Nitrous oxide-oxygen sedation in dental care.

The aim of this study was to evaluate the dental treatments under nitrous oxide-oxygen sedation carried out during 1 yr by the first 45 Swedish dentists trained at probationary courses in the use of the technique. Special emphasis was placed on evaluating the risk and incidence of side effects. Data from 1719 treatment sessions in 823 patients, mainly children, were analyzed. Standardized sedation technique was used and the maximum level of nitrous oxide administered was set at 60%. About 90% of the patients showed excellent or fair acceptance. Factors influencing the acceptance were the patient's age, history of psychiatric disorders, mental retardation and occurrence of side effects. In 4.5% of the treatment sessions the patient experienced side effects, e.g. restlessness, vomiting or nausea, during treatment and in 0.9% after the treatment session. The side effects were mainly mild. No correlation was found between side effects and the nitrous oxide concentration used, length of treatment, patient's age or health classification. It is concluded that nitrous oxide-oxygen sedation is an excellent and safe aid to dental care.

Caries prevalence and distribution in 3-20-year-olds in Jönköping, Sweden, in 1973, 1978, 1983, and 1993.

Four cross-sectional studies were carried out in 1973, 1978, 1983, and 1993 to collect clinical and radiographic epidemiological data on the dental health status of the inhabitants of Jönköping, Sweden. The aim of the present paper was to use these data to analyze trends in the development of caries among children and adolescents between 1973 and 1993. Approximately 500 randomly selected individuals evenly distributed among the age groups 3, 5, 10, 15, and 20 years participated in each study. The main results show that the numbers of caries-free individuals increased in all age groups. In 1993, the mean number of decayed and filled tooth surfaces in the primary (dfs) and the permanent (DFS) dentition in all age groups was less than half of that found in 1973. Most of this decrease took place during the first 5 years, i.e., between 1973 and 1978. Between 1978 and 1983, only minor changes were observed. There was a further reduction of approximately 30%-50% in dfs/DFS between 1983 and 1993 in 3-, 5-, 10-, and 20-year-olds. The frequency distributions of dfs/DFS for 5- and 15-year-olds revealed an increasing skewness over time: in 1993, a large majority of the children and adolescents had a low or moderate caries severity while only a small group had high scores of dfs/DFS.

Epidemiologic study of idiopathic enamel hypomineralization in permanent teeth of Swedish children.

In the late seventies an increasing number of children showing extensive and severe idiopathic hypomineralization of the enamel of incisors and permanent first molars was reported within the Public Dental Services in Sweden. An epidemiologic study was initiated to analyze the prevalence, extension and severity in Swedish children born in 1970 and in the years before and after. 2252 children born in 1966-74 were examined according to well defined criteria on enamel hypomineralization. It was found that 15.4% of the children born in 1970 showed such changes. The corresponding figures for children born in 1966, 1969, 1971, 1972 and 1974 were 6.3, 7.3, 7.1, 5.2 and 4.4, respectively.

Osseointegrated implants in the oral habilitation of a boy with ectodermal dysplasia: a case report.

The most characteristic oral feature in ectodermal dysplasia is hypodontia. Children and adolescents suffering from ectodermal dysplasia often need extensive and complicated prosthetic treatment. The development of techniques for osseointegrated implants offers new possibilities for the oral habilitation of these children. This paper describes the oral habilitation of a boy with severe ectodermal dysplasia and where Brånemark osseointegrated implants have been used as part of the treatment. The patient was seen at the dental department at the age of 1.5 years. Two conically-shaped upper incisors were at that time the only teeth that had erupted. The treatment was planned in a multidisciplinary odontological group involving paediatric dentistry, orthodontics, prosthodontics, oral surgery and maxillofacial radiology. At the age of 3 years it was verified that the boy had four primary teeth (53, 51, 61, 63) and four permanent teeth (16, 11, 21, 26). There were no teeth in the lower jaw. The alveolar ridges in the edentulous areas were low or missing. During the period 3-6 years of age the boy used an upper partial denture adapted to allow the mesial drift of the 16 and 26 teeth. At the age of 6 years, two Brånemark implants were inserted in the lower front-cuspid region. A specially designed overdenture for the lower jaw was constructed. The overdenture was retained in contact with the male attachments by two cuffs of heat-polymerized resilient silicone. Over the next 4 years the dentures were modified due to the eruption of permanent teeth and growth. However, only minor corrections were necessary concerning the retention system of the lower denture. The implants are well osseointegrated and stable and allow the boy to use a lower denture without any complications.

Nitrous oxide scavenging in dental surgery. I. A comparison of the efficiency of different scavenging devices.

Chronic exposure of dental personnel to trace concentrations of nitrous oxide has been reported to constitute a health hazard. During the dental treatment under nitrous oxide-oxygen sedation dentists are frequently exposed to as much as 1000 ppm of nitrous oxide. Nitrous oxide-oxygen sedation equipment with scavenging devices for removal of expired and excess gases is available. The aim of this study was to determine the efficiency of different scavenging devices by means of a standardised experimental model and thereby study occupational nitrous oxide exposure in dental surgery. Seven commercially available breathing systems were studied. The experimental model of measuring occupational nitrous oxide exposure during a 25-minute standardised dental treatment showed high reproducibility and might be useful for determining whether or not a system has a reasonable chance of meeting the requirements set by different national boards of occupational safety and health. The scavenging efficiency of the different systems tested varied. According to this method of evaluation, five out of seven systems might have good possibilities of meeting Swedish standards of occupational exposure (nitrous oxide limit value 100 ppm).

Nitrous oxide scavenging in dental surgery. II. An evaluation of a local exhaust system.

A deleterious effect on physical and mental health of chronic exposure to trace concentrations of nitrous oxide has been reported. Despite careful handling and sedation technique, gas-tight equipment and breathing circuits, a non-recirculation ventilation system and efficient expired and excess gas scavenging equipment, high local nitrous oxide concentrations may occur e.g. with the use of poorly fitting nose masks and/or the administration of nitrous oxide to uncooperative patients. Local exhaust systems have proved valuable in such situations. The aim of this study was to determine the optimal location of a local exhaust system in relation to leakage in an experimental situation with high local nitrous oxide contamination in a dental surgery and to establish the necessary evacuation capacity of such a local exhaust system. Four different evacuation capacities, 140, 200, 260 and 300m3/h, and three different distances from the patient to the nozzle of the local exhaust system, 10, 20, 30 cm, were tested. With the local exhaust system used in this study, an optimal capacity of about 200 m3/h and a position 20 cm or less in front of the patient seem to meet requirements of occupational exposure to nitrous oxide set by national boards of safety and health.

Physical properties of nitrous oxide-oxygen sedation equipment used in dentistry.

The breathing circuits in eight types of commercially available nitrous oxide-oxygen sedation equipment, with and without gas scavenging devices in operation, were tested with respect to resistance to breathing, carbon dioxide retention and the dilution of the administered gas by fresh air drawn into the circuit. The equipment was designed for use in dentistry. Several of the systems had one or more of the following drawbacks: high resistance to high gas flow, carbon dioxide retention or dilution of the gas mixture by air, the functions being affected by the scavenging equipment. Only one modified circuit showed a high standard of performance in these respects.

Caries prevalence and distribution in individuals aged 3-20 years in Jönköping, Sweden, 1973, 1978 and 1983.

In 1973, 1978, and 1983 epidemiological studies on dental health were performed in the community of Jönköping, Sweden. Each investigation covered about 500 individuals evenly distributed in the age groups 3, 5, 10, 15 and 20 years. The subjects were examined clinically and radiographically. In the present study, caries prevalence and distribution are analysed too. The total number of DFS decreased by about 50 per cent between 1973 and 1983 in all age groups. Most of the changes occurred during the period 1973-1978. The largest percentage reduction in DFS had occurred on the buccal/lingual surfaces. The number of FS-proximal showed a decrease in 1983 compared to 1973, while the number of DS-proximal was almost unchanged during the period. A closer analysis of DS-proximal revealed that there was an increase in the proportion of lesions restricted to the enamel between 1973 and 1983. In the 3 and 5-year-olds, 29 and 32 per cent of the carious lesions were restricted to the enamel in 1973 compared to 58 and 53 per cent, respectively, in 1983. For the groups of 10, 15 and 20 year-olds the numbers were 84, 84 and 78 per cent respectively in 1973, and 89, 90 and 86 per cent in 1983. A change in distribution of individuals according to DFS was found in 1978 compared to 1973. This change was still more pronounced in 1983, most of the subjects showing a low number of DFS. The results of the study show that when caries prevalence is decreasing more refined diagnostic measures should be used in order to make it possible to follow changes.(ABSTRACT TRUNCATED AT 250 WORDS)

Dental caries in one- and two-year-old children living in Sweden. Part I--A longitudinal study.

There are few epidemiological studies on caries prevalence in young children. The aim of this study was to describe the caries prevalence in 1- and 2-year-old children. All 1-year-old children, living within the area of four child welfare centres, were invited to participate. 632 children out of 671 invited were examined for dental caries. Among the children examined 120 (19%) were immigrants. One year later 326 of the 632 previous examined children were selected for a second examination of dental caries. Fifty-four children (18.1%) were immigrants. At the age of one and two years 0.5 and 7.7 per cent respectively of the children had caries. In 2-year-old children with caries the mean number of decayed tooth surfaces was 6.3. About fifty-two per cent of this group of children were immigrants. In 2-year-old immigrants 22.2 per cent had caries compared to 4.5 per cent in non-immigrant children (p less than 0.001). This study shows that, as early as at one and two year of age, a group of children have developed a number of carious lesions. Further studies in infants on predisposing factors related to early caries activity are urgent in order to find measures for effective preventive care.

Oral health in pre-school children living in Sweden. Part III--A longitudinal study. Risk analyses based on caries prevalence at 3 years of age and immigrant status.

A decreasing proportion of children require operative treatment each year and an increasing proportion of children will at recall require no operative care. This would provide resources to give individualised prevention to children at risk for developing new carious lesions. From 3 years of age, however, the prevalence of caries increases up to the age when the primary dentition exfoliates, even though the children attend regular dental service programmes yearly, and for some children dental caries remains a significant problem. The purpose of the present study was to describe the dental health of a group of 6-year-old children living in Sweden, with special reference to caries prevalence at 3 years of age and to immigrant status. At 6 years of age, 45% of the children were free of initial and manifest carious lesions in the primary cuspids and molars. The mean caries increment between 3 and 6 years was 0.9 tooth surfaces for children who were caries free at 3 years of age compared to 4.5 tooth surfaces for children with manifest carious lesions at the same age. The mean caries increment from 3 to 6 years was 1.3 in the non-immigrant group and 3.6 in the immigrant group. For the majority of the children in this study, current preventive dental care seems sufficient. However, for about one-third of the children (children with carious lesions at 3 years of age and/or immigrant status), current caries preventive programme used in the Public Dental Service are inadequate.