Microflora in oral ecosystems in subjects with radiation-induced hyposalivation

Aim:  To analyse the microbial flora in specific oral sites in 13 dentate subjects, 6–8 months after completed radiation therapy (RT group) and in 13 matched controls.
Material and methods:  The microflora on the tongue, buccal mucosa, vestibulum, supragingival plaque and subgingival region was analysed using duplicate sampling and cultivation technique. A clinical examination was also performed.
Results:  Candida albicans was found in one or more sites in 54% of the RT subjects and in 15% of the controls. In three RT subjects, C. albicans was found at all four sites analysed. An unexpected finding was that enterococci were found in all RT subjects and in high number in 38%. None of the controls harboured enterococci. In supragingival plaque, Lactobacillus spp. were detected in 92% of the RT subjects and the number and proportion of Lactobacillus spp. were extremely high compared with the controls. Mutans streptococci were detected in high numbers in 31% of the RT subjects, while they were not detected in 23%.
Conclusion:  The microbial results explain why some RT subjects have an increased susceptibility to oral diseases and stress that site-specific microbial analysis is an important diagnostic tool when planning oral health preventive care for RT subjects.     

Oral microbiota associated with hyposalivation of different origins

We analysed and compared the oral microbial flora in four groups with hyposalivation caused by radiation therapy (RT), primary Sj?gren's syndrome (pSS), medication or unknown factors (Unknown), or neuroleptic treatment (Neuro). A control group with normal salivary secretion was also included. The subjects included were 54 +/- 8 years old and had 25 +/- 4 teeth. We analysed their microflora in rinsing samples using a cultivation technique. A marked increase in Lactobacillus spp. and Candida albicans was characteristic of the RT group. In the pSS group, 85% of subjects had high numbers of mutans streptococci despite good oral hygiene, frequent dental visits and fluoride use. The Unknown group had an oral flora similar to that of the controls. In the Neuro group, with a stimulated secretion rate similar to that of the Unknown group, the numbers of aciduric and acidogenic microorganisms were close to those in the pSS group. The results indicate that changes in the oral microflora associated with hyposalivation are related to the reason for the hyposalivation rather than to the magnitude of the decrease in the salivary secretion rate.     

Self-reported oral and general health related to xerostomia,hyposalivation, and quality of life among caries active younger adults

Abstract

Objective: The aim was to study prevalence of xerostomia, hyposalivation and quality of life among caries active younger adults.

Materials and methods: A questionnaire regarding oral and general health, xerostomia and quality of life was mailed to 134 caries active (CA) and 40 caries inactive (CI) patients, 25–50 years of age (mean age 39.9?±?6.2 years) treated at a Swedish Public Dental Service clinic, regarding oral and general health, xerostomia and quality of life. Caries data and unstimulated whole salivary flow rates were obtained from dental records.

Results: The overall response rate was 69%. Dental records confirmed that CA patients had more decayed teeth over time than CI patients (p?<?.001). The CA group reported worse oral health (p?<?.001) and general health (p?<?.01), more xerostomia (p?<?.001) and lower salivary flow rate (p?<?.01) compared to CI patients. Xerostomia was inversely related to unstimulated whole salivary flow rates as well as to oral and general health (p?<?.01). There were no differences between groups in quality of life.

Conclusion: Younger caries active adult patients reported significantly more xerostomia and hyposalivation compared to caries inactive patients. Xerostomia and hyposalivation were inversely related to perceptions of oral and general health, but not to quality of life.     

Prevalence of hyposalivation in relation to general health, body mass index and remaining teeth in different age groups of adults

Abstract – Objectives: Several studies have been conducted on the prevalence of hyposalivation in older adults but no population‐based studies in younger adults. Therefore, our aims were to determine the prevalence of very low and low unstimulated (UWSFR) and stimulated (SWSFR) whole salivary flow rates in different age groups between 20 and 69 years, and to analyse the relationship between hyposalivation, subjective oral dryness and predictors of reduced flow rate. Methods: A randomized and stratified cross‐sectional study including 1427 dental patients was conducted. UWSFR and SWSFR were measured, numbers of remaining teeth recorded and a questionnaire answered regarding subjective oral dryness, general diseases, use of drugs, body mass index (BMI) and use of tobacco. Results: The prevalence of very low (<0.1 ml/min) and low (0.10–0.19 ml/min) UWSFR was similar for different age groups up to 50 years, ranging between 10.9–17.8% and 17.3–22.7%, respectively. The prevalence of very low UWSFR was significantly higher for women aged 50–69 years than for younger women. For men, prevalence of very low UWSFR was higher at 60–69 years. The prevalence of very low (<0.7 ml/min) and low (0.70 – 0.99 ml/min) SWSFR was between 0–5.5% and 0.8–8.2%, respectively, for the different age groups 20–69 years. Multiple logistic regression revealed that age above 50 years, female gender, having fewer than 20 teeth, and taking xerogenic drugs significantly increased the risk of very low UWSFR. For very low SWSFR, only having fewer than 20 teeth and taking more than two drugs were significant. In the younger individuals (<50 years) only BMI > 25 for very low UWSFR and diagnosed disease for very low SWSFR were found significant. In this younger subset, female gender combined with having fewer than 27 teeth was significant for low UWSFR. Conclusions: Hyposalivation is prevalent in younger adults, among whom it is associated with diagnosed disease and high BMI, while after age 50 years it is associated with medication. It is also associated with gender and with fewer remaining teeth.     

Salivary buffer capacity,pH, and stimulated flow rate of crack cocaine users

Aim: Crack cocaine is the freebase form of cocaine that can be smoked. The use of this drug has been considered a public health problem in many countries. The aim of this study was to assess the stimulated salivary flow rate (SSFR), pH, and the buffer capacity of saliva in crack cocaine users. Methods: Stimulated whole saliva was collected from 54 selected crack cocaine users and 40 non‐users. All samples were analyzed for SSFR, pH, and buffer capacity. SSFR was analyzed by gravimetric method. The buffer capacity and pH were determined using a digital pH meter. Results: The crack cocaine users demonstrated higher buffer capacity than the control group (P > 0.05). Salivary pH was lower in crack cocaine users (P < 0.05). Mean values of the SSFR for the experimental and control groups were 1.1 and 1.3 mL/min, respectively (P > 0.05). Conclusion: Crack cocaine users might exhibit a significant decrease in salivary pH, but not in salivary flow rate or buffer capacity.     

Lactoferrin, amylase and mucin MUC5B and their relation to the oral microflora in hyposalivation of different origins

There are several reasons for hyposalivation, each affecting the salivary composition in different ways. The aim of this study was to analyze and compare lactoferrin, amylase and mucin MUC5B in stimulated whole saliva collected from subjects with hyposalivation of different origins and to relate the results to the presence of some microbial species associated with oral disorders. Albumin was determined as a marker of serum leakage. The characteristic feature for subjects with radiation-induced hyposalivation was a large increase in lactoferrin, probably due to leakage through inflamed mucosal tissues, while it was a high albumin content for the group with primary Sj?gren's syndrome, probably due to disruption of the fragile mucosa. The saliva composition in subjects with hyposalivation of unknown origin or due to medicines was close to that in the healthy controls. All three hyposalivation groups tended to display a decrease in the concentrations of MUC5B and amylase. None of the microbial species analyzed (streptococci, mutans streptococci, Lactobacillus spp., Fusobacterium nucleatum, Prevotella intermedia/Prevotella nigrescens, Candida albicans, Staphylococcus aureus and enterics) correlated with concentration of MUC5B in saliva. The RT group, having the highest concentration of lactoferrin, had the lowest median number of F. nucleatum and was the only group in which median number of P. intermedia/P. nigrescens was zero.     

Salivary flow rates among women diagnosed with benign and malignant tumors

The purpose of this study was to compare salivary flow rates (SWS) among patients diagnosed with benign and varying malignant solid tumors with the comparison group, prior to the initiation of any treatment. An evaluation of the results found that mean baseline SWS flow rates were higher for healthy patients (1.55 ml/min) when compared to patients diagnosed with benign tumors (1.13 ml/min), breast cancer (1.09 ml/min), and reproductive carcinomas (0.94 ml/min). The overall model (F = 7.76; p < .001) and the Dunnett's post hoc analyses were statistically significant at the p < .001 level. Additionally, medications, race, and season of the year had significant effects on mean SWS flow rates. The results suggest that salivary secretion is lower among both benign and malignant tumor subjects prior to the initiation of treatment. Salivary evaluations of subjects prior to treatment may be useful in identifying individuals at risk for oral complications during chemotherapy.     

Prevalence of Candida spp., xerostomia,and hyposalivation in oral lichen planus – A controlled study

Objective

To determine the frequency of Candida spp., xerostomia, and salivary flow rate (SFR) in three different groups: patients with OLP (OLP group), patients with oral mucosal lesions other than OLP (non‐OLP group), and subjects without oral mucosal lesions (control group).

Material and methods

Xerostomia as well as SFR was investigated in the three groups. Samples for isolation of Candida spp. were collected from OLP lesions (38 patients), non‐OLP lesions (28 patients), and healthy subjects (32 subjects).

Results

There was no statistically significant difference regarding the frequency of xerostomia and hyposalivation among the three groups (P > 0.05). A higher prevalence for colonization by Candida spp. was found in the healthy subject as compared to that of patients with OLP (P = 0.03) and non‐OLP (P = 0.02) groups. Low SFR was not a factor for colonization by Candida spp.

Conclusions

Xerostomia and hyposalivation occur with similar frequency in subjects with and without oral lesions; also, the presence of oral lesions does not increase the susceptibility to colonization by Candida spp. It seems that any study implicating Candida spp. in the malignant transformation of oral lesions should be carried out mostly on a biochemical basis, that is, by testing the capability of Candida spp. to produce carcinogenic enzyme.     

Saliva and gastrointestinal functions of taste,mastication, swallowing and digestion

Saliva has multiple essential functions in relation to the digestive process taking place in the upper parts of the gastrointestinal (GI) tract. This paper reviews the role of human saliva and its compositional elements in relation to the GI functions of taste, mastication, bolus formation, enzymatic digestion, and swallowing. The indirect function of saliva in the digestive process that includes maintenance of an intact dentition and mucosa is also reviewed. Finally, pathophysiological considerations of salivary dysfunction in relation to some GI functions are considered.     

Salivary secretion, mucin concentrations and candida carriage in HIV-infected patients

Objectives:  To test whether the submandibular/sublingual (SMSL) salivary secretion, mucin concentration and candida carriage status were altered in human immunodeficiency virus-positive (HIV+) patients.
Subjects and methods:  SMSL saliva collected from 48 HIV-infected and 31 HIV-negative men were analyzed for flow rates, total protein and mucin concentrations. Salivary cultures were performed for Candida assessment.
Results:  The salivary flow rate and protein secretion of the HIV+ patients was 37% and 32% less than that of the controls ( P  <   0.0001, P  =   0.0087). The mucin concentrations (MG1 and MG2) were higher in the HIV+ subjects compared with controls ( P  =   0.0186, P  =   0.0014); however, the mucin secretions were not different. The frequency of Candida -positive cultures was higher in the HIV+ subjects than in the controls (61.4% vs 24.1%, P  =   0.0018). In the HIV-infected group, the unstimulated SMSL flow rates were lower in Candida -positive than in Candida -negative patients ( P  =   0.0158).
Conclusion:  The salivary secretion of the SMSL glands was reduced in HIV infection. Although the mucin concentration increased in HIV+ subjects, mucin secretion was not altered. Highly active antiviral therapy had no effect on salivary function. We found an association between the level of candida carriage and salivary flow rate in HIV-infected patients.     

Salivary oncofoetal fibronectin and oral squamous cell carcinoma

Fibronectin (FN) is a multifunctional adhesive glycoprotein that exists in the extracellular matrix and body fluids. As a result of alternative splicing, extra segments (ED-A and ED-B) may be included in the fibronectin molecule. These isoforms of FN, together with FN that has an extra glycosylation (OFFN), are strongly associated with a number of tumours, including oral squamous cell carcinoma (SCC). In view of the likely exfoliation of these cells into the oral cavity from tumours, OFFN might be present in saliva. As such, the presence of OFFN in saliva may be an indicator of oral SCC. The saliva of 12 patients with oral squamous carcinoma and 8 disease-free individuals was measured for OFFN using an enzyme-linked immunoassay. Salivary OFFN levels were similar for patients both with oral SCC and those without, suggesting that this would not be a useful test for the detection of oral SCC.     

Salivary secretion in health and disease

Saliva is a complex fluid produced by 3 pairs of major salivary glands and by hundreds of minor salivary glands. It comprises a large variety of constituents and physicochemical properties, which are important for the maintenance of oral health. Saliva not only protects the teeth and the oropharyngeal mucosa, it also facilitates articulation of speech, and is imperative for mastication and swallowing. Furthermore, saliva plays an important role in maintaining a balanced microbiota. Thus, the multiple functions provided by saliva are essential for proper protection and functioning of the body as a whole and for the general health. A large number of diseases and medications can affect salivary secretion through different mechanisms, leading to salivary gland dysfunction and associated oral problems, including xerostomia, dental caries and fungal infections. The first part of this review article provides an updated insight into our understanding of salivary gland structure, the neural regulation of salivary gland secretion, the mechanisms underlying the formation of saliva, the various functions of saliva and factors that influence salivary secretion under normal physiological conditions. The second part focuses on how various diseases and medical treatment including commonly prescribed medications and cancer therapies can affect salivary gland structure and function. We also provide a brief insight into how to diagnose salivary gland dysfunction.     

Exploring taste hyposensitivity in Japanese senior high school students

Aim: The main objective of this study was to investigate the prevalence of taste hyposensitivity and the relationships between sex, oral health status, and eating habits with taste hyposensitivity in Japanese senior high school students. Methods: Oral examinations, sweet and salt whole‐mouth taste tests, and a questionnaire about eating habits were conducted on 234 senior high school students. Factors affecting taste hyposensitivity were investigated using a multivariate analysis. Results: Sweet‐taste hyposensitivity was observed in 7.3% of the students, and salt‐taste hyposensitivity in 22.2%. Approximately 3% of the students had both sweet‐ and salt‐taste hyposensitivity, and 22.6% had either sweet‐ or salt‐taste hyposensitivity. In total, 26% had a taste hyposensitivity. There were significant relationships between the intake of instant noodles with sweet‐taste hyposensitivity, and the intake of vegetables or isotonic drinks with salt‐taste hyposensitivity. Conclusions: There was a significant association between eating habits and taste hyposensitivity in Japanese senior high school students. Taste tests would be a helpful adjunct for students to recognize variations in taste sensitivity, and a questionnaire about their eating habits might provide an effective self‐review of their eating habits, and therefore, provide motivation to change.     

Salivary diagnostics powered by nanotechnologies, proteomics and genomics

BACKGROUND: The ability to monitor health status, disease onset and progression, and treatment outcome through noninvasive means is a highly desirable goal in health care promotion and delivery. Oral fluid is a perfect medium to be explored for health and disease surveillance. METHODS: Two prerequisites exist before the goal of salivary diagnostics can be achieved: identification of specific biomarkers associated with a health or disease state and the development of technologies that can discriminate between the biomarkers. A recent initiative of the National Institute of Dental and Craniofacial Research has created a roadmap to achieve these goals through the use of oral fluids as the diagnostic medium to scrutinize the health and/or disease status of patients. This is an ideal opportunity to optimize state-of-the-art saliva-based biosensors for salivary biomarkers that discriminate between diseases. RESULTS: Seven technology groups are developing point-of-care salivary diagnostic technologies. Three groups are working together toward deciphering the salivary proteome. CONCLUSION: These collective efforts and the convergence of salivary diagnostic technologies and the salivary proteome will present unparalleled opportunities to explore the diagnostic potential of saliva for oral and systemic diseases.     

Masticatory performance and taste perception in patients submitted to cancer treatment

The aim of this study was to analyse mastication and the sense of taste in 39 patients submitted to cancer treatment in different areas of the body and to compare these variables with those of 44 control individuals within the same age range. The following aspects were assessed: dental status (DMFT); stimulated and non‐stimulated salivary flow; sense of taste (salty, sweet, bitter and sour); and masticatory performance (MP), through the calculation of X₅₀. Logistic regression models were established to test the association between the independent variables and cancer treatment. Cancer patients had lesser stimulated salivary flow, a smaller number of teeth and occlusal units, worse MP, higher salty, sweet and sour taste scores and a lower bitter taste score (P < 0·05). A significant positive correlation was found between MP and the DMFT index in both groups (P < 0·05), meaning that a lower DMFT index value denoted a smaller X₅₀ value (better masticatory performance). The logistic regression model revealed that patients who had undergone cancer treatment had a greater probability of exhibiting a smaller number of teeth, higher salty and smaller bitter taste scores (P < 0·05). It was concluded that patients who were submitted to cancer treatment presented oral physiology alterations when compared with control subjects at the same age range.     

Associations between labial and whole salivary flow rates,systemic diseases and medications in a sample of older people

Smidt D, Torpet LA, Nauntofte B, Heegaard KM, Pedersen AML. Associations between labial and whole salivary flow rates, systemic diseases and medications in a sample of older people. Community Dent Oral Epidemiol 2010; 38: 422–435. © 2010 John Wiley & Sons A/S Abstract – Objective: To investigate the associations between age, gender, systemic diseases, medications and labial and whole salivary flow rates in older people. Methods: Unstimulated labial (LS) and unstimulated (UWS) and chewing‐stimulated (SWS) whole salivary flow rates were measured in 389 randomly selected community‐dwelling Danish women and 279 men aged 65–97 years. Systemic diseases, medications (coded according to the Anatomical Therapeutic Chemical (ATC) Classification System), tobacco and alcohol consumption were registered. Results: The number of diseases and medications was higher and UWS lower in the older age groups. On average, women were slightly older, had more diseases, higher medication intake and lower UWS, SWS and LS than men. High number of diseases and medications was associated with low UWS, SWS and LS. In the healthy (14%) and nonmedicated (19%) participants, flow rates were not associated with age and gender, apart from SWS being lower in nonmedicated women. Low UWS were associated with psychiatric and respiratory disorders, type 2 diabetes and intake of psycholeptics, psychoanaleptics (especially SRRIs), respiratory agents, oral antidiabetics (particularly sulfonylureas), magnesium‐hydroxide, cardiac agents, quinine, thiazides, calcium channel blockers, statins, urinary antispasmodics, glucosamine, NSAIDs, opioids and ophthalmologicals. SWS were lower in participants with ophthalmological disorders using ophthalmologicals (especially antiglaucoma agents and miotics), but also in those taking antidepressants, cardiac agents (mostly digitalis glycosides) and calcium channel blockers. Cardiovascular diseases and intake of anti‐thrombotics (mainly low dose aspirins), calcium channel blockers and oral antidiabetics were associated with low LS. Conclusions: In older people, low salivary flow rates are associated with specific and high number of diseases and medications, but neither with age and gender per se nor with tobacco and alcohol consumption. Low UWS are associated with more diseases and medications than SWS and LS, which were primarily associated with cardiovascular diseases and medications including preventive agents such as low‐dose aspirins and statins. New insights into medications and their association with salivary gland function were achieved using the ATC classification system.     

Simplified methods of topical fluoride administration: effects in individuals with hyposalivation

The aim was to compare fluoride (F) levels in individuals with normal salivary secretion and hyposalivation in connection with their use of F solutions and toothpaste. Seven individuals with normal salivation and nine with hyposalivation rinsed with 0.2% NaF solution for 1 minute. In addition, individuals with hyposalivation performed the following: (i) 0.2% NaF rinsing for 20 seconds, (ii) rubbing oral mucosa with a swab soaked with 0.2% NaF solution, and (iii) brushing with 5,000 ppm F (1.1% NaF) toothpaste. Subjects characterized by hyposalivation reached approximately five times higher peak values of F concentrations in saliva after 1 minute rinsing with the F solution and higher area under the curve (AUC) values. The simplified methods exhibited the same AUC values as did 1 minute of rinsing. Brushing with 5,000 ppm F toothpaste resulted in higher AUC values than did the simplified methods. The F concentrations reached higher levels in individuals with hyposalivation compared to those with normal salivation. The simplified methods tested showed similar effects as conventional methods.