Natural products for the management of xerostomia: a randomized, double-blinded, placebo-controlled clinical trial

Is There More to Olive Oil than Healthy Lipids?

The Mediterranean diet is a healthy dietary pattern whose main characteristic is olive oil consumption. The potential health benefits of olive oil have been extensively investigated and the present review provides the more recent clinical evidence supporting the positive impact of olive oil intake on human health. PubMed (n = 227) and Scopus (n = 308) databases were searched for published clinical studies in English over the past six years (October 2016 to December 2022), following key word searches of "olive oil" and "health". Major findings associated olive oil with antioxidant and anti-inflammatory effects, improvement in endothelial function and lipid profile, prevention of obesity, diabetes, cardiovascular and neurodegenerative diseases, and modulation of the gut microbiota. These benefits are attributed to the nutritional composition of olive oil, which has a high content of monounsaturated fatty acids (MUFA) (oleic acid in particular) and minor compounds such as polyphenols (oleuropein and hydroxytyrosol). Although additional research continues to be required, the more recently generated evidence supports the potential of olive oil to contribute beneficially to health and to the prevention and management of a variety of non-communicable diseases, as a consequence of the synergism between its components' complexity.

A Review of the Role of Natural Products as Treatment Approaches for Xerostomia

Xerostomia, commonly known as dry mouth, is a widespread oral health malfunction characterized by decreased salivary flow. This condition results in discomfort, impaired speech and mastication, dysphagia, heightened susceptibility to oral infections, and ultimately, a diminished oral health-related quality of life. The etiology of xerostomia is multifaceted, with primary causes encompassing the use of xerostomic medications, radiation therapy to the head and neck, and systemic diseases such as Sjögren's syndrome. Consequently, there is a growing interest in devising management strategies to address this oral health issue, which presents significant challenges due to the intricate nature of saliva. Historically, natural products have served medicinal purposes, and in contemporary pharmaceutical research and development, they continue to play a crucial role, including the treatment of xerostomia. In this context, the present review aims to provide an overview of the current state of knowledge regarding natural compounds and extracts for xerostomia treatment, paving the way for developing novel therapeutic strategies for this common oral health issue.

Xerostomia: From Pharmacological Treatments to Traditional Medicine-An Overview on the Possible Clinical Management and Prevention Using Systemic Approaches

Despite high incidence rates and severe complications, the management of xerostomia lacks clinical guidelines. The aim of this overview was to summarize the clinical experience derived from the last 10 years of treatments and prevention using systemic compounds. Results showed that the cytoprotective drug amifostine, and its antioxidant agents, are the most discussed as preventive agents of xerostomia in head and neck cancer (HNC) patients. In the presence of the disease, the pharmacological treatments have been mainly directed to stimulate secretion of the damaged salivary glands, or to counteract a decreased capacity of the antioxidant system, in view of an increasing of reactive oxygen species (ROS). However, the data demonstrated low ability of the drugs, together with a great number of side effects, which strongly limit their use. Concerning traditional medicine (TM), valid clinical trials are so limited that neither the efficacy nor the absence of interferences to concomitant chemical therapies can be validated. Consequently, the management of xerostomia and its devastating complications remain a very significant void in daily clinical practice.

World Workshop on Oral Medicine VIII: Development of a Core Outcome Set for Dry Mouth: A Systematic Review of Outcome Domains for Xerostomia

OBJECTIVE

The purpose of this study was to identify all outcome domains used in clinical studies of xerostomia, that is, subjective sensation of dry mouth. This study is part of the extended project "World Workshop on Oral Medicine Outcomes Initiative for the Direction of Research" to develop a core outcome set for dry mouth.

STUDY DESIGN

A systematic review was performed on MEDLINE, EMBASE, CINAHL, and Cochrane Central Register of Controlled Trials databases. All clinical and observational studies that assessed xerostomia in human participants from 2001 to 2021 were included. Information on outcome domains was extracted and mapped to the Core Outcome Measures in Effectiveness Trials taxonomy. Corresponding outcome measures were summarized.

RESULTS

From a total of 34,922 records retrieved, 688 articles involving 122,151 persons with xerostomia were included. There were 16 unique outcome domains and 166 outcome measures extracted. None of these domains or measures were consistently used across all the studies. The severity of xerostomia and physical functioning were the 2 most frequently assessed domains.

CONCLUSION

There is considerable heterogeneity in outcome domains and measures reported in clinical studies of xerostomia. This highlights the need for harmonization of dry mouth assessment to enhance comparability across studies and facilitate the synthesis of robust evidence for managing patients with xerostomia.

Effects of Fermented Lingonberry Juice Mouthwash on Salivary Parameters—A One-Year Prospective Human Intervention Study

A one-year prospective human intervention study was performed to examine the effects of fermented lingonberry juice (FLJ), used as a mouthwash for six months, on salivary parameters. A total of 25 adult participants used 10 mL of FLJ as mouthwash 30 s daily for 6 months in addition to their normal oral homecare routines. Standard oral examinations and gathering of samples were performed at the beginning of the study and after six months and one year. Resting and stimulated saliva secretion rates, resting saliva pH, and stimulated saliva buffering capacity were determined. A questionnaire of participants’ subjective sensations of mouth dryness was also recorded at each timepoint. Fermented lingonberry juice mouthwash had positive effect to all five salivary parameters and were, according to the omnibus test, statistically significant during the study period. Analysis of the subjective dry mouth sensation questionnaires revealed that symptoms of xerostomia decreased due to the use of FLJ. This study revealed that the once-a-day use of FLJ mouthwash had a beneficial, increasing effect on salivary flow rates, buffering capacity, and salivary pH. FLJ thus can be safely used as an adjunctive and beneficial therapy in oral homecare, protecting teeth and oral mucosa, including periodontium, and also relieving dry mouth symptoms.

A Stimulator of the Salivary Excretion Based on Physical Vibration of the Parotid Glands

Oral dryness causes significant health problems both functional (difficulty speaking, chewing and swallowing) and structural in teeth (increased number of infections) and oral mucosa. The main objective of this study is to show an alternative treatment to help stimulate the salivary secretion thus improving the quality of life of the patient. In this study, a salivary stimulation equipment using vibrotactile stimuli is shown. The system has been placed bilaterally in the parotid glands and assessed the efficacy of the salivary secretion by sialometry before and after the stimulation. The new proposal is capable of stimulating salivary secretion, in a significative way after 7 minutes of use, at least in the cases analyzed, and fulfills low-cost, easy-to-use, and safe technical restrictions. In this setting, this paper suggests the performance of a deep clinical trial to measure the exact efficacy of the prototype and the times and frequencies needed to state the optimal treatment depending in each case.

Antioxidant-Rich Natural Raw Materials in the Prevention and Treatment of Selected Oral Cavity and Periodontal Diseases

Antioxidant-rich natural raw materials have been used for thousands of years in traditional medicine. In the past decade, there has been increasing interest in naturotherapy, which is a practice of using products with a natural origin. Natural products can be effective in the treatment and prevention of oral and dental diseases, among others. Such raw materials used in dentistry are characterized by antioxidant, anti-inflammatory, antibacterial, antiviral, antiedematous, astringent, anticoagulant, dehydrating, vitaminizing, and-above all-regenerative properties. Reports have shown that a relationship exists between oral diseases and the qualitative and quantitative composition of the microbiota colonizing the oral cavity. This review aimed to analyze the studies focusing on the microbiome colonizing the oral cavity in the context of using natural raw materials especially herbs, plant extracts, and isolated biologically active compounds as agents in the prevention and treatment of oral and periodontal diseases such as dental caries as well as mucosal changes associated with salivary secretion disorder. The present work discusses selected plant ingredients exhibiting an antioxidant activity with potential for the treatment of selected oral cavity and periodontal diseases.

Saliva substitute mouthwash in nasopharyngeal cancer survivors with xerostomia: a randomized controlled trial

Objectives

Xerostomia is a prevalent sequelae among nasopharyngeal cancer (NPC) survivors; yet, effective treatment protocols have been elusive. This study was a prospective randomized clinical trial to compare the effects of saliva substitute mouthwash in nasopharyngeal cancer survivors with xerostomia, between two treatment arms, conducted in a tertiary center.

Materials and methods

This study measured the effects within 4 weeks in relation to summated xerostomia inventory (SXI) and unstimulated whole saliva (UWS). Patients randomized into the interventional arm were prescribed an immunologically active saliva substitute (IASS), while patients in the control arm were prescribed a non-immunologically active mouthwash as placebo.

Results

The study population consisted of 94 patients. There was a significant difference in SXI difference (p < 0.0001) and UWS difference (p < 0.0001) between control and interventional arms. No harmful side effects associated with the use of either mouthwash encountered throughout the study duration.

Conclusion

IASS mouthwash significantly reduces subjective xerostomia scores measured using SXI and improves objective measurement of salivary flow using UWS among nasopharyngeal cancer survivors with xerostomia.

Clinical relevance

IASS is significantly more effective in improving subjective and objective xerostomia measurements compared to non-immunologically active mouthwash. Additionally, this treatment is very safe, with superior side effect profiles.

Trial registration

ClinicalTrials.gov Identifier: NCT04491435

Topical pilocarpine for xerostomia in patients with head and neck cancer treated with radiotherapy

OBJECTIVE

To evaluate a pilocarpine spray as a treatment for xerostomia in patients treated with radiotherapy (RT) for head and neck cancer (HNC).

METHODS

This was a placebo-controlled, double-blind, crossover clinical trial of patients complaining of dry mouth after RT for HNC. Forty patients were randomly assigned to either placebo or pilocarpine (1.54%) spray and instructed to use three times a day for 3 months. After 1-month washout period, patients were crossed over to receive placebo or pilocarpine. The assessments were salivary flow (Stimulated Whole Saliva Flow - SWSF), xerostomia (Xerostomia Inventory - XI), and quality of life (QoL/Oral Health Impact Profile - OHIP-14), assessed at baseline, 1 hr (only SWSF), and at 1, 2, and 3 months of treatment.

RESULTS

Posttreatment SWFS was not statistically different between pilocarpine and placebo regardless of the treatment sequence (paired T test; p > .05), except for the SWFS rates at 2 months after therapy. When comparing pilocarpine with placebo in the time points, there was no significant difference (p > .05) for QoL or XI. Significant differences in improvement in QoL and xerostomia experience appeared along time for pilocarpine group.

CONCLUSION

The topical application of pilocarpine spray tested was similar to placebo on SWSF assessments in patients treated with RT for HNC.

Interventions to improve oral health of older people: A scoping review

OBJECTIVES

A range of interventions have been tested to improve oral health of older people. We performed a scoping review to map interventions' aims, outcome measures and findings, and to locate them on different levels of care.

DATA

We systematically screened for (1) controlled studies on (2) people over 65 years of age, (3) comparing at least two interventions to improve oral health. Interventions were summarized according to their aims and the employed intervention type, mapped on their level of action, and classified as primary/secondary/tertiary prevention.

SOURCES

Studies retrieved via MEDLINE, EMBASE, CINAHL.

STUDY SELECTION

Eighty-one studies (published 1997-2019, conducted mainly in high-income countries) were included. Sample sizes varied (n = 24-1987). Follow-up was 0.25-60 months. Most studies (64/81) found a statistically significant benefit of the intervention. A total of 13 different aims were identified, and a range of intervention types employed (e.g. educational interventions, professional oral healthcare, restorative treatment, fluoride application and, generally, dentifrices, mouthwashes, chewing gums/food supplements). Most studies were located on the carer/patient level (56/81 studies) or the system/policy-maker level (44/81). The majority of studies aimed for primary prevention (64/81).

CONCLUSIONS

Oral health improvement interventions are widely studied. However, study aims, methods and outcome measures are highly heterogeneous, which limits the ability for robust conclusions. Current research focusses on primary prevention on the level of patients/carers or system/policy-maker level. Future studies may want to consider interventions on dentists' level focussing on secondary prevention. These studies should rely on a core set of comprehensive, standardized set of outcome measures.

CLINICAL SIGNIFICANCE

While specific interventions seem efficacious to improve older people's oral health, the current body of evidence is neither comprehensive (significant gaps exists in relevant levels of the care process) nor comparable enough to draw robust conclusions.

Efficacy of saliva substitutes and stimulants in the treatment of dry mouth

AIMS

To evaluate the efficacy of saliva substitutes and stimulants compared to placebo in improving findings of dry mouth not caused by Sjӧgren's.

METHODS AND RESULTS

Four databases were searched (PubMed, Web of Science, Cochrane Library, and EMBASE) through March 2018. Only randomized controlled trials (RCT) using placebo interventions with dry mouth patients were included. Outcomes included salivary flow and self-reported patient improvement. The Cochrane Collaboration's tool for assessing risk of bias was used. A total of 348 references were reviewed, resulting in 7 RCTs with 257 dry mouth patients with 5 studies at high risk of bias, 1 unclear and 1 low risk being included. Topical spray of 1% malic acid increased unstimulated (Difference in Means [DM] = 0.096, 95% CI = 0.092-0.100; P < 0.001) and stimulated (DM = 0.203, 95% CI = 0.106-0.300; P < 0.001) salivary flow in 2 studies. Patients using 1% malic acid topical spray were 5.4 times more likely to report improvement compared to placebo (95% CI = 2.634-11.091; P < 0.001) in 2 studies. No significant improvements were found with other products when compared to placebo.

CONCLUSION

Use of 1% malic acid topical spray seems to improve dry mouth compared to placebo. Quality of the evidence was low due to risk of bias and imprecision.