In the present study the prevalence of white spot lesions (initial enamel lesions) on the vestibular surfaces was recorded in 19-year-olds subjected to and not subjected to orthodontic treatment. Fifty-one orthodontic patients and 47 untreated subjects were examined. On the average, 5.7 years had elapsed since orthodontic appliances were removed. The median white spot score was significantly higher in the orthodontic group than in the untreated group. The orthodontically treated subjects also had more teeth with white spot lesions than the untreated subjects. The highest prevalence was noted on the first molars in both groups. In the orthodontic group the mandibular canines and premolars and the maxillary lateral incisors were also affected. The present study showed that white spot lesions after orthodontic treatment with fixed appliances may present an esthetic problem, even more than 5 years after treatment.
The article presents data from National Institute of Health on the prevalence of dental caries in 5-17 year olds in 1986-87 in USA. The data were compared with a previous study from 1979-80. Almost 50% of the children had no caries experience in 1986-87 compared with 36% in 1979-80. The DMFS data showed a reduction of about 36%, the mean for 1979-80 and 1986-87 being 4.77 and 3.07, respectively. The survey results showed that decay on the smooth surfaces of teeth, the surfaces that benefit most from fluoride, is disappearing. Today, two-thirds of caries is found on the occlusal surfaces of teeth. In Norway, the percentage of 5-year-olds without caries experience and mean DMFT in 12- and 18-year-olds have been registered since 1984. The American data are therefore not easily comparable with the situation in Norway. However, the mean DMFS values in 18-year-olds is hardly less than 13, whereas the average DMFS value of US 17-year-olds in 1986-87 was 8.04. The NIDR survey did not address the question of what is causing the decline in dental caries. The most likely reason is the widespread use of fluoride and in particular use of fluoride dentifrices. Fluoride dentifrices were introduced on the American marked in the 1950s, and in Norway in 1971. It is speculated that a further decline in dental caries may be expected also in Norway.
The present study was conducted to examine the incidence and location of filled surfaces from 10-18 years of age in individuals subjected to and not subjected to treatment with fixed orthodontic appliances. Each group comprised 65 individuals. About 5 years had elapsed since the appliances were removed. No statistically significant difference in filled surfaces was found between the groups at age 10 to 18. The incidence in filled surfaces from 10-18 years was 6.34 in the orthodontic group, and 7.22 in the untreated group. The difference was not statistically significant. The distribution of fillings in the dentition in the two groups showed no significant differences. Most of the fillings were recorded in the fissures of the molars. In the first molars most of the fillings in the fissures were already present at the age of 10. It was concluded that in individuals with relatively low caries activity, the present fluoride regimes are sufficient to prevent any excess caries lesion development requiring filling during or after orthodontic therapy.
Dummy- and finger-sucking habits were investigated among 60 5 year olds, born in 1982. The children were living in Raufoss, a small rural community in eastern part of Norway. Information about the sucking habits was obtained from their parents by means of questionnaires. The position of the teeth and the occlusion were registered by an orthodontist. Total prevalence of sucking habits was 63%. Thirty-seven percent, had used a dummy and 30% had been or were still finger-suckers. Two children had both used a dummy and sucked their fingers. This is a significant lower total prevalence of sucking habits than recorded in recent Swedish and Danish studies (1-8), but comparable with a Swedish study from 1971 (9). Most dummy-suckers had broken their habits at 3-4 years of age, while the finger-suckers were still active at 5 years of age. Finger-sucking had the largest impact on the position of the front teeth. The finger-suckers had significantly larger overjet and smaller overbite, more proclined upper incisors and retroclined lower incisors than dummy-suckers and those without any sucking habit. The only measurable effect of previous dummy-sucking of 5 years of age was a more open position of the lips and a smaller overbite. Otherwise, no significant effect on the occlusion was observed in any of the dummy- or fingersuckers.
The orthodontic service in Norway is mainly performed in private practices. However, in Oppland county, in the eastern part of Norway, there are several public orthodontic clinics. Financial support for orthodontic treatment is minimal whether carried out by private or public orthodontists. The public dentist has the main responsibility for diagnosing. The present study was conducted to examine the collaboration between general public dentists and orthodontists in Oppland county. The study was based on telephone interviews with 48 dentists. More than 90% of the dentists claimed that the orthodontic services in their district was sufficient. 81% felt that there was no orthodontic overtreatment. Written contact with the orthodontist was more common than oral communication (telephone). 31% of the dentists had weekly contact with the orthodontist, and 50% had monthly contact with the orthodontist. One third of the dentists expressed a desire for regular meetings with the orthodontist. Nearly two-thirds of the dentists preferred the orthodontist having the responsibility of diagnosing malocclusions. 81% were well satisfied with the treatment results. 63% rarely observed adverse effects of orthodontic treatment. The most common indications for recommending orthodontic treatment were functional disorders and prophylactic measures, and 65% considered the esthetic aspect of a malocclusion less important when referring a patient to an orthodontist. 62% felt that the financial support for orthodontic treatment in Norway today was unsatisfactory. 42% of those interviewed were of the opinion, that orthodontic services should be free, whereas 54% thought that orthodontic services should be only partly subsidized.
The present study reports on the prevalence of hypodontia in a Norwegian population and classifies children with hypodontia according to need of orthodontic treatment. Orthopantomograms of 1953 children (960 girls and 993 boys) at the age of 9 were available for examination. Of the boys registered with hypodontia of second premolars at the age of 9, 11.3% showed late mineralization between the ages of 9 and 12. Only 2.9% of the girls showed late mineralization. The corrected prevalence of hypodontia, excluding third molars, in the girls was 7.2%, in the boys 5.8%, and in both sexes combined 6.5%, the difference between sexes not being statistically significant. Of the children with hypodontia, 86.6% lacked only one or two permanent teeth. The most frequently missing teeth were the mandibular second premolars, the maxillary second premolars, and the maxillary lateral incisors, in that order. Classification of children with hypodontia according to need of orthodontic treatment showed that about two-thirds had hypodontia only of single posterior teeth with a moderate need of treatment. About one-third had hypodontia involving anterior teeth, and only 3.1% had hypodontia of two or more teeth in the same quadrant with a great need of treatment.
The present study investigated whether the incidence or prevalence of filled teeth/approximal surfaces at one age could be predictive for the incidence in another period or for the prevalence at the age of 18. The study was conducted in 12-18-yr-olds in Norway. Regression analysis showed that the best prognosis for subsequent incidence of filled teeth/approximal surfaces could be made at the age of 15. By using regression analysis or discriminant analysis it was possible at the age of 15 to predict with high accuracy those who would acquire more fillings than the median at the age of 18. Discriminant analysis with one predictor variable is suggested for clinical use. The variable that discriminated best between above and below median number of new fillings in the period 15-18 yr was untreated lesions in the inner half of the enamel in the approximal surfaces of premolars and molars at the age of 15. From the use of simple prediction tools, it was concluded that individuals at the age of 15 with a low prevalence of filled teeth/filled approximal surfaces and without untreated approximal lesions would be subjected to a low incidence of new fillings until the age of 18.
The caries status was recorded for 107 patients in a Norwegian psychiatric hospital in 1988. The number of edentulous patients was highest among patients older than 50 years (42%). Only two patients below 50 years of age were edentulous (5%). The average DMFT was 21.5 in the age group below 50 years and 26.8 in the age group above 50 years. The percentage number of patients with carious teeth (DT greater than 0) was 42% in those above 50 years and 60% in those below 50 years of age. On average, each patients used nearly 3 medicaments regularly. Most of the medicaments belonged to the antidepressiva and neuroleptica group which give nearly complete xerostomia. It is speculated that the reason for the high caries activity in the hospitalized psychiatric patients is due to irregular eating and oral hygiene habits in combination with complete or partial xerostomia. It is suggested that fluoride therapy (topical and tablets) and professional plaque control would be the most appropriate preventive measures.