BACKGROUND: The complex nature of xerostomia prevents the establishment of a definite cure. Recently, research has pivoted towards stem cell transplantation for glandular reconstruction. The aim of this study is to provide an updated review of the existing research, to highlight the encountered challenges and research pathways, potentially enhancing the therapeutic applications of stem cell transplantation.
METHODS: This is a systematic review according to PRISMA guidelines, using the following databases: PubMed (PMC), PMC Europe, Scopus, Medline, Research Gate, Elsevier. The main question was whether stem cell therapies can contribute to the treatment of xerostomia.
RESULTS: 19 of 226 publications met the criteria for this review, including \'in vivo\', \'in vitro\' studies and clinical trials. All 19 studies described thoroughly the stem cell source and the transplantation method, and documented results based on analytical and statistical methods of confirmation. Data show that the various sources of stem cells play a significant role, with bone marrow or adipose tissue-derived pluripotent blasts being the most utilized. Human transplants in mice have also been accepted and reversed hyposalivation. The effects have been beneficial especially in models undergone radiotherapy (IR) or exhibit Sjogren Syndrome-like symptoms (SS), suggesting that with appropriate treatment and enrichment techniques, stem cell transplantation seems effective regardless of the cause of the disorder. Extracts and co-cultures of gland and stem cells also seem to improve gland function.
CONCLUSIONS: Although in its initial stages, the use of stem cells seems to be a promising therapy to alleviate xerostomia regardless of its cause.

OBJECTIVE: Head and Neck Cancer (HNC) patients receiving radiotherapy (RT) often suffer from xerostomia and/or hyposalivation. As saliva plays an important antimicrobial and cleansing roles, these patients are at higher risks of opportunistic infections. This narrative review aims to provide an overview of current evidence on oral Candida colonisation and infection in these patients.
METHODS: A literature review of clinical studies on oral Candida colonisation and candidiasis in HNC patients receiving radiotherapy/chemoradiotherapy was conducted.
RESULTS: Many clinical studies found high levels of Candida colonisation and a substantial proportion of post-RT HNC patients suffering from oropharyngeal candidiasis (OPC). Importantly, oral Candida could be a reservoir for life-threatening systemic infection in immunocompromised patients. The rising prevalence of non-albicans Candida species and drug-resistant infections has made identification of Candida species and antifungal susceptibility more important. Recent advances in oral microbiome and its interactions with Candida are discussed. This review also offers perspectives on limitations of current evidence and suggestions for future research.
CONCLUSIONS: Further research to better understand Candida carriage, microbiome, OPC, and xerostomia/hyposalivation post-RT would aid in devising a more comprehensive long-term management plan and novel therapeutic approaches for HNC patients to achieve the full benefits of RT while minimising side effects.

Xerostomia, commonly known as dry mouth, presents a significant challenge for individuals wearing complete dentures, affecting their oral health and quality of life. This review explores the relationship between saliva and complete dentures, highlighting the varied management strategies for xerostomia. Saliva plays a critical role in denture retention, lubrication, and oral environment buffering. Complete denture wearers often experience reduced salivary flow, aggravating symptoms of xerostomia. Various management approaches are discussed, including general measures such as hydration and salivary stimulation techniques which aim to boost saliva production naturally. The use of salivary substitutes provides artificial lubrication and moisture to alleviate dry mouth discomfort. Oral lubricating devices, such as sprays, gels, and lozenges, offer relief by mimicking saliva\'s lubricating properties, thereby improving denture stability and comfort. This review addresses the etiology of xerostomia in complete denture wearers and explores preventive measures to reduce its impact. A comprehensive approach has been discussed for the management of xerostomia which will help to improve the oral health and well-being of complete denture wearers experiencing dry mouth.

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.

OBJECTIVE: Radiotherapy is one of the main strategies used in the treatment of cancer patients and it can cause early or late xerostomia and/or hyposalivation. Therapeutic management of xerostomia includes oral hygiene, sialogenic agents among others.
METHODS: This study reviews the use of extra-oral salivary glands photobiomodulation in treating xerostomia and/or hyposalivation after radiotherapy and performs a meta-analysis of this data.
RESULTS: After a broad search of the literature, eight clinical studies were selected.
CONCLUSIONS: In a safe way, the studies found that extra-oral stimulation of the salivary glands has benefits in the hyposalivation and changes in salivary flow resulting from lesions by radiotherapy. A meta-analysis found significant values in pain comparing the pre- and post-treatment moments (MD - 3.02, I2 95%, IC - 5.56; - 0.48) and for stimulated salivary flow at 30 days after the end of radiotherapy (MD 2.90, I2 95%, IC 1.96; 3.84).
CONCLUSIONS: The most promising parameters comprise wavelengths between 630 and 830 nm, radiant exposure from 2 to 10 J/cm2, two-to-three times a week, before the radiotherapy damage, and homogeneously in the glands. Therefore, Light-Emitting Diode (LED) stimulation of larger areas than the punctual stimulation of small millimeters of the Low-Level Laser Therapy (LLLT) appears to be promising.

Radiation-induced dry mouth negatively impacts patients\' oral health and quality of life. Currently, evidence-based recommendation for non-pharmacologic interventions is still lacking. This study aimed to systematically review clinical trials evaluating the efficacy of non-pharmacologic interventions in cancer patients with radiation-induced dry mouth.
Randomized controlled trials from 2000 were searched from 4 databases, including MEDLINE, Cochrane, Embase via OVID, and SCOPUS, up to December 16th, 2022 (PROSPERO registration CRD42022378405). The risk of bias was assessed using the revised Cochrane risk of bias assessment tool.
Twenty-one studies were included: 11 on artificial saliva, 4 on electrical nerve stimulation (TENS), 2 on acupuncture, and one study each on low-level laser therapy, stem cells, chewing gum, and probiotics. Overall bias was low, medium, and high in 33%, 48%, and 19% of the studies, respectively. Certain artificial saliva products and TENS were shown to improve dry mouth symptoms and salivary flow rate (SFR). One study showed that stem cell transplantation significantly increased SFR.
The evidence suggested that certain artificial saliva products and TENS are promising management. However, the evidence was still limited due to heterogeneity of interventions and outcome measurements. Thus, future studies using standard measurements and long-term follow-up are warranted.

In strict accordance with PRISMA 2020 guidelines, our research team conducted a comprehensive systematic literature review (SLR) to explore the treatment and preventive strategies for Sjögren\'s Syndrome (SS). Leveraging a meticulous search strategy, we scoured reputable databases such as PubMed, PubMed Central, Google Scholar, Web of Science, and The Cochrane Library. Our analysis zeroed in on 10 seminal articles that met our stringent inclusion criteria, providing a holistic view of the existing treatment landscape for SS, along with emerging diagnostic tools and associated biomarkers indicative of lymphoma risk. From a clinical standpoint, our findings unequivocally highlight the detrimental effects of SS on patients\' overall well-being. Of particular interest is the growing body of evidence that underscores the effectiveness of natural remedies and over-the-counter supplements rich in antioxidants as viable therapeutic interventions. Contrary to expectations, no single laboratory marker emerged as highly sensitive for the diagnosis of SS. On a promising note, dental implants have been demonstrated to offer lasting benefits with minimal side effects, emphasizing their potential utility in enhancing the oral health of individuals affected by SS. Given the evolving nature of treatment approaches for SS, our review strongly calls for further investigations. Such research endeavors are imperative for validating the effectiveness of these treatment options, whether they serve as primary or preventive care solutions, with the overarching aim of improving the quality of oral health among those suffering from SS.

Xerostomia and hyposalivation are highly prevalent conditions in old age, particularly among multimorbid elders, and are often attributed to the use of multiple medications. These conditions negatively affect oral functions, such as chewing, swallowing, speech, and taste. Additionally, the lack of lubrication of the oral mucosa frequently leads to super-infections with candida. Denture retention and comfort may also be compromised. The risk of dental caries and erosion of natural teeth increases since saliva, which is essential for repairing initial lesions in tooth structures, is insufficient. The dry sensation in the mouth also impacts the emotional and social well-being of elderly individuals. Patients experiencing xerostomia often avoid certain foods that are uncomfortable or difficult to consume. However, some foods may alleviate the symptoms or even stimulate salivation. This review discusses the limited available evidence on nutritional advice for patients with xerostomia and aims to provide insight into the patient\'s perspective while offering clinical recommendations. Future studies should focus on investigating the nutritional intake of individuals suffering from xerostomia or hyposalivation in order to ensure oral health comfort, prevent malnutrition, and minimize the impact on their quality of life.

BACKGROUND: Several systemic conditions can result in distinct degrees of salivary gland damage and consequent hypofunction. The development of successful management schemes is highly challenging due to the complexity of saliva. This study aimed to systematically map the literature on the physical stimulation of salivary glands for hyposalivation management and the response of individuals according to different systemic conditions causing salivary impairment.
METHODS: A systematic search in the literature was performed. Two reviewers independently selected clinical trials, randomized or not, that used physical stimulation to treat hyposalivation caused by systemic conditions. Studies evaluating healthy subjects without hyposalivation were included as controls. Single-arm clinical studies or case series were also included for protocol mapping (PRISMA extension for scoping reviews).
RESULTS: Out of 24 included studies, 10 evaluated healthy subjects, from which 9 tested transcutaneous electrical nerve stimulation (TENS) and 1 tested acupuncture and electroacupuncture. Fourteen studies evaluated individuals with hyposalivation: 6 applied TENS, 6 applied low-level laser therapy (LLLT), and 2 applied acupuncture, carried out in post-chemotherapy, medication use, postmenopausal women, hemodialysis patients, smokers, diabetics, Sjögren\'s syndrome (SS). All showed increased salivation after treatment, except for two LLLT studies in individuals with SS.
CONCLUSIONS: Among the different patient groups, individuals with Sjögren\'s syndrome (SS) exhibited the poorest responses, while those with medication-induced hyposalivation demonstrated the most favorable treatment outcomes, independently of the management strategy for saliva stimulation. It means that physical stimulation of salivary glands holds promise as an alternative for managing hyposalivation in cases of reversible gland damage. However, to make informed decisions in current practice, it is necessary to conduct new well-designed randomized clinical trials with appropriate methodologies.

BACKGROUND: Obstructive sleep apnoea (OSA) is a highly prevalent problem with significant consequences. Continuous positive airway pressure (CPAP) and oral mandibular advancement device (MAD) are considered the standard treatments for OSA. Patients may experience self-reported oral moistening disorders (OMDs) (i.e. xerostomia or drooling) at the beginning, throughout and after treatment. This affects oral health, quality of life and treatment effectiveness. The exact nature of the associations between OSA and self-reported OMD is still unknown. We aimed to provide an overview of the associations between self-reported OMD on the one hand and OSA and its treatment (namely CPAP and MAD) on the other hand. In addition, we sought to determine whether OMD affects treatment adherence.
METHODS: A literature search in PubMed was performed up to 27 September 2022. Two researchers independently assessed studies for eligibility.
RESULTS: In total, 48 studies were included. Thirteen papers investigated the association between OSA and self-reported OMD. They all suggested an association between OSA and xerostomia but not between OSA and drooling. The association between CPAP and OMD was addressed in 20 articles. The majority of studies have indicated xerostomia as a CPAP side effect; however, some have observed that xerostomia diminishes with CPAP therapy. In 15 papers, the association between MAD and OMD was investigated. In most publications, both xerostomia and drooling have been described as common side effects of MADs. These side effects are often mild and transient, and they improve as patients continue to use their appliance. Most studies found that these OMDs do not cause or are not a strong predictor of non-compliance.
CONCLUSIONS: Xerostomia is a common side effect of CPAP and MAD, as well as a significant symptom of OSA. It may be regarded as one of the indicators of sleep apnoea. Moreover, MAD therapy can be associated with OMD. However, it seems that OMD may be mitigated by being adherent to the therapy.