disease per WB country income group
Note. Data are age standardized, for ages greater than 15 years, both sexes, from GBD 2019 (4).
Table 6. Estimated prevalence and cases of severe periodontal disease in 2019 and the percentage change of prevalence, cases and population from 1990 to 2019 per World Bank income group
WB income group Prevalence
(2019) Cases (2019)
Percentage change prevalence
(1990–2019)
Percentage change cases
(1990–2019)
Percentage change population
(1990–2019) a
Low income 19.71% 80 008 079 0.73% 129.75% 117.98%
Lower-middle income 19.80% 436 697 336 17.24% 124.66% 63.25%
Upper-middle income 18.19% 386 443 138 34.98% 96.83% 27.97%
High income 17.65% 176 251 937 18.71% 51.43% 20.63%
Global 18.82% 1 079 927 025 23.96% 99.18% 44.79%
Note. Data are age standardized, for ages greater than 15 years, both sexes, from GBD 2019 and UN DESA 2019 (4, 7).
a Population numbers are for total population across all age groups.
Fig. 23. Estimated prevalence of severe periodontal disease per country
Estimated
prevalence of severe periodontal disease in people 15 years+, 2019 2.9% - 10.6%
10.6% - 19.6%
19.6% - 27.3%
27.3% - 36.7%
Data not available Not applicable
Data source: Global Burden of Disease Collaborative Network. GBD 2019. Seattle: IHME; 2020. Map Production: WHO NCD/MND unit. Map Creation Date: 30 August 2022. Note. N = 194 countries; data are age standardized, for ages greater than 15 years, both sexes, from GBD 2019 (4).
Among the WHO regions, prevalence ranges in a narrow band between 16% (Western Pacific Region) and 23% (African Region), while the case numbers reflect the demographic share of the respective regions, with the South-East Asia Region and Western Pacific Region showing the highest case numbers and the Eastern Mediterranean Region showing the lowest (see Fig. 24 and Table 7).
Fig. 24. Estimated cases and prevalence of severe periodontal disease per WHO region
Note. Data are age standardized, for ages greater than 15 years, both sexes, from GBD 2019 (4).
Table 7. Estimated prevalence and cases of severe periodontal disease in 2019 and the percentage change of prevalence, cases and population from 1990 to 2019 per WHO region
WHO region Prevalence
(2019) Cases (2019)
Percentage change prevalence
(1990–2019)
Percentage change cases
(1990–2019)
Percentage change population
(1990–2019) a
African Region 22.80% 144 745 633 2.47% 136.93% 114.98%
Eastern Mediterranean
Region 17.37% 82 864 263 10.42% 149.44% 93.08%
European Region 17.89% 136 209 156 16.13% 34.14% 9.94%
Region of the Americas 18.89% 148 617 765 19.74% 89.37% 40.70%
South-East Asia Region 20.77% 306 964 138 22.66% 125.95% 52.38%
Western Pacific Region 16.28% 258 963 653 39.19% 97.51% 24.96%
Global 18.82% 1 079 927 025 23.96% 99.18% 44.79%
Note. Data are age standardized, for ages greater than 15 years, both sexes, from GBD 2019 and UN DESA 2019.
a Population numbers are for total population across all age groups.
2.2.2 Trends in disease burden 1990–2019
Prevalence and case numbers of severe periodontal disease increased significantly between 1990 and 2019. Estimated case numbers increased by almost 540 million, while estimated prevalence increased by 24%. Upper-middle-income countries showed the highest increase in prevalence (35%); the group of low-income countries was estimated to have almost no change in prevalence. Case numbers, however, increased the most in this country group (130%), as opposed to high-income countries with the smallest increase in case numbers (51%; see Table 6).
Among the WHO regions, the Western Pacific Region had the highest increase in prevalence between 1990 and 2019, while the highest increase in case numbers was estimated for the Eastern Mediterranean Region (see Table 7).
Prevalence of severe periodontitis increases with age (see Fig. 10). With the global demographic changes characterized by larger ageing populations and increasing longevity, an even higher global burden of severe periodontal disease may be expected in the future.
2.2.3 Severe periodontal disease, inequalities and general health
As for other NCDs, there are significant inequalities among population groups resulting from differences in exposure to risk factors and wider determinants of health. A greater disease burden is found in populations with lower socioeconomic status, income or education as well as among those living in rural areas. The consequences of severe periodontal disease for people affected include difficulties with eating or speaking, particularly when teeth are loose or already lost. Social interaction, general well-being and quality of life may also be significantly impaired.
Poor oral hygiene is a major behavioural risk factor for periodontal disease, together with common NCD risk factors such as tobacco use (90).
Severe periodontal disease is closely interlinked with major NCDs; particularly an association with unmanaged type 2 diabetes is well documented. Good periodontal health improves glycaemic control;
deterioration of periodontal health may be an early indicator of poorly managed diabetes (44, 91).