Showing papers by "University of Gothenburg published in 1978"

Effect of controlled oral hygiene procedures on caries and periodontal disease in adults

Abstract: The present report describes the result of a clinical trial in which a group of adults have been maintained on a proper oral hygiene standard over a 6-year period. In 1971–72, 375 individuals were recruited to a test group and 180 to a control group. During the 6 years of trial, 65 persons from the test group and 34 controls were lost. The patients were divided into three age groups; I 50 years. The members of the test and control groups were first subjected to a Baseline examination which included assessments of oral hygiene, gingivitis, periodontal disease and caries. Following this examination all caries lesions were treated and ill-fitting dental restorations adjusted. Each patient was also given a detailed case presentation and a dental prophylaxis. The control group patients were not involved in any further dental health programs during the subsequent 6-year period. Once a year, however, they were recalled to a public dental health clinic for examination and received symptomatic dental treatment. The test group participants, on the other hand, were given a preventive treatment, repeated once every 2–3 months which included (1) instruction and practice in oral hygiene techniques and (2) meticulous prophylaxis. The patients were re-examined 3 and 6 years after the baseline examination. At the Follow-up examinations the parameters studied at the Baseline examination were recorded again. The findings demonstrated that a preventive program which stimulates individuals to adopt proper oral hygiene habits may resolve gingivitis and prevent progression of periodontal disease and caries. Traditional dental care, on the other hand, did not prevent the progression of caries and periodontitis in adults.

Designing semi-confusing information systems for organizations in changing environments

Abstract: Organizations have many stabilizers but quite often lack proper destabilizers. They establish fixed repertoires of behavior programs over time, and many grow too rigid and insensitive to environmental changes. Drifting into changing environments, they react with delayed and improper responses.

Standardization of allergen extracts with appropriate methods. The combined use of skin prick testing and radio-allergosorbent tests.

Abstract: This paper presents recommendations for standardization of allergen extract by the combined use of skin prick tests and radioallergosorbent tests. These tests provide appropriate means for quantitation of the total allergenic activity of an extract. Advantages and limitations are discussed with reference to the literature.

Intrafamilial levels of Streptococcus mutans and some aspects of the bacterial transmission.

Abstract: — The number of S. mutans (S.m.) in saliva of parents and their children was studied. Thirty-six children, 4 1/2–5 years old, and their parents participated. A quantitative correlation was found between the number of S.m. in the mothers and their children. The degree of infection also seemed to reflect the caries experience of the child. When adults with different levels of S.m. in saliva contaminated metal spoons with saliva, a correlation between the salivary count of S.m. and the number of microorganisms transferred to the spoon was found. The survival of S.m. on saliva-contaminated test-plates was tested. After 7 h the number of viable S.m. had decreased considerably but a few cells could be found after 24–48 h. To study the presence of S.m. on objects in the city often touched by hands, MSB-containing agar dishes were pressed against several objects such as doorhandles. Only four out of 24 objects were found to be contaminated by S.m.

Food sensitivity reported by patients with asthma and hay fever. A relationship between food sensitivity and birch pollen-allergy and between food sensitivity and acetylsalicylic acid intolerance.

Abstract: Among adult patients with bronchial asthma and/or allergic rhinitis undergoing allergological investigation with skin test, nasal provocation test and RAST, 1129 answered a questionaire regarding food sensitivity (FS). 276 (24%) of the patients reported some kind of allergic symptoms on eating or handling various foods, of which hazel nut, apple and shell fish were the most often named. Females reported FS more often than males. A correlation was found between birch pollen allergy and FS with nuts, apple, peach, cherry, pear, plum, carrot and new potato. The higher the degree of birch pollen allergy, according to skin test, RAST or provocation test, the higher the frequency of FS. A correlation was found too between acetylsalicylic acid intolerance and FS with some foods, e.g. nuts, strawberry, almond, green pepper, hip, chocolate, egg, cabbage, milk and wine. The connection between birch pollen allergy and FS is probably explained by the structural relationship between birch pollen allergen and some allergens of the foodstuffs, whereas the high incidence of FS in acetylsalicylic acid-intolerant patients is probably explained by additives in foods as well as salicylates or benzoates naturally occurring in some food.

Humidifier fever and endotoxin exposure

Abstract: Three cases of humidifier fever were detected in an office environment. Flavobacteria were found in the contaminated water in a humidifier. After an experimental exposure, the three persons with previous symptoms suffered from fever and slight respiratory symptoms. A leucocytosis and an increase in the number of segmented white blood cells were found the day following the exposure. General immunoglobulins as well as antibodies to Flavobacterium and endotoxin were slightly elevated in the exposed group. The possibility that endotoxins may be the causative agent by means of an indirect complement activation is discussed.

Effect of experimentally induced marginal periodontitis and periodontal scaling on the dental pulp.

Abstract: Experimental breakdown of the periodontal attachment apparatus was produced in six young adult monkeys to study the effect on the tissue of the dental pulp by (1) periodontitis, (2) scaling and plaque accumulation on exposed root dentin. Periodontal tissue breakdown was induced by the placement of ligatures around the neck of 92 permanent teeth. Subsequent plaque formation caused marked loss of periodontal tissue support, which after a period of 5--7 months amounted to 30--40% of the root length. One group of teeth received no further treatment. Other teeth were subjected to scaling and root planing. Following treatment, plaque was allowed to accumulate for 2, 10, and 30 days on the freshly planed root dentin surfaces. Histologic examination revealed that in comparison to teeth with normal periodontal conditions, 57% of the teeth exposed to periodontitis exhibited pathologic pulp tissue alterations. Secondary dentin formation and/or inflammatory cell infiltrates were observed within localized areas of the pulp subjacent to root surfaces exposed to periodontal tissue destruction. The changes within the pulp were of "mild" nature and only one tooth displayed signs of total pulp necrosis. Lateral canals communicating with both the pulp cavity and the exposed root surface were never detected. Teeth subjected to scaling and subsequent plaque accumulation in comparison with teeth with periodontitis alone exhibited no obvious aggravation or increased incidence of pathologic pulp reactions. The findings show that in the monkey (1) periodontal destruction limited to the cervical half of the root and (2) plaque accumulation on exposed root dentin does not cause severe alteration in the pulp of the roots involved.

Contamination of toothpaste and toothbrush by Streptococcus mutans.

Abstract: Toothbrushes and toothpaste tubes used by persons infected with S. mutans were examined for the presence of this microorganism. Fifteen minutes after brushing greater than 10(6) S. mutans were isolated from the toothbrushes and after ordinary storage for 24 h 10(4) were recovered. From two out of 10 toothpaste tubes S. mutans was isolated from the orifice of the tube. The implications of these findings for the spread of the microorganism are discussed.

Microcirculation in Grafted Bone:A Chamber Technique for Vital Microscopy of Rabbit Bone Transplants

Abstract: A method enabling in vivo observations of the microcirculation in orthotopically transplated bone in the rabbit is presented. The technique permits repeated study of a well-defined bone tissue compartment both before and after grafting to an autogenous or allogenous recipient site, respectively. It yields information about the reorganization of the microvascular system and the resorptive and formative processes of bone remodelling during incorporation of grafted bone. In the autologous experimental series, new capillaries were seen in the bone grafts 4 to 5 days after transplantation. No re-utilization of pre-existing graft vessels was observed.

Determination of glomerular filtration rate in advanced renal insufficiency.

Abstract: The glomerular filtration rate (GFR) has been determined in 17 patients with advanced renal insufficiency (GFR<15 ml/min) by different clearance techniques using creatinine, inulin and 51Cr-EDTA as filtration markers. With renal inulin clearance as reference method for GFR, endogenous renal creatinine clearance overestimated GFR by an average of 30%. Renal clearance of 51Cr-EDTA and inulin were closely correlated and thus 51Cr-EDTA is a suitable GFR marker even at low filtration rates. However, it was found that the plasma clearance of 51Cr-EDTA overestimated the GFR often by more than 100% in the range 2.6-11.2 ml/min. Renal clearance measured during 24 h was lower than 4 h renal clearance with the patient well hydrated and resting in bed. It is concluded that the precise measurement of low glomerular filtration rates requires the use of renal clearance techniques. Four-hour 51Cr-EDTA renal clearance is a suitable method for measuring and following the development of renal function in advanced renal insu...

The effect of progressive tooth mobility on destructive periodontitis in the dog

Abstract: . The aim of the present study was to assess the influence of traumatic forces causing a gradually increasing tooth mobility on an ongoing destructive periodontitis. The experiments were performed in five dogs fed a diet which permitted dental plaque accumulation. Periodontal breakdown was induced around the mandibular third and fourth premolars (4P, 3P and P3, P4) by the placement of plaque retention ligatures around the neck of the teeth. After 330 days, when approximally 50 % of the supporting tissues had been lost, mucoperiosteal flaps were raised around the four premolars and notches prepared in the buccal root surfaces at the marginal termination of the alveolar bone. The notches served as landmarks for measurements to be made in histological sections. The flaps were resutured and new plaque retention ligatures placed around the roots of all four teeth. One week later (Day 0), P3 and P4 (test teeth) were subjected to jiggling forces in a bucco-lingual direction with the use of an elevator. The jiggling procedure which had a duration of 30 seconds, was repeated on Days 4, 8, 12 and 16, and was guided in such a way that the tooth mobility gradually increased during the experimental period. The animals were sacrificed on Day 26, and sections of 4P,3P and P3, P4 were prepared for light microscopic examination. The results of the study demonstrated that jiggling forces, resulting in a progressive increase of tooth mobility, mediated an enhanced rate of destruction of the supporting apparatus in dogs with an ongoing process of periodontal tissue breakdown.

Prevalence and awareness of malocclusion in Swedish men.

Abstract: Previous orthodontic treatment, the awareness of malocclusion, the demand for orthodontic treatment and the prevalence of malocclusion were studied in 389 Swedish men, aged 21–54 years (mean age 32 years). Nine percent had been treated with an orthodontic appliance and 15% reported that permanent teeth had been extracted on orthodontic indications. Malposition of teeth was found in 75 %, with rotation as the most common type of malposition. Crowding was recorded in 43 % and spacing in 18%. Fifty-seven percent had some occlusal anomaly. The need for orthodontic treatment was rated on a four-point scale. It. was found that 76% were in need of treatment. The need for treatment was only slight in half of the men but moderate to urgent in 25% of the sample. About a quarter of the men were aware of malposition of front teeth, equally often for maxillary and mandibular teeth, but only about 1 % were aware of malposition of posterior teeth. Only a few percent thought they were in need of orthodontic treatment. The presence of malocclusion was correlated to age, place of birth and educational level. This might perhaps be a consequence of tooth loss.

Effect of caries-preventive measures in children with high numbers of S. mutans and lactobacilli

Abstract: — On the basis of the number of Streptococcus mutans and lactobacilli, 645 children 9–12 years old were divided into five groups. The children with the highest number of S. mutans and lactobacilli were considered to be at a high caries risk and were divided into three groups with 49 children in each. One group received preventive measures from a specially trained nurse twice a month, one group was treated once a month and the third group served as a control. The other 498 children with lower numbers of S. mutans and lactobacilli were considered to be at a lower caries risk and were divided into two groups. One group was treated once a month while the other was a control. The children with originally high numbers ofS. mutans and lactobacilli developed significantly more new carious lesions after 1 and 2 years (2.5 and 4.3) than the children with low counts in the control groups (1.9 and 2.8). All the children in the test groups which had received the preventive program developed significantly less caries than the corresponding control group. In the test risk group treated twice a month the caries activity was extremely low during the 1st year with an average of 0.34 new carious lesions. After 2 years the average was 0.92. The microbial conditions as well as the saliva secretion rate, buffer capacity and saliva pH did not seem to be influenced by the preventive program.

Cleavage of Epstein-Barr virus DNA by restriction endonucleases EcoRI, HindIII and BamI.

Abstract: The cleavage of the DNAs of the B95-8 and P3HR-1 virus strains of Epstein-Barr virus by the restriction endonucleases EcoRI, HindIII and BamI was investigated using a new technique for quantitative evaluation of the fluorescence of ethidium stained DNA fragments separated on agarose gels. The results obtained with B95-8 DNA showed that in addition to the limited repetitions of nucleotide sequences observed in the EcoRI and HindIII cleavage patterns, the molecule contained a BamI fragment with a molecular mass of 2.0 megadaltons which was present in a total of about 11 copies and localized to a limited part of the DNA molecule. The same sequences were also present in the P3HR-1 DNA albeit in a lower molar ratio. P3HR-1 DNA yielded restriction enzyme cleavage patterns suggesting DNA sequence heterogeneity of P3HR-1 virus. No fragment was present in more than about 4 copies per molecule of P3HR-1 DNA. Comparison of the restriction enzyme cleavage patterns of P3HR-1 and B95-8 DNA revealed a high degree of structural homology emphasized by nucleic acid hybridization experiments with EBV complementary RNA synthesized in vitro.

Application of the ELISA for Determination of Immunoglobulin Class‐specific Escherichia coli Antibodies

Abstract: Antibodies of different immunoglobulin classes possess various biological activities. Often, these are not closely related to their serological titres, determined by various techniques [l]. The reason for this discrepancy is that serological methods mostly favour antibodies of one or the other immunoglobulin class [2]. An immunological assay which reflects correctly the amounts or activities of the antibodies of the different immunoglobulin classes would be advantageous. The enzyme-linked immunosorbent assay (ELISA) is a technique with possibilities for correctly recording the capacity of antibodies to bind to a solid-phase-coupled antigen irrespective of the immunoglobulin class [l, 141. We have used the ELISA to quantitate antibodies of the different immunoglobulin classes, including antibodies carrying secretory component (SC) specific for various Escherichia coli antigens. During this work we attempted to elucidate the relation between the presence and amount of specific antibodies and their protective capacity during infections. The ELISA titres expressed in different ways were compared with the antibody titres determined with other serological techniques often used for serological diagnosis and in research. These tests included the indirect haemagglutination (IHA) method [22], the indirect haemolysis (IHL) method [22], and the ammonium sulphate precipitation (ASP) technique [7]. This communication describes some of our experiences with the ELISA for quantitation of antibodies in connection with exposure to E. coli antigens in patients and in experimental animals.

Clinical and structural alterations characterizing healing gingiva.

Abstract: The aim of the present study was to compare the structural composition of the gingiva of dogs which had not previously suffered from inflammation with that of gingiva which for 6 months had been inflamed, but subsequently healed. The experiments were carried out in eight dogs. After weaning, the dogs were daily subjected to tooth cleaning. When the animals were 10 months old a clinical examination was carried out after which the dogs were randomly distributed into two groups, A and B. Immediately after the clinical assessments, gingival biopsies were obtained from the premolars and molars of the dogsof Group A. The dogs of Group B were allowed to accumulate plaque during a 6-month period after which the examinations were repeated and biopsies were sampled from predetermined areas of the dentition. Following biopsy the remaining teeth of the dogs of Group B were scaled. During the subsequent 6 weeks, the animals were daily subjected to tooth cleaning. The examinations were repeated and biopsies sampled on days 4, 7, 14, 21, 28 and 42. The biopsy material was subjected to morphometric analysis. The resuls showed that it is possible to shift a chronically inflamed gingiva into one which, from a clinical and structural point of view, is almost identical to a gingiva which has never been exposed to gross plaque accumulation. This shift was achieved by elimination of calculus and plaque and by the institution of a careful, daily practiced plaque control program. During healing, the inflammatory cell infiltrate in the connective tissue below the junctional epithelium gradually disappeared and became replaced by collagen. In comparison to inflamed gingiva during healing, the leukocyte content of the junctional epithelium was reduced, whle ee peg formations remained. In the connective tissue papillae beneath these rete pegs, vessels could be recognized. This gave the connective tissue of the healed gingiva a higher vascular content thatn that of a gingiva which had not previously suffered from inflammation.

Linalool in mandibular gland secretion ofColletes bees (Hymenoptera: Apoidea)

Abstract: Uinalool was identified as the main component of the mandibular gland secretion in females and males of four species ofColletes bees, viz.,C. cunicularius, C. daviesanus, C. impunctatus andC. succinctus. It was also shown to be the dominant volatile compound in the same gland in maleC. floralis (the female of this species has not yet been investigated). Further, in another species,C. similis, linalool is present in the mandibular gland secretions of females and males, but the dominant volatile component in these secretions is geranial, together with neral. Females of the speciesC. fodiens seem to lack monoterpenes altogether; nonadecane is the dominant volatile compound of the cephalic secretion (based on analysis of a single individual). When linalool is put out in the area of nest aggregation ofC. cunicularius, where the males are “patrolling”, a distinct increase in flight activity is noted. The function of linalool is discussed on the basis of field observations.

Effect of a field program based on systematic plaque control on caries and gingivitis in schoolchildren after 3 years.

Abstract: The effect of a field program, based on systematic plaque control, on caries and gingivitis was tested during a 3-ycar period on 1,100 schoolchildren. Once every 3rd week the children were given oral hygiene instructions, professional toothcleaning and fluorides topically delivered by specially trained dental nurses. The children of a control group of approximately the same number of pupils, participated in a preventive program consisting of mouthrinsings once every 2nd week with a 0.2% sodium fluoride solution. The children of the third and fourth grades were, at the start of the experiment, selected as reference groups and then continuously examined once every year. At the end of the trial the mean reduction of surfaces harboring plaque and units with gingival inflammation was 59% and 73%, respectively. The reduction in caries increment was 51%.

L-tryptophan and 5-hydroxytryptophan in the treatment of depression. A review.

Abstract: Trials performed do not provide evidence for an antidepressant effect of 5-HTP. L-TP, without interacting pharmaca, does not appear to be a well-documented antidepressant. The only convincing evidence for L-TP as an antidepressant is that L-TP enhances the effect of MAOI.