In sub-Saharan Africa, communicable diseases are still major threats to health but the burden of chronic diseases and injuries are expected to increase rapidly [1]. The epidemiological transition in relation to oral health is particularly apparent in the growing incidence of dental diseases such as caries and periodontal conditions. Other conditions such as oral cancer, oral manifestations of HIV/AIDS and dental trauma are also expected to increase in the near future [2].

In many African countries, the availability and accessibility of oral health services are seriously constrained, and the provision of essential oral care is limited. Many studies have been undertaken in industrialised countries to assess the level and the pattern of utilization of dental health services [3, 4]. Unfortunately, this has been a neglected field of research in Africa. The few existing reports from the region show very low utilization of oral health care services, and visits to a dental-care facility are mostly undertaken for symptomatic reasons [5–8]. A survey conducted in a peri-urban settlement of South Africa found that 37.0% of adults had consulted a dentist or medical practitioner, usually for tooth extractions [6]. A study in the Ivory Cost reported that only 11.4% of the city-dwellers in Abidjan had visited a dentist because of dental problems [7]. Another study in Nigeria showed that 9.0% of households had used dental services during the past year while variables such as "zone of residence" and "household educational and social class ranking" affected use of oral care services [8]. In Tanzania, the principal factors associated with the utilization of oral health care services were distance to treatment facility and previous dental symptoms [9]. Concomitantly, self-medication with herbal medicines or modern drugs seems to be a common practice in many African countries [10, 11].

Systematic studies of the utilization of oral health services and the factors involved in seeking health care are urgently needed so that oral health programmes may be developed to match the needs of the population. The objectives of the present study were to describe the prevalence of oral symptoms among urban adults and the use of oral health services and self-medication in response to these symptoms, and to analyze the associations between predisposing, enabling and needs factors and decisions about seeking oral health care. This study is part of a larger research programme carried out by the Institut de Recherche pour le Développement (IRD) to assess social and spatial health disparities in Ouagadougou.

Our data on urban people in Burkina Faso show that oral self-care is practised in accordance with both traditional and modern self-medication cultures. Impairment of function and poor quality of life are also observed in high proportions of individuals who claimed to have their usual activities restricted by oral problems. Moreover, we have identified socio-economic and socio-cultural factors as potentials barriers to the use of oral health facilities. Relatively little is known about oral health service utilization patterns among populations of African countries. The intention of the study was to analyse responses to illness episodes and oral health seeking behaviour among adult city-dwellers in a sub-Saharan country (Ouagadougou, Burkina Faso). In particular, an aim of this investigation was to evaluate the association between utilization of oral health facilities and certain predisposing, enabling and need barriers and facilitators.

In developing countries, random sampling is largely impossible because of the lack of census lists or valid population registers, so alternative procedures are needed to obtain representative samples. In irregular sub-areas, few sampling methods are available for surveying households. In the present study, we applied the "door-to-door" method used in the standard Expanded Program of Immunisation (EPI) developed by WHO [16]. Although this method suffers from a number of disadvantages and was initially developed to measure the coverage of the childhood immunization programmes and nutritional status, it has been widely and successfully used for other purposes in low income countries [19, 20]. Furthermore, the response rate is acceptable and only minor differences in socio-demographic profiles among participants and non-participants were noted. Despite the limitations, for those members of the study population who met the eligibility criteria for the study, the data allow reasonable inferences to be drawn about the factors most significantly associated with the use of dental services in the study area.

Studies examining the utilization of oral health care service have measured dependent variables in different ways [3]. The percentage of persons reporting or not reporting a visit to a dentist within the past year is one commonly used parameter for assessing the utilization of dental services. In the context of developing countries where dental visiting habits are primarily orientated towards relief of symptoms or pain rather than preventive care, it seems particularly relevant to express data concerning utilization by people who have experienced oral trouble within the past year.

Compared with western industrialized countries, where about 40–80% of the adults would have visited a dentist within one year [3, 4, 21], the use of professional oral health care services is alarmingly low in Ouagadougou and self-medication appeared to be an important alternative source of care for the participants in the present study. Despite differences in study design, this pattern accords with previous surveys carried out in Nigeria [8], Ivory Coast [7] and South Africa [6]. It is interesting to note that urban studies conducted in Burkina Faso [22] and in Congo [23] revealed that adults reporting general illness symptoms also had low attendance at professional health services while self care was common practice.

Our study also emphasises the association between religious affiliation and the use of health facilities. This somewhat surprising finding may reflect the historical basis of the implementation of health services in Ouagadougou since the colonial period. Christian missionaries (Protestant or Catholic communities) have played a major role in providing of health care [24]. In Ouagadougou, the current oral health care services are mainly provided by nongovernmental not-for-profit health centres run by missionaries [14]. Similarly, a relationship between religion and the utilization of maternal and child health services was found in a recent study in Ghana, a country that borders Burkina Faso [25]. The authors speculated that religion represents a social structural attribute that may influence patterns of maternal health utilization.

The socio-economic level of the household is a key determinant of health seeking behaviour [3, 26–28]. In our study, the socio-economic standard of the household was measured by a proxy index of material living conditions, which was strongly associated with the use of health care services. In addition, the bivariate analysis showed an association between the choice of oral health care and the regular settlements. The population groups living in irregular settlements were less likely to visit health professionals and also more likely not to seek treatment at all. The multivariate analysis did not confirm this pattern because of the inter-correlation between residential area and the index of material living conditions.

The perceived importance of oral health problems emerged as a significant factor in health service utilization in our study. It was not surprising that adults who paid less attention to oral diseases compared to general diseases were unlikely to seek health services. The perceived severity of symptoms was shown to be an essential determinant of treatment choice. This result is consistent with research showing that cultural beliefs and values may act to reinforce or inhibit the use of health services, depending upon the reference group values [4, 29]. Fear and anxiety are often suggested as barriers to use of dental services [30]. This was not the case in the present study, as those who were afraid of dentists were more likely to use dental services. This reflects the fact that dental visits are very unpleasant because the service often rendered for pain relief is extraction of teeth. This observation accords with findings about oral health service utilization among adults in China [31, 32].

Access to health care facilities seems to be less of a problem in urban than in rural areas, although travel expenditure tends to increase rapidly in a large city like Ouagadougou. Furthermore, it is worth noting that oral health services are limited and mainly established in the central part of the city [14]. This may help to explain why having a moped or other vehicle appeared to be an enabling factor in using oral health care facilities. Thus, although distance in the big cities of developing countries may not represent a major problem for access to general health facilities [22], it is still a potential barrier to the use of oral health services.

The present study also indicates that active participation in social networks is an important determinant of oral health seeking behaviour in the event of oral affliction. The social networks mechanisms consist of advising about or facilitating access to particular health providers. Furthermore, the number of years spent in the city or having been born in Ouagadougou were not associated with use of oral health services. This may suggest that use of oral health services depends more on participation in urban networks than on the duration of urban life experience. Such findings corroborate various oral health care utilization studies carried out in industrialized countries [3, 33]. Other studies conducted both in both developed and developing countries and focusing on general health seeking behaviour have also emphasized the influence of social networks as predictors of health care utilization [34, 35].

Our data on the urban adult population in Burkina Faso showed that oral self-care accords with both traditional and modern self-medication practices. Out-of-pocket expenses for health services in general and for oral health services in particular may lead to widespread self-medication among the populations of developing countries. In addition, socio-cultural factors have been identified as significant in relation to use of oral health services. These factors can help identify groups "at risk" and assist in planning public health intervention programs.

For most urban centres in sub-Saharan Africa, the capacity of the oral health system is still insufficient to match the needs of all individuals suffering from pain or discomfort and to serve the population at large, especially in deprived communities. National health authorities should explore critical issues concerning self-medication for the prevention and treatment of oral symptoms before promoting the potential benefits of affordable alternative sources of care. Furthermore, decision-makers must seek to ensure that access to essential oral health care is improved. Such initiatives should pay specific attention to the poorest population groups and thereby also facilitate their access to health services.