Scent of relief: Mastic resin scent recovers salivation in chronic dry mouth patients.

BACKGROUND: Olfactory stimulation with mastic resin, derived from the Pistacia lentiscus tree, demonstrated a bona fide sialagogic effect in healthy volunteers [1]. Its main volatile compound, α-pinene, also showed this effect. The current study aimed to validate the effect of mastic resin volatiles in chronic dry mouth patients with confirmed decreased saliva secretion. METHODS: 41 chronic dry mouth patients with decreased unstimulated saliva secretion (<0.25 mL/min) were exposed to mastic resin volatiles as part of the diagnostic routine at the Saliva Clinic of Academic Centre for Dentistry Amsterdam. During their visit, dry-mouth questionnaires were conducted and samples of unstimulated whole saliva, chew-stimulated saliva, acid-stimulated saliva and mastic resin stimulated saliva were collected. Saliva flow rate, spinnbarkeit, pH, ion composition, MUC5B and MUC7 levels in all samples were analyzed. RESULTS: Salivary flow rates increased by all stimuli when compared to the baseline unstimulated saliva (P<0.001). During olfactory mastic resin stimulation, the salivary spinnbarkeit (P<0.001) and sodium concentration (P<0.01) were increased compared to unstimulated saliva. MUC5B and MUC7 levels were increased during olfactory mastic resin stimulation compared to chew-stimulated saliva (P=0.016 and P<0.001, respectively). Spinnbarkeit correlated positively with MUC5B (R=0.399, P=0.002) and MUC7 levels (R=0.375, P=0.004). Results of dry-mouth questionnaires indicated reduced posterior palate dryness shortly after olfactory mastic resin stimulation (P=0.04). CONCLUSIONS: Olfactory mastic resin stimulation increased mucous saliva secretion and reduced posterior palate dryness in a group of chronic dry mouth patients. These findings, validated in patients, underscore mastic resin scent as a beneficial and non-invasive sialagogic treatment for clinical applications.

Transdermal pilocarpine on the skin over salivary glands to increase salivation: an in vivo study.

BACKGROUND: Hyposalivation is treated using oral cholinergic drugs; however, systemic side effects occasionally lead to discontinuation of treatment. We aimed to investigate the effects of transdermal pilocarpine on the salivary gland skin on saliva secretion and safety in rats. METHODS: Pilocarpine was administered to rats orally (0.5 mg/kg) or topically on the salivary gland skin (5 mg/body). Saliva volume, the number of sweat dots, and fecal weight were measured along with pilocarpine concentration in plasma and submandibular gland tissues. RESULTS: Saliva volume significantly increased 0.5 h after oral administration and 0.5, 3, and 12 h after topical administration. Fecal weight and sweat dots increased significantly 1 h after oral administration; however, no changes were observed after topical application. The pilocarpine concentration in the submandibular gland tissues of the topical group was higher than that in the oral group at 0.5, 3, and 12 h of administration. CONCLUSIONS: Pilocarpine application to salivary gland skin persistently increased salivary volume in rats without inducing sweating or diarrhea. Transdermal pilocarpine applied to the skin over the salivary glands may be an effective and safe treatment option for hyposalivation.

Decoupling of desire and salivation over repeated chocolate consumption and the moderating role of food legalizing.

This study aimed to investigate the responses in desire and salivation during repeated chocolate consumption, and examining how these responses are influenced by a relaxed relationship with food, or 'food legalizing'. Salivation is often used as a proxy for desire, though evidence for this correlation is mixed. We hypothesized that both desire and salivation would decrease with repeated chocolate intake. Additionally, research has suggested that eating styles may affect habituation rates. We proposed that individuals with the food legalizing trait would habituate more rapidly to chocolate, providing an alternative mechanism to reward sensitivity associated with restrained eating. Fifty healthy-weight individuals participated in the study, consuming five blocks of chocolate (each 4 g, 22 calories) over trials. After the trials, participants were allowed to eat as much chocolate as they desired. The results showed that salivation was not correlated with self-reported desire over repeated chocolate consumption. While desire decreased with repeated intake and predicted ad libitum consumption, salivation increased and did not predict ad libitum consumption. Furthermore, food legalizing moderated the rate of responding in terms of the desire to eat but did not affect salivary flow. These findings suggest that salivation is not a reliable physiological measure of desire when eating chocolate. Instead, salivation appears to reflect sensitization to the sensory characteristics of chocolate and is less predictive of subsequent ad libitum chocolate consumption than self-reported desire. Lastly, having a carefree relationship with chocolate may help regulate its consumption, highlighting the potential benefits of a relaxed attitude toward food.

Age-related alteration of the involvement of CD36 for salivary secretion from the parotid gland in mice.

This in vivo mouse model study was conducted to investigate the temporal alteration of the function of CD36 in salivary secretion. CD36 was highly expressed in the parotid gland of BALB/c mice. No significant variations were shown in the CD36 levels in the 8-, 48-, and 72-week-old animals. However, pilocarpine-induced salivary secretion was reduced in an age-dependent manner, showing a significantly low level at the age of 72 weeks. Pilocarpine-induced salivary secretion was significantly reduced by pretreatment with a CD36 inhibitor at 8 and 48 weeks, but not at 72 weeks. In senescence-accelerated mice (SAM), the pilocarpine-induced salivary secretion was significantly reduced at the age of 56 weeks, and a significantly lower amount of CD36 was demonstrated in the parotid gland, compared with the control. These results suggest that the involvement of parotid CD36 in mouse salivary secretion is altered with age.

Intraoral Acupuncture for Sialorrhea in Stroke Patients: a Study Protocol for a Randomized Controlled Trial.

Importance: Post-stroke sialorrhea (PSS) refers to excessive saliva flowing out the lip border after a stroke. PSS negatively affects patient self-image and social communication and may lead to depression. Limited evidence supports the link between excessive salivation and PSS. No large-scale, strictly controlled randomized controlled trials have shown the effectiveness of acupuncture in treating PSS patients. Objective: We aim to compare the effects of intraoral and sham acupuncture in PSS patients and explore relationships among salivation and drooling severity and frequency and swallowing function in stroke patients. Design: Clinical study protocol, SPIRIT compliant. Setting: Prospective, single-center, randomized, and sham-controlled trial. Population: We will recruit 106 PSS patients to receive 4-week intraoral or sham acupuncture. Additionally, 53 stroke patients without PSS will undergo a conventional 4-week treatment program to compare salivation between PSS and non-PSS patients. Exposures: Intraoral or sham acupuncture. Main Outcomes and Measures: The main evaluation index will be the 3-minute saliva weight (3MSW), comparing changes in 3MSW from baseline to weeks 4 and 8. Secondary assessment indices will include the "Drooling Severity and Frequency Scale" and "Functional Oral Intake Scale." Results: The results from this study will be published in peer-reviewed journals. Conclusion: Comparing effects of intraoral and sham acupuncture in PSS patients, this study may contribute important evidence for future PSS treatment and provide valuable insights into whether salivation issues in stroke patients are attributed to heightened salivary secretion or dysphagia.

Impact of salivary flow inhibition on masticatory behaviours in healthy individuals.

BACKGROUND: It remains unclear how the salivary flow and the fat content of food affect bolus formation during mastication. OBJECTIVES: We aimed to clarify: (1) how hyposalivation affects jaw-closing and hyoid-elevating muscle activities in bolus formation, and (2) if the effect of hyposalivation on muscle activity depends on the fat content of food. METHODS: Eighteen healthy male volunteers were instructed to freely ingest four test foods: Plain, Fat without seasoning, Fat with seasoning, and Soft rice crackers. Masseter and suprahyoid electromyographic activities were recorded before and 30 min after the administration of atropine sulfate, a muscarinic receptor antagonist that induces hyposalivation. RESULTS: Hyposalivation extended the masticatory duration significantly in all the test foods except Fat with seasoning. Masticatory cycle time was significantly longer with vs without hyposalivation for the Soft (p = .011). Suprahyoid activity/cycle was significantly greater with vs without hyposalivation (p = .013). Masticatory cycle time was significantly longer at the late stage with vs without hyposalivation for the Soft (p < .001). Suprahyoid activity/cycle was significantly greater at the middle (p = .045) and late stages (p = .002) with vs without hyposalivation for the Soft and greater at the late stage with vs without hyposalivation for the Plain (p = .043). Changes in masticatory cycle time and suprahyoid activity/cycle for these foods had significantly positive relationship (p < .001). CONCLUSION: Hyposalivation-induced changes in masticatory behaviours resulted from the middle and late stage suprahyoid activity. Fat content and seasoning compensate for salivary flow inhibition.

Prospective study on health-related quality of life, oral mucositis and oral health on during treatment of head and neck cancer.

BACKGROUND: Few studies have examined health related Quality of Life (HR-QoL) during the treatment of head and neck cancer (HNC) with even fewer focusing on the impact of oral mucositis (OM) on HR-QoL. Studies performed during treatment of HNC makes it possible to follow fluctuations in HR-QoL, OM and other treatment related side effects. The aim was to prospectively analyze HR-QoL, changes in clinical variables and the impact of OM on HR-QoL during HNC treatment. MATERIALS AND METHODS: Patients were recruited before commencing curative cancer treatment and were given professional oral care weekly during oncologic treatment. HR-QoL was reported before, during (week 2, 4 and 6) and three months after treatment using the EORTC Quality of Life questionnaires C30 and H&N35 and the stimulated whole salivary secretion rate was determined at the same time-points. OM (erythema and ulceration) was registered using the Oral Mucositis Assessment Scale (OMAS), at baseline, weekly during treatment and post treatment. Differences in HR-QoL between different timepoints were analyzed. To analyze the impact of OM on HR-QoL the patients were categorized into two groups: no/mild OM (OMAS ulceration score 0-1) or severe OM (OMAS ulceration score ≥ 2) and HR-QoL was compared between the two OM groups at three timepoints during treatment. RESULTS: Fifty-seven patients (43 men, 14 women), with a mean age of 58 years were included. Patients reported progressively impaired HR-QoL, with peak issues noted at weeks 4 and 6, particularly in social eating, senses, appetite loss, sticky saliva, and decreasing salivary secretion rates were determined. Patients with severe OM reported worse HR-QoL compared to those with no/mild OM. Persistent problems 3 months post treatment were appetite loss, dry mouth, senses (smell and taste) and problems with social eating. CONCLUSION: Patients experienced exacerbated symptoms and problems weeks 4 and 6 of oncological treatment, especially among those with severe OM, stressing the importance of clinically monitoring the patients to reduce and alleviate their symptoms. Persistent problems three months post treatment are likely associated with the reduced salivary secretion rate indicating that patients should be monitored also after completed oncological treatment.

Effect of lozenge surface texture, taste and acidity on salivary flow rate: A crossover preclinical trial in healthy subjects.

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.

Immediate effects of photobiomodulation on saliva production. / Efeitos imediatos da fotobiomodulação na produção de saliva.

PURPOSE: To verify the immediate effects of photobiomodulation on the production of salivary flow and the correlation of demographic, anthropometric and medication use data. METHODS: The study included 100 healthy individuals, aged between 18 and 76 years (mean 27.2 years), randomly split into an experimental group and a placebo group. Assessments of anthropometric measurements, self-perception of saliva production and sialometry were performed. Next, LASER irradiation was carried out at an infrared wavelength (808 nanometers) with 100 milliwatts (mw) of power at five intraoral points: on the sublingual glands and bilaterally on the submandibular and parotid glands, at doses of 9, 18 and 24 joules (J). Sialometry was repeated after each application. The control group received the same procedures with placebo equipment. RESULTS: There was a statistical association in the self-perception of reduced saliva in the experimental group for the 24J dose and in sialometry and in the reduction in salivary flow for the 18J and 24J doses and an increase to 9J, in both groups. There was no association when comparing the experimental and placebo groups. Multiple multinomial regression analysis revealed that the reduction or increase in salivary flow is independent of demographic, anthropometric and medication use variables. CONCLUSION: The bioinhibitory action of photobiomodulation on healthy salivary glands occurred at a dose of 18J and 24J, while the biostimulant action happened at a dose of 9J, regardless of demographic, anthropometric variables and medication use. The self-perception of reduced salivary flow occurred at 24J.

OBJETIVO: Verificar os efeitos imediatos da fotobiomodulação na produção do fluxo salivar e a correlação dos dados demográficos, antropométricos e de uso de medicamentos. MÉTODO: Participaram do estudo 100 indivíduos saudáveis, com idade entre 18 e 76 anos (média 27,2 anos), divididos de forma randomizada em grupo experimental e grupo placebo. Foram realizadas as avaliações das medidas antropométricas, autopercepção da produção de saliva e a sialometria. Na sequência, realizou-se a irradiação do LASER no comprimento de onda infravermelho (808 nanômetros) com 100 miliwatts (mw) de potência em cinco pontos intraorais: nas glândulas sublingual e bilateralmente nas submandibulares e parótidas, nas doses 9, 18 e 24 joules (J). A sialometria foi repetida após cada aplicação. O grupo controle recebeu os mesmos procedimentos com equipamento placebo. RESULTADOS: Houve associação estatística na autopercepção de redução da saliva no grupo experimental para a dose de 24J e na sialometria e na redução do fluxo salivar para as doses 18J e 24J e aumento para 9J, em ambos os grupos. Não houve associação quando comparado entre os grupos experimental e placebo. A análise de regressão multinomial múltipla revelou que a redução ou o aumento do fluxo salivar independe das variáveis demográficas, antropométricas e uso de medicamentos. CONCLUSÃO: A ação bioinibitória da fotobiomodulação sobre as glândulas salivares saudáveis ocorreu em dose de 18J e 24J, já ação bioestimulante na dose 9J, independe das variáveis demográficas, antropométricas e uso de medicamentos. A autopercepção da redução do fluxo salivar ocorreu em 24J.

Parotid hypersalivation after inferior salivatory nucleus glutamate/NMDA receptor excitation in the rat.

Although salivation is essential during eating behavior, little is known about the brainstem centers that directly control the salivary glands. With regard to the inferior salivatory nucleus (ISN), the site of origin of the parasympathetic preganglionic cell bodies that innervate the parotid glands, previous anatomical studies have located it within the rostrodorsal medullary reticular formation. However, to date there is no functional data that shows the secretory nature of the somas grouped in this region. To activate only the somas and rule out the activation of the efferent fibers from and the afferent fibers to the ISN, in exp. 1, NMDA neurotoxin was administered to the rostrodorsal medullary region and the secretion of saliva was recorded during the following hour. Results showed an increased secretion of parotid saliva but a total absence of submandibular-sublingual secretion. In exp. 2, results showed that the hypersecretion of parotid saliva after NMDA microinjection was completely blocked by the administration of atropine (a cholinergic blocker) but not after administration of dihydroergotamine plus propranolol (α and ß-adrenergic blockers, respectively). These findings suggest that the somata of the rostrodorsal medulla are secretory in nature, controlling parotid secretion via a cholinergic pathway. The data thus functionally supports the idea that these cells constitute the ISN.

A novel test for hyposalivation using a sugar cube.

BACKGROUND: Hyposalivation is a highly prevalent condition in old persons. OBJECTIVES: The aim of this study was to assess a novel tool for the diagnosis of hyposalivation using a sugar cube and to compare its reliability to other validated test methods. METHODS: Five tests were performed: unstimulated salivary flow test by draining method (USFT), oral moisture device Mucus® (MCS), sugar cube test (SCT), stimulated salivary flow test by chewing gum (CG) and Saxon test (SX). The sugar cube test consisted in measuring the time needed to disintegrate a standard-sized sugar cube N°4 (5.6 g) placed beneath the tongue. Bivariate correlation analyses were performed. ROC curve analysis and the Youden Index were used to determine the cut-off value. Sensitivity and specificity were calculated according to the determined cut-off point. RESULTS: A total of 121 participants were recruited, with an average age of 49.8 ± 18.2 years. The USFT was best correlated with the SCT. No correlation was found between SCT and the stimulated saliva tests (CG, SX) as well as the MCS test. According to the Youden index, 140 s is appropriate to diagnose hyposalivation. Sensitivity of .64 and specificity of .91 were found for SCT using USFT as gold standard. The mean subjective evaluation score of the SCT was 3.1 ± 1, significantly higher than USFT 2.6 ± 1.1 (p < .05). CONCLUSIONS: The sugar cube test proved to be a useful method for assessing unstimulated salivation, reducing test execution time and causing less participant discomfort than the gold standard unstimulated salivary flow test.

Effectiveness of atropine in managing sialorrhea: A systematic review and meta-analysis.

OBJECTIVES: To describe the efficacy of atropine in controlling salivary flow in patients with sialorrhea or drooling. MATERIALS AND METHODS: We included randomized controlled studies, quasi-randomized trials, case reports, clinical trials, systematic reviews, and meta-analyses assessing the use of atropine in patients with sialorrhea or drooling. The endpoints were reduction in salivary flow rate, amount of saliva secreted, reduction in clinical symptoms of sialorrhea, death rattle intensity, or reduction in drooling intensity as measured by an objective scale such as the drooling intensity scale. RESULTS: A total of 56 studies with 2,378 patients were included in the systematic review. The underlying disease states included brain injury, amyotrophic lateral sclerosis, cerebral palsy, clozapine- and perphenazine-induced sialorrhea, Parkinson's disease, and terminal illness. The routes of atropine administration included sublingual, intravenous, subcutaneous, oral tablet or solution, and direct injection of atropine into parotid glands or at the base of the tongue. The generalized estimated equation regression models showed that sublingual administration is superior to oral and subcutaneous routes. CONCLUSION: Atropine is efficacious in managing sialorrhea in most disease states. Sublingual administration of atropine is superior to other routes of administration in reducing salivary flow in patients with sialorrhea.

Evaluation of photobiomodulation in the salivary production of patients with hyposalivation induced by antihypertensive drugs - A blind, randomized, controlled clinical trial.

BACKGROUND: Arterial hypertension is a systemic condition that affects about 35% of the world population. The drugs that are used for its control can produce hyposalivation. This work evaluated the effect of photobiomodulation on salivary flow rate, salivary pH, total protein concentration, and calcium concentration in individuals using antihypertensive medications. MATERIAL AND METHODS: 41 subjects were randomly allocated in one of two groups: control (placebo) and photobiomodulation. The subjects had their salivary glands (20 sites) irradiated with a laser emitting at 808 nm, 4J/site once a week for 4 weeks and had their salivary flow measured before and after the whole treatment. RESULTS: The intragroup analysis (before and after treatment) shows a significant difference for both non-stimulated and stimulated salivary flow in the photobiomodulation group (p = 0.0007 and p = 0.0001, respectively). Comparing the placebo with the photobiomodulation group, significant differences were found for both non-stimulated (p = 0.0441) and stimulated salivary flow (p = 0.0441) after the treatment. No significant differences were found in pH, total protein concentration, calcium concentration. CONCLUSION: Despite the usage of drugs that influence the nervous system and typically result in a reduction of saliva production, photobiomodulation demonstrated a remarkable ability to enhance saliva production by a significant 75%.

Radiation-induced Xerostomia is Related to Stem Cell Dose-dependent Reduction of Saliva Production.

PURPOSE: Previous studies have shown that the mean dose to the parotid gland stem cell rich regions (Dmean,SCR) is the strongest dosimetric predictor for the risk of patient-reported daytime xerostomia. This study aimed to test whether the relationship between patient-reported xerostomia and Dmean,SCR is explained by a dose-dependent reduction of saliva production. METHODS AND MATERIALS: In 570 patients with head and neck cancer treated with definitive radiation therapy (RT), flow from the parotid (FLOWPAR) and submandibular/sublingual (FLOWSMSL) glands, and patient-reported daytime (XERDAY) and nighttime (XERNIGHT) xerostomia were prospectively measured before, at 6 months, and 12 months after RT. Using linear mixed effect models, the relationship of the mean dose to the parotid glands (Dmean,par), Dmean,SCR, non-SCR parotid gland tissue (Dmean,non-SCR), submandibular glands (Dmean,sub), and oral cavity (Dmean,oral) with salivary flow and xerostomia was analyzed while correcting for known confounders. RESULTS: Dmean,SCR proved to be responsible for the effect of Dmean,par on FLOWPAR (P ≤ .03), while Dmean,non-SCR did not affect FLOWPAR (P ≥ .11). To illustrate, increasing Dmean,SCR by 10 Gy at a fixed Dmean,non-SCR reduced FLOWPAR by 0.02 mL/min (25%) after RT. However, if the opposite happened, no change in FLOWPAR was observed (0.00 mL/min [4%]). As expected, Dmean,sub was significantly associated with FLOWSMSL (P < .001). For example, increasing Dmean,sub by 10 Gy reduced FLOWSMSL by 0.07 mL/min (26%) after RT. Xerostomia scores were also affected by dose to the salivary glands. Dmean,SCR and Dmean,oral were associated with higher XERDAY scores (P ≤ .05), while Dmean,sub increased XERNIGHT scores (P = .01). For example, an increase of 10 Gy in Dmean,SCR raised XERDAY scores by 2.13 points (5%) after RT, while an additional 10 Gy in Dmean,subs increased XERNIGHT scores by 2.20 points (6%) after RT. Salivary flow was not only associated with radiation dose, but also with xerostomia scores in line with the salivary glands' functions; ie, FLOWPAR only influenced XERDAY (P < .001, 10.92 points lower XERDAY per 1 mL/min saliva), while FLOWSMSL affected XERDAY and XERNIGHT (P ≤ .004, 6.69 and 5.74 points lower XERDAY and XERNIGHT, respectively, per 1 mL/min saliva). Therefore, the observed relationships between dose and xerostomia were corrected for salivary flow. As hypothesized, Dmean,SCR only increased XERDAY scores via reducing FLOWPAR, whereas the effects of Dmean,oral on XERDAY and Dmean,sub on XERNIGHT were independent of salivary flow. CONCLUSIONS: Higher SCR region dose reduced parotid gland saliva production, subsequently resulting in higher daytime xerostomia scores. Consequently, this study supports the clinical implementation of stem cell sparing RT to preserve salivary flow with the aim of reducing the risk of xerostomia.

In females, salivary secretion was significantly lower in patients with severe reflux esophagitis than in healthy controls.

BACKGROUND: The salivary secretion in patients with mild reflux esophagitis (RE) and non-erosive reflux disease is significantly lower in females, but not in males. However, sex differences in salivary secretion in patients with severe RE remain unknown. Therefore, the present study investigated sex differences in saliva secretion in patients with severe RE. METHODS: Subjects consisted of 23 male patients with severe RE, 24 male healthy controls (HCs), 26 female patients with severe RE, and 25 female HCs. Saliva secretion was assessed as follows: each patient chewed sugarless gum for 3 min prior to endoscopy, and the amount and pH of saliva secreted before and after acid loading as an index of the acid-buffering capacity were measured. RESULTS: In males, no significant differences were observed in the amount of saliva secretion, salivary pH, or the acid-buffering capacity between severe RE patients and HCs. In females, the amount of saliva secretion (severe RE: 2.4 [1.8-4.1], HCs: 5.3 [3.4-7.5], p = 0.0017), salivary pH (severe RE: 7.0 [6.7-7.3], HCs: 7.2 [7.1-7.3], p = 0.0455), and the acid-buffering capacity (severe RE: 5.9 [5.3-6.2], HCs: 6.2 [6.1-6.5], p = 0.0024) were significantly lower in severe RE patients than in HCs. CONCLUSION: Among females, the salivary secretion was significantly lower in severe RE patients than in HCs. This reduction in salivary secretion may contribute to the pathophysiology of severe RE in females.

Whole unstimulated salivary flow rate decreases during acute stressful condition.

OBJECTIVE: To examine the influence of acute stress on salivary flow using a validated stressor paradigm. STUDY DESIGN: This uniform crossover study consisted of 40 healthy adults who underwent the Trier Social Stress Test, consisting of a 5-minute mental arithmetic task (MAT), and a nonstressful task (NST), consisting of a 5-minute free speech task. The order of the tasks was counterbalanced and unstimulated whole saliva (UWS) was measured in 2 groups of 20 participants during each 5-minute task condition, with a 10-minute washout period between tasks. At baseline, mathematical ability was self-reported and psychological distress was measured using the Symptom Checklist-90-Revised. Heart rate (HR) and breathing rate (BR) were recorded during each task. RESULTS: Age, sex, HR, BR, and psychological distress were similar between groups at baseline (P > .05). During the MAT, HR increased significantly and mean UWS flow rate decreased significantly compared with the NST (P < .001). CONCLUSIONS: An acute psychobiological stressor task was associated with a rapid decrease in salivary flow in adults. Thus, stress can contribute to reduced salivary flow and should be considered as a factor during the diagnostic workup of patients who complain of a dry mouth.

Use of the modified Schirmer test to measure salivary gland hypofunction/hyposalivation: Systematic review and meta-analysis.

Although dry mouth is a relatively common condition, salivary flow is not routinely measured in dental clinical practice. Moreover, existing data regarding the use of the modified Schirmer test (MST) for the screening of dry mouth has not been summarized. This systematic review and meta-analysis, conducted in accordance with the PRISMA guidelines, aimed to determine whether the modified Schirmer test can be used to identify dry mouth. The databases of PubMed, Scopus, ScienceDirect, and CENTRAL (CRD42023393843) were systematically searched to retrieve articles published until 9th November 2023. Among the 343 original articles retrieved, six met the inclusion criteria. A total of 1150 patients, comprising 710 (61.7%) women and 440 (38.3%) men (mean age, 47.1 ± 7.3 years), were included. The meta-analysis revealed a weak correlation coefficient of r ¯ $\bar{r}$  = 0.42 (95% Cl: 0.29-0.55) between MST and the unstimulated salivary flow rate. Therefore, while the MST might offer a simple and accessible alternative for initial screening in the future, especially in non-specialized settings, its variability in sensitivity and specificity, along with an actual lack of standardization, necessitates cautious interpretation. Further studies are necessary before recommending the test in clinical routine.

Dental care professionals' awareness of oral dryness and its clinical management: a questionnaire-based study.

BACKGROUND: Despite the high prevalence of oral dryness and awareness of its complications, there is limited research on the clinical management of patients with oral dryness in general dental care. PURPOSE: To (1) describe and compare awareness among dental care professionals regarding saliva functions, potential causes and complications of oral dryness, and patient management (2) Investigate if the length of professional experience influences these aspects. METHODS: A digital self-administrated survey was sent to 2668 dental care professionals working in the general dental care, Public Dental Service, in Sweden. Twelve dental care professionals reviewed the questionnaire prior to its distribution. The questionnaire comprised 32 questions about patient management, awareness of saliva functions, causes and complications of oral dryness, and self-assessment queries. RESULTS: The response rate was 18.6% (241 dentists and 257 dental hygienists). Older adults (65+) were asked more often about dry mouth (93.0%) compared to those aged 18-23 years (50.0%) and those under 18 years (24.9%). Dental hygienists encountered individuals with oral dryness more frequently (61.1%) than dentists (48.5%) (p < 0.01), and more often asked individuals in the age groups 18-23 years (p = 0.003), 24-40 years (p = 0.045), and 41-65 years (p = 0.031) about dry mouth. A higher proportion of dental hygienists (88.3%) than dentists (51.0%) had measured salivary secretion rate, (p < 0.001) and more often suggested preventive dental care 3-4 times a year, (42.5% vs. 30.5%) (p < 0.007). Dentists had a higher awareness of saliva functions, while dental hygienists had a higher awareness about causes and complications of oral dryness. Higher proportions of dentists and dental hygienists with over 10 years of professional experience had measured salivary secretion rate (69.1% vs. 95.7%) compared to their counterparts with less than 10 years of professional experience (35.9% vs. 79.5%) (p < 0.001 for both). CONCLUSION: Compared to dentists, dental hygienists were more attentive to patients with oral dryness as they encountered these individuals more often, asked more age-groups, suggested frequent preventive measures, and had higher awareness of the causes and complications of oral dryness. Length of professional experience could improve both the management of patients with oral dryness and awareness of its causes, particularly for dental hygienists.

Salivary Electrostimulation in the Treatment of Radiation Therapy-Induced Xerostomia (LEONIDAS-2): A Multicenter, Randomized, Double-Masked, Sham-Controlled, Phase 3 Trial.

PURPOSE: Radiation therapy-induced xerostomia significantly affects quality of life in head and neck cancer survivors. Neuro-electrostimulation of the salivary glands may safely increase natural salivation and reduce dry mouth symptoms. METHODS AND MATERIALS: This multicenter, double-masked, randomized, sham-controlled clinical trial assessed the long-term effects of a commercially available intraoral neuro-electrostimulating device in lessening xerostomia symptoms, increasing salivary flow, and improving quality of life in individuals with radiation therapy-induced xerostomia. Using a computer-generated randomization list, participants were assigned (1:1) to an active intraoral custom-made removable electrostimulating device or a sham device to be used for 12 months. The primary outcome was the proportion of patients reporting a 30% improvement on the xerostomia visual analog scale at 12 months. A number of secondary and exploratory outcomes were also assessed through validated measurements (sialometry and visual analog scale) and quality-of-life questionnaires (EORTC QLQ-H&N35, OH-QoL16, and SF-36). RESULTS: As per protocol, 86 participants were recruited. Intention-to-treat analyses showed no statistical evidence of a difference between the study groups with respect to the primary outcome or for any of the secondary clinical or quality-of-life outcomes. Exploratory analyses showed a statistically significant difference in the changes over time of the dry mouth subscale score of the EORTC QLQ-H&N35 in favor of the active intervention. CONCLUSIONS: LEONIDAS-2 did not meet the primary and secondary outcomes.

Factors Associated with Hyposalivation in Brazilian Adults

ABSTRACT Objective: To determine the occurrence of hyposalivation in Brazilian adults and its association with individual determinants, such as the use of medications, systemic conditions, smoking, and alcohol consumption. Material and Methods: A cross-sectional study with 402 adults was developed. Information was collected on sociodemographic and general health characteristics, and sialometry was performed with stimulated salivary flow. It indicated low salivary flow when ≤ 0.7 mL/min. Bivariate and multivariate analyses were conducted using a decision tree (p<0.05). Results: The sample was comprised predominantly of women (68.2%) aged ≤ 29 years (25.4%). Most participants did not use medication (56.7%). Among systemic diseases, the most cited was hypertension (25.1%). More than a third of the participants presented hyposalivation (40.3%), being associated with the following variables: age between 50 to 59 years (p=0.011), female sex (p<0.001), menopause (p=0.001), use of alcohol (p=0.033), systemic disease (p=0.002) and medication use (p<0.001). In multivariate analysis, in addition to sex (p<0.001) and hypertension (p=0.005), an association was also found between hyposalivation and diabetes (p=0.014). Conclusion: Factors associated with hyposalivation in adults were sex and the presence of hypertension or diabetes.