5.14.2 Data sources

 

 

Data were collected from national, regional or local oral health surveys or in specific communities including sample registration systems, surveillance systems, national survey data, and literature review. Major sources of information are the WHO Global Oral Data Bank (WHO, 2008), the CECDO Database (CECDO, 2008), ministries of health and scientific reports from population studies on oral health carried out in various countries. A total of more than 1,890 scientifically validated studies are contained in the WHO database but the fact that these surveys have more local or regional rather than national representativeness somewhat limits their impact. Oral health surveys were based on nationally representative samples. The data stored in the databank are updated regularly and the WHO GODB is currently linked with new information’s systems for surveillance of chronic disease and risk factors (Petersen et al, 2005). Few countries in Western Europe have established a data collection system at the national level: only United Kingdom has secular epidemiological data on the prevalence of caries in young children, adolescents and adults (Bourgeois, 2004). In Scandinavia, oral health information’s systems are an integral part of health services system. In Denmark, an advanced computer system has been established for children whereas surveillance of the oral health of the adult population is based on integrated chronic questionnaire schemes. In France, Germany, Spain, a series of surveys have been conducted on random sample of children, adolescents, adults age group and elderly. The tradition of surveillance is less developed in southern and Eastern Europe but progress have been established recently in Hungary, Poland and Portugal.

 

The indicators, issue from the EGOHID I project (www.egohid.eu), identified for this document are:

a. Decay Experience in Permanent Molars in Children

Mean number of decayed, missing and filled permanent molars present per children at 6 and 12 years of age.

Numerator: Total number of decayed (specify diagnostic threshold), missing and filled permanent molars present per children at 6 and 12 years of age.

Denominator: Total number of children at 6 and 12 years of age surveyed.

 

b. Dental Contact within the Previous Twelve Months

Proportion of population aged 2 and over who visited the dentist or dental clinic within the past year.

Numerator: Number of subjects aged 2 and over who visited a dentist or dental clinic within the past years.

Denominator: Total number of subjects aged 2 and over surveyed.

The question to be asked should be: When did you last visit a dental professional about your teeth, dentures or gums?

 

c. Periodontal Health Assessment

Proportion of population in the age group 12, 15, 18 and 35-44 and 65-74 years in the four categories: healthy periodontium, gingivitis only, periodontal pockets of from 4mm - 6 mm, periodontal pockets of 6 mm or deeper.

Numerator: Number of individuals in the age group 12, 15, 18 and 35-74 years in each of the four categories.

Denominator: Number of individuals in the age group 12, 15, 18 and 35-74 years examined.

Only bleeding status is recommended at age 12 and 15.

 

d. Edentulous Prevalence

Proportion of adult population aged more than 35 years who have lost all their natural teeth.

Numerator: Number of adults aged more than 35 years who have lost all their natural teeth.

Denominator: Number of adults surveyed.

 

e. Dentists and Other Oral Care Clinical Providers

The number and rates (per 100,000 population) of active dentists, dental hygienists, oral health therapists and clinical dental technicians.

Numerator: Number of active dentists and other oral care clinical providers per 100,000 population.

Denominator: Mid-year population.

 

Methods

The international epidemiological monitoring of oral health is a relatively recent initiative. Many countries traditionally recorded the number and type de services provided i.e. the number of teeth extracted and number of filled of dental fillings, but not the outcomes, i.e. whether interventions contributed to health or not. Some western European countries have established outcome-oriented information’s systems, but neglected the processes. The development of more comprehensive data systems for improving the quality of oral health care and systems is encouraged.

Comparisons of the global frequency and distribution of dental caries are complicated by diagnostic criteria that differ from study to study, but a fall in the prevalence and severity of caries in permanent teeth has been seen in many developed countries over recent decades. Also, the rate of progression of the disease slows down with increased age. The disease is mainly found in specific teeth and tooth types in both primary and permanent teeth.

 

European Union has not been in a position to estimate the impact and burden of periodontal diseases and its determinants and risk factors on the morbidity rates and quality of life of the population. The prevalence of moderate to severe attachment loss in the general population remains unclear in many countries. The major reason is that the description of periodontal condition is difficult, due to the scarcity of data from national studies based on a representative sample of the population of the country. In addition, the variation in methodological aspects of epidemiological studies markedly limits comparisons between countries and regions. There is therefore a need to address this deficiency. Surveillance of periodontal diseases condition should encourage dental professionals, consumers, private and public health care financing agencies, and decision-makers authorities to adopt an evidence-based approach to periodontal services, in order to rationally control costs, help assure quality and favourable outcomes, and extend more affordable dental care to a wider public.

 

The WHO data bank is based on specific methods that are recommended in oral health epidemiology, themselves resulting from basic epidemiological methods. It seems that synthesis international articles i.e. Pubmed databases are the main sources used to proceed to a state analysis of trends. A critical analysis of the methodological criteria used published for the oral health period 1986-1996 underlined weaknesses in the evaluation of oral health trends: weaknesses in terms of methodology, quality control, and presentation of results. The interpretation and conclusions in public oral health are therefore limited. New and complementary trends should be recommended so as to improve the production of higher quality information in oral health epidemiology.

 

The expansion of oral epidemiology during the 1970s overcame the obvious shortcomings in terms of knowledge about the oral health status of populations even though developed actions mainly targeted school children. Collected data favoured cross-section studies with no repetitive character since their aim was not to target the cohorts. At this stage of the produced information analysis, research and development perspectives should focus on the setting up of a health monitoring and recording system and furthermore, on respecting the rules of results dissemination that should lie within a benchmark methodological framework.