Saliva nitric oxide levels in relation to caries experience and oral hygiene

Expression of Nitric Oxide Synthase and Nitric Oxide Levels in Peripheral Blood Cells and Oxidized Low-Density Lipoprotein Levels in Saliva as Early Markers of Severe Dengue

Background

Severe dengue (SD), experienced by only a fraction of dengue patients, can be lethal. Due to the lack of early markers that can predict the evolution of SD, all dengue patients have to be monitored under hospital care. We discovered early oxidative stress markers of SD to identify patients who can benefit from early intervention before the symptoms appear.

Methods

The expression of inducible nitric oxide synthase (iNOS) in peripheral blood cells (PBC), nitric oxide (NO), and oxidized low-density lipoprotein (oxLDL) levels in plasma and saliva collected at early stages of dengue infection from 20 nonsevere dengue fever (DF) patients and 20 patients who later developed SD were analyzed in a retrospective nested case-control study.

Results

The expression of iNOS is significantly (P < 0.05) lower in patients who developed SD than in DF patients at admission within 4 days from fever onset. Median plasma NO concentration within 4 days from fever onset is also significantly (P < 0.05) lower in patients who developed SD (17.9 ± 1.6 μmol/L) than DF (23.0 ± 2.1 μmol/L). Median oxLDL levels in plasma within 3 days from fever onset is significantly (P < 0.05) lower in patients who developed SD (509.4 ± 224.1 ng/mL) than DF (740.0 ± 300.0 ng/mL). Median salivary oxLDL levels are also significantly (P < 0.05) lower in patients who developed SD (0.8 ± 0.5 ng/mL) than DF (3.6 ± 2.6 ng/mL) within 4 days from fever onset.

Conclusions

These findings suggest that the expression of iNOS (73% sensitivity, 86% specificity) and plasma NO (96% sensitivity, 61% specificity at 22.3 μmol/L; P < 0.05) may serve as early markers of SD within 3 days from fever onset. Salivary oxLDL levels may serve as early noninvasive markers of SD with a sensitivity and specificity, respectively, of 57% and 91% at 0.9 ng/mL; 76% and 55% at 2.3 ng/mL; and 100% and 50% at 4.6 ng/mL (P < 0.05) within 4 days from fever onset.

The Impact of Dental Environment Stress on Dentition Status, Salivary Nitric Oxide and Flow Rate

Aim:

This study aimed to assess the dental caries experience among dental students with different levels of dental environment stress in relation to salivary nitric oxide (NO) and flow rate of whole unstimulated saliva.

Materials and Methods:

The study involved 300 dental students. They were classified into three categories (mild stress, moderate stress, and severe stress) according to dental environment stress questionnaire (DESQ); clinical examination for dental caries was carried out. Unstimulated salivary samples were collected from the mild and severe stress groups for measuring the salivary flow rate. Estimation of salivary NO was carried out by using salivary NO test strips. All data were analyzed using the Statistical Package for the Social Sciences software, version 21.0 (SPSS, Chicago, Illinois).

Results:

Dental caries experience was higher among severe and moderate stress groups with nonsignificant differences (P > 0.05). Mean value of salivary flow rate was lower among severe stress group with nonsignificant differences (P > 0.05). NO was significantly higher among severe stress group (P < 0.05). Flow rate was weak negatively correlated with caries experience among both mild and severe stress groups except for the decay surface (DS), which was weak positive among mild stress group. NO was weak negatively correlated with DS among both mild and severe stress groups. All these correlations were statistically not significant (P > 0.05).

Conclusion:

Dental environment stress appears to affect oral health, shown by higher dental caries among dental students with severe dental environment stress by affecting the normal level of salivary flow rate and NO.

Age and gender characteristics of the biochemical composition of saliva: Correlations with the composition of blood plasma

Background

Recently, the attention of researchers to the study of the properties of human saliva, as a material with unique properties and diagnostic capabilities, has increased.

Research objective

to study the connection of the biochemical composition of saliva and blood plasma in the norm, depending on gender and age.

Methods

107 volunteers took part in the study, including 46 female (37.2 ± 3.9 years old) and 61 male (36.1 ± 2.8 years old). In all samples of saliva and blood plasma, 16 biochemical parameters were determined, including mineral and protein composition, enzyme activity. Non-parametric statistical methods were used to process the data.

Results

It has been shown that it is difficult to establish an unambiguous relation between biochemical parameters of saliva and blood plasma. The calculation of the Spearman correlation coefficients showed that only 7 of the 16 parameters demonstrate the presence of a weak correlation between the content in saliva and plasma.

Conclusion

In general, the determination of the composition of saliva may have an independent diagnostic value; in this case, drawing a parallel with the composition of serum and blood plasma is not advisable. Nevertheless, the use of saliva in clinical laboratory diagnostics is associated with the need to establish criteria for the norm and pathology for each biochemical parameter.

Salivary nitric oxide, Simplified Oral Hygiene Index, and salivary flow rate in smokers and non-smokers: a cross-sectional study

Background: Salivary nitric oxide plays an important role as an antibacterial agent in the oral cavity. Here, we analyze salivary nitric oxide, Simplified Oral Hygiene Index (OHI-S) scores and the salivary flow rate in smokers and non-smokers which has not been done previously. Methods: A cross sectional study included 25 smokers and 25 non-smokers. Their OHI-S results were categorized as "good," "medium," or "bad." Unstimulated saliva samples were collected, and their nitric oxide concentration was measured using the Griess method. Results: The salivary flow rate in smokers was lower, at 0.30 ml/minute, compared to non-smokers who had a salivary flow rate of 0.33 ml/minute. This was statistically insignificant. There was a significant difference in the concentrations of nitric oxide between smokers and non-smokers (p < 0.05). Smokers had higher concentrations than non-smokers (185.4 µM Vs 114.60 µM). In addition, there was a moderate positive correlation (r = 0.305) between the concentration of salivary nitric oxide level and the OHI-S results. Conclusions: It was concluded that salivary nitric oxide concentration was higher in smokers, and the oral hygiene condition of smokers was poor.

Salivary nitric oxide, Simplified Oral Hygiene Index, and salivary flow rate in smokers and non-smokers: a cross-sectional study

Background: Salivary nitric oxide plays an important role as an antibacterial agent in the oral cavity. Here, we analyze salivary nitric oxide, Simplified Oral Hygiene Index (OHI-S) scores and the salivary flow rate in smokers and non-smokers which has not been done previously. Methods: A cross sectional study included 25 smokers and 25 non-smokers. Their OHI-S results were categorized as "good," "medium," or "bad." Unstimulated saliva samples were collected, and their nitric oxide concentration was measured using the Griess method. Results: The salivary flow rate in smokers was lower, at 0.30 ml/minute, compared to non-smokers who had a salivary flow rate of 0.33 ml/minute. This was statistically insignificant. There was a significant difference in the concentrations of nitric oxide between smokers and non-smokers (p < 0.05). Smokers had higher concentrations than non-smokers (185.4 µM Vs 114.60 µM). In addition, there was a moderate positive correlation (r = 0.305) between the concentration of salivary nitric oxide level and the OHI-S results. Conclusions: It was concluded that salivary nitric oxide concentration was higher in smokers, and the oral hygiene condition of smokers was poor.

Assessment of dental caries and salivary nitric oxide levels in children with dyspepsia

BACKGROUND

The increase in nitric oxide (NO) levels in the oral cavity and saliva have been associated with various oral diseases; however, the gastro-salivary interaction of NO remains controversial. Thus, the aim of this study was to determine and compare salivary NO levels of dyspeptic and non-dyspeptic healthy children and to conduct an evaluation of its association with dental caries.

METHODS

Seventy children with dyspepsia (dyspeptic group) and 30 children without any gastrointestinal complaints (control group) were included in the study. Two biopsies from the gastric tissues were collected from dyspeptic children for histopathologic examination. Oral examination involved the assessment of dental caries, gingival index, plaque index, buffering capacity, salivary flow rate and pH. Salivary Streptococcus mutans (S. mutans) and Lactobacilli sp. counts were performed by commercial kits. For the comparison of the normal distribution between dyspeptic and control groups, Student t-test and for the comparison of the non-normal distribution, Kruskal-Wallis and Mann-Whitney-U tests were used. Chi-square test was used for comparison of qualitative data and the Pearson correlation test was used to evaluate the association between certain variables. Significance was assessed at p < 0.05 level.

RESULTS

Helicobacter pylori (H.pylori) were found in gastric biopsies of 84.2% (59/70) of the dyspeptic children. While the mean salivary NO values did not differ significantly between gastric H.pylori positive, negative and control groups, the salivary NO level of the dyspeptic group (213.7 ± 51.68 μmol/dL) was found to be significantly higher than the control group (185.7 ± 16.66 μmol/dL). No significant relationship was found between the mean salivary NO values, DMFT/dmft numbers and other oral parameters.

CONCLUSIONS

The association of dental caries and salivary NO levels could not be considered specific in the current study. Although there were no statistically significant differences between salivary NO levels of gastric H.pylori positive, gastric H.pylori negative and control groups, greater salivary NO levels among dyspeptic children compared with the control group demonstrated that the concentration of NO in the saliva could be used as a biological marker in dyspepsia, which could lead to the improvement of more specified, uncomplicated and susceptible methods for analysis.