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Biomedical subjects

M Knuuttila

Publications and source records attributed to M Knuuttila.

At least 55 records · Page 3Linked to original sources
PubMed1984

Corticosteroid therapy and periodontal disease.

In the present investigation, the frequency and severity of periodontal disease was assessed in a group of patients with multiple sclerosis receiving corticosteroid hormone therapy for neurological disease. Age-matched patients with multiple sclerosis but without hormone therapy as well as healthy subjects served as controls. Individuals suffering from multiple sclerosis or polyneuropathies were selected from a pool of patients who were under treatment at the Department of Neurology, The Central Hospital of Kuopio, Finland. 27 individuals were identified who had received more than 1.5 g prednisone over a 1-4 year period. The average amount of steroid given to these patients was 3.5 g. 26 individuals also suffering from neurologic disease had received no or only negligable amounts of hormone therapy and were used as diseased controls. Another control group comprised age- and sex-matched healthy individuals from the city of Kuopio. The dental examination which was performed by one dentist comprised assessments of the following parameters: oral hygiene status, gingival conditions, probing depth, gingival recession and height of the alveolar bone. The findings clearly demonstrated that patients with neurological disease who received corticosteroid therapy had the same frequency of gingivitis as non-treated diseased controls. Furthermore, data describing probing depth, gingival recession and height of the alveolar bone revealed that there was no difference regarding the frequency and severity of periodontal disease between the 2 groups of neurological diseased patients. It was concluded that corticosteroid therapy maintained over 1-4 years had no obvious influence on clinical parameters of periodontal disease in patients suffering from neurological disease.

Adolescent↗
PubMed1983

Fluoride content related to the elemental composition, mineral density and strength of bone in healthy and chronically diseased persons.

The fluoride (F) content of bone was determined and compared to the elemental composition, mineral density and compressive strength in bone specimens from the crista iliac of 88 subjects who had died suddenly, and from 50 subjects who had died as the result of chronic immobilizing diseases. The elemental composition of bone was determined using an atomic absorption spectrophotometer, mineral density using gamma-ray attenuation, compressive strength using a strain transducer, and F content using an ion-selective electrode. The increase of F content with age was not statistically significantly different between the groups. The Ca content of bone decreased more with age in post-menopausal women who had suffered from chronic diseases than in women who had died suddenly. The same was true for the negative correlation coefficient between Ca and F. A similar trend was found for mineral density. This does not support the idea that the F concentration obtained produces any effect that would clearly prevent bone loss in post-menopausal women when compared to those who had died suddenly. In both groups F content was correlated with Zn and Mn; in the sudden-death group Zn concentration explained 12.9% of the F concentration. The relation between Zn and F may be important in the formation and structure of biological apatite.

Adolescent↗
PubMed1983

Copper in human subgingival calculus.

The Cu concentration as well as the Ca, Mg, Fe, Pb, Zn, and F concentrations were determined in subgingival calculus and the relation of Cu to Zn, Ca, Mg and Fe described. Samples of human subgingival calculus of 60 pieces from 60 subjects were ashed in an acid solution and the cation concentrations were determined with atomic absorption spectrophotometry. The F content was analyzed with an ion-selective electrode. The data was analyzed using the multiple linear regression analysis. The mean +/-SD of the Cu concentration in the subgingival calculus was 48.4+/-59.0 micrograms/g. Four elements, Zn, Ca, Fe and Mg, explained 41.1% of the Cu content. Zn explained 25.5% and the correlation was positive, whereas Ca (10.4%) had a negative correlation with the Cu content. The results showed such a high Cu content that it could affect the mineralization of calculus.

Calcium↗
PubMed1982

Atomic absorption spectrometric evidence of relationships between some cationic elements in human dentine.

Dentine samples were prepared from 123 permanent teeth and Co, Cu, Mg, Mn, Ni, Pb, Sr and Zn concentrations were determined with an atomic absorption spectrophotometer. Relations between the cations were evaluated using the correlation matrix and multiple linear regression analysis. When the simultaneous variation of the concentrations of all determined elements was taken into consideration, the following statistically significant positive correlations were found: Cu-Mn, Mn-Co, Ni-Mn and Sr-Ni. A weaker correlation was obtained between Ni and Mg and between Ni and Pb. The only negative correlation was between Sr and Pb, but the explanation percentage in the regression model was low. The results indicated that the chemically and physically related elements Co, Cu, Mn and Ni formed positive correlations. Sr-Ni and Mn-Cu relationships were similar to those reported for human cancellous bone.

Adolescent↗
PubMed1982

Interaction between Li, Ni and Sr content in human cancellous bone.

Li, Sr and Ni content of human cancellous bone and their relation to elemental composition was studied in specimens obtained from 88 subjects with a normal mineral status and from 50 subjects having osteoporotic changes due to chronic immobilizing diseases. The concentrations of Ca, Mg, Cd, Co, Cu, Mn, Ni, Li, Pb, Sr and Zn were analyzed with an atomic absorption spectrophotometer and fluoride with an ion selective electrode. The data was analyzed with the linear multiple regression analysis. Ni had a statistically significant inverse relation to Li. There was a significant positive correlation between Sr and Ni contents. Chronic immobilizing diseases did not affect significantly Li, Sr and Ni contents. Also no age dependent changes of these elements were found. The mean concentration S.D. of Li was 0.23 +/- 0.14 microgram/g, of Sr 65.5 +/- 40.7 micrograms/g and Ni 1.29 +/- 0.83 micrograms/g, respectively. The strong interrelation between Li, Sr and Ni suggest that these elements should be analyzed together in studying the role of these elements in the mineralization.

Adolescent↗
PubMed1982

A 55Fe excited x-ray fluorescence method for the analysis of Ca content in enamel.

A 55Fe excited X-ray fluorescence method has been developed for the quantitative nondestructive analysis of Ca content in surface layers of teeth. To eliminate the effects due to curved enamel surface and the localisation of the tooth a special measuring geometry was constructed. The reproducibility of the method remained under 2%. The effect of acid treatment on the Ca content in enamel was demonstrated.

Acid Etching, Dental↗
PubMed1982

Zn and Cu content in human cancellous bone.

Duplicate cancellous bone samples from the iliac crest were obtained from autopsies of 88 persons with a normal mineral status and 50 having osteoporotic change due to chronic immobilizing diseases. The following parameters were determined: the minimal density with gamma-ray attenuation, the compressive strength with a strain transducer, the concentrations of Ca, Mg, Cd, Co, Cu, Mn, Ni, Li, Pb, Sr and Zn with an atomic absorption spectrophotometer and the concentration of F with an ion-selective electrode. The data were analyzed with linear multiple regression analysis. Altogether 34.8 per cent of the Zn concentration was accounted for in all the variables. The selected variables, after the nonsignificant and those with very low explanatory power were removed, explained 38.3 per cent. The two most important variables were the F concentration (16.1 per cent) and Cu concentration (13.7 per cent). The third variable was Mn concentration (8.5 per cent). All variables explained 41.7 per cent of the Cu concentration and five selected variables 40.7 per cent, respectively. The concentration of Zn explained itself as much (20.1 per cent) as four other variables (Ca 7.7 pe cent, Mn 5.9 per cent, Sr 3.9 per cent and Co 3.2 per cent) together. Age and sex did not significantly affect the concentration of Zn and Cu. No remarkable difference was found between the bone samples representing a normal mineral status and osteoporosis.

Adolescent↗
PubMed1981

Zn concentration of human subgingival calculus related to F, Mg and Cu contents.

F and Zn content of human subgingival calculus was studied with respect to its Ca, Mg, Cu, Fe and Ph contents. The material consisted of 60 subgingival calculus samples from 60 persons. The element concentrations were determined with an atomic absorption spectrophotometer except for the F content, which was measured with an ion-selective electrode. The data were analyzed using the multiple linear regression analysis. 24% of F content was explained by Zn and none of the other elements were significantly related to F content. Altogether, 55.4% of Zn content was accounted for in all variables. The selected variables after the removal of nonsignificant ones explained 54.8%. The most important variable was F (24.0%) and the explanation power of Cu was 18.3% and of Mg 12.5%. The regression coefficients of these variables were positive. The mean +/- s.d. concentration of F in the samples was 221.2 +/- 174.1 micrograms/g and of Zn 498.6 +/- 499.1 micrograms/g, respectively.

Adult↗
PubMed1981

X-ray diffraction patterns in human dentin, enamel and synthetic apatites related to Zn concentration.

The crystallization of human dentin and enamel containing different concentrations of Zn was studied using X-ray diffraction analysis. The concentrations of Ca, Mg, Mn, Fe, Zn, Cu, Co, Ni, Sr and Pb in the samples were determined by atomic absorption spectrophotometry. The concentration of F was assayed with a combination fluoride electrode. The increase of the Zn concentration (microgram/g) from 150 to 572 in dentin was found to intensify apatite reflections indicating changes parallel to c-axis. A slight increase parallel to a-axis (or better crystallization) of lattices was demonstrated in both dentin and enamel. The increase of Zn concentration from 164 microgram/g to 692 microgram/g in enamel weakened 002 and 112 reflections. The effect of Zn on the crystallinity of synthetic apatite prepared at 37 degrees C was of the same kind as its effect on the dentin.

Adolescent↗
PubMed1981

Alveolar bone loss in relation to periodontal treatment need, socioeconomic status and dental health.

The distance from cemento-enamel junction to alveolar crest was studied in relation to periodontal treatment need, socioeconomic factors and dental health. The subjects (315) of the study were employees of a paper mill in Finland. Alveolar crest height was measured from orthopantomograms, periodontal treatment need was assessed by the Periodontal Treatment Need System (PTNS). Number of teeth, interproximal fillings and caries were determined clinically, and background information was obtained by questionnaires. On an average, the rate of alveolar bone loss was 0.6 mm in 10 years in the study population and 1.2 mm in subjects aged 30 to 45 years. The bone loss increased with decreasing number of teeth. Subjects with plaque retention had somewhat more severe bone loss than those with no inflammation or gingival inflammation only. Periodontal treatment need, age and number of remaining teeth altogether explained 42.8% of the bone loss when tested by multiple linear regression analysis.

Adult↗
PubMed1981

Effect of chlorhexidine on the release of lysosomal enzymes from cultured macrophages.

Exposure of rat's peritoneal macrophages to chlorhexidine at concentrations up to 0.01 per cent resulted in the release of lysosomal enzymes, e.g. chloride-dependent arginine aminopeptidase and beta-D-glucuronidase into the medium from resting cells. The activity of extracellular lactate dehydrogenase increased up to the concentration of 0.01% and then decreased with increasing chlorhexidine concentration. This could indicate a certain type of "mummifying" of the cells and/or their membranes. The incorporation of trypan blue was found in all cells after a rinse with 0.05 per cent or higher concentrations of chlorhexidine. The direct effect of chlorhexidine on these enzyme activities showed a slight activation of beta-D-glucuronidase and lactate dehydrogenase, but an inhibition of arginine aminopeptidase. Also the binding of chlorhexidine to cells was found. Low chlorhexidine concentrations caused an additional enzyme release from phagocytizing cells.

Aminopeptidases↗
PubMed1980

Effect of Zn and Mg on the formation of whitlockite in human subgingival calculus.

X-ray diffraction analyses were carried out from pooled samples of old subgingival calculus. Also the concentration of Ca, Mg, Zn, Sr, Pb, Fe and Cu from these samples were determined by means of atomic absorption spectrophotometry. The comparison of the samples containing almost the same Zn concentration and two different concentrations of Mg (9 mg/g and 16 mg/g) showed an increase of 2.0.10 and 220 whitlockite reflections with an increasing Mg concentration. The increase of Mg concentration shifted whitlockite reflections suggesting a contraction of a-axis. The increase of Zn concentration showed an increase of 2.0.10 and 220 reflections indicating the fitness of Zn into the lattice of whitlockite. No changes of a-axis were detectable. When comparing all diffractograms and the results obtained from chemical analyses, the presence of Zn-MG-whitlockite proved evident.

Calcium Phosphates↗