High consumption of fruit juices and carbonated drinks has been related to dental erosion. Teenage male Icelanders consume about 800 ml of carbonated drinks per day on average and this corresponds with the main age group and gender of patients seen with erosion. This study examined the prevalence of dental erosion in 15-year-old children in Reykjavík and looked at the association between erosion and some lifestyle factors in a case-control study drawn from the same sample. A 20% sample of the 15-year-cohort population (n = 278) was selected. Dental erosion was classified by location and severity (1 = enamel erosion; 2 = dentine erosion; 3 = severe dentine erosion) and was seen in 21.6% of subjects (68.3% male; 72% scored as grade 1; 23% grade 2; 5% grade 3). Control subjects were the first healthy subjects examined after a case subject had beens diagnosed. In the case-control study, information was gathered by multiple-choice questionnaire on symptoms of gastric reflux, tooth sensitivity, some lifestyle and dietar-factors. Several lifestyle and dietary factors, previously shown to be significantly related to dental caries in Icelandic teenagers, showed no significant relationship to tooth erosion. Although dietary factors are probably important in causing erosion, dietary recall questionnaires did not help in discovering individuals likely to develop erosion.

Dental erosion was frequently present by the age of 12; the prevalence doubled by age 15 and was seen almost twice as often among boys than girls. Teeth most frequently showing signs of erosion were the lower first molars. The rapidly growing prevalence of erosion demonstrated by this nationwide survey emphasizes the need for further research into the aetiology of erosion and possible methods of preventing and treating this emerging dental problem.

Caries levels were higher than expected in this national survey and further away from the goals of the National Health Plan for 2010 than anticipated. Caries distribution was skewed with more than half of the children having low caries scores but a wide distribution of caries experience was seen among the remaining population.

The oral and dental health of patients with Parkinson's disease (PD) has not been well documented and the findings are conflicting. Patients with PD were invited to take part in a clinical and radiographic examination together with a comparison control group of persons who were a spouse or family member. Subjects (n = 67) and controls (n = 55) were examined and compared. Subjects with PD had more missing teeth, caries, dental plaque, and poorer periodontal health. Counts of cariogenic bacteria in saliva were significantly higher for subjects with PD. They did not consume more sweets or sugar, did not brush less frequently, used dental floss more than controls, and visited the dentist at least as often. Salivary flow levels were comparable between subjects with PD and controls. The lack of muscular control may explain the poorer oral health of patients with PD. Dentists and patients with PD may be reluctant to embark on complex dental procedures, and this may explain the increased number of missing teeth in persons with PD in this study.

The aim of this study, conducted in 1994, was to examine the association between approximal caries and sugar consumption in teenagers residing in three fluoride-deficient areas in Iceland while controlling for a number of behavioral, residential and microbiological factors. One hundred and fifty subjects (mean age 14 years) selected from the Icelandic Nutritional Survey (INS) were examined radiographically and they completed questionnaires about sugar consumption frequency. Total grams of sugar intake were obtained from the INS for each subject. Caries experience on approximal surfaces, diagnosed from radiographs, was used as the dependent variable in the analyses. Altogether 45.2% of subjects were caries free on approximal surfaces. The overall sample was found to have a mean DFS on approximal surfaces of 2.73 (s=4.36) per subject. Average daily total sugar intake was 170 g per subject and the mean number of sugar-eating occasions between meals was 5.32 (s=6.29) per subject. The regression model indicated that the frequency of between-meal sugar consumption was associated with approximal caries, with frequency of candy consumption being the most important of the sugar variables. In multivariate analysis, no relationship was found between dental caries and total daily intake of sugar, although a significant relationship between total sugar consumption and presence of caries was seen in bivariate analysis. Between-meal consumption of sugar remains a risk factor for the occurrence of dental caries, especially in populations with moderate-to-high levels of dental caries experience.