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Biomedical subjects

L Helldén

Publications and source records attributed to L Helldén.

At least 19 recordsLinked to original sources
PubMed1992

Need and demand for orthodontic treatment in an adult Swedish population.

The prevalence of malocclusion, the need for and the demand for orthodontic treatment was studied in a randomly selected adult Swedish population > or = 20 years of age. Nine-hundred-and-twenty subjects were examined of whom 669 had their own teeth in occlusion. From those a group of 157 subjects was selected on the basis of objective need and/or subjective demand for orthodontic treatment. The various regimens of treatment required in this group were investigated. The prevalence of malocclusion ranged from 17 to 53 per cent in the various age groups. The spectrum of malocclusion was similar to that previously reported in Swedish children. The awareness of their malocclusion was higher among younger than older subjects and among those who had severe malocclusion. Objective treatment need, evaluated by two experienced orthodontists, was estimated at 11 per cent of the total population, whilst orthodontic treatment was requested by approximately 5 per cent of the population studied.

Adult↗
PubMed1990

Occurrence of oral mucosal lesions, the influence of tobacco habits and an estimate of treatment time in an adult Swedish population.

A randomly selected sample of adult subjects living in a Swedish county was examined for the presence of oral mucosal lesions. Nine hundred twenty (920, 95%) of the selected sample of 967 subjects, comprising approximately 0.75% of the total adult population, were examined; lesions were registered in 596 of the 920. The registered prevalence levels were very similar to earlier reported data from Sweden. Further, the relationship between tobacco habits and mucosal lesions was analyzed and the time needed for treatment of the lesions was estimated. A positive correlation could be demonstrated between tobacco use and leukoplakia, frictional white lesion, coated tongue, hairy tongue and excessive melanin pigmentation, while a negative correlation was observed for geographic tongue and aphthous ulcers. Approximately 70% of the lesions were associated with local irritants (e.g. dentures, tobacco, cheek and lip biting etc.). The estimated mean time required for registration and management of oral mucosal lesions in the studied group of adults was 24 min per individual.

Adult↗
PubMed1990

Prevalence of previous endodontic treatment, technical standard and occurrence of periapical lesions in a randomly selected adult, general population.

A random sample of 967 subjects selected from the total population in a Swedish county were examined radiographically regarding prevalence and quality of endodontic treatment and occurrence of periapical lesions. The relationship between the technical standard of endodontic treatment and the occurrence of periapical lesions was also analyzed. Of the selected individuals, 95% attended examination (751 dentate and 169 edentulous individuals). Of the 17,430 teeth examined, 1,492 (8.6%) were endodontically treated. Approximately 70% of the treated root canals were inadequately obturated; 10% showed excess of root filling beyond the apex. The prevalence of periapical lesions was 2.9%, and 24.5% of the endodontically treated roots demonstrated periapical lesions. Root fillings ending more than 2 mm from apex had a significantly lower frequency of periapical lesions than root fillings ending within 2 mm of the apex. No difference in the frequency of periapical lesions was found between properly and improperly obturated root canals. Excess of root filling material beyond the apex was related to a significantly higher frequency of periapical lesions.

Adult↗
PubMed1990

Mutans streptococci, oral hygiene, and caries in an adult Swedish population.

The objective of the present study was to describe the distribution of salivary mutans streptococci in a randomly selected adult population and to relate the distribution to the prevalence of caries. The aim was also to study the association between caries and different levels of oral hygiene (OH). The results were based on the assessment of caries, dental plaque, and concentration of salivary mutans streptococci in 914 subjects who represented 95% of an age- and gender-stratified population sample of 967 individuals, randomly selected from the total adult population living in Alvsborg County, Sweden. The results showed that the distribution of mutans streptococci among dentate adults not wearing any kind of removable denture(s) was similar to that previously reported from studies on Swedish schoolchildren, while a comparably higher proportion of subjects with high levels of mutans streptococci was found among the dentate individuals wearing some kind of removable denture(s). Even higher proportions were found among edentulous individuals with complete denture(s). There was a correlation between mutans streptococci concentration in saliva and caries. The subjects with lower concentrations showed a significantly lower mean number of decayed surfaces, compared with the individuals with higher concentrations of mutans streptococci in their saliva. The median OH standard was lower in the older age groups, and there was a higher ratio of decayed surfaces per remaining tooth in those age groups, in comparison with the younger groups. However, for individuals without mutans streptococci, no relation between OH standard and caries could be found and, regardless of OH standard, higher numbers of decayed surfaces were found with an increasing concentration of mutans streptococci in saliva.

Adult↗
PubMed1990

Prevalence of signs and symptoms of dysfunction in the masticatory system: an epidemiologic study in an adult Swedish population.

The prevalence of signs and symptoms of dysfunction in the masticatory system was studied by questionnaire and clinically in a randomly selected age- and sex-stratified sample of Swedish adults as a part of an epidemiologic survey on oral health. The prevalence of dental wear was also registered. There were 920 subjects examined, representing a participation rate of 95%. The questions and the clinical examination parameters were in accordance with those suggested by Helkimo in 1973. Reported symptoms decreased with age, while clinical signs increased. The prevalence of severe dysfunction was extremely low. The degree of dental wear increased with age, but extensive wear was extremely rare in women.

Adult↗
PubMed1989

Oral health status in an adult Swedish population. Prevalence of teeth, removable dentures and occlusal supporting zones.

The present study, which is part of a comprehensive cross-sectional epidemiologic survey on oral health among the adult population in a Swedish county, reports the results from the clinical assessment of remaining teeth, "occlusal supporting zones" (Eichner 1955), prevalence of edentulousness and removable dentures. The survey was carried out during 1983-1984. The adult population of 122,886 inhabitants was stratified according to age, sex and place of residence. From the different strata 0.75% (1.5% above 79 years) of the population was randomly selected to participate in the survey. Of the 967 selected individuals 920 (95.1%) attended full examination. The results showed a gradual reduction in the mean number of remaining teeth by age; somewhat faster after the age of 50 coincident with a significant increase in the prevalence of edentulousness. The prevalence of edentulousness and complete dentures was about twice as high among women as among men. In the dentate individuals the occlusal status was less favorable among men. This finding may explain the observed higher prevalence of removable partial dentures among the dentate men compared to the dentate women. An extrapolation between the results from the present study and results from previous studies in the Swedish population indicates that the oral health in the population below 50 years of age has improved during the last decade. This trend may predict that the observed improvement will follow the population, at present younger than 50 years, up through the ages.

Adult↗
PubMed1989

Oral health status in an adult Swedish population. Prevalence of caries. A cross-sectional epidemiological study in the Northern Alvsborg county.

The aim of the present epidemiological study was to describe prevalence, distribution and type of caries in an adult Swedish population. After stratification with respect to age (20-29, 30-39,.....greater than 79 years of age), sex and location of residence (city, village, rural region), a random sample of 967 individuals was drawn (0.75% of the total adult population greater than 19 years). The results were based on radiographic and clinical examination of 919 individuals, of whom 750 were dentate (participation rate: 95%). The examinations were carried out from November 1983 to December 1984. The caries registrations distinguished between enamel caries and root caries, subdivided into manifest and initial caries. Despite lower number of remaining teeth in older ages, the mean number of surfaces with manifest caries (DS) was relatively even in all age groups (4.1-5.1 DS), except for the youngest age group ("20-29 years": mean 3.1 DS). When the number of decayed teeth (DT) were expressed as a percentage of remaining teeth, the ratio (%) was markedly higher in the older age groups than in the younger age groups. Initial caries was more frequent in the younger age groups. In the age groups above forty years the majority of the observed carious lesions involved root surfaces. In the oldest age group ("greater than 79 years of age"), 95% of the lesions were root caries. The mean number of filled surfaces (FS) was higher among women than men, while untreated caries (DS) showed a tendency of higher values for men. No significant differences in caries prevalence related to location of residence could be demonstrated.

Adult↗
PubMed1988

A computerized system to measure interproximal alveolar bone levels in epidemiologic, radiographic investigations. II. Intra- and inter-examiner variation study.

The study was aimed at analyzing intra- and inter-examiner variations in computerized measurement and in non-measurability of alveolar bone level in a cross-sectional, epidemiologic material. At each interproximal tooth surface, alveolar bone height in percentage of root length (B/R) and tooth length (B/T) were determined twice by one examiner and once by a second examiner from x5-magnified periapical radiographs. The overall intra- and inter-examiner variations in measurement were 2.85% and 3.84% of root length and 1.97% and 2.82% of tooth length, respectively. The variations were different for different tooth groups and for different degrees of severity of marginal periodontitis. The overall proportions of non-measurable tooth surfaces varied with examiner from 32% to 39% and from 43% to 48% of the available interproximal tooth surfaces for B/R and B/T, respectively. With regard to the level of reliability, the computerized method reported is appropriate to cross-sectional, epidemiologic investigations from radiographs.

Adult↗
PubMed1982

Pulpal effects of electrosurgery involving based and unbased cervical amalgam restorations.

The pulpal effects of electrosurgery involving unrestored enamel, cementum, calcium hydroxide-copal varnish-based restorations and unbased restorations were evaluated in extracted human teeth and posterior teeth of cynomolgus monkeys. Electrosurgery for all studies was performed with a fully rectified filtered unit under conditions of normal clinical usage. Studies in extracted human teeth measured the voltage potential generated between a reference probe in apical pulp tissue and an activated electrosurgery electrode placed on enamel, cementum, based restorations, and unbased restorations. Placement of a base reduced but did not prevent passage of electrosurgical current, and no measurable potential was associated with activated electrode contact on cementum or enamel. Studies in three cynomolgus monkeys included electrosurgery of based and unbased cervical silver amalgam restorations, electrosurgery of unrestored enamel, restored teeth not subjected to electrosurgery and teeth that were neither restored nor subjected to electrosurgery. Electrosurgery of restored teeth, regardless of the presence of a base, consistently resulted in pulpal damage characterized by an altered dentin matrix, necrosis adjacent to the cavity preparation, and a transition zone between necrotic and apparently vital pulp tissue. By 8 weeks following electrosurgery, the majority of specimens showed replacement of the odontoblastic layer and adjacent pulp tissue by dense connective tissue with areas of irregular calcification.

Animals↗
PubMed1982

Response of the periodontal tissues of the beagle dog to polytetrafluorethylene implants.

The healing response of the periodontal tissues to polytetrafluorethylene was examined in the beagle dog. At midroot level, by way of a mucosal incision and a surgically created fenestration in the facial alveolar bone, a cylinder of polytetrafluorethylene 2 mm. in diameter was fitted tightly into a cavity preparation and cut even with the root surface. Histologic observations were made after 57 and 91 days of healing. In sites with optimal healing (minimal or no inflammation present) a thin layer of connective tissue with capillaries had proliferated into the narrow space between the implant and the cavity walls, and new cementum had formed on the walls and floors of the preparations. Bone replacement occurred in the peripheral parts of the fenestrations and in several instances a complete or nearly complete covering of bone had developed at the outer surface of the implant as well. Osseous tissue often contacted the polymer. Inflammatory infiltrate, concentrated at the cavosurface angles, was observed in sites with the poorest healing. This was associated with microscopic pulpal exposure and/or irritants in the interface between the polymer and the cavity walls. The implant material per se did not appear to produce an inflammatory response or impede the development of cementum and bone. Observations confirm the inertness of polytetrafluorethylene and suggest its use as a covering for reimplanted teeth.

Alveolar Process↗
PubMed1981

Clinical study to compare the effect of stannous fluoride and chlorhexidine mouthrinses on plaque formation.

A clinical study was conducted on four adults to compare the relative efficacy of 0.2% chlorhexidine digluconate and 0.1% stannous fluoride (SnF2). Using a crossover experimental design, subjects rinsed twice daily for 5 days with SnF2 and then, after a 2-day interim recovery period, for 5 days with chlorhexidine. Statistically significant differences (P less than 0.05) in the relative efficacy of the two agents were found. Chlorhexidine was more effective in reducing Gingival and Plaque Indices, plaque wet weight and bacterial Colony Forming Units, calculated both per subject and per group.

Chlorhexidine↗
PubMed1980

Effect of stannous fluoride mouthrinse on dental plaque formation.

A double-blind, crossover design study was performed on 29 young adults to test the effectiveness of 0.1% SnF2 mouthrinse (250 ppmF-) on plaque formation using clinical and microbiological criteria. Participants were assigned to either a placebo or SnF2 rinse which was used twice daily for 5 days. After an interim recovery period of 2 days, the participants used the alternate rinse in a similar manner for another 5 days. Clinical data collected at the end of each experimental period included Gingival Index (GI), and plaque scores. Supragingival plaque removed from each subject at the end of the experimental periods was weighed and then microbial enumeration was performed. Results showed that after SnF2 rinses, there were statistically significant reductions (P < 0.01) in plaque wet weight, number of bacteria per milligram plaque (CFU/mg), and total number of bacteria per sample (Total CFU). Visual plaque scores (PS) showed a significant (P < 0.05) but small reduction as a result of SnF2 rinse. No significant difference in gingival inflammation was noted. It is apparent from this study that, besides the well-documented ability of SnF2 to increase the resistance of teeth to demineralization, this agent is capable of reducing plaque formation. Long-term studies are indicated to examine usefulness of SnF2 in the control of early periodontal disease.

Adult↗
PubMed1977

Effect of topically applied neutrophil leukocyte extract on normal gingiva of dogs.

Seven beagle dogs were used to study the gingivitis-inducing potenial of a topically applied neutrophil leukocyte extract and to compare the vascular and cellular reactions with those induced by plaque extract applied in an identical manner. In four dogs neutrophil extract was applied onto the marginal gingiva in one jaw quadrant while Gey's medium was applied to the contralateral gingival units. In the remaining three dogs plaque extract and Gey's medium, respectively, were applied in the same way. After 6.5 h of topical application colloidal carbon (1 ml/kg bodyweight) was injected into a leg vein and after a further 1.5 h biopsies were obtained from the experimental regions. The results show that topical application of an extract from neutrophils induces both an increase in the number of crevicular leukocytes and an enhanced vascular permeability. As in previous studies plaque extract was found to promote the emigration of leukocytes and to alter the permeability of the dentogingival vessels. The vascular and cellular reactions were, however, more pronounced after application of plaque extract than after neutrophil extract.

Administration, Topical↗