Jukka H. Meurman

Effect of long term consumption of probiotic milk on infections in children attending day care centres: double blind, randomised trial

Abstract Objective: To examine whether long term consumption of a probiotic milk could reduce gastrointestinal and respiratory infections in children in day care centres. Design: Randomised, double blind, placebo controlled study over seven months. Setting: 18 day care centres in Helsinki, Finland. Participants: 571 healthy children aged 1-6 years: 282 (mean (SD) age 4.6 (1.5) years) in the intervention group and 289 (mean (SD) age 4.4 (1.5) years) in the control group. Intervention: Milk with or without Lactobacillus GG. Average daily consumption of milk in both groups was 260 ml. Main outcome measures: Number of days with respiratory and gastrointestinal symptoms, absences from day care because of illness, respiratory tract infections diagnosed by a doctor, and course of antibiotics. Results: Children in the Lactobacillus group had fewer days of absence from day care because of illness (4.9 (95% confidence interval 4.4 to 5.5) v 5.8 (5.3 to 6.4) days, 16% difference, P=0.03; age adjusted 5.1 (4.6 to 5.6) v 5.7 (5.2 to 6.3) days, 11% difference, P=0.09). There was also a relative reduction of 17% in the number of children suffering from respiratory infections with complications and lower respiratory tract infections (unadjusted absolute % reduction −8.6 (−17.2 to −0.1), P=0.05; age adjusted odds ratio 0.75 (0.52 to 1.09), P=0.13) and a 19% relative reduction in antibiotic treatments for respiratory infection (unadjusted absolute % reduction −9.6 (−18.2 to −1.0), P=0.03; adjusted odds ratio 0.72 (0.50 to 1.03), P=0.08) in the Lactobacillus group. Conclusions: Lactobacillus GG may reduce respiratory infections and their severity among children in day care. The effects of the probiotic Lactobacillus GG were modest but consistently in the same direction. What is already known on this topic Children attending day care centres are at high risk of respiratory and gastrointestinal infection The successful prevention of respiratory infections could be extremely useful for families and for society in general Short term use of probiotic bacteria has been shown to reduce the severity of rotavirus diarrhoea and the incidence of diarrhoea associated with the use of antibiotics What this study adds In a double blind, randomised, long term study milk containing Lactobacillus GG slightly reduced the incidence of respiratory infections and antibiotic treatment in children

Effect of Long–Term Consumption of a Probiotic Bacterium, Lactobacillus rhamnosus GG, in Milk on Dental Caries and Caries Risk in Children

Lactobacillus rhamnosus GG, ATCC (LGG), has shown antagonism to many bacteria including mutans streptococci. This randomized, double–blind, placebo–controlled intervention study was designed to examine whether milk containing LGG has an effect on caries and the risk of caries in children when compared with normal milk. 594 children, 1–6 years old, from 18 municipal day–care centres were included. The children received the milk with meals from coded containers 5 days a week in the day–care centres for 7 months. The children’s oral health was recorded at baseline and at the end, using WHO criteria. The caries risk was calculated based on clinical and microbiological data, comprising mutans streptococcus levels from dental plaque and saliva. The risk was classified as high if the child had a dmft/DMFT or initial caries score >0, and a mutans streptococcus count ≧105 CFU/ml. The results showed less dental caries in the LGG group and lower mutans streptococcus counts at the end of the study. LGG was found to reduce the risk of caries significantly (OR = 0.56, p = 0.01; controlled for age and gender, OR = 0.51, p = 0.004). The effect was particularly clear in the 3– to 4–year–olds. Thus, milk containing the probiotic LGG bacteria may have beneficial effects on children’s dental health.

Oral health, atherosclerosis, and cardiovascular disease.

During the last two decades, there has been an increasing interest in the impact of oral health on atherosclerosis and subsequent cardiovascular disease (CVD). The advent of the inflammation paradigm in coronary pathogenesis stimulated research in chronic infections caused by a variety of micro-organisms-such as Chlamydia pneumoniae, Helicobacter pylori, and cytomegalovirus-as well as dental pathogens, since these chronic infections are thought to be involved in the etiopathogenesis of CVD by releasing cytokines and other pro-inflammatory mediators (e.g., C-reactive protein [CRP], tumor necrosis factor [TNF-alpha]) that may initiate a cascade of biochemical reactions and cause endothelial damage and facilitate cholesterol plaque attachment. Yet, due to the multi-factorial nature of dental infection and CVD, confirming a causal association is difficult, and the published results are conflicting. The main deficit in the majority of these studies has been the inadequate control of numerous confounding factors, leading to an overestimation and the imprecise measurement of the predictor or overadjustment of the confounding variables, resulting in underestimation of the risks. A meta-analysis of prospective and retrospective follow-up studies has shown that periodontal disease may increase the risk of CVD by approximately 20% (95% confidence interval [CI], 1.08-1.32). Similarly, the reported risk ratio between periodontal disease and stroke is even stronger, varying from 2.85 (CI 1.78-4.56) to 1.74 (CI 1.08-2.81). The association between peripheral vascular disease and oral health parameters has been explored in only two studies, and the resultant relative risks among individuals with periodontitis were 1.41 (CI 1.12-1.77) and 2.27 (CI 1.32-3.90), respectively. Overall, it appears that periodontal disease may indeed contribute to the pathogenesis of cardiovascular disease, although the statistical effect size is small.

Short-term consumption of probiotic-containing cheese and its effect on dental caries risk factors

Cheese is known to contain compounds that reduce the risk of dental caries. The long-term consumption of milk containing Lactobacillus rhamnosus GG, ATCC 53103 (LGG), has been shown to reduce caries risk in children. The aim of the present study was to examine whether short-term consumption of cheese containing LGG and Lactobacillus rhamnosus LC 705 would diminish caries-associated salivary microbial counts in young adults. Altogether, 74 18-35 year-old subjects completed this double-blinded, randomised, placebo-controlled study. During the 3 week intervention, the subjects ate 5 x 15 g cheese per day. Oral examinations were made before and after the study. Stimulated salivary secretion rates, buffer capacity and counts of salivary Streptococcus mutans, yeast and lactobacilli were evaluated before and after the intervention and after a 3 week post-treatment period. The results showed no statistically significant difference between the groups in Streptococcus mutans counts after the intervention, but during the post-treatment period there was a significantly greater reduction in these counts in the intervention group compared to the control group (P=0.05). However, Streptococcus mutans counts decreased in 20% (P=0.01) and yeast counts in 27% (P=0.005) of all the subjects, regardless of the intervention group. Results from logistic regression showed a trend indicating that probiotic intervention might reduce the risk of the highest level of Streptococcus mutans (OR=0.37, 95% CI 0.08-1.75, P=0.21) and salivary yeasts (OR=0.40, 0.09-1.71, P=0.22).

Probiotics Reduce the Prevalence of Oral Candida in the Elderly : a Randomized Controlled Trial

Overgrowth of oral yeast is a common problem among the elderly. Probiotic bacteria are known to inhibit the growth of pathogenic microbes. We tested the hypothesis that cheese containing probiotic bacteria can reduce the prevalence of oral Candida. During this 16-week, randomized, double-blind, placebo-controlled study, 276 elderly people consumed daily 50 g of either probiotic (n = 136) or control cheese (n = 140). The primary outcome measure was the prevalence of a high salivary yeast count (≥ 104 cfu/mL) analyzed by the Dentocult® method. The prevalence decreased in the probiotic group from 30% to 21% (32% reduction), and increased in the control group from 28% to 34%. Probiotic intervention reduced the risk of high yeast counts by 75% (OR = 0.25, 95%CI 0.10–0.65, p = 0.004), and the risk of hyposalivation by 56% (OR = 0.44, 95%CI 0.19–1.01, p = 0.05). Thus, probiotic bacteria can be effective in controlling oral Candida and hyposalivation in the elderly.

Poor dental status increases acetaldehyde production from ethanol in saliva: a possible link to increased oral cancer risk among heavy drinkers

Epidemiological data support evidence that poor dental status increases oral cavity cancer risk especially among heavy alcohol consumers, but the causality of this finding is unclear. The enzymatic conversion of ethanol by the physiological oral microflora may lead to an accumulation of the highly carcinogenic intermediate acetaldehyde. This study was conducted to evaluate the role of dental status on the microbial production of acetaldehyde from ethanol in saliva. The microbial acetaldehyde production from ethanol was related to the dental score in 132 volunteers. After adjustment for smoking, alcohol consumption, age and gender, poor dental status was shown to lead to an approximately twofold increase in salivary acetaldehyde production from ethanol (P=0.02). Our results could be an important factor underlying the role of poor dental hygiene and status in oral cancer risk associated with ethanol drinking.

Xerostomia and hyposalivation: causes, consequences and treatment in the elderly.

Xerostomia and salivary gland hypofunction (SGH) are prevalent in elderly populations, causing much discomfort and even difficulties in eating. SGH also increases the occurrence and severity of oral diseases and makes the patient susceptible to candidiasis. The principal causes of SGH and xerostomia are systemic diseases and drugs used daily. The diagnosis of SGH and xerostomia is based on simple methods, of which measuring both unstimulated and stimulated salivary flow rate is the most important. Treatment calls for proper management of underlying disease, avoidance of all unnecessary medications, and topical remedies such as artificial saliva substitutes. However, good hydration is essential in the elderly with SGH and xerostomia, and water is the drink of choice. In extremely difficult cases, for instance in patients receiving radiotherapy for cancer of the head and neck regions, parasympathomimetic drugs may be administered if no contraindications exist.

Scanning Electron Microscopic Study of the Effect of Salivary Pellicle on Enamel Erosion

A bovine tooth model system was used to study the effect of experimental salivary pellicle on enamel erosion. Test blocks with varnish-covered control surfaces in each specimen were immersed into an acidic cola beverage (pH 2.6) for 120 min, either with or without the pellicle which was grown for 7 days by using clarified human saliva. After immersion, the pellicle was removed from some specimens with 10% sodium hypochlorite (20 h at 20 degrees C) and ultrasonic bath (60 s) to study its effect on erosion. All specimens were then studied in the scanning electron microscope. The specimens without pellicle (positive controls) showed gross erosion with prism core dissolution in all study blocks. The specimens with pellicle showed occasionally a film-like integument covering the apparently intact test surfaces with adjacent enamel surfaces slightly eroded. The erosion, however, was not of the same magnitude as in the positive controls. After removing the pellicle, the enamel surfaces showed pitted appearance of the prism heads; the demineralization seemed to attack more the prism sheath areas. Thus, salivary pellicle was found to protect the underlining enamel from erosion in vitro.

Dental erosion and upper gastrointestinal disorders

The orodental status, particularly dental erosions, of 109 patients with upper gastrointestinal symptoms was examined. In 44 patients, the underlying pathosis was associated with increased acid output in the stomach (reflux esophagitis or duodenal ulcer), while in 48 patients who underwent cholecystectomy, the duodenogastric reflux was alkaline. In 17 patients with gastric ulcer, the gastric secretion was usually normal. The diagnoses were made with gastroscopy. Seven patients with dental erosion were found, and they all came from the group of 35 dental patients with reflux esophagitis or duodenal ulcer. No erosions were seen in the other diagnostic groups (F = 0.02). Thus, gastrointestinal disorders with increased output of gastric acid may be linked with dental erosions. The finding emphasizes the need for accurate diagnosis and appropriate treatment of patients with upper gastrointestinal symptoms in order to avoid irreversible lesions in the teeth.

Oral and dental manifestations in gastroesophageal reflux disease.

One hundred seventeen patients with reflux disease were examined with respect to the severity of their disease and oral, dental, and salivary findings. Twenty-eight patients had dental erosion, whereas the remaining 89 patients did not. No mucosal changes could be observed to be linked with the reflux disease. In the mean, the patients with erosion were older (54 versus 49 years), and the mean duration of their reflux disease was longer in comparison to those without erosion (17 versus 11 years, respectively). The severity of the reflux disease was more marked among patients with erosion than in those without as assessed by esophagogastroduodenoscopy, the Maratka classification, histologic examination of gastric and esophageal biopsy specimens, and 24-hour esophageal pH monitoring. No statistically significant differences were observed between the groups in any salivary parameters studied, although the number of patients with low salivary-buffering capacity was higher among those with erosion than among those without. Patients taking beta-blocking agents or tranquilizers had more erosion than those who did not take these medications. The severity of the reflux disease was not associated with any subjective symptoms in the mouth or pharynx. The frequency of consumption of acidic drinks and foodstuffs as determined by a questionnaire did not differ between the patients with and without dental erosion. Thus severe reflux disease of long duration was found to be potentially detrimental to the teeth, whereas milder forms of the disease need not cause dental side effects.