OBJECTIVE: The present study aimed to determine the salivary flow and metabolomic profile of stimulated and unstimulated saliva in children.
METHODS: Children who attended the Pediatric Dentistry Clinic of the State University of Rio de Janeiro -UERJ between 3 and 12 years of age were selected. Unstimulated and stimulated whole saliva, using mechanical stimulus, were collected. The samples were centrifuged at 12,000 g, 4oC for 1 h. The 1H- NMR spectra were acquired in 500 MHz equipment. The data were extracted into 0.03 ppm buckets in AMIX, and multivariate analysis (PLS-DA and O-PLS-DA) was performed in Metaboanalyst 2.0. For other analyses, such as salivary flow, the data was tabulated in the SPSS 20.0 statistical package, analyzed descriptively, and after applying the Wilcoxon test. The interval of confidence was set at 95%.
RESULTS: The mean age was 7.5 (± 1.94), and 47.0% (n = 31) were female, 63.6% (n = 42). The median flow rate for stimulated saliva was 0.74 (IC 0.10-2.40) and was statistically higher (p < 0.001; Wilcoxon test) than unstimulated was 0.39 (IC 0.00-1.80). Children older than seven years old also presented a higher difference between unstimulated and stimulated saliva (p = 0.003; Mann-Whitney test). The PLS-DA and O-PLS-DA demonstrated a different profile in stimulated and unstimulated saliva. Acetate, glucose, propionate, and lysine were higher in the unstimulated whole saliva than in stimulated saliva. Isoleucine, N-acetyl sugar, hydroxybutyrate, glutamate, leucine, propionate, butyrate, valine, isoleucine, succinate, saturated fatty acid, and histidine were found in greater amounts in the saliva of patients with stimulated saliva.
CONCLUSIONS: The stimulated saliva presented a higher flow rate, and older children exhibited a higher flow rate resulting from it\'s the stimulus. The mechanical stimulus increased the levels of the major metabolites.

UNASSIGNED: Diabetes Mellitus is a chronic disease characterized by uncontrolled blood sugar levels, which lead to end-organ damage. While the diagnosis and treatment of its complications have been extensively studied, the effect of Hyperbaric Oxygen Therapy (HBO2) on diabetes-related oral complications remains unexplored.
UNASSIGNED: This prospective clinical study aims to investigate the effect of HBO2 on diabetes-related oral complications.
UNASSIGNED: Twenty patients diagnosed with diabetic foot ulcers and scheduled for HBO2 were included in this study. We recorded stimulated and unstimulated saliva pH, buffering capacity, flow rate, and subjective symptoms such as dry mouth, halitosis, taste loss, difficulty swallowing, and clinical examination findings before HBO2 and after the 21st session.
UNASSIGNED: Upon comparing the findings, we observed a significant decrease in dry mouth and halitosis, periodontal disease severity, and healing of candida-related stomatitis and angular cheilitis. Despite not reaching statistical significance for other saliva parameters, the unstimulated salivary flow rate increased to normal limits (0.3-0.4 ml/min) in 6 out of 8 patients with a flow rate of less than 0.25 ml/min.
UNASSIGNED: Our study investigated the effect of HBO2 on diabetes-related oral complications for the first time, highlighting symptomatic relief for dry mouth and halitosis. Although our results are insufficient to report a definitive benefit, they underscore the need for further research on the oral health effects of HBO2.

This study investigated and compared the consistency and compressive strength of two commercially available paraffin wax chewing gums (Aurosan (AU) and GC Europe (GC)), as well as their impact on stimulated salivary flow rate. Instrumental texture analysis was uti-lized to assess the consistency and compressive strength of AU and GC during a 7-min chewing period. Subsequently, stimulated salivary flow rate (sSFR) was evaluated in healthy subjects using AU and GC over a 7-minute period. The compressive strengths from the pre-liminary test were compared over time with the sialometry data. Eighty-one test subjects, comprising 33 men and 48 women, participated. Over the 7-min measurement period, dif-ferences were observed in the total amount of saliva accumulated per minute. Direct com-parison of AU and GC revealed that regardless of age and gender, the amount of saliva formed after 1 min was 0.63 times less with AU than with GC (95% CI: 0.56 - 0.70; P < 0.001). The accumulated saliva volume with AU was also significantly lower than that with GC in the first 4 min (P = 0.016). However, from minute 5 onwards, the two products no longer showed statistical differences in the total amount of saliva. Comparison of the com-pressive strength of AU and GC showed that the values after 1 and 2 min were significantly higher for AU than for GC (P < 0.05); for all other time points, the compressive strength was higher for GC. In the mixed-effects model after log-transformation of compressive strength and saliva volume, GC exhibited decreasing saliva volumes with increasing compressive strength (P <0.001). Conversely, the opposite was observed for AU (P = 0.019). The study suggests that the consistency or compressive strength of paraffin wax chewing gums from different manufacturers could impact sSFR.

Dry mouth is a multifaceted condition which is caused by reduced salivary secretion. This study aimed to evaluate and compare the effects of different lozenge surface textures, tastes and acidity levels on stimulated salivary secretion for increased oral moistening in participants without hyposalivation. This randomized, double-blind, clinical crossover trial with before and after comparison involved 33 healthy volunteers. Five lozenges, including a baseline control (C), apple (A), sour (S), sour apple (SA) and granular pectin (P) were tested on five different days with all the subjects. Salivary flow, pH value, and subjective feeling (visual analog scale) were measured before and after consuming the lozenge each day. Throughout all trial days the unstimulated whole salivary flow (UWSF) averaged 0.65 ± 0.26 ml/min. Lozenges S, SA, and P showed higher stimulated whole salivary flow (SWSF) than C (P < 0.001) by more than 0.5 ml/min. Lozenge P, with a rough surface, demonstrated the highest difference between UWSF and SWSF, 2.41 ± 0.69 ml/min. The stimulated saliva with the lozenges containing acidifiers (S, SA and P) was more than 1.4 pH units lower compared to lozenges C and A (P < 0.001). Subjects reported the strongest subjective feeling of increased saliva with lozenges SA and P. Overall lozenges SA and P provided the best objective results in enhancing salivary flow rate and subjective feeling of increased salivary flow.

This study aimed to evaluate the effect of photodynamic therapy (PDT) on the salivary flow rate, secretory immunoglobulin A, and C-reactive protein levels in active smokers.
The present study is a prospective case-control study. Twenty active smokers were allocated to two groups randomly of ten participants each: the experimental group was irradiated while the control was exposed to sham irradiation by turning off the equipment. In the experimental group, methylene blue mediated PDT was applied both intra- and extra-orally over the major and minor salivary glands using a diode laser. 780 nm wavelength and 4 J/cm2 of energy were used to irradiate the 10 points of major salivary glands (6 for parotid and 2 for submandibular glands and 2 for sublingual glands). On the other hand, 660 nm was used to apply 10 J/cm2 of energy over the minor salivary glands at numerous points. The samples of the stimulated and unstimulated saliva were collected from both groups to assess the SFR. ELISA method was used to assess the level of salivary IgA levels, statistical analysis was done using a one-way ANOVA, and a p-value of <0.05 was considered significant.
The results showed a significant increment in salivary and secretory immunoglobulin A levels of subjects undergone photodynamic therapy. C-reactive protein levels were significantly decreased in subjects exposed to irradiation.
The present study concludes that photodynamic therapy significantly improves the salivary flow rate, secretory Immunoglobulin A, and oral health quality of life in smokers. The inflammatory salivary marker C-reactive protein, which is usually raised in smokers, is also reduced.

UNASSIGNED: Although there have been numerous studies on dental caries in children with Down syndrome, the reports are conflicting. Studies on salivary chemical composition of children with Down syndrome are limited.
UNASSIGNED: The study aims to evaluate and compare the dental caries experience, salivary flow rate, pH, buffering capacity, and concentration of sodium, potassium, calcium, phosphorus, total proteins, and sialic acid in children with Down syndrome and healthy controls.
UNASSIGNED: This was a cross-sectional study.
UNASSIGNED: Forty subjects with Down syndrome aged 5-18 years fulfilling the eligibility criteria from six special schools were selected by snowball sampling. Sixty healthy controls from six neighborhood schools fulfilling the eligibility criteria were selected by simple random sampling by matching the age, gender, and socioeconomic status. Sociodemographic data, oral hygiene practices, diet history and dental caries experience were recorded. About 6 mL of stimulated whole saliva was collected. Salivary flow rate, salivary pH, buffering capacity, and the concentration of sodium, potassium, calcium, phosphorus, total proteins, and sialic acid were determined.
UNASSIGNED: There was no significant difference in the mean proportional caries rate between the study and control group (P = 0.90). Salivary pH (P = 0.00) and salivary sodium concentration (P = 0.02) were significantly low in the study group than the control group. Salivary buffering capacity was significantly higher in the study group than the control group (P = 0.001).
UNASSIGNED: Dental caries experience of children with Down syndrome was similar to the healthy controls. School health programs could be implemented in special schools to improve oral and general health of special children.

Rodrigues RP, Vidigal MT, Vieira WA, Nascimento GG, Sabino-Silva R, Blumenberg C, Siqueira MF, Siqueira WL, Paranhos LR. Salivary changes in chronic kidney disease and in patients undergoing hemodialysis: a systematic review and meta-analysis. Journal of Nephrology. 2022 Mar 2:1-29.
The work has been partially funded by CAPES-Finance Code 001. The authors have also acknowledged The Brazilian National Council for Scientific and Technological Development (CNPq) and Minas Gerais State Agency for Research and Development, Brazil (FAPEMIG) for the support.
Systematic review with meta-analysis of data.

This study aimed to establish whether the modified Schirmer test could serve as a diagnostic tool for dry mouth, that is, whether it could reliably measure salivary film at selected locations within the oral cavity, and to identify levels of sensitivity/specificity and determine reference values. Therefore, a cross-sectional study (N = 120, mean age 63.5 [SD 13.9] years) was performed. The test was used at five locations (hard palate; buccal mucosa in molar region at 4 mm above occlusal plane; anterior tongue; lower lip; mouth floor), and results were recorded after 1, 2 and 3 min. A statistically significant discriminatory ability of the Schirmer test for the unstimulated salivary flow rates could be shown for the palate (at 3 min), buccal mucosa (at 1 min), mouth floor (at 1 min), and tongue (at 2 and 3 min) (areas under the curve 0.64-0.68), with individual sensitivity/specificity values depending on test location/time points. Thus, the modified Schirmer test has potential to become a simple and reproducible instrument for the detection of dry mouth based on low unstimulated salivary flow rates in dentistry and especially outreach care. Care must be taken concerning intraoral test location and measurement time.

OBJECTIVE: To investigate the effect of acid stimulation on salivary flow rate and compositions of human parotid and submandibular glands, so as to provide basis for comprehensive evaluation of salivary gland function in both health and disease status.
METHODS: In the study, 210 healthy participants\' whole saliva samples were collected under passive drooling, and their parotid gland and submandibular gland secretions were collected by negative pressure suction. 2% citric acid was dropped on the tip of tongue every 1 min for acid stimulation for a total of 5 times to collect stimulated whole saliva, parotid and submandibular gland saliva. The collected saliva was weighed and saliva flow rate was calculated. The K+, Na+, Cl-, Ca2+, total protein, total phosphorus and α-amylase in saliva samples were detected by biochemical analyzer, and the changing features of flow rate and compositions of different kinds of saliva were compared and analyzed.
RESULTS: After acid stimulation, saliva flow rate significantly increased. The increase proportion of parotid gland saliva (10.7 folds) was much higher than that of submandibular gland saliva (2.9 folds). The concentrations of Na+, Cl-, Ca2+, total protein and α-amylase in parotid gland saliva increased significantly (P < 0.05), but there was no significant difference in total phosphorus and K+ (P=0.89, P=0.34). The concentration of Na+ and Ca2+ in saliva of submandibular gland increased significantly(P < 0.05), the concentration of total phosphorus decreased significantly(P < 0.05), and the concentration of Cl- increased, but the difference was not significant(P=0.068). There was no significant difference in total protein, K+ and α-amylase (P=0.85, P=0.07, P=0.95). The compound secretion rate of total phosphorus in saliva of submandibular gland remained unchanged(P=0.066), while the secretion rate of K+, Na+, Cl-, Ca2+, total protein and α-amylase significantly increased(P < 0.01). The compound secretion rate of K+, Na+, Cl-, Ca2+, total protein and total phosphorus and α-amylase in parotid gland saliva increased(P < 0.01). The concentrations of Na+, Cl-, K+, total phosphorus, total protein and α-amylase in parotid were higher than those in submandibular gland (P < 0.01), and the concentration of Ca2+ in submandibular gland saliva was significantly higher than that in parotid (P < 0.001).
CONCLUSIONS: The response of parotid to acid stimulation is stronger, and the secretion of submandibular gland is more stable. Acid stimulation significantly influences the concentrations of electrolytes in saliva, and the composited secretion rate is an evaluation index to reflect both flow rate and composition concentration of saliva. The parotid gland plays an important role in the secretion of total protein, total phosphorus and α-amylase in saliva, and the submandibular gland is the main source of Ca2+ in saliva.

Steroid hormone test for saliva was a promising area of research, however the impact of different collection methods on salivary steroids was underexplored so far. This study was designed to compare the effects of different collection methods (unstimulated or stimulated by chewing paraffin, forepart or midstream) on salivary flow rate, concentrations and secretion rates of steroids in saliva.
Whole-saliva samples were collected from 10 systemically and orally healthy participants, whose forepart and midstream segments of saliva were collected under unstimulated and stimulated conditions, with the salivary flow rate of each sample recorded. The concentrations and secretion rates of salivary steroids including testosterone, dehydroepiandrosterone (DHEA) and progesterone were measured by ELISA, with the multiple of change calculated.
The results indicated mechanical stimulation used in collection of saliva samples could affect concentrations and secretion rates of steroids, whereas forepart and midstream segments had little differences in levels of salivary steroids, which effects could be partly influenced by individual specificity. The asynchronism in change of secretion rate of steroids with that of salivary flow rate might play an important role during this course.
Based on these findings, we suggested to use the same collection method throughout one analytical study on salivary steroids or in longitudinal observations to ensure the comparability of the saliva samples collected.