Sucrose Rinse Research Articles

Sucrose rinse modulates the salivary behavior of carbonic anhydrase VI and its buffering capacity: a longitudinal study in 4 to 6.5-year-old children.

Carbonic anhydrase VI (CA VI) is crucial in regulating oral pH and predicting susceptibility to dental caries. The hypothesis posits that caries activity may alter the CA VI function, diminishing its capacity to regulate pH effectively and potentially exacerbating cariogenic challenges. This 1-year cohort study sought to investigate the enzymatic activity of salivary CA VI and buffering capacity following a 20% sucrose rinse in 4 to 6.5-year-old children. This research involved 46 volunteers categorized into three groups based on their caries status after follow-up: caries-free (CFee), arrested caries (CArrested), and caries active (CActive). Children underwent visible biofilm examination and saliva collection for salivary flow rate, buffering capacity, and CA VI analyses before and after a 20% sucrose rinse. A reduction in the buffering capacity was observed after sucrose rinse in all groups. The CA VI activity decreased significantly in CFee and CArrested groups after sucrose rinse, although it did not change in the CActive group. An improvement in the buffering capacity and salivary flow rate was found at follow-up when compared with the baseline. After 1-year follow-up, buffering capacity and salivary flow rate increased in all groups, whilst the CA VI activity reduced only in CFree and CArrested children. Sucrose rinse universally reduces the salivary buffering capacity, while caries activity may disrupt CA VI activity response during a cariogenic challenge. After a year, increased salivary flow enhances buffering capacity but not CA VI activity in caries-active children.

Pre-treatment oral microbiome analysis and salivary Stephan curve kinetics in white spot lesion development in orthodontic patients wearing fixed appliances. A pilot study

BackgroundWhite spot lesions (WSLs) are a formidable challenge during orthodontic treatment, affecting patients regardless of oral hygiene. Multifactorial in nature, amongst potential contributors to their development are the microbiome and salivary pH. The aim of our pilot study is to determine if pre-treatment differences in salivary Stephan curve kinetics and salivary microbiome features correlate with WSL development in orthodontic patients with fixed appliances. We hypothesize that non-oral hygiene determined differences in saliva could be predictive of WSL formation in this patient population through analysis of salivary Stephan curve kinetics, and that these differences would further manifest as changes in the oral microbiome.MethodsIn this prospective cohort study, twenty patients with initial simplified oral hygiene index scores of “good” that were planning to undergo orthodontic treatment with self-ligating fixed appliances for at least 12 months were enrolled. At pre-treatment stage, saliva was collected for microbiome analysis, and at 15-minute intervals after a sucrose rinse over 45 min for Stephan curve kinetics.Results50% of patients developed a mean 5.7 (SEM: 1.2) WSLs. There were no differences in saliva microbiome species richness, Shannon alpha diversity or beta diversity between the groups. Capnocytophaga sputigena exclusively and Prevotella melaninogenica predominantly were found in WSL patients, while Streptococcus australis was negatively correlated with WSL development. Streptococcus mitis and Streptococcus anginosus were primarily present in healthy patients. There was no evidence to support the primary hypothesis.ConclusionsWhile there were no differences in salivary pH or restitution kinetics following a sucrose challenge and no global microbial differences in WSL developers, our data showed change in salivary pH at 5 min associated with an abundance of acid-producing bacteria in saliva. The results suggest salivary pH modulation as a management strategy to inhibit the abundance of caries initiators. Our study may have uncovered the earliest predecessors to WSL/caries development.

Biofilm accumulation and sucrose rinse modulate calcium and fluoride bioavailability in the saliva of children with early childhood caries

This study aimed at investigating the combined effect of biofilm accumulation and 20% sucrose rinse on the modulation of calcium (Ca2+), phosphate (Pi), and fluoride (F−) bioavailability in the saliva of children with early childhood caries (ECC). Fifty-six preschoolers of both genders were evaluated according to caries experience and activity: caries-free (CF, n = 28) and with ECC (n = 28) and then, submitted to biofilm intervention (biofilm accumulation). In each situation, saliva samples were collected before and five minutes after a 20% sucrose rinse to determine the concentrations of Ca2+, Pi, and F−. Calcium concentration was significantly lower in the biofilm accumulation situation compared to the situation of biofilm mechanical control (p ≤ 0.01), except for CF children after sucrose rinse. Biofilm accumulation increased salivary calcium concentration in children with ECC after sucrose rinse (p = 0.04), whereas mechanical biofilm control reduced it in both groups (p = 0.000). Phosphate concentration was influenced by mechanical control of biofilm in CF children (p = 0.03). The fluoride bioavailability was reduced by sucrose rinse and biofilm accumulation in CF and ECC children (p ≤ 0.002). In conclusion, the combined effect of biofilm accumulation and sucrose rinse modifies the bioavailability of calcium and fluoride in the saliva of children with early childhood caries.

Approximal plaque pH lowering after sugar intake in a periodontally infected dentition

Objectives The aim of this study was to evaluate the effect of periodontal inflammation on the approximal plaque pH after a sucrose rinse. Materials and methods Thirty-two periodontitis patients (aged 38–72 years; 9M/23F) were included. All patients were in need of periodontal surgery. Two non-adjacent interdental spaces, one healthy (no bleeding on probing [BoP] and probing pocket depth [PPD] < 4 mm) and one periodontally diseased (BoP and PPD ≥5 mm) were selected. Before and after surgery, the approximal plaque pH was measured before and after 2, 5 and 10 min after a 1-min rinse with sucrose solution. Results In periodontally diseased interdental spaces, a significant pH drop was seen 5 min after rinsing. In healthy spaces and after surgery, a significant pH drop was seen after 2 min. A multilevel regression analysis showed that greater probing pocket depths were significantly associated with pH change measured 5 min after rinsing (p < .05). Further on, the approximal pH drop after a sucrose rinse tended to be delayed in dentitions with ≥10% of PPD ≥5 mm (p = .052). Conclusions The results suggest that an ongoing periodontal inflammation could temporarily neutralize acidic metabolic products after a sugar challenge. This may further suggest that plaque pH measured after a sugar rinse might be used to identify an ongoing periodontal disease.

The role of mechanical control of biofilm in the salivary pH after sucrose exposure in children with early childhood caries

This quasi-experimental study sought to investigate if the mechanical control of biofilm (3-times-a-day) modifies the saliva’s ability to buffer the oral environment after 20% sucrose rinse (SR20%) in children with early childhood caries (ECC). Here, SR20% reduced the saliva’s pH in both groups and the mechanical control of biofilm had a greater effect on this parameter after SR20% in CF children. The mechanical control of biofilm evidenced a higher buffering capacity in CF children before SR20%, which was not observed after SR20%. Otherwise, the absence of mechanical control of biofilm showed that buffering capacity was comparable in the two groups before SR20%, whereas after SR20% the saliva’s buffering capacity of CF children was higher than ECC children. When biofilm was mechanically controlled, carbonic anhydrase VI activity did not change after SR20% whereas the absence of mechanical control of biofilm reduced this enzyme activity after SR20%. In conclusion, the mechanical control of biofilm did not change saliva’s ability to buffer the oral environment after SR20% in children with ECC. On the other hand, CF children appeared to regulate more effectively the saliva’s pH than ECC children while the absence of mechanical control of biofilm mediated their pH-modifying ability after SR20%.

Urease activity in caries free and caries active children

Few studies have proven that urease has caries inhibiting effect. Urease enzymes hydrolyze urea into ammonia and carbon dioxide. This ammonia raises the pH value of plaque and saliva which will reduce caries activity. The aim of this investigation was to measure and compare the urease activity level before and after carbohydrate rinse in caries free and caries active children of 5-12 years. 30 caries free and 30 caries active children aged 5-12 years were selected for the study. A child was not eligible if he/she has systemic illness and received antibiotics within the last three months. DMFT/dmft was recorded to define the caries status, unstimulated saliva was collected in the eppendorf tubes and supra gingival plaque was collected from all available smooth surfaces. Urease activity was measured following biochemical protocol. Mean, standard deviation, median, and range (min.-max.) of urease activity was calculated. TheIndependent sample t test” was done to compare urease activity in both groups. Paired sample t test” was applied to knowthe change in the urease activity pre and post oral sucrose rinse in saliva and plaque Increased saliva and plaque urease activity was found in caries free group compared to caries active group and in both groups urease activity increased after oral carbohydrate rinse for both saliva and plaque samplesThe strategy can be developed for carbohydrate rinse to generate higher urease activity for caries control and urease activity measurement could be considered as parameter for caries risk assessment in children.

Changes in the salivary electrolytic dynamic after sucrose exposure in children with Early Childhood Caries

This study sought to explore if the effect of 20% sucrose rinse (SR) on the salivary electrolytic concentration of calcium (Ca2+), phosphate (Pi) and fluoride (F−) in children with Early Childhood Caries (ECC) is different from healthy children. Here, fifty-eight preschoolers aged 3 to 5 years were divided into 2 groups: caries-free (CF) and with ECC. Changes in saliva flow rate, pH and buffering capacity (BC), as well as in concentrations of Ca2+, Pi, and F−, and the degree of saturation in relation to hydroxyapatite (DSS HAp) and fluorapatite (DSS FAp) were evaluated. The pre-rinse [Ca2+] was higher in the ECC group in the CF group. A significant increase in [Ca2+] was demonstrated after SR in the CF group (p = 0.05). The [Pi] was reduced by 18% after SR in the ECC group (p = 0.007). The [F-] reduced in both groups after SR (p < 0.000). There was a moderate positive correlation between [Ca2+] and the DSS HAp and DSS FAp. Multivariate analysis showed that children with a higher [Ca2+] in pre-rinse saliva are more likely to have ECC. In conclusion, the effect of a 20% sucrose rinse on the electrolytic concentration of Ca2+, Pi and F- was different when children with ECC were compared with CF children.

Analysis of calcium ions in saliva of the before and after sugar rinse

The purpose of this study was to evaluate the salivary concentration of calcium cations and their variation before and after a sucrose and glucose rinse, and to investigate the relationship between the levels of each compound. Saliva samples were obtained from 34 subjects before and up to 60 min after intake of a 10% sucrose and glucose solution at 2-week intervals. Calcium in human saliva were determined via anion - exchange chromatography with an anion - suppressed conductivity detector using 12mM sulfuric acid. The concentrations of calcium before sucrose rinse were 39.7mg/L(9.3%), respectively. The calcium cation contents in the saliva were reconstituted after the sugar rinse and the concentrations of some ions showed that they are highly related to each other.

PH and bacterial profile of dental plaque in children and adults of a low caries population

ObjectiveThis study compares pH and microbiological profile of dental plaque in children and adults of a low caries population. Material and methodsThirty-nine children, 12–14 years of age and 45 adults between 20 and 39 years of age in 5 Karen villages of the Tak province, Northern Thailand were examined for plaque, calculus, caries (DMFT) and pH measurements in resting plaque and after a sucrose rinse. Information on dietary and oral hygiene habits was obtained through interviews using a fixed questionnaire. Microbiological profile of plaque samples was analyzed with DNA–DNA checkerboard technique. ResultsMean DMFT was 0.77 ± 1.56 and 87% of the adults and 67% of the children were caries free (p < 0.05). The mean resting pH was for both age groups in the range of 7.0–7.1 and significantly higher than a Swedish caries free reference group. Karen adult men had significantly lower pH minimum than females and children (p < 0.05). Supragingival plaque samples showed high levels of low acidogenic and anaerobic species, which dominated over strong acid producers such as streptococci. ConclusionThe study indicates that the Karen children and adults has a plaque physiology and microbiology predominating by low acidogenic anaerobes, which in addition to the low sucrose intake explains the low caries prevalence in this population.

Effect of commonly consumed sugar containing and sugar free fruit drinks on the hydrogen ion modulation of human dental plaque

With the increased awareness of healthy diet among the population, the intake of fruit juices as health drinks has been increased. This study has been designed to check the potential cariogenicity of fruit drinks frequently consumed by infants and young children. To compare the acidogenic potential of sugar free fruit juices with fruit juices containing sugar by evaluating the plaque pH changes, following consumption of the above drinks. The study was carried out on 10 children in the age group of 8-15 years. The four fruit juices used were 1) orange juice with added sugar 2) orange juice with no added sugar 3) apple juice with added sugar 4) apple juice with no added sugar. Sucrose rinse of 10% was used as control group. The endogenous pH of the fruit juices and control was assessed using digital pH meter. The plaque pH was assessed at the baseline and after the consumption of the drinks at 5, 10, 20, 30, 40, and 60 minutes time interval using the plaque-harvesting technique. The obtained results were compiled and subjected to statistical analysis using paired t-test. All the fruit juices showed drop in plaque pH. A drop in pH was also observed in the juices despite of no added sugar content. The fruit juices labeled with "no added sugar" or "free from added sugar", contained substantial quantities of sugar and are equally cariogenic as are fruit drinks with added sugar.

Relationship among Salivary Carbonic Anhydrase VI Activity and Flow Rate, Biofilm pH and Caries in Primary Dentition

This study aimed to determine the activity of carbonic anhydrase isoenzyme VI (CAVI) in the saliva of preschool children with caries and to investigate the relationship between caries and salivary CAVI activity, salivary flow rate and biofilm pH before and after a 20% sucrose rinse. Thirty preschool children aged 45.3–80.3 months were divided into two groups: a caries-free group and a caries group. Clinical examinations were conducted by one examiner (ĸ = 0.95) according to WHO criteria (dmfs) and early caries lesions. From each subject, CAVI activity, salivary flow rate and plaque pH were determined before and after a sucrose rinse. The results were submitted to Wilcoxon, Mann-Whitney and Spearman correlation tests (α = 0.05). The results showed that prerinse CAVI activity and its variation were higher in the saliva from caries children than from caries-free children. No difference was found between the two groups in postrinse salivary CAVI activity. After rinsing, biofilm pH differences were lower in both groups (p = 0.0012 and p = 0.0037 for the caries and caries-free groups, respectively). Also, after the sucrose rinse, salivary flow rate significantly increased in caries and caries-free groups (p = 0.0003, p = 0.0037). The variation of salivary CAVI activity was negatively correlated with caries (r = –0.501, p = 0.005). Child’s age showed a positive correlation with caries (r = 0.456, p = 0.011). These results suggest that variation of salivary CAVI activity and child’s age are associated with dental caries in preschool children.

Effect of a third application of toothpastes (1450 and 5000 ppm F), including a ‘massage' method on fluoride retention and pH drop in plaque

Objective.The aim was to investigate fluoride (F) retention in plaque, saliva and pH drop in plaque using high-F toothpaste (5000 ppm F) or standard toothpaste (1450 ppm F) twice a day or 3-times a day. A method using the toothpaste as a ‘lotion' and massaging the buccal surfaces with the fingertip was also evaluated. Materials and methods.The investigation had a randomized, single-blinded, cross-over design and 16 subjects participated in six brushing regimes: (1) 5000 ppm F; twice a day, (2) 5000 ppm; 3-times/day, (3) 5000 ppm; twice a day, plus the ‘massage' method once a day, (4) 1450 ppm F; twice a day, (5) 1450 ppm; 3-times/day and (6) 1450 ppm; twice a day, plus the ‘massage' method once a day. The outcome measure was F retention in plaque, saliva and the plaque-pH change after a sucrose rinse. Results.The highest F concentration was found using high-F toothpaste (No 1–3) and differed significantly from those with 1450 ppm (No 4–6). Brushing with high-F toothpaste 3-times a day (No 2) resulted in a 3.6-times higher F saliva value compared with standard toothpaste twice a day (No 4) (p < 0.001). Increasing the frequency of application, from twice to 3-times a day, increased the F retention in plaque significantly when the two methods for application 3-times a day were pooled (p < 0.05). Brushing with 5000 and 1450 ppm toothpastes twice a day plus the ‘massage' once a day resulted in the same F concentration in saliva and plaque as brushing 3-times a day with the same paste. Conclusion.A third application of toothpaste is increasing the F retention and toothpaste as a ‘lotion' and massaging the buccal surfaces with the fingertip may be a simple and inexpensive way of delivering F a third time during the day.

Caries Susceptibility of Endodontically versus Nonendodontically Treated Teeth

Introduction The aim of the present investigation was to evaluate the caries susceptibility of endodontically versus nonendodontically treated teeth in relation to dental plaque–related factors. Methods Twenty patients with 2 endodontically treated teeth (ETT) each were examined regarding cariogenic microflora of proximal plaque, in situ plaque pH drop after a sucrose rinse (Stephan curve), and de novo plaque formation. Recurrent caries and the quality of the coronal fillings/crowns of these teeth were also evaluated. ETT were compared with contralateral, nonendodontically treated teeth (NETT). Results Irrespective to the type of restoration, Streptococcus mutans count, de novo plaque formation, and recurrent caries were higher on the surface of ETT compared with NETT ( P < .05). Moreover, the initial (resting) pH in plaque was significantly lower ( P < 0.05) in ETT. Conclusions ETT showed an increased susceptibility to caries as a result of either alteration in their biological environment or inadequacy of the marginal fit of the dental restoration. Clinicians should be aware of this risk.

Oral health in young adults with long-term, controlled asthma

Objective. To study oral health in young adults with long-term, controlled asthma. Material and methods. Twenty 18- to 24-year-olds with a mean duration of asthma of 13.5 [standard deviation (SD) 5.4] years and 20 matched healthy controls were included. A clinical examination was performed and the prevalences of caries, erosions, gingival inflammation, cervicular fluid and periodontal pockets and the plaque formation rate were registered. The salivary flow rate and the numbers of mutans Streptococci and Lactobacilli in saliva were determined. Plaque pH was measured after a sucrose rinse for up to 40 min at two approximal sites. The participants were interviewed regarding dietary and oral hygiene habits. Results. The mean (SD) DFS, including manifest and initial caries, was 8.6 (10.6) in the asthma group and 4.0 (5.2) in the control group (P = 0.09). Initial caries lesions were more common in the asthma group than in the control group: 6.0 (8.1) and 1.3 (2.0), respectively (P = 0.02). The asthma group had more gingivitis (P = 0.01) and a lower stimulated salivary secretion rate than the controls (P = 0.01). The asthmatics also had a somewhat, although not statistically significant, lower initial pH value in plaque and a more pronounced pH drop compared with the controls. In the asthma group, 65% reported frequent mouthbreathing, compared with 10% of the controls (P = 0.01). No differences were found in tooth-brushing or dietary habits between the groups. Conclusion. Young adults with long-term, controlled asthma had more initial caries, more gingival inflammation and a lower stimulated salivary secretion rate than individuals without asthma.

Caries Prevalence, Caries-Related Factors and Plaque pH in Adolescents with Long-Term Asthma

The aim of the present case-control study was to investigate dental caries, various caries-related factors as well as gingival condition, in 12- to 16-year-olds with long-term asthma (n = 20) and a matched healthy control group (n = 20). Data on dietary and oral hygiene habits, numbers of mutans streptococci and lactobacilli in saliva were also obtained. The plaque pH drop after a sucrose rinse was measured up to 40 min at 2 approximal tooth sites. A lower salivary flow rate was found in the asthma group compared to the control group (p < 0.05). The mean (± SD) of DFS, including manifest and initial caries, was 4.9 ± 5.5 in the asthma and 1.4 ± 2.3 (p < 0.01) in the control group. Only 1 adolescent in the asthma group was caries free compared to 13 in the control group. Concerning pH in plaque, adolescents with asthma had a lower initial value (p < 0.01) and final pH (p < 0.05) than the control group. The Cariogram data showed that 55% of the subjects in the control group had ‘a high chance of avoiding caries’ compared to 10% in the asthma group (p < 0.01). The asthmatic adolescents had higher numbers of sites with gingival bleeding (p < 0.01). To conclude, adolescents with long-term asthma had a higher total DFS and caries risk (according to Cariogram), decreased salivary rate, more gingival bleeding and lower plaque pH than adolescents without asthma.

Fluoride releasing restorative materials: Effects of pH on mechanical properties and ion release

Objectives Secondary caries and restorative fracture are the two main reasons for restoration failures. Fluoride ion (F) release can help inhibit caries. Plaque pH after a sucrose rinse can decrease to a cariogenic pH of 4–4.5. The objective of this study was to investigate the effects of solution pH and immersion time on the mechanical properties and F release of restorative materials. Methods Three resin-modified glass ionomers (Viremer, Fuji II LC, Ketac Nano), one compomer (Dyract Flow), and one composite (Heliomolar), were tested. Flexural strength and elastic modulus were measured before and after 84 d of immersion in solutions of pH 4, 5.5, and 7. F release was measured as a function of pH and immersion time. Results Immersion and material type had significant effects on mechanical properties. Vitremer had a flexural strength (mean ± sd; n = 6) of 99 ± 25 MPa before immersion; it decreased to 32 ± 9 MPa after 84 d of immersion ( p < 0.05). In comparison, Heliomolar had a smaller strength loss, decreasing from 99 ± 9 MPa to 65 ± 7 MPa ( p < 0.05). Solution pH had little effect on mechanical properties. For example, Fuji II LC had a strength of 63 ± 15 MPa at pH 4, similar to 61 ± 30 MPa at pH 5.5, and 56 ± 22 MPa at pH 7 ( p > 0.1). In contrast, solution pH had a significant effect on F release. F release at 84 d for Fuji was 609 ± 25 μg/cm 2 at pH 4, much higher than 258 ± 36 μg/cm 2 at pH 5.5, and 188 ± 9 μg/cm 2 at pH 7. Significance The restoratives tested were able to greatly increase the F release at acidic, cariogenic pH, when these ions are most needed to inhibit caries. However, mechanical properties of these F-releasing restoratives degraded significantly in immersion. Efforts are needed to develop F-releasing restoratives with high levels of sustained F release, as well as improved durability of mechanical properties for large stress-bearing restorations.

The ‘Strip Method’: A Simple Method for Plaque pH Assessment

Aim: The aim of the study was to evaluate if pH indicator strips could be used for measurements of plaque pH acidogenicity in situ. Method: Interproximal plaque pH was measured before and up to 60 min after a 10% sucrose rinse in 30 healthy volunteers using pH indicator strips and the microtouch method in parallel. Results: It was found that the ‘strip method’ could determine changes in plaque pH to the same extent as the microtouch method (correlation coefficient 0.99). Conclusion: Since the ‘strip method’ is inexpensive and easy to handle, it may be applicable for assessment of plaque acidogenicity in the clinic.

A study of influence of sugars on the modulations of dental plaque pH in children with rampant caries, moderate caries and no caries

The present study is undertaken to find out the pH of resting plaque in children with no caries, moderate caries and rampant caries and to determine the modulations of plaque pH with different sugar solution rinses viz: sucrose, glucose and fructose. The study was carried out on forty five children, in the age group of 3-10 years (25 males and 20 females). The child was given 10 ml of test solution and was asked to rinse and swish it in the mouth for a period of 30 sec. Plaque samples were taken from 20 different spots after 5, 10, 20 and 30 min of the rinse and pH values of all the samples were determined. Results show that there was a statistically significant (P<0.05) difference between the pH values of plaque at different intervals of time with sucrose, fructose and glucose solution rinse in children with moderate caries, rampant caries as compared to the caries free group. Sucrose was found to be highly cariogenic in all the children with a greater potentiating effect in moderate and rampant caries. Glucose also appeared to have a cariogenic role while fructose had the least of it all.

The effect of casein and calcium containing paste on plaque pH following a subsequent carbohydrate challenge

Objectives Previous research has shown that regular use of CPP–ACP increases calcium and inorganic phosphates in plaque and reduces enamel mineral loss. The aim of this study was to investigate if a CPP–ACP-containing paste would neutralize acidic challenges in dental plaque following sucrose rinse. Method Plaque pH was measured on 15 subjects in a cross-over study with and without prior application of the paste and with and without CPP–ACP. On each occasion, subjects rinsed with 10% sucrose and sorbitol solutions for 2 min in randomized order. Results The results showed the median lowest pH without paste was 4.8 (IQR: 4.7–5.0) and with mousse 5.6 (IQR: 5.5–5.6 and p < 0.001). The median lowest pH was 5.0 (IQR: 4.9–5.3) without CPP–ACP and with CPP–ACP was 5.8 (5.6–6.1 and p < 0.001). The time that pH remained below 5.7 and the time to return to resting pH showed similar differences in all subjects ( p < 0.01). Conclusion The results indicate that prior application of a CPP–ACP-containing paste reduced the fall in plaque pH following a sucrose challenge.

A clinical study on the effect of the prebiotic inulin in the control of oral malodour

The aim of this clinical study was to evaluate the potential of an inulin mouth rinse to reduce the proportions of tongue bacteria associated with oral malodour. Thirteen panellists rinsed with either 10% sucrose or a 10% inulin mouth rinse twice daily for 21 days. Breath odour levels were assessed using a Halimeter† and organoleptic assessment, both before and after sucrose, inulin or water rinses. Tongue pH was registered and the tongue flora was cultured on media selective for total and obligate anaerobes, streptococci and inulin fermenters. There were no differences in baseline Halimeter† levels over the 21 day period, but a slight decrease in organoleptic scores was noted. A reduction in odour levels assessed by Halimeter† and organoleptically was observed immediately after rinsing. The effect was greater by the end of the 21 day regime. Microbial counts remained high, and no significant differences were observed, but there was a trend towards increased streptococcal counts by the end of the 21 day period. Tongue pH baseline levels were approximately neutral, but immediately after carbohydrate rinses a typical Stephan curve was observed. There is some indication that the use of twicedaily carbohydrate mouth rinses (sucrose or the prebiotic inulin) can reduce oral malodour by encouraging the growth of acidogenic bacteria and inhibiting the obligate anaerobes associated with malodour. Inulin is a less cariogenic substrate, and inulin mouth rinsing may provide a novel method for the control of oral malodour. Key words: oral malodour, volatile sulphur compounds, prebiotic, inulin, oral bacteria