Seven weeks feeding of magnesium and fluoride modifies plasma lipids of hypercholesterolaemic rats in late growth phase.

Recent findings indicated that a low fluoride supplement, especially with a low magnesium supplement in the basically low magnesium diet of genetically hypercholesterolaemic male RICO rats, may prevent the generation of atherosclerotic serum lipid profile. In the present study, several plasma lipids/lipoproteins were measured in the same strain of rats after a later growth phase. The control group C was fed an adequate diet with 45 per cent sucrose plus some cholesterol while the dietary fluoride was very low (1.

Saliva in non-insulin-dependent diabetic patients and control subjects: The role of the autonomic nervous system.

Objective: The purpose of this investigation was to study the flow rate and organic constituents of whole saliva in relation to autonomic nervous function in patients with non-insulin-dependent diabetes.

Study Design: We studied the associations of saliva factors and autonomic nervous function in 45 patients with non-insulin-dependent diabetes (mean age, 68 +/- 6 years) and 77 control subjects (mean age, 67 +/- 5 years). The metabolic evolution was well known over a 10-year period from the time of diagnosis.

Accumulation of strontium and fluoride in approximal dental plaque and changes in plaque microflora after rinsing with chlorhexidine-fluoride-strontium solution.

Objectives: To find out if strontium is incorporated into plaque and enamel in vivo during a 2-week rinsing period with a chlorhexidine-fluoride-strontium solution and to determine the effects of the rinsing on the numbers of mutans streptococci and lactobacilli in plaque.

Subjects And Methods: A total of 18 adult participants rinsed their mouths twice a day for 2 weeks, first with a placebo solution and subsequently, separated by a 1-week interval without rinsing, with a chlorhexidine gluconate (0.05%)-sodium fluoride (0.

Effects of dietary fluoride and magnesium supplements on cyclic adenosine monophosphate (cAMP), calcium and magnesium levels in aorta of genetically hypercholesterolaemic RICO rats.

Previous observations have suggested that low intakes of fluoride prevent pathological calcifications of internal organs, including the aortic wall, in experimental animals, fed a basically low magnesium diet. Our group found recently that fluoride has some potentially preventive effect against atherosclerotic serum lipid profiles in genetically hypercholesterolaemic rats. To study whether the apparently positive potential of fluoride against atherosclerosis is also reflected in aortic tissue, through its well known activation of adenylate cyclase, the aortic cAMP content of the rats used in our recent study was determined.

Identification of Bacteroides forsythus in subgingival dental plaque with the aid of a rapid PCR method.

Bacteroides forysthus has been shown to be prevalent among patients with periodontitis. Conventional microbiological methods used to identify this bacterium, however, are laborious and time-consuming and are therefore not well-suited for screening purposes. We have developed a polymerase chain-reaction (PCR) method which is rapid, specific, and simple to perform and does not require other sample pre-treatment except a brief centrifugation.

Transgenic mice expressing the human ornithine decarboxylase gene under the control of mouse metallothionein I promoter.

We have generated a transgenic mouse line harbouring the human ornithine decarboxylase gene under the control of mouse metallothionein I promoter. Even in the absence of an exposure to heavy metals, ornithine decarboxylase was over-expressed in heart, testis, brain, and especially in liver, of the transgenic animals. An exposure of the transgenic mice to zinc further enhanced the enzyme activity to a level which in liver represented up to 8000-fold increase in comparison with non-transgenic animals.

Residual monomer content and its release into water from denture base materials.

Objectives: The aim of this study was to determine the content and amount of residual monomer released from heat-cured and chemical-cured polymethyl methacrylate (PMMA) during storage in water.

Methods: Residual monomer was extracted from ground PMMA with tetrahydrofuran and from the storage water with n-hexane. Samples were analyzed by using HPLC-chromatography.

Simultaneous detection of Actinobacillus actinomycetemcomitans and Porphyromonas gingivalis by a rapid PCR method.

The identification of periodontal pathogens by conventional methods is time-consuming and difficult. Therefore, a multiplex PCR method for simultaneous detection of Actinobacillus actinomycetemcomitans (A.a.

Serum lipoprotein levels in genetically hypercholesterolaemic RICO rats: effects of a high-sucrose-cholesterol diet without or with altered magnesium and fluoride content.

Genetically hypercholesterolaemic RICO rats (male, 6 weeks old) were randomly distributed into 6 experimental groups. The zero-time basal group A was sacrificed at the start of the experiment while the other groups were fed for 6 weeks and then sacrificed. Group B was fed a stock diet.

Development of a rapid PCR method for identification of Helicobacter pylori in dental plaque and gastric biopsy specimens.

A rapid and simple polymerase chain reaction (PCR) method was developed to detect Helicobacter pylori in gastric biopsy specimens and dental plaque samples. The primers were targeted to the 16S rRNA sequence of Helicobacter pylori strain ATCC 43504. The system was found to have a theoretical detection level of 0.

In vitro fatigue fracture of an acrylic resin-based partial denture: an exploratory study.

In this study the fatigue life of heat-cured acrylic resin test specimens shaped as maxillary partial dentures was examined. Ten test specimens were prepared from polymethyl methacrylate and were tested by a constant force fatigue test at 150 N immersed in +37 degrees C water. The fatigue-fracture surfaces of the test specimens were compared with a one-bend fracture surface of the control specimen by scanning electron microscopy.

Enamel dissolution in relation to fluoride concentrations in the fluid of dental plaque-like layers of precultured Streptococcus sobrinus.

Two experiments were conducted to find out what concentration of fluoride (F), when added as NaF to the fluid of an in vitro caries model, would be sufficient for full protection of the underlying enamel during a long (20 or 40 h) fall in 'plaque' pH. An existing caries model with bovine enamel and Streptococcus sobrinus 'plaque' was employed, while the fluid phase was initially either fully or partially saturated with tricalcium phosphate. In the model with fully saturated and more strongly buffered fluid, a 10 parts/10(6) addition of F to the fluid phase caused no inhibition of the pH fall.

Effect of fluoride varnish and solution on enamel erosion in vitro.

The effect of fluoride varnish and solution on initial enamel erosion was studied. Enamel specimens prepared from human third molars were treated for 24 h with Duraphat varnish (2.26% F) or for 48 h with NaF solution (1.

Flow rate and composition of whole saliva in rural and urban Tanzania with special reference to diet, age, and gender.

The association of flow rate and biochemical and microbiological characteristics of saliva with diet was studied in 83 12-year-old children and in 127 adults (84 in the age group 35-44 years, 43 in the age group 65-74 years) living in rural and urban communities in Tanzania. No significant differences were observed between the salivary flow rates of the rural and urban subjects. The mean salivary flow rates were slightly lower in women than in men and significantly lower in the 12-year-old children than in the two older age groups (p < 0.

Plaque accumulation on glass ionomer filling materials.

It has been suggested that fluoride released by glass ionomers inhibits the growth of plaque. The aim of this study was to compare plaque accumulation on glass ionomers and composite. The materials tested were (1) freshly mixed glass ionomer (Ketac-Fil), (2) artificially aged glass ionomer (Ketac-Fil), (3) freshly mixed silver glass ionomer (Ketac-Silver) and (4) light-cured hybrid composite (Valux).

Free amino acid levels in oral fluids of normal subjects and patients with periodontal disease.

The content of free amino acids in submandibular, parotid and whole saliva and in gingival fluid was measured by automatic analyser in patients with progressive periodontitis and in controls. The concentration of individual amino acids showed considerable variation in all the fluids. Two amino acids, proline and delta-aminovaleric acid, were never found in gingival fluid or in submandibular and parotid saliva, although detectable in whole saliva.

Gingival fluid, beta 2-microglobulin and protein levels as indicators of periodontal disease.

beta 2-microglobulin (beta 2-m), lysozyme and protein concentrations in gingival fluid were analyzed in 19 patients with severe periodontitis and in 19 controls devoid of any clinical signs of inflammation. A significant increase of the total protein and beta 2-m levels was found in periodontal subjects. In contrast, lysozyme concentration did not reflect the inflammatory status of the periodontium.

Protection by F, I, Sr, and combinations against fermentation attack by Streptococcus sobrinus artificial plaque on bovine enamel.

Labial surfaces of 64 bovine incisors (8 teeth/treatment) were subjected to 1-min treatment with (1) 500 ppm Sr, (2) 0.5% I2 plus 1% KI solution, (3) F varnish treatment (Duraphat) for 24 h, or (4) combined treatments. The treated teeth were incubated under an artificial Streptococcus sobrinus plaque for 10 days.

Sialochemistry in mucosal lesions of the tongue: electrolytes and total protein.

A total of 39 patients with tongue diseases and 17 controls were subjected to chemical analysis of saliva to determine whether tongue lesions are correlated with the composition of the saliva. The salivary flow rate, total protein, phosphate and electrolyte content (Na, K, Ca) were measured in unstimulated and stimulated saliva. The results indicate that disturbed salivary secretion could be revealed in patients with filiform atrophy and those with hairy tongue.

Salivary IgA, lysozyme and beta 2-microglobulin in periodontal disease.

The concentrations of IgA, lysozyme and beta 2-microglobulin (beta 2-m) were quantitated in wax-stimulated mixed saliva from 28 patients with severe periodontitis and from 28 healthy controls. The mutual correlations between IgA, lysozyme and beta 2-m were determined. In patients with periodontitis decreased lysozyme concentrations were detected when compared with controls (P less than 0.

Statistical evidence for the relation between citrate and carbonate in human cortical bone.

Bone specimens from the anterior iliac crest were collected post-mortem from 128 subjects whose death had been primarily caused by acute coronary disease or accidents. The cortical bone was separated and used for the following determinations: citrate by an enzymatic method, carbon dioxide by microdiffusion, chloride and phosphorus by spectrophotometry, fluoride by the ion-selective electrode technique, and Ca, Mg, Zn by atomic absorption spectrophotometry. The citrate concentration (+/- SD) was 10.

Relationships between carbonate, sex and other macroelements in human whole enamel.

Enamel samples were prepared from 40 teeth and CO3, P, F, Ca, Mg and Zn concentrations were determined. The carbonate concentration was higher in women than in men (P = 0.018), otherwise no sex dependence was found.

A scanning electron microscopic study of bacterial penetration of human enamel in incipient caries.

In 23 human teeth, cracked enamel under white spot lesions without any visible loss of tooth substance was examined. Bacterial contamination from the enamel surface was prevented by brushing and consequent fixing of the remaining surface coatings before the enamel was fractured. In 7 of 23 specimens, bacterial colonies were observed under the enamel surface, sometimes as deep as the enamel-dentine junction and the dentine.