Water fluoridation has not been introduced in Norway, although 99% of the population receive water with suboptimal fluoride levels. Alternative methods of fluoride prophylaxis have gained wide acceptance in this country. While less than 1% of the children received fluoride tablet in 1971, sales data in 1976 indicated a daily supply of fluoride tablets to 50% of the 0-5-year-olds and to 20% of the 6-11-year-olds. Most schoolchildren have joined mass prophylactic programs with regular with regular applications of fluoride solutions. Furthermore, fluoride-containing dentifrices have become available and are increasingly used. The increased use of fluoride has been paralleled by a marked reduction in caries and restorative need. During the past 5 years, a reduction of about 45% in the number of fillings inserted in 6-17-year-old children has been noted. In some areas, a 70% reduction has been recorded. The ratio between expenses for prophylaxis and savings in cost of treatment is favorable. The Norwegian Adverse Drug Reaction Committe received 34 case reports of adverse effects ascribed to fluoride prophylaxis, from 1970 to 1977. None of the 25 follow-up studies performed, suggested fluoride to have been responsible for the reported symptoms. In Norway, the benefits of fluoride prophylaxis are becoming increasingly evident.
A distance exceeding 2 mm from the cementoenamel junction (CEJ) to the alveolar bone was observed on the proximal surfaces of the first molars of proportionally more 15-year-olds (101 subjects) than 13-year-olds (99 subjects). The measurements were performed on bitewing radiographs, and the methodologic error amounted to 3%. Recordings in excess of 2 mm were most frequent (0.27 and 0.23) for the distal surfaces of the maxillary molars.
The purpose of the present study was to determine whether the caries-preventive effect of school-based programs with fluoride (F) mouthrinsing or toothbrushing was evident at the end of a post-treatment follow-up period of 11 years. Two groups of subjects examined at 14 years of age (born in 1960), who had participated in fortnightly F rinsing (n = 52) or in F brushing 4-5 times a year at school (n = 50), were re-examined radiographically and completed a questionnaire at age 25 years. A comparison group of 25-year-olds (n = 51) was also included. Analyses of variance showed that the benefits of participation in school-based F programs seem to have been lost. It appears that these caries-preventive programs have delayed rather than prevented caries and that F toothpaste and other caries-preventive efforts have been insufficient to avert a substantial caries activity during the follow-up period.
In a retrospective survey the mean number of intact proximal surfaces on the first molars of 13-year-old children was found to increase from 2.6 to 4.8 following 7 years of a preventive program with fortnightly fluoride mouthrinsings (0.2% NaF). This improvement was significant and corresponded to a reduction of the totally filled surfaces from 30.0 to 16.6. Caries on the proximal surfaces on the first molars was assessed from bite-wing radiographs. Judged from interexaminer comparisons, the number of filled surfaces was a reliable parameter of the caries prevalence in 13-year-old children. In a group of 54 children aged 13 who participated in the preventive program, the caries experience on the proximal surfaces of the first molars was significantly associated with the total DMFS.
The purpose of this study was to evaluate factors related to caries in 6-17-year-olds in 2 groups of Norwegian counties between 1966 and 1983. The average number of surfaces filled and permanent teeth extracted due to caries declined in the 4 northern counties from 1967. An increase was recorded in the 7 southwestern counties until 1971, then a decline. In the 1960s significantly more surfaces were filled and teeth extracted in the north compared to the southwest. Based on intra-county comparisons, the decline in surfaces treated was greater in the north between 1967 and 1983; 5.4 +/- 0.4 vs 3.7 +/- 0.7, P
The caries increment (filled surfaces) from the ages 7 to 15 years were compared in children with three or fewer (low prevalence group) or eight or more filled surfaces (high prevalence group) at the age of 8. The children participated in a fortnightly fluoride mouthrinsing program (10 ml of 0.2% NaF). Following 8 years of dental treatment and caries prophylaxis, the caries increments were 11.4 (s.d. = 7.7, n = 23 subjects) and 17.1 (s.d. = 9.6, n = 39 subjects) surfaces, i.e. significantly different (t = 2.376). Significantly (t = 4.034) more fillings had been required in the high than in the low prevalence group (31.1 +/- 17.1 vs. 15.5 +/- 9.6). The "risk group" could be identified at the ages of 7 to 8 by high caries prevalence and high ratio fillings/caries increment. Social class and number of teeth accounted more for the initial caries prevalence than for the caries increment. Correlation analyses revealed a significant, but not strong (r = 0.50), association between caries prevalence at the age of 7 and increment of fillings.
The MFS of 14-year-old children in Lillehammer, Norway, were recorded in 1959, 1969, 1979, and 1984. The data were extracted from dental records of random samples of 76 children. The mean MFS was 34.1 in 1959 and 28.0, 13.8, and 7.5 the following years. The caries prevalence was reduced by 78% from 1959 to 1984. In 1959, 16.6 approximal surfaces were filled, but in 1984 only 1.3. Significantly fewer radiographically initial lesions were observed in 1984 than in 1979. The continual decrease in caries prevalence is related to various fluoride programs, fluoride dentifrices, decreased caries prevalence among preschool children, and an assumed decreased challenge.
The present study describes the treatment pattern of a group of 381 recruits aged 20 in 1959. All men had taken part in the school dental service to the age of 14; 41% continued with regular care, 33% reported occasional treatments (2--4 times), and 12% no care from the of 14 (Table 1). The mean number of decayed (primary and secondary lesions), filled, and extracted teeth was found to be close to 21 in the various treatment groups (Table 2). The findings indicate a mean DMFT between 16 and 20 in the regular treatment group. When the recruits were grouped according to treatment pattern and the number of decayed teeth, the mean number of filled teeth was close to 15 in the sub-grojps with regular treatment (Fig 2). The mean number of filled teeth in the regular treatment groupd may be used as parameter in future evaluations.
About 3000 refugees from Vietnam have come to Norway in the last 5 years. A survey, including a clinical and radiographic examination for caries and gingival health, was carried out on 142 refugees. They were aged from 2 to 18 years and were examined within 6 weeks of arrival in Norway. The mean dmfs score of subjects 2-5 years old was 23.9, for subjects 6-11, dmfs was 12.4 and DMFS 7.7, and for subjects 12-18, DMFS was 20.0. The dmf/DMF scores were mainly composed of caries grades 3 and 4 (dentin caries or caries with pulpal involvement), and teeth missing or indicated for extraction. Only eight subjects had restorations, and these were often of poor quality. All subjects over 6 years had gingivitis (GBI 62%). About 10% had enamel hypoplasias on permanent anterior teeth. Dental abscesses and periapical areas indicated an acute treatment need, and most subjects were in urgent need of restorative treatment. Average time required for treatment of 12-18-year-old patients is estimated to be 7-10 hours, about four times that required for Norwegian schoolchildren. Dental examination of newly arrived Vietnamese refugees is recommended.