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Biomedical subjects

D Birkhed

Publications and source records attributed to D Birkhed.

At least 199 records · Page 11Linked to original sources
PubMed1977

Acid production from Lycasin, maltitol, sorbitol and xylitol by oral streptococci and lactobacilli.

The acid production from maltitol was compared with the acid production from hydrogenated starch hydrolysate (Lycasin), sorbitol and xylitol by a number of oral strains and reference strains of Streptococcus mutans, S. sanguis, S. salivarius, S. mitior, S. milleri, S. faecalis, S. faecium, S. avium, Lactobacillus casei and L. salivarius. The polyols were added to a final concentration of 1.0% to two different basal media. Incubation was performed at 37 degrees C for 7 days after which the pH was recorded. Maltitol was fermented only by the lactobacilli (about two thirds of the strains). Lycasin was fermented by all strains of S. faecalis, more than 90% of the lactobacilli, about half of the S. sanguis strains, about one third of the S. mutans strains, and by a few other streptococcal strains. Acid production from sorbitol was observed among more than 80% of the S. mutans strains and the S. faecalis strains and most of the lactobacilli strains. Sorbitol-fermenting strains of S. sanguis and of S. mitior, all isolated from sorbitol-consumers, were observed. No other sorbitol-fermenting streptococci were found. Only the reference strains L. salivarius subsp. salivarius ATCC 11741 and S. avium ATCC 14025 fermented xylitol.

Acids↗
PubMed1975

Influence of sugar content in soft bread on pH of human dental plaque.

Quantitative determination of monosaccharides, disaccharides and sorbitol by use of gas-liquid chromatography (GLC) was performed on thirty-three samples of different commercial soft bread. Maltose was found in all the bread samples. Fructose and glucose were found only in samples of sweetened bread. Sucrose was detected in 5 samples, lactose in 2, and sorbitol in 2. Up to 20 per cent of the fresh bread weight was found to be low-molecular weight carbohydrates. Plaque pH-changes were studied in 18 persons following a 30-second month rinse with each of 3 solutions: (1) 50% sucrose, (2) water extract of sweetened bread, and (3) water extract of unsweetened bread. Mouth rinsing with the extract of sweetened wheat bread (sucrose 7.7 per cent of the dough weight) caused pH-decreases in plaque which were significantly more pronounced than those induced by the water extract of unsweetened wheat bread.

Adolescent↗
PubMed1975

Separation of "sucrases" in supernatants of human dental plaque material and characterisation of the reaction products.

Dental plaque material, collected from five subjects, was pooled, homogenised and sonicated. The cell-free extracts and the remaining plaque suspension were incubated with sucrose. Approximately 14 per cent of the total "sucrase" activity was found in the cell-free extracts after homogenisation, 46 per cent in the cell-free extracts after sonication and 40 per cent in the remaining plaque suspension containing cell-fractions, respectively. Using gel chromatography of pooled plaque extracs from 10 subjects, active fractions were incubated with sucrose. The reaction products were isolated and characterised. The results indicate the presence of at least three groups of sucrose-splitting enzymes: dextransucrase, levansucrase and invertase.

Adolescent↗
PubMed1975

Structural studies on polysaccharides synthetised from sucrose by soluble enzymes in human dental plaque material.

Soluble enzymes in human dental plaque material were shown to synthetise a polysaccharide material when incubated with sucrose. The polysaccharide mixture was fractionated by gel chromatography and the major fraction (Mw congruent to 95,000) was characterised as a mixture of a alpha-(1 leads to 6)-linked glucan with branches linked alpha-(1 leads to 3) to the main chain and a beta-(2 leads to 6)-linked fructan with branches in the 1-position of the chain residues.

Adolescent↗
PubMed1975

Degradation of maltose and starch by human saliva and by supernatants of dental plaque material.

The pH-decrease in dental plaque in vivo after mouth rinses with solutions of sucrose and maltose has been compared. No statistically significant differences were found between the results obtained with these two disaccharides. Pooled samples of parotid saliva, centrifuged whole saliva and dental plaque supernatants were separated with the isoelectric focusing technique. The results suggest that maltose is hydrolysed in parotid saliva by the salivary alpha-amylase and in dental plaque by enzymes from sources other than the salivary glands, probably microorganisms. No bacterial alpha-amylases, separated from salivary alpha-amylase, were found in whole saliva specimens or in dental plaque supernatants. Quantitative determinations of "maltase" and amylase activities in parotid saliva, centrifuged whole saliva and dental plaque supernatants from 10 subjects were carried out. The highest enzyme activity of "maltase" was found in the samples of dental plaque and the highest amylase activity in parotid saliva specimens.

Amylases↗
PubMedDate not supplied

The relationship between plaque pH and glycemic index of various breads.

Plaque pH was studied during 60 min in situ in 10 subjects after eating various breads. The pH response was then compared to glycemic index (GI; calculated from the incremental blood glucose area) obtained from our earlier investigations. The following four products were tested: (1) barley kernel bread (BKB), (2) BKB, sourdough-fermented (BKBS), (3) white wheat bread (WWB), and (4) syrup-sweetened wheat-rye bread (SWRB). BKB was also tested with more intensive chewing and SWRB with the addition of fat. A 5% sucrose solution served as a control. The pH drops with all the breads were considerably smaller than with the sucrose solution during the first 15 min. From 30 min and onwards the breads gave similar, or even lower (SWRB) pH than sucrose. There was a great difference in pH response among the four breads, with the most pronounced pH fall for SWRB, followed by WWB (based on the AUC values). Intensive chewing of BKB increased, while the addition of fat to SWRB reduced the pH fall, in both cases by about 0.2 pH units. A high correlation (r = 0.94) between plaque pH and GI was found, i. e. the more pronounced the pH drop in plaque, the higher the GI in blood. Therefore, both from a cariogenic and from a metabolic point of view, breads with a low GI should be recommended.

Adult↗
PubMedDate not supplied

Evaluation of Carisolv for the chemo-mechanical removal of primary root caries in vivo.

The objective of this study was to evaluate a new chemo-mechanical method (Carisolv) for the removal of primary root caries in vivo in terms of efficiency, treatment time and patient perception. Thirty-eight patients participated in an open, randomised and controlled study. Of the 60 root carious lesions included, 34 were randomised for chemo-mechanical treatment and 26 for drilling. A within-subject comparison was used whenever the patient had two cavities, which was the case for 22 subjects. All the Carisolv-treated cavities became caries free, as did all but one of those treated with drilling, as judged by an independent examiner. Only 4 of 34 patients asked for anaesthesia in the Carisolv group compared with 6 of 26 patients in the drilling group. Of those who did not use anaesthesia, 12 individuals in the drilling group experienced some pain compared with none in the chemo-mechanical group (p<0.001). The mean treatment time for the Carisolv method was 5.9+/-2.2 min, compared with 4.5+/-2.0 min for drilling; time for anaesthesia excluded (p<0.05). No negative reactions or adverse effects were recorded during the study. All 55 teeth examined in the 1-year follow-up were found to be sensitive using an electric pulp tester, and there was no difference regarding the condition of fillings between the lesions treated with Carisolv and drilling. It can be concluded that root caries can be effectively removed using the Carisolv method. The longer treatment time was compensated by less need for anaesthesia.

Adult↗
PubMedDate not supplied

Caries incidence in young type 1 diabetes mellitus patients in relation to metabolic control and caries-associated risk factors.

The aim of this study was to evaluate the caries incidence in a group of young patients with type 1 diabetes mellitus over a 3-year period from the onset of the disease in relation to metabolic control and to caries-associated risk factors. Sixty-four children and adolescents (8-15 years of age) had their diabetes treated and monitored according to a standard medical protocol and received extensive preventive oral health care based on individual needs. Data on blood glucose and glycosylated haemoglobin (Hb A(Ic)) were collected from the medical records. Whole saliva was collected every 3rd month and secretion rate, buffer capacity, glucose concentration, mutans streptococci and lactobacilli counts were determined. Dental examinations, including radiographs, were carried out once a year. Patients with less good metabolic control (>8.0% Hb A(Ic)) exhibited higher glucose levels in resting saliva (p < 0.05) and a significantly higher caries incidence (p < 0.05) compared to those with good metabolic control. The most influential determinants for high caries development during the 3-year follow-up period were metabolic control (odds ratio, OR = 5.7), poor oral hygiene (OR = 6.5), previous caries experience (OR = 5.3) and high levels of salivary lactobacilli (OR = 5.0). The findings suggest that the level of metabolic control and traditional caries risk markers are important factors for caries development in children and adolescents with type 1 diabetes mellitus.

Adolescent↗
PubMedDate not supplied

Effect of a triclosan-containing toothpaste supplemented with 10% xylitol on mutans streptococci in saliva and dental plaque. A 6-month clinical study.

The aim of the present investigation was to evaluate the effect of the combination of triclosan and xylitol in toothpaste on mutans streptococci (MS) in saliva and dental plaque. 155 individuals with >10(5) MS/ml saliva were included in a 6-month double-blind clinical study. They were divided into three groups (n = 51-52) balanced according to their MS counts at baseline. Each group used one of the following types of dentifrice: (1) Colgate Total with the addition of 10% xylitol (Total-Xylitol), (2) Colgate Total and (3) Colgate Total without triclosan and without xylitol. Whole saliva and pooled plaque samples were obtained after 2, 4 and 6 months. When comparing the MS counts within the groups for saliva and plaque samples, Total-Xylitol showed significant reduction at all three sampling occasions (p < 0.001). Mean reduction at the 6-month sample for saliva was 0.81/ml and for plaque 0.89 per sample (log values). ANOVA revealed significant differences between Total-Xylitol and the two other products at 6 months for MS in saliva and dental plaque. The conclusion from this 6- month study is that the addition of 10% xylitol to a triclosan-containing dentifrice reduces the number of MS in saliva and dental plaque.

Adult↗