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Jorma Tenovuo

Publications and source records attributed to Jorma Tenovuo.

14 recordsLinked to original sources

Dental caries and salivary status in children with type 1 diabetes mellitus, related to the metabolic control of the disease.

The aim of this study was to investigate the relationship among type 1 diabetes mellitus, dental caries, and salivary status in children. The study comprised 68, 10-15-yr-old diabetics, and 68, age- and gender-matched non-diabetic controls. Diabetics were categorized into well-to-moderately controlled (HbA1c < 9.0%) and poorly controlled (HbA1c >or= 9.0%) groups. Caries was recorded by assessing lesion activity at non-cavitated and cavity levels. Teeth were examined visually for the presence of dental plaque. Saliva was analyzed for unstimulated and stimulated flow rates, buffer effect, mutans streptococci, lactobacilli, and yeasts. Diabetics had fewer caries and plaque, lower salivary flow rates and buffer effect, and more frequent growth of yeasts than their non-diabetic controls. Well-to-moderately controlled diabetics had fewer decayed surfaces and lower counts of mutans streptococci and yeasts than poorly controlled diabetics, but the level of metabolic control of diabetes had no influence on salivary flow rates and buffer effect. High caries levels in diabetics were significantly associated with age, plaque score, and decreased unstimulated salivary flow rate, but were not associated with the level of metabolic control of diabetes. High caries experience in this study population could be related to plaque accumulation and/or to changes in saliva induced by diabetes mellitus.

Adolescent↗

[Not Available].

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Letter↗

Origin, structure, and biological activities of peroxidases in human saliva.

Human whole saliva contains two peroxidases, salivary peroxidase (hSPO) and myeloperoxidase (hMPO), which are part of the innate host defence in oral cavity. Both hSPO as well as human milk lactoperoxidase (hLPO) are coded by the same gene, but to what extent the different producing glands, salivary and mammary glands, affect the final conformation of the enzymes is not known. In human saliva the major function of hSPO and hMPO is to catalyze the oxidation of thiocyanate (SCN(-)) in the presence of hydrogen peroxide (H(2)O(2)) resulting in end products of wide antimicrobial potential. In addition cytotoxic H(2)O(2) is degraded. Similar peroxidation reactions inactivate some mutagenic and carcinogenic compounds, which suggests another protective mechanism of peroxidases in human saliva. Although being target of an active antimicrobial research, the structure-function relationships of hSPO are poorly known. However, recently published method for recombinant hSPO production offers new tools for those investigations.

Amino Acid Sequence↗

Sensitivity of Helicobacter pylori to an innate defence mechanism, the lactoperoxidase system, in buffer and in human whole saliva.

Helicobacter pylori has frequently been isolated from human dental plaque, and oral spread via saliva is thought to be one of its principal modes of transmission. Among other innate defence systems human saliva contains peroxidase enzymes and lysozyme. The sensitivity of H. pylori to physiological concentrations of lactoperoxidase and its salivary substrate thiocyanate, and different amounts of hydrogen peroxide (H(2)O(2)) was investigated in buffer and in human whole saliva. The effect of lysozyme was also studied in saliva. All tested H. pylori strains, ATCC 43504(T) and five clinical isolates, were efficiently inhibited by the peroxidase system with high concentrations of H(2)O(2) in buffer. The inhibition was stronger at lower pH. However, in human saliva these high concentrations of H(2)O(2) generated less hypothiocyanite, the antibacterial product of the peroxidase system and the effects of the peroxidase system were weaker. Physiological concentration of lysozyme was not bacteriocidal against H. pylori, nor did it enhance the effect of the peroxidase system in saliva. Thus, further studies are needed to enhance the efficacy of peroxidase systems in human saliva to make it more beneficial not only against dental but also against gastric pathogens.

Buffers↗

Effects of a betaine-containing toothpaste on subjective symptoms of dry mouth: a randomized clinical trial.

Our aim was to study the effects of mildly flavoured sodium lauryl sulphate (SLS)-containing and detergent-free toothpastes with and without betaine (BET) on subjective symptoms of dry mouth in a randomised clinical trial. BET is an osmoprotectant that reacts with molecules to supply the surface with a water coating that protects cells from surfactants. Twenty-seven xerostomic patients and 18 healthy controls took part in the randomised, double-blind clinical trial with a crossover design. Three mildly flavoured toothpastes: (1) 4% BET, (2) 1% SLS and 4% BET, and (3) 1% SLS were used for six weeks each. The reference or washout paste contained neither SLS nor BET. The subjects' dental appointments were at the beginning of the trial and before and after the use of each toothpaste. At each appointment, the subjects were interviewed about subjective sensations of dry mouth (Visual Assessment Scoring (VAS) Index). The subjects did not report any adverse effects in connection with the use of the toothpastes. The VAS scores for lip dryness and eating difficulties were significantly lower for the BET paste (lip dryness: BET<BET+SLS; p < 0.005 and eating difficulties: BET<BET+SLS; p = 0.02; BET<reference; p = 0.003). The BET paste relieved dry mouth symptoms in 44% of the xerostomic patients, the corresponding figures for the other pastes being BET+SLS 22% (p = 0.002 as compared with BET), SLS 18% (p = 0.022), and reference 7% (p = 0.000). In conclusion, all the mildly flavoured toothpastes used in this study were well accepted by the xerostomic subjects. Thus, other toothpaste components may be more mucosa-irritating than just SLS, or else they enhance the effect of SLS. The detergent-free, BET-containing toothpaste appeared to be associated with relief of some symptoms of dry mouth.

Analysis of Variance↗

Susceptibilities of different Actinobacillus actinomycetemcomitans strains to lactoperoxidase-iodide-hydrogen peroxide combination and different antibiotics.

Actinobacillus actinomycetemcomitans has an important aetiological role in localized juvenile periodontitis and in progressive periodontitis in adults. A. actinomycetemcomitans is found mainly in periodontal pockets but also in whole saliva, a potential transmission medium. It is sensitive to peroxidase-halide systems, but the differences between periodontitis associated clinical isolates and type strains are unclear. The sensitivities of these 2 strain groups to lactoperoxidase (LP)-iodide (I(-))-hydrogen peroxide (H(2)O(2)) combinations were investigated, and the sensitivities were compared with the susceptibilities to four antibiotics. There was great variation between the sensitivities of different strains, but the 2 strain groups responded similarly. The LP (75 microg)-I(-) (100 nmol)-H(2)O(2) (1000 nmol) combination produced a similar degree of inhibition as 2 microg ampicillin. The LP-I(-) system might be a potential antimicrobial agent against A. actinomycetemcomitans transmission via saliva.

Aggregatibacter actinomycetemcomitans↗

Susceptibility of Fusobacterium nucleatum to killing by peroxidase-iodide-hydrogen peroxide combination in buffer solution and in human whole saliva.

Some Gram-negative anaerobic bacteria have been associated with the infection of tooth supporting tissues, i.e. periodontitis. Of these bacteria, Fusobacterium nucleatum is sensitive to lactoperoxidase/myeloperoxidase-iodide-hydrogen peroxide system in vitro, but salivary concentrations of thiocyanate abolishes the bactericidality. These bacteria are located in periodontal pockets, on oral mucosa and in saliva. Although F. nucleatum most probably does not belong to the group of main periodontal pathogens, it sustains its proportion in the periodontal flora when gingivitis progresses to periodontitis. In this study, the sensitivity of F. nucleatum to different horseradish peroxidase-iodide-hydrogen peroxide combinations was tested both in buffer and in sterilized human whole saliva. Horseradish peroxidase was chosen because it does not bind thiocyanate at pH > or = 6. After 1h incubation at 37 degrees C, the cell viability was estimated by plate count and with flow cytometer using LIVE/DEAD BacLight kit (Molecular Probes, USA). In saliva, the horseradish peroxidase (50 microg/mL)-iodide (2.5 mM)-hydrogen peroxide (2.5 mM) combination decreased the amount of viable bacteria to 37% compared to 85% in the control without any of the components when measured with flow cytometer. Replacement of buffer by saliva decreased the bactericidality of the peroxidase system. However, in buffer less iodide and hydrogen peroxide was needed to produce significant decrease in the number of viable bacteria when measured by plate count than with flow cytometer. Our study shows that horseradish peroxidase-iodide-hydrogen peroxide combination is able to kill F. nucleatum cells in saliva. Horseradish peroxidase-iodide-hydrogen peroxide combination may be useful to diminish the degree of re-colonization of periodontitis-associated bacteria after periodontal therapy and to inhibit the transmission of these bacteria via saliva.

Journal Article↗

The effects of two sodium lauryl sulphate-containing toothpastes with and without betaine on human oral mucosa in vivo.

The aim was to compare the effects of two sodium lauryl sulphate (SLS)-containing toothpaste formulations with and without betaine on human oral mucosa in vivo. The results are compared with the effect of a dry mouth toothpaste without SLS. Twenty subjects participated in the double blind, crossover study. The toothpastes with 1.2% SLS, 1.2% SLS and 4% betaine and with 4% betaine but not with SLS were placed on buccal mucosa in a test chamber and kept in place for 15 min. The condition of the mucosa was studied both visually and using electrical impedance (EI) for up to 45 min. Both SLS-containing pastes had a similar, irritating effect on the mucosa as judged both by the appearance of the mucosa and the EI measurements. The dry mouth toothpaste (with betaine only) showed no significant irritation of the mucosa. Betaine did not reduce the mucosa-irritating effect of the SLS-containing toothpaste formulation. The surfactant-free toothpaste did thus not irritate the human oral mucosa in vivo while the SLS-containing pastes did.

Adult↗

Stability and activity of specific antibodies against Streptococcus mutans and Streptococcus sobrinus in bovine milk fermented with Lactobacillus rhamnosus strain GG or treated at ultra-high temperature.

Passive local immunization against dental caries is a promising approach to its prevention, as clinical evidence of active oral or nasal immunization is still limited and controversial. By means of systemic immunization of pregnant cows with a multivalent vaccine, high titres of IgG antibodies against human cariogenic bacteria, Streptococcus mutans and Streptococcus sobrinus, were produced in bovine colostrum. The purified immune product (IP) of this preparation has a number of anticariogenic properties, such as inhibition of streptococcal adherence to saliva-coated hydroxyapatite and inhibition of glucosyltransferase enzymes. This study investigated whether IP antibodies remained active and functional when added to ultra-high temperature (UHT)-treated milk or to Lactobacillus rhamnosus GG (LGG)-fermented milk stored for an extended time. LGG was chosen because of its widely known health benefits in humans and animals. A commercial UHT toddler's milk was supplemented with IP and stored for 2 months at 5, 21 and 30 degrees C. The antistreptococcal titres in UHT milk did not decline at any temperature during storage, and UHT-IP inhibited the adherence of S. mutans for up to 2 months. This was not the case with UHT toddler's milk without IgG antibodies. Milk was fermented with live LGG cells in the presence or absence of 5% IP. The antistreptococcal titres declined to about 30% of the original titres after storage. Fresh milk alone slightly enhanced streptococcal adhesion but fresh milk with IP inhibited the adherence of S. mutans by over 50%. LGG-positive fermented milk without antibodies also inhibited (P < 0.05) the adhesion by about 40%. In both LGG-fermented and UHT immune milk, the activity of antibodies against cariogenic streptococci was maintained during the expected shelf-life of these products. From the anticariogenic point of view it may be beneficial to add bovine-specific antibodies against mutans streptococci to probiotic LGG-containing milk products.

Animals↗

Betaine reduces the irritating effect of sodium lauryl sulfate on human oral mucosa in vivo.

Our aim was to evaluate whether betaine has a protective effect during exposure of the human oral mucosa in vivo to sodium lauryl sulfate (SLS) or cocoamidopropylbetaine (CAPB) as measured with a multifrequency electrical impedance spectrometer (EI). Both detergents were used at the concentration of 2.0% w/v with and without 4.0% w/v betaine in distilled water in 20 volunteers, and 0.5% and 1.0% w/v SLS combined with 4.0% w/v betaine in 5 volunteers. EI measurements were taken before application of the test solutions, after their removal, and every 15 min up to 45 min. Both 0.5% and 1% SLS solutions showed a significant reduction in 3 of the 4 indices, indicating mucosal irritation after the 15-min exposure (P < 0.05), whereas 2% SLS did so in all 4 indices (P < 0.001). Betaine had no effect on the detergent-induced decline with either the 2% or the 0.5% SLS solutions. However, when combined with the 1% SLS solution, betaine significantly (P < 0.05) reduced mucosal irritation by abolishing decreases in indices MIX (magnitude index) and IMIX (imaginary part index) and lowering it for PIX (phase index). The 2% CAPB solution showed a significant (P < 0.05) reduction in all 4 indices after the 15-min exposure, but the effect was significantly weaker than that of 2% SLS (P < 0.05). Betaine did not reduce the irritating effect of 2% CAPB. These findings can be used in the development of less irritating products for oral health care.

Adult↗

The sensitivity of Porphyromonas gingivalis and Fusobacterium nucleatum to different (pseudo)halide-peroxidase combinations compared with mutans streptococci.

Previous studies have shown that the peroxidase system with iodide is particularly effective against Actinobacillus actinomycetemcomitans. In the present study, the effects of iodide, chloride and thiocyanate in combinations with lactoperoxidase (LP) and myeloperoxidase (MP) on the viability of Porphyromonas gingivalis, Fusobacterium nucleatum, Streptococcus mutans and S. rattus were analysed. Bacteria were incubated in buffer solution containing peroxidase, substrate(s) and H2O2 (all in oral physiological concentrations), and plated after 0, 0.5 and 1 h. The oxidation product of iodide was the most bactericidal against all the bacteria tested. The effect was significantly weaker on mutans streptococci. Physiological concentrations of thiocyanate abolished the effects of LP-H2O2-iodide and MP-H2O2-iodide/chloride combinations. Thiocyanate-peroxidase systems have already been used in oral hygiene products. The incorporation of iodide into these products could make them much more potent against periodontal pathogens, and also help to prevent transmission of these pathogens from person to person via saliva.

Animals↗

Mercury in saliva and the risk of exceeding limits for sewage in relation to exposure to amalgam fillings.

The concentration of total mercury in stimulated saliva was studied in humans with dental amalgam fillings and in 2 nonamalgam groups. The probability of exceeding the limits of mercury permitted in wastewater increased proportionally as the number of amalgam-filled surfaces increased. The mercury limit for sewage is 0.05 mg/l (= 250 nmol/l) effluent, according to the Council of European Communities directive 84/156/EEC. In neither of the nonamalgam groups was this limit exceeded, but 20.5% in the amalgam group exceeded the limit (p < .001). The risk of exceeding the limit increased 2-fold for every 10 additional amalgam-filled surfaces (odds ratio = 2.0; 95% confidence interval = 1.3, 3.3). These results demonstrate that humans, especially in populated areas, can be a significant source of mercury pollutants. As a consequence of mercury release, bacteria may acquire mercury resistance, as well as resistance to other antimicrobial agents, thus resulting in failure of antibiotic treatment.

Adult↗