Keijo Paunio

Studies on periodontal conditions in asthmatic children

The effect of extrinsic asthma on periodontal conditions was studied in a group of 30 asthmatic children. Clinical examination revealed that asthmatic children had more gingivitis than their healthy controls. The asthmatic children who received an inhaled corticosteroid as treatment had more severe gingivitis compared with asthmatic children on disodium cromoglycate treatment. The amount of plaque was not altered. The peroxidase activity was assessed from whole saliva. The results revealed that this defense mechanism was not altered in asthma. An enzyme group which is involved in inflammation, the arginine aminopeptidases, was found to be slightly elevated in the gingival fluid of asthmatic children. The results indicate that gingival inflammation is increased in asthma.

The relation between tooth eruption and alveolar crest height in a human skeletal sample

It is commonly assumed that alveolar crest height increases with continuing tooth eruption unless affected by marginal inflammation. To test this hypothesis, the relation between eruption and alveolar crest height was examined in skulls from a sample consisting of the remains of 244 individuals from the late medieval period. The mandibular first and second molars and second premolars were analysed. The age of the skulls was determined on the basis of dental development and molar attrition. Radiographs were taken and points representing the levels of the inferior dental canal (IDC), root apices (AP), alveolar crest (AC), cementum-enamel junction (CEJ) and occlusal surface were determined on the radiographs. The level of the IDC was used as a reference not changing with age. The distances between the points were measured with a help of a computer-digitizer system. Variable IDC-AP increased with age, indicating continuous eruption of the teeth. The distance between AC and CEJ also increased while the distance between IDC and AC remained constant, showing that the alveolar crest height did not increase accordingly. The lack of inflammatory changes on the alveolar bone surface suggests that occlusal attrition may be compensated for by continuous eruption without bone growth in the alveolar margin.

A HISTOCHEMICAL METHOD FOR THE DEMONSTRATION OF AMINOPEPTIDASE B ACTIVITY

A histochemical method for the demonstration of aminopeptidase B activity is presented. The method is based on the specific activation of the enzyme by chloride ions present in physiologic concentrations (0.9% or 0.154 M) in the incubating medium, on the inhibition by phosphate ions and on the use of N-l-arginyl-2-naphthylamine as substrate. The liberated 2-naphthylamine was coupled with fast blue B.

Aminopeptidase B in Human Gingival Exudate as Affected by Reduced Oral Hygiene and Sugar Diet

The activity of aminopeptidase B, an arginine aminopeptidase probably involved in the inflammatory process, was measured in human gingival exudates collected from persons kept on various sugar diets. The test persons were divided into four groups, receiving in their diet either sucrose, glucose, fructose, or xylitol during a four days period, after which the gingival index and the activity of aminopeptidase B in the gingival exudates were determined. The same measurements were carried out after a two week period of normal diet and good oral hygiene. The activity of aminopeptidase B was high in all samples after the four days sugar diet, increasing in the following order: glucose, fructose, sucrose, xylitol. After the two week normal period the activity of aminopeptidase B was reduced to one half or one third of the initial values.

The effect of human dental plaque on bone resorption and hyaluronic acid synthesis in in-vitro cultures of fetal rat calvaria.

Dental bacterial plaque affects bone demineralization both in vivo and in vitro. Since hyaluronic acid may play a role in demineralization, calcium release into the media as a measure of bone resorption was correlated with the synthesis of [3H]-glucosamine-labelled macromolecules in bone culture. The synthesis of glycosaminoglycans was determined by both a Millipore method and by DEAE-cellulose chromatography. Addition of plaque extract to the culture media stimulated both the synthesis and release of hyaluronic acid to the culture media, while stimulating calcium release. Thus, the bone-demineralizing effect of dental plaque seems to be associated to the induced synthesis of hyaluronic acid.

Formation of dityrosine by human salivary lactoperoxidase in vitro

The study dealt with the formation of dityrosine - a cross-link in some proteins including collagen - by human salivary lactoperoxidase. Dityrosine formation was found at pH range 6.6 to 9.3 with maximum reaction velocity at pH 8.5. However, thiocyanate ions at physiological salivary concentrations inhibited dityrosine formation by 70 to 80 per cent compared with the optimum rate. The inhibition seemed to result from the competition of SCN ions and L-tyrosine for the same binding site on enzyme surface. The possibility of dityrosine cross-linking in vivo in human oral fluid seems to be limited compared with e.g. human milk or macaque saliva where the concentration of SCN ions is low but the activity of lactoperoxidase is considerably high.

The content of arginine aminopeptidases, hexosamine, and uronic acid sugars in gingival exudate as affected by short term sugar diets

The specific activity of arginine aminopeptidases (which are properly represented by aminopeptidase B) and the amount of hexosamines, uronic acids, serotonin and histamine was determined in gingival exudates obtained from persons kept for five days on various mild sugar diets (including sucrose, xylitol, fructose-xylitol, fructose-sorbitol, fructose-glucose, and sucrose-maltose). The sugars consumed during reduced oral hygiene did not differ as regards their ability to induce aminopeptidase B-activity. The enzyme activity towards N-L-arginyl-2-naphthylamine was somewhat higher in fructose-sorbitol, glucose-fructose, fructose-xylitol and xylitol groups than in the sucrose and sucrose-maltose groups. The sugars did not lead to any differences in the amount of uronic acids and hexosamines in the exudates. This concerned histamine and serotonin as well.

Caries Prevalence in Turner's Syndrome (45,X Females)

Dental caries prevalence in permanent teeth (DFS) was studied in 50 patients with Turners syndrome (45,X females) and 41 normal first-degree female relatives. Caries prevalence was lower in 45,X women than in controls, and this difference was more pronounced in the incisor region than in pre-molar and molar teeth.

Effect of xylitol and sucrose plaque on release of lysosomal enzymes from bones and macrophages in vitro.

Plaque formed during a 5-day xylitol or sucrose chewing gum diet was used as an irritating agent in bone and macrophage culture. The release of hydrolytic enzymes was monitored. The contents of protein, DNA, and ATP were analyzed, to characterize plaque formed during different dietary periods. The release of glycosidases and phosphatases was lower in the presence of xylitol plaque when compared with sucrose plaque as an immediate reaction in macrophage cultures at 3 h and also in bone cultures at 3 days. The results indicate that xylitol plaque had a less irritating effect on macrophages and bones in vitro than sucrose plaque according to the parameters used in this study.

Determination of radioactive proline and hydroxyproline by a simple paper-chromatographic procedure.

A simple method to separate and determine radioactive proline and hydroxyproline by paper chromatography is described. The localization of the imino acids after separation is achieved by direct nondestructive staining with 1-fluoro-2,4-dinitrobenzene dye. The imino acids are quantitated directly by liquid scintillation counting in the presence of paper strips. The method was applied to bone cultures with good reproducibility, sensitivity and linearity over a wide range of radioactivity. The procedure was also tested in fibroblast cultures. The results for hydroxyproline were in good correlation with the widely used method of Juva and Prockop (Juva, K. and Prockop, D.J. (1966) Anal. Biochem. 15, 77-83), in which hydroxyproline is oxidized to pyrrole, and then extracted and purified by column chromatography before counting radioactivity.