During the last 10-20 yr there has been a marked increase in demand for dental services in most western countries. An important issue is how this increase in demand has influenced inequalities in use of services among different income groups in the population. It is of particular interest to study this in Norway, as almost all the costs for dental care among adults are borne by the patient. The aim of the present study was to examine how the effect of family income on demand for dental services has changed over time. The analyses were performed on three sets of national data from 1977, 1983, and 1989. The samples were representative of the non-institutionalized Norwegian population aged 20 yr and above. Inequalities in use of dental services among different income groups have decreased between 1977 and 1989. However, separate analyses on the data from 1989 showed that some inequalities still exist. A non-selective subsidizing policy for dental care is unlikely to have any great effect in reducing these inequalities. Subsidized dental care is likely to raise the total amount of dental care demanded. However, it is difficult to assess accurately the size of this increase as the elasticity of demand for dental care in Norway with respect to price is unknown.
OBJECTIVES: To assess, in a young population (age 6-19) managed by a restrictive attitude to radiography and operative intervention, prevalence of patients with posterior caries and/or fillings, probabilities of new proximal dentine lesions given different caries experience, correlation between radiographic intervals and caries experience, and prevalence of endodontic treatment. METHODS: Bitewing radiographs, taken between age 6 through 19 in 285 patients, were analysed in succession. Occlusal and proximal surfaces were coded for caries depth (0-4) and presence of fillings (5). Simple regression analysis was used to determine relations between radiographic intervals and caries experience. Significance testings of probability estimates were made with chi(2)- and t-tests, when applicable adjusted by the Bonferroni-Holm correction for mass-significance. RESULTS: The prevalence of patients with >/ or =1 fillings/dentine lesions in occlusal surfaces increased from 6-78% and in proximal ones from 1-38%. The probability of developing new proximal dentine lesions/fillings over different time periods was significantly lower among caries-free patients than among those with enamel or dentine lesions. There was a poor correlation between radiographic intervals (mean=16 months, range=6-33) and accumulated caries experience. Endodontic treatment had been made in a total of six teeth in six patients. CONCLUSIONS: A restrictive attitude both to the frequency with which radiographs are taken and to operative treatment of proximal caries seems to be possible in young populations with low caries prevalence.
OBJECTIVES: To longitudinally assess the distribution of fillings and carious lesions in permanent posterior tooth surfaces, caries states fillings were made, and survival time of proximal lesions in different states in a young population managed by minimal operative treatment and a restrictive attitude to radiography. METHODS: Bitewing radiographs from age 6-20 in 285 patients were analysed. Proximal and occlusal surfaces were coded for caries depth and fillings. Start and end dates for different caries states in proximal surfaces were assigned and survival times in these states calculated by means of survival statistics. RESULTS: The frequency of carious/filled occlusal surfaces in the population increased from 6 to 19% and that of proximal surfaces from 1 to 26%. At age 19, 86% of the occlusal and 7% of the proximal surfaces affected by caries were filled. An overwhelming majority of unfilled carious proximal surfaces had enamel lesions only. Of all fillings, 81% were placed in surfaces with dentine lesions. The occlusal and proximal surfaces of the first molar and the distal surface of the second premolar accounted for most lesions and fillings among the 19-year-olds. The average survival time of lesions in the enamel was 8.0 years and in the outer half of the dentine 3.4 years when right-censored data were taken into account. CONCLUSION: In a young population exposed to optimal levels of fluoride with a caries preventive programme, a restrictive attitude towards operative treatment can be combined with longer average intervals between radiographic examinations than those prescribed by current guidelines.