Oral Chronic Graft-versus-Host Disease and Oral Health after Allogeneic Hematopoietic Cell Transplantation - What the Care Team Needs to Know.

Oral chronic graft-versus-host disease (cGVHD) can present with a multitude of clinical signs and is associated with morbidity and lower quality of life. Oral cGVHC may affect the oral mucosa (reticular white striae, erythema, and/or ulcerations), the salivary glands (hyposalivation and/or xerostomia) and the peri-oral soft tissues (fibrosis and trismus). This review provides a practical and concise approach to the diagnosis and management of oral health needs in pediatric and adult alloHCT recipients within the first 2 years post-transplantation.

Oral Candida in post-radiotherapy patients with xerostomia/hyposalivation: A narrative review.

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. CONCLUSION: 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.

The use of stem cells in treating xerostomia: a systematic review.

INTRODUCTION: 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. CONCLUSION: Although in its initial stages, the use of stem cells seems to be a promising therapy to alleviate xerostomia regardless of its cause.

Prevalence of Xerostomia and Hyposalivation Among Individuals Attending Oral Cancer Screening in Thailand: A Cross-Sectional Study.

Aim: It has been speculated that the prevalence of xerostomia and hyposalivation might be higher among individuals attending oral cancer screening than among members of the general population. Therefore, this study investigated the prevalence of these conditions and their associated factors among individuals taking part in oral cancer screening and residing in the northeastern provinces of Thailand. Materials and Methods: This cross-sectional study recruited convenient individuals aged ≥40 years with at least one oral cancer risk factor. In total, 561 participants were included. Demographic characteristics and relevant oral cancer risk factors were recorded. A questionnaire comprising five items was used to assess xerostomia. Participants were then categorized into two groups based on the absence or presence of xerostomia. Subsequently, the stimulated salivary flow rate was assessed using the spitting technique to identify hyposalivation. Participants were then separated into two groups depending on the absence or presence of hyposalivation. Univariate and multivariate logistic regression analyses were then performed to identify factors associated with xerostomia or hyposalivation. Results: The mean age of participants was 65.62 ± 9.70 years, and approximately 60% of participants were post-menopausal women. The prevalence of xerostomia was 43.85%, and the prevalence of hyposalivation was 61.50%. It was revealed that age ≥65 years (odds ratio [OR] = 1.57, P = 0.02) and burning sensation in the mouth (OR = 5.36, P < 0.001) were strongly associated with xerostomia. Female participants were more likely to exhibit hyposalivation (OR = 2.38, P = 0.001). Oral cancer risk factors were not associated with xerostomia or hyposalivation. Conclusions: In this study, age ≥65 years and burning sensation were identified as risk factors for xerostomia, whereas female sex was a risk factor for hyposalivation. Dentists should be aware of both conditions. Various interventions to alleviate dry mouth symptoms might be useful for individuals with these risk factors.

Hyposalivation in patients with psoriasis: Association with severity, inflammatory, and anti-inflammatory cytokine biomarkers of the disease.

The aim of the study is to expound the effect of psoriasis on salivary glands by evaluating the secretion of saliva and salivary cytokine biomarkers in patients with psoriasis. This study was conducted by recruiting 120 subjects that included 60 patients diagnosed clinically with active psoriasis and 60 healthy controls who were age and gender matched to psoriatic subjects. Unstimulated whole saliva was collected from all the subjects by spitting method, and levels of tumor necrosis factor-alpha (TNF-α), interferon-gamma (IFN-γ), interleukin-2 (IL-2), and IL-10 (IL-10) were determined via enzyme-linked immunosorbent assay (BT Lab, Shanghai, China). Secretion of saliva in psoriasis patients was considerably reduced than in healthy controls. The concentrations of pro-inflammatory cytokines (TNF-α, IFN-γ, and IL-2) were significantly increased, whereas level of anti-inflammatory cytokine (IL-10) was markedly decreased in the saliva of psoriasis patients with hyposalivation compared to healthy subjects. Our results demonstrated significant negative correlation of salivary flow rates with the disease severity. No significant correlations were obtained between salivary levels of tested cytokines and salivary flow rates in our study. Findings of the study reflect inflammation of salivary glands with reduced salivary flow rates in psoriasis patients. The inflammatory responses in salivary gland tissues by virtue of increased pro-inflammatory cytokines concentrations together with lower anti-inflammatory cytokine levels may have a role in affecting the saliva secretion in psoriasis patients. Secretion of unstimulated saliva in psoriasis patients decreases with the severity and duration of the disease.

Long-Term Outcome Following Treatment With Allogeneic Mesenchymal Stem/Stromal Cells for Radiation-Induced Hyposalivation and Xerostomia.

BACKGROUND: Adipose-derived mesenchymal stem/stromal cells (ASCs) are proposed as a new xerostomia treatment. The study evaluated the long-term safety and effectiveness of allogeneic ASCs in radiation-induced xerostomia among patients with previous oropharyngeal cancer. METHODS: This study constitutes 3-year follow-up on the original 10 patients who received allogeneic ASCs injections to the submandibular and parotid glands as part of the MESRIX-II trial. The MESRIX-II trial included the preliminary 4-month follow-up. The primary endpoint was long-term safety. Secondary endpoints were effectiveness evaluated by changes in salivary flow rate and patient-reported outcomes (PROs). Immune response was evaluated by assessing the development of donor-specific antibodies (DSA). FINDINGS: All 10 MESRIX-II patients completed the long-term follow-up (ie, no missing data). During the long-term follow-up, 2 patients encountered a significant adverse event, which was determined to be unrelated to the treatment. No DSAs were detectable at 3 years. The stimulated salivary flow rate increased significantly from an average of 0.66 mL/minute at baseline to 0.86 mL/minute at follow-up, corresponding to an increase of 0.20 [95% CI 0.08 to 0.30] mL/minute, or approximately 30%. Among the PROs, sticky saliva symptoms were reduced, with a -20.0 [95% CI -37.3 to -2.7] units. INTERPRETATION: In conclusion, this study is the first to present long-term follow-up outcomes of allogeneic ASC treatment as a therapeutic option for radiation-induced xerostomia. The study found that ASC treatment appears safe, and there were no indications of adverse immune responses at the 3-year follow-up. Further studies are warranted to evaluate the findings in larger settings.

Cell type-specific transforming growth factor-ß (TGF-ß) signaling in the regulation of salivary gland fibrosis and regeneration.

Salivary gland damage and hypofunction result from various disorders, including autoimmune Sjögren's disease (SjD) and IgG4-related disease (IgG4-RD), as well as a side effect of radiotherapy for treating head and neck cancers. There are no therapeutic strategies to prevent the loss of salivary gland function in these disorders nor facilitate functional salivary gland regeneration. However, ongoing aquaporin-1 gene therapy trials to restore saliva flow show promise. To identify and develop novel therapeutic targets, we must better understand the cell-specific signaling processes involved in salivary gland regeneration. Transforming growth factor-ß (TGF-ß) signaling is essential to tissue fibrosis, a major endpoint in salivary gland degeneration, which develops in the salivary glands of patients with SjD, IgG4-RD, and radiation-induced damage. Though the deposition and remodeling of extracellular matrix proteins are essential to repair salivary gland damage, pathological fibrosis results in tissue hardening and chronic salivary gland dysfunction orchestrated by multiple cell types, including fibroblasts, myofibroblasts, endothelial cells, stromal cells, and lymphocytes, macrophages, and other immune cell populations. This review is focused on the role of TGF-ß signaling in the development of salivary gland fibrosis and the potential for targeting TGF-ß as a novel therapeutic approach to regenerate functional salivary glands. The studies presented highlight the divergent roles of TGF-ß signaling in salivary gland development and dysfunction and illuminate specific cell populations in damaged or diseased salivary glands that mediate the effects of TGF-ß. Overall, these studies strongly support the premise that blocking TGF-ß signaling holds promise for the regeneration of functional salivary glands.

Evaluation of the Effect of Photobiomodulation on Radiation-Induced Xerostomia in Head and Neck Cancer Patients: A Randomized Clinical Trial.

Introduction: Radiotherapy-induced xerostomia is an important side effect of head and neck cancer (HNC) treatment. Photobiomodulation (PBM) is one of the new emerging methods for preventing or reducing this problem. The aim of this study is to evaluate the effect of PBM on radiation-induced xerostomia in HNC patients. Methods: Thirty-seven patients with HNC who were referred for radiotherapy to Mashhad cancer center. In the case group, an infrared diode laser was used in contact mode on 16 points (covering minor and major salivary glands). The device emitted a wavelength of 810 nm and operated at the power of 200 mW and continuous wave mode. Each area was irradiated for 4 seconds in contact mode with gentle pressure, and the laser energy was 0.8 J with an energy density of 2.85 J/cm2 at the surface of the probe (spot size, 0.28 cm2 ). The total dose was 45.6 J/cm2. The power density was 714.2 w/cm2. In the control group, the sham laser device was used. Subjective xerostomia was evaluated through the LENT SOMA scale (LSS). Stimulated and unstimulated saliva was also assessed. Data were analyzed with SPSS ver22 statistical software. Results: The study included 26 men and 11 women with a mean age of 55.6±15.3 years. In the sixth week, the case group produced more stimulated saliva than the control group (P=0.006). They also had less subjective xerostomia than the control group in weeks four to six. Conclusion: In the present study, PBM had a preventive effect on stimulated saliva and subjective xerostomia and can be recommended as an adjunctive treatment. Further studies with a higher sample size and the use of a low-level laser in more sessions are needed for definitive comment.

Oral Complications and Management Strategies for Cancer Patients: Principles of Supportive Oncology in Dentistry.

PURPOSE OF REVIEW: It is recognized that patients undergoing cancer treatment experience different adverse effects depending on the type of therapy they received. The objective of this work is to provide a scientific evidence-based protocol for oral care in cancer patients. Cancer resection surgery, chemotherapy, and radiotherapy can cause important complications that impact patients' quality of life. RECENT FINDINGS: Cancer patients, from the moment of diagnosis to the end of treatment and subsequent follow-up, have diverse care needs, both from a systemic and local point of view. The implementation of oral care protocols before, during, and after cancer therapy is essential because it helps to identify risk factors for the development of predictable oral complications. It is essential to establish that all cancer patients, before starting treatment, undergo a systematic dental check-up to avoid limitations during treatment and also alter their quality of life. Regular professional oral care maintenance and follow-up programs are essential to maintaining a patient's long-term oral health.

Optimization of the Production Process of Clinical-Grade Human Salivary Gland Organoid-Derived Cell Therapy for the Treatment of Radiation-Induced Xerostomia in Head and Neck Cancer.

Head and neck cancer is a common cancer worldwide. Radiotherapy has an essential role in the treatment of head and neck cancers. After irradiation, early effects of reduced saliva flow and hampered water secretion are seen, along with cell loss and a decline in amylase production. Currently, there is no curative treatment for radiation-induced hyposalivation/xerostomia. This study aimed to develop and optimize a validated manufacturing process for salivary gland organoid cells containing stem/progenitor cells using salivary gland patient biopsies as a starting material. The manufacturing process should comply with GMP requirements to ensure clinical applicability. A laboratory-scale process was further developed into a good manufacturing practice (GMP) process. Clinical-grade batches complying with set acceptance and stability criteria were manufactured. The results showed that the manufactured salivary gland-derived cells were able to self-renew, differentiate, and show functionality. This study describes the optimization of an innovative and promising novel cell-based therapy.

Randomized Double-Blind Placebo-Controlled Study of Salivary Substitute with Enzymatic System for Xerostomia in Patients Irradiated in Head and Neck Region.

This study aims to compare whether the use of a salivary substitute including an enzymatic system clinically reduces the intensity of xerostomia, as well as exploring the impact that this has on the quality of life, in patients who had received radiotherapy in the head and neck (HNC) region. Forty patients who had completed radiotherapy treatment within 6 months to 1 year previously were allocated into an Enzymatic Spray group (n = 21) or a Placebo arm (n = 19). It should be noted that two patients in the Placebo arm declined to participate during phase 2 of the study. All patients were randomized and used both products three times a day for 30 days. For analysis, xerostomia grade, unstimulated (UWS) and stimulated (SWS) salivary flow rate, and quality of life through the University of Washington Quality of Life Questionnaire validated in Portuguese (UW-QoL) were assessed in two phases: Phase 1 (before the use of the products) and Phase 2 (after 30 days of using the products). All clinical data were collected from medical records. Analyzing the salivary substitute with the enzymatic system, an improvement in xerostomia complaints was observed 30 days after using the product; however, this difference was not statistically significant (p > 0.05). Regarding quality of life, no significant differences were observed in relation to the UW-QoL and saliva domain between the groups in the two phases of the study (p > 0.05). The salivary substitute with the enzymatic system may be effective in reducing radio-induced xerostomia symptoms; however, further research is necessary to evaluate the efficacy of this salivary substitute on oral health.

Copper chelation reduces early collagen deposition and preserves saliva secretion in irradiated salivary glands.

Radiation therapy is a first-line treatment for head and neck cancer; however, it typically leads to hyposalivation stemming from fibrosis of the salivary gland. Current strategies to restore glandular function are dependent on the presence of residual functional salivary gland tissue, a condition commonly not met in patients with extensive fibrotic coverage of the salivary gland resulting from radiation therapy. Fibrosis is defined by the pathological accumulation of connective tissue (i.e., extracellular matrix) and excessive deposition of crosslinked (fibrillar) collagen that can impact a range of tissues and given that collagen crosslinking is necessary for fibrosis formation, inhibiting this process is a reasonable focus for developing anti-fibrotic therapies. Collagen crosslinking is catalyzed by the lysyl oxidase family of secreted copper-dependent metalloenzymes, and since that copper is an essential cofactor in all lysyl oxidase family members, we tested whether localized delivery of a copper chelator into the submandibular gland of irradiated mice could suppress collagen deposition and preserve the structure and function of this organ. Our results demonstrate that transdermal injection of tetrathiomolybdate into salivary glands significantly reduced the early deposition of fibrillar collagen in irradiated mice and preserved the integrity and function of submandibular gland epithelial tissue. Together, these studies identify copper metabolism as a novel therapeutic target to control radiation induced damage to the salivary gland and the current findings further indicate the therapeutic potential of repurposing clinically approved copper chelators as neoadjuvant treatments for radiation therapy.

The supportive use of photobiomodulation on salivary glands: a narrative review and meta-analysis.

PURPOSE: 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. DISCUSSION: 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). CONCLUSION: 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.

Late Complications in Long-Term Childhood Cancer Survivors: What the Oral Health Professional Needs to Know.

With diagnostic and therapeutic advances, over 80% of children diagnosed with cancer become long-term survivors. As the number of childhood cancer survivors (CCS) continues to increase, dental practitioners become more likely to have CCS among their patients. CCS may develop late complications from damage caused by their cancer treatment to endocrine, cardiovascular, musculoskeletal, and other organ systems. These complications may surface decades after the completion of treatment. Adverse outcomes of childhood cancer treatment frequently involve oral and craniofacial structures including the dentition. Tooth development, salivary gland function, craniofacial growth, and temporomandibular joint function may be disturbed, increasing oral health risks in these individuals. Moreover, CCS are at risk of developing subsequent malignancies, which may manifest in or near the oral cavity. It is important that dental practitioners are aware of the childhood cancer history of their patients and have knowledge of potential late complications. Therefore, this narrative review aims to inform dental practitioners of late oral complications of cancer treatment modalities commonly used in pediatric oncology. Furthermore, selected common non-oral late sequelae of cancer therapy that could have an impact on oral health and on delivering dental care will be discussed.

Mesenchymal stem cell-derived HGF attenuates radiation-induced senescence in salivary glands via compensatory proliferation.

BACKGROUND & AIM: Irradiation of the salivary glands during head and neck cancer treatment induces cellular senescence in response to DNA damage and contributes to radiation-induced hyposalivation by affecting the salivary gland stem/progenitor cell (SGSC) niche. Cellular senescence, such as that induced by radiation, is a state of cell-cycle arrest, accompanied by an altered pro-inflammatory secretome known as the senescence-associated secretory phenotype (SASP) with potential detrimental effects on the surrounding microenvironment. We hypothesized that the pro-regenerative properties of mesenchymal stem cells (MSCs) may attenuate cellular senescence post-irradiation. Therefore, here we evaluated the effects of adipose-derived MSCs (ADSCs) on the radiation-induced response of salivary gland organoids (SGOs). METHODS: Proteomic analyses to identify soluble mediators released by ADSCs co-cultured with SGOS revealed secretion of hepatocyte growth factor (HGF) in ADSCs, suggesting a possible role in the stem cell crosstalk. Next, the effect of recombinant HGF in the culture media of ex vivo grown salivary gland cells was tested in 2D monolayers and 3D organoid models. RESULTS: Treatment with HGF robustly increased salivary gland cell proliferation. Importantly, HGF supplementation post-irradiation enhanced proliferation at lower doses of radiation (0, 3, 7 Gy), but not at higher doses (10, 14 Gy) where most cells stained positive for senescence-associated beta-galactosidase. Furthermore, HGF had no effect on the senescence-associated secretory phenotype (SASP) of irradiated SGOs, suggesting there may be compensatory proliferation by cell-division competent cells instead of a reversal of cellular senescence after irradiation. CONCLUSION: ADSCs may positively influence radiation recovery through HGF secretion and can promote the ex vivo expansion of salivary gland stem/progenitor cells to enhance the effects of co-transplanted SGSC.

Efectos de inducción recíproca entre periodontitis e hiposalivación: revisión de la literatura / Reciprocal induction effects between periodontitis and hyposalivation: a review of the literature

Muchas investigaciones se han ocupado de evaluar la vinculación entre las afecciones bucales y otras funciones o afecciones del organismo. Algunos de esos estudios han sentado precedentes acerca de la influencia mutua que puede existir entre la fun-cionalidad de las glándulas salivales y la enfermedad periodontal, y cómo la presencia de una condición puede modificar la evolución o inducir la aparición de la otra. El objetivo del presente trabajo es hacer una revisión bibliográfica de las publicaciones cientí-ficas que evalúan los efectos de inducción recíproca que existe entre la enfermedad periodontal y la hi-posalivación. Trabajos de nuestro grupo y de otros autores demuestran que la hiposalivación reduce la capacidad del organismo para defenderse contra las bacterias patógenas, mantener un ambiente sa-ludable y facilitar la cicatrización en la cavidad bu-cal, promoviendo los procesos de inflamación y daño tisular gingivoperiodontal. A su vez, varios estudios reportan que la enfermedad periodontal induce cam-bios en las glándulas salivales y altera el volumen de secreción salival. Por su parte, el sistema endo-cannabinoide (SEC) muestra estar involucrado tanto en el proceso de secreción salival como en la infla-mación y la reabsorción ósea presentes en la enfer-medad periodontal, en tanto que la activación de los mecanismos del SEC emerge como una de las vías a través de las cuales se desarrollaría el fenómeno de inducción recíproca (AU)

Many investigations have focused on evaluating the link between oral conditions and other functions or conditions of the body. Some of these studies have set precedents about the mutual influence that may exist between the functionality of the salivary glands and periodontal disease, and how the presence of one condition can modify the evolution or induce the appearance of the other. The objective of this work is to carry out a bibliographic review of scientific publications that evaluate the reciprocal induction effects that exist between periodontal disease and hyposalivation. Studies by our group and other authors show that hyposalivation reduces the capacity of the organism to defend itself against pathogenic bacteria, maintain a healthy environment and facilitate healing in the oral cavity, promoting inflammation and gingivoperiodontal tissue damage. In turn, several studies report that periodontal disease induces changes in the salivary glands and alters the volume of salivary secretion. In turn, the endocannabinoid system (ECS) is shown to be involved in the salivary secretion process as well as in the inflammation and bone resorption present in periodontal disease, while the activation of ECS mechanisms emerges as one of the pathways through which the reciprocal induction phenomenon would develop (AU)

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.

Non-pharmacologic interventions for management of radiation-induced dry mouth: A systematic review.

OBJECTIVES: 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. METHODS: 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. RESULTS: 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. CONCLUSIONS: 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.

The effect of conditioning regimen and prescribed medications on hyposalivation in haematopoietic cell transplantation (HCT) patients: an 18-month prospective longitudinal study.

OBJECTIVES: Haematopoietic cell transplantation (HCT) preceded by a conditioning regimen is an established treatment option for (non)malignant haematologic disorders. We aim to describe the development of hyposalivation over time in HCT recipients, and determine risk indicators. MATERIALS AND METHODS: A multi-centre prospective longitudinal observational study was conducted. Unstimulated (UWS) and stimulated (SWS) whole saliva was collected before HCT, early post-HCT, and after 3, 6, 12, and 18 months. The effect of type of transplantation (allogeneic vs autologous) and intensity (full vs reduced) of the conditioning regimen on hyposalivation (UWS < 0.2 mL/min; SWS < 0.7 mL/min) was explored. RESULTS: A total of 125 HCT recipients were included. More than half of the patients had hyposalivation early post-HCT; a quarter still had hyposalivation after 12 months. The conditioning intensity was a risk indicator in the development of hyposalivation of both UWS (OR: 3.9, 95% CI: 1.6-10.6) and SWS (OR: 8.2, 95% CI: 2.9-24.6). After 3 and 12 months, this effect was not statistically significant anymore. CONCLUSIONS: Hyposalivation affects the majority of patients early post-HCT. The conditioning intensity and the type of transplantation were significant risk indicators in the development of hyposalivation. The number of prescribed medications, total body irradiation as part of the conditioning regimen and oral mucosal graft-versus-host disease did not influence hyposalivation significantly. CLINICAL RELEVANCE: Because of the high prevalence of hyposalivation, HCT recipients will have an increased risk of oral complications. It might be reasonable to plan additional check-ups in the dental practice and consider additional preventive strategies.