Brain Functional Changes before, during, and after Clinical Pain.

This study used an emerging brain imaging technique, functional near-infrared spectroscopy (fNIRS), to investigate functional brain activation and connectivity that modulates sometimes traumatic pain experience in a clinical setting. Hemodynamic responses were recorded at bilateral somatosensory (S1) and prefrontal cortices (PFCs) from 12 patients with dentin hypersensitivity in a dental chair before, during, and after clinical pain. Clinical dental pain was triggered with 20 consecutive descending cold stimulations (32° to 0°C) to the affected teeth. We used a partial least squares path modeling framework to link patients' clinical pain experience with recorded hemodynamic responses at sequential stages and baseline resting-state functional connectivity (RSFC). Hemodynamic responses at PFC/S1 were sequentially elicited by expectation, cold detection, and pain perception at a high-level coefficient (coefficients: 0.92, 0.98, and 0.99, P < 0.05). We found that the pain ratings were positively affected only at a moderate level of coefficients by such sequence of functional activation (coefficient: 0.52, P < 0.05) and the baseline PFC-S1 RSFC (coefficient: 0.59, P < 0.05). Furthermore, when the dental pain had finally subsided, the PFC increased its functional connection with the affected S1 orofacial region contralateral to the pain stimulus and, in contrast, decreased with the ipsilateral homuncular S1 regions ( P < 0.05). Our study indicated for the first time that patients' clinical pain experience in the dental chair can be predicted concomitantly by their baseline functional connectivity between S1 and PFC, as well as their sequence of ongoing hemodynamic responses. In addition, this linked cascade of events had immediate after-effects on the patients' brain connectivity, even when clinical pain had already ceased. Our findings offer a better understating of the ongoing impact of affective and sensory experience in the brain before, during, and after clinical dental pain.

School-based intervention for improving the oral health of children in southern Thailand.

OBJECTIVE: A two-year study assessed the benefit of an enhanced oral health promotion program combined with a closely supervised tooth brushing program in schools, using toothpaste containing 1,450 ppm F- and 1.5% arginine, on oral health and dental caries. METHODS: 15 southern Thailand schools and 3,706 pre-school children were recruited: 8 schools with 1,766 children as controls; 7 schools with 1,940 children in the intervention groups. Of the intervention schools five were classified as cooperative school and two as non-cooperative schools, based on the criteria of 80% participation in the prescribed tooth brushing activities. RESULTS: The DMFT and DMFS increments ("enamel and dentine") were 1.19 and 1.91 for the control group and 1.04 and 1.59 for the intervention groups. These represent 12.6% and 16.8% reductions in caries respectively. The DMFT and DMFS increments ("dentine threshold") were 0.26 and 0.44 for the control group and 0.19 and 0.29 for the intervention group, representing 26.9%, and 34.1% reductions in caries incidence respectively. For the more cooperative schools the benefits were greater: up to a 40.9% reduction in caries for DMFS ("dentine threshold"). At the 24 month examination there were significant improvements in dental plaque scores with greater improvements seen in the intervention group, greater still in the cooperative schools. CONCLUSIONS: This study documents the positive effect from use of fluoridated toothpaste (1,450 ppm F- and 1.5% arginine) administered by schoolteachers and undertaken via an enhanced school oral health program. Optimising oral health interventions for young children in Thai schools may have a significant impact on caries incidence resulting in reductions of up to 34% reductions in caries for all schools included in the study and up to 41% for the most cooperative.

Different Brain Responses to Pain and Its Expectation in the Dental Chair.

A dental appointment commonly prompts fear of a painful experience, yet we have never fully understood how our brains react to the expectation of imminent tooth pain once in a dental chair. In our study, 21 patients with hypersensitive teeth were tested using nonpainful and painful stimuli in a clinical setting. Subjects were tested in a dental chair using functional near-infrared spectroscopy to measure cortical activity during a stepwise cold stimulation of a hypersensitive tooth, as well as nonpainful control stimulation on the same tooth. Patients' sensory-discriminative and emotional-cognitive cortical regions were studied through the transition of a neutral to a painful stimulation. In the putative somatosensory cortex contralateral to the stimulus, 2 well-defined hemodynamic peaks were detected in the homuncular orofacial region: the first peak during the nonpainful phase and a second peak after the pain threshold was reached. Moreover, in the upper-left and lower-right prefrontal cortices, there was a significant active hemodynamic response in only the first phase, before the pain. Subsequently, the same prefrontal cortical areas deactivated after a painful experience had been reached. Our study indicates for the first time that pain perception and expectation elicit different hemodynamic cortical responses in a dental clinical setting.

Dentists' perspectives on caries-related treatment decisions.

OBJECTIVE: To assess the impact of patient risk status on Colombian dentists' caries related treatment decisions for early to intermediate caries lesions (ICDAS code 2 to 4). METHODS: A web-based questionnaire assessed dentists' views on the management of early/intermediate lesions. The questionnaire included questions on demographic characteristics, five clinical scenarios with randomised levels of caries risk, and two questions on different clinical and radiographic sets of images with different thresholds of caries. RESULTS: Questionnaires were completed by 439 dentists. For the two scenarios describing occlusal lesions ICDAS code 2, dentists chose to provide a preventive option in 63% and 60% of the cases. For the approximal lesion ICDAS code 2, 81% of the dentists chose to restore. The main findings of the binary logistic regression analysis for the clinical scenarios suggest that for the ICDAS code 2 occlusal lesions, the odds of a high caries risk patient having restorations is higher than for a low caries risk patient. For the questions describing different clinical thresholds of caries, most dentists would restore at ICDAS code 2 (55%) and for the question showing different radiographic thresholds images, 65% of dentists would intervene operatively at the inner half of enamel. No significant differences with respect to risk were found for these questions with the logistic regression. CONCLUSION: The results of this study indicate that Colombian dentists have not yet fully adopted non-invasive treatment for early caries lesions.

Quantitative light-induced fluorescence to measure enamel remineralization in vitro.

UNLABELLED: The aim of this study was to compare the ability of quantitative light-induced fluorescence (QLF) and surface microhardness (SMH) to measure the remineralization of enamel subsurface lesions, using a pH-cycling model including treatment with 0-ppm, 550-ppm or 1,100-ppm sodium fluoride (NaF) dentifrices. METHODS: Subsurface lesions were created in human enamel specimens (n = 36) and exposed to a remineralization pH-cycling model for 14 days. The pH-cycling model was performed in an automated system where specimens were subjected to a demineralizing solution for 20 min and treatment for 1 min and were then remineralized for 7 h 39 min, 3 times daily. The treatments consisted of 3 NaF, silica-containing dentifrices (0 ppm F; 550 ppm F; 1,100 ppm F). The outcome variables were: change from baseline in surface hardness and percentage change from baseline in fluorescence. An ANCOVA explored differences between different treatment groups (at the p < 0.05 level). Associations between QLF and SMH were evaluated using Spearman's correlation coefficient. RESULTS: The percentage SMH changes were 14.9 ± 2.1%, 56.6 ± 9.6% and 103.9 ± 14.6% for the 0-, 550- and 1,100-ppm F dentifrices, respectively. The percentage fluorescence changes were 15.6 ± 7.1%, 59.8 ± 11.9% and 85 ± 13.2%, respectively. The differences between all pairwise comparisons were statistically significant for both methods (p = 0.001). QLF correlated with SMH (r = 0.67). CONCLUSIONS: Both the SMH and QLF methods demonstrated a significant F dose response for toothpaste in this in vitro remineralization model, and both methods were able to distinguish treatments with different F levels.

Measuring initial enamel erosion with quantitative light-induced fluorescence and optical coherence tomography: an in vitro validation study.

BACKGROUND: Measurement of initial enamel erosion is currently limited to in vitro methods. Optical coherence tomography (OCT) and quantitative light-induced fluorescence (QLF) have been used clinically to study advanced erosion. Little is known about their potential on initial enamel erosion. OBJECTIVES: To evaluate the sensitivity of QLF and OCT in detecting initial dental erosion in vitro. METHODS: 12 human incisors were embedded in resin except for a window on the buccal surface. Bonding agent was applied to half of the window, creating an exposed and non-exposed area. Baseline measurements were taken with QLF, OCT and surface microhardness. Samples were immersed in orange juice for 60 min and measurements taken stepwise every 10 min. QLF was used to compare the loss of fluorescence between the two areas. The OCT system, OCS1300SS (Thorlabs Ltd.), was used to record the intensity of backscattered light of both areas. Multiple linear regression and paired t test were used to compare the change of the outcome measures. RESULTS: All 3 instruments demonstrated significant dose responses with the erosive challenge interval (p < 0.05) and a detection threshold of 10 min from baseline. Thereafter, surface microhardness demonstrated significant changes after every 10 min of erosion, QLF at 4 erosive intervals (20, 40, 50 and 60 min) while OCT at only 2 (50 and 60 min). CONCLUSION: It can be concluded that OCT and QLF were able to detect demineralization after 10 min of erosive challenge and could be used to monitor the progression of demineralization of initial enamel erosion in vitro.

A clinical investigation using quantitative light-induced fluorescence (QLF) of the anticaries efficacy of a dentifrice containing 1.5% arginine and 1450 ppm fluoride as sodium monofluorophosphate.

OBJECTIVE: The purpose of this study was to assess the ability of a new dentifrice containing arginine, an insoluble calcium compound, and fluoride to arrest or reverse naturally occurring buccal caries lesions measured using Quantitative Light-induced Fluorescence (QLF). METHODS: Three study groups used dentifrices which contained 1) 1.5% arginine and 1450 ppm fluoride as sodium monofluorophosphate (experimental), 2) 1450 ppm fluoride as sodium monofluorophosphate (positive control), and 3) no fluoride (negative control). All three dentifrices were formulated in the same calcium base. The study participants were from three schools in the city of Chengdu, Sichuan Province, China. A total of 446 of 450 recruited subjects completed the study. Of these, 147 were in the experimental, 148 in the positive control, and 151 in the negative control groups. The initial age of the children was 10-12 years (mean 11.4 +/- 0.54); 47.5% were female. RESULTS: Using QLF, assessments of buccal caries lesions were made at baseline and after three and six months of product use. For AQ, representing lesion volume, the baseline mean value for the three groups was 27.30, and at the three-month examination the mean values were 16.76, 19.25, and 25.89 for the experimental, positive, and negative control dentifrices, respectively. This represents improvements from baseline of 38.6%, 29.5%, and 5.2%. At six months, the deltaQ values for the three groups were 13.46, 18.47, and 24.18, representing improvements from baseline of 50.7%, 32.3%, and 11.4%. For all QLF metrics, deltaF (loss of fluorescence), area, and deltaQ, the differences between the negative control and both the experimental and positive control groups were statistically significant (p < or = 0.01). The differences between the experimental and positive control groups attained statistical significance for deltaQ (p < or = 0.003) at the six-month examination. CONCLUSION: It is concluded that both of the fluoride-containing toothpastes are significantly better at arresting and reversing buccal caries lesions than the non-fluoride toothpaste. Furthermore, it is concluded that the new dentifrice containing arginine, an insoluble calcium compound, and fluoride provides significantly greater anticaries benefit than a dentifrice containing fluoride alone.

A clinical investigation of the efficacy of a dentifrice containing 1.5% arginine and 1450 ppm fluoride, as sodium monofluorophosphate in a calcium base, on primary root caries.

OBJECTIVE: The purpose of this six-month study was to assess the ability of a new dentifrice containing 1.5% arginine, an insoluble calcium compound, and 1450 ppm fluoride, as sodium monofluorophosphate, to arrest and reverse primary root caries lesions in adults. METHODS: Three test groups used dentifrices which contained either: 1) 1.5% arginine and 1450 ppm fluoride as sodium monofluorophosphate in a calcium base (experimental); 2) 1450 ppm fluoride as sodium fluoride in a silica base (positive control); or 3) no fluoride in a calcium base (negative control). The study participants were residents of the city of Chengdu, Sichuan Province, China. In order to take part, subjects had to have at least one non-cavitated primary root caries lesion. A total of 412 subjects completed the study. They were aged from 50 to 70 years (mean age 64 +/- 4.1 years) and 53.6% were female. Efficacy for arresting and reversal of primary root caries was assessed by clinical hardness measures and through the use of the Electrical Caries Monitor. RESULTS: After three months of product use, clinical hardness measures showed that 27.7%, 24.6%, and 13.1% of lesions had improved in the experimental, positive, and negative control groups, respectively, and 0.7%, 4.5%, and 16.8% had become worse, respectively. The differences in the distribution of lesion change between the negative control group and both the experimental (p < 0.001) and positive control (p = 0.001) were statistically significant. The Electrical Caries Monitor was also used as an objective measure of lesion severity. The end values increased from baseline to the three-month examinations, but none of the differences between the groups attained statistical significance. After six months, clinical hardness measures showed that only one lesion (0.7%) was worse than at the baseline examination-in the experimental group compared to 9.0% and 18.2% in the positive and negative control groups, respectively. In addition, 61.7%, 56.0%, and 27.0%, respectively, showed improvement for the three groups. The differences in the distribution of lesion change scores between the negative control group and both the experimental (p < 0.001) and positive control (p < 0.001) were statistically significant, as was the difference between the experimental group and the positive control (p = 0.006). The Electrical Caries Monitor end values for the experimental, positive, and negative control groups at the six-month examination were 7.9, 1.9 mega omega(s), and 387 kilo omegas(s), respectively. The differences between the negative control group and both the experimental (p < 0.001) and positive control (p < 0.001) were statistically significant. The difference between the experimental and positive control groups was also statistically significant (p = 0.03). CONCLUSION: It is concluded that the new toothpaste containing 1.5% arginine and 1450 ppm fluoride, as sodium monofluorophosphate in a calcium base, provided greater anticaries benefits than a conventional toothpaste containing 1450 ppm fluoride. Both fluoride toothpastes demonstrated greater benefits than non-fluoride toothpaste.

The caries continuum: opportunities to detect, treat and monitor the re-mineralization of early caries lesions.

The aim of this review is to discuss dental caries as a dynamic process of de-mineralization and re-mineralization with progression, arrest or reversal of lesions reflecting the balance between them. The need for new clinical trial designs to assess oral care products which reflect and monitor these processes is highlighted and discussed. The research evidence to support the use of two state-of-the-art methods that focus on re-mineralization of natural root caries lesions and natural enamel lesions is described. The use of the Electrical Caries Monitor (ECM) in combination with clinical scoring of lesions to assess the hardness of root dentin and the use of Quantitative Light-induced Fluorescence (QLF) to measure enamel lesions are described together with a number of studies that have employed the methods to assess the efficacy of oral care products. It can be concluded that quantification of the re-mineralization provided by oral care products assessed using both buccal caries and root caries study designs is a valid approach to developing understanding of the mechanism of action of a new technology and to establishing its clinical efficacy in respect of arresting and reversing early caries lesions, and it complements, enhances and may ultimately supplant the information from a conventional two- to three-year clinical trial measuring effects at the cavitation level.

The anti-caries efficacy of a dentifrice containing 1.5% arginine and 1450 ppm fluoride as sodium monofluorophosphate assessed using Quantitative Light-induced Fluorescence (QLF).

OBJECTIVE: To compare the efficacy of a new dentifrice containing 1.5% arginine, an insoluble calcium compound and 1450 ppm fluoride to arrest and reverse naturally occurring buccal caries lesions in children relative to a positive control dentifrice containing 1450 ppm fluoride alone. STUDY DESIGN: Participants from Chengdu, Sichuan Province, China tested three dentifrices: a new dentifrice containing 1.5% arginine, an insoluble calcium compound, and 1450 ppm fluoride, as sodium monofluorophosphate, a positive control dentifrice containing 1450 ppm fluoride, as sodium fluoride, in a silica base, and a matched negative control dentifrice without arginine and fluoride. Quantitative Light-induced Fluorescence (QLF) was used to assess buccal caries lesions at baseline and after 3 and 6 months of product use. RESULTS: 438 participants (initial age 9-13 years (mean 11.1±0.78) and 48.6% female) completed the study. No adverse events attributable to the products were reported during the course of the study. The subject mean ΔQ (mm(2)%), representing lesion volume, was 27.26 at baseline. After 6 months of product use, the ΔQ values for the arginine-containing, positive and negative control dentifrices were 13.46, 17.99 and 23.70 representing improvements from baseline of 50.6%, 34.0% and 13.1%. After 6 months product use, the differences between the pair wise comparisons for all three groups were statistically significant (p<0.01). The arginine-containing dentifrice demonstrated an improvement after only 3 months that was almost identical to that achieved by the conventional 1450 ppm fluoride dentifrice after 6 months. CONCLUSION: The new dentifrice containing 1.5% arginine, an insoluble calcium compound, and 1450 ppm fluoride provides statistically significantly superior efficacy in arresting and reversing buccal caries lesions to a conventional dentifrice containing 1450 ppm fluoride alone.

Comparison of the efficacy of a dentifrice containing 1.5% arginine and 1450 ppm fluoride to a dentifrice containing 1450 ppm fluoride alone in the management of early coronal caries as assessed using Quantitative Light-induced Fluorescence.

OBJECTIVE: To compare the efficacy of a new dentifrice containing 1.5% arginine, an insoluble calcium compound, and 1450 ppm fluoride to a matched, positive control dentifrice containing 1450 ppm fluoride in arresting and reversing early coronal caries lesions in children using Quantitative Light-induced Fluorescence (QLF). STUDY DESIGN: 331 children from Chiang Mai, Thailand, aged 7-14 years, with one or more visible early enamel caries lesions on the upper anterior teeth, completed the study. The new dentifrice contained 1.5% arginine, an insoluble calcium compound, and 1450 ppm fluoride, as sodium monofluorophosphate; the matched positive control contained 1450 ppm fluoride only. Subjects brushed twice daily at home and additionally once on school days under teacher's supervision. Digital images of the upper six anterior teeth were captured at the baseline, 3- and 6-month examinations using a custom apparatus for reproducible acquisition of Quantitative Light-induced Fluorescence data. RESULTS: At the 3-month examination, the ΔQ (representing lesion volume) for the test group decreased from a mean of 28.62 at baseline to 20.53 mm(2)% and for the positive control group to 23.38 mm(2)%. The difference between groups was not statistically significant (p=0.055). At the 6-month examination, the ΔQ decreased for the test group to 15.85 mm(2)% and for the positive control group to 20.35 mm(2)%. The difference between groups was statistically significant (p<0.001). CONCLUSION: A new dentifrice containing 1.5% arginine, an insoluble calcium compound, and 1450 ppm fluoride, as sodium monofluorophosphate, provided statistically significant superior efficacy in arresting and reversing active coronal caries lesions in children than brushing with a matched positive control dentifrice containing fluoride alone.

Comparing the efficacy of a dentifrice containing 1.5% arginine and 1450 ppm fluoride to a dentifrice containing 1450 ppm fluoride alone in the management of primary root caries.

OBJECTIVE: To compare the efficacy of a new dentifrice containing 1.5% arginine and 1450 ppm fluoride to a positive control dentifrice containing 1450 ppm fluoride alone in arresting and reversing primary root caries lesions in adults. STUDY DESIGN: A total of 3779 subjects from Piracicaba, Säo Paulo, Brazil were screened; 284 had at least one leathery primary root caries lesion and were eligible for the study. The new dentifrice contained 1.5% arginine, an insoluble calcium compound, and 1450 ppm fluoride, as sodium monofluorophosphate; the matched positive control dentifrice contained 1450 ppm fluoride. One lesion for each subject was selected for inclusion in the study and was examined at baseline, 3 and 6 months. RESULTS: A total of 253 subjects completed the study with 129 of 144 subjects included in the final statistical analysis for the test dentifrice and 124 of 140 for the positive control. The mean age of subjects was 45.7 (±9.19) years and 56.5% were female. After 6 months product use, 70.5% of root caries lesions improved for subjects using the arginine-containing dentifrice compared to 58.1% for subjects using the positive control. The difference in the number of root caries lesions becoming hard in the two groups was statistically significant (p=0.038). CONCLUSION: A new dentifrice containing 1.5% arginine, an insoluble calcium compound, and 1450 ppm fluoride, as sodium monofluorophosphate, provided statistically significantly superior efficacy in arresting and reversing active root caries lesions in adults compared to a matched positive control dentifrice containing fluoride alone.

A randomized clinical trial of the anti-caries efficacy of 5,000 compared to 1,450 ppm fluoridated toothpaste on root caries lesions in elderly disabled nursing home residents.

Root caries is prevalent in elderly disabled nursing home residents in Denmark. This study aimed to compare the effectiveness of tooth brushing with 5,000 versus 1,450 ppm of fluoridated toothpaste (F-toothpaste) for controlling root caries in nursing home residents. The duration of the study was 8 months. Elderly disabled residents (n = 176) in 6 nursing homes in the Copenhagen area consented to take part in the study. They were randomly assigned to use one of the two toothpastes. Both groups had their teeth brushed twice a day by the nursing staff. A total of 125 residents completed the study. Baseline and follow-up clinical examinations were performed by one calibrated examiner. Texture, contour, location and colour of root caries lesions were used to evaluate lesion activity. No differences (p values >0.16) were noted in the baseline examination with regards to age, mouth dryness, wearing of partial or full dentures in one of the jaws, occurrence of plaque and active (2.61 vs. 2.67; SD, 1.7 vs.1.8) or arrested lesions (0.62 vs. 0.63; SD, 1.7 vs. 1.7) between the 5,000 and the 1,450 ppm fluoride groups, respectively. Mean numbers of active root caries lesions at the follow-up examination were 1.05 (2.76) versus 2.55 (1.91) and mean numbers of arrested caries lesions were 2.13 (1.68) versus 0.61 (1.76) in the 5,000 and the 1,450 ppm fluoride groups, respectively (p < 0.001). To conclude, 5,000 ppm F-toothpaste is significantly more effective for controlling root caries lesion progression and promoting remineralization compared to 1,450 ppm F-toothpaste.

Non-cavitated carious lesions detection methods: a systematic review.

The aim of this study was to critically appraise the performance of detection methods for non-cavitated carious lesions (NCCLs). A detailed search of Medline (via OVID), the Cochrane Collaboration, Scielo and EMBASE identified 2054 publications. After title and abstract review by three investigators (JG, MT, AI), 124 publications were selected for further review. The final publications evaluated the following methods: Visual (V), Caries Lesion Activity Assessment (CLAA), Laser Fluorescence (LF), Radiographic (R), Fibre-optic Transillumination (FOTI), Electrical Conductance (EC) and Quantitative Light-induced Fluorescence (QLF). All included studies used histological assessment as a gold standard for in vitro studies or clinical/visual validation for the in vivo designs. They reported outcomes measures such as sensitivity (SE), specificity (SP), area under the receiver operating characteristic curve (AUROC) and reliability. Data were extracted from the selected studies independently by two reviewers and checked for errors. The quality of the studies was evaluated as described by Bader et al. (2002). Of the 124 articles, 42 were included that described 85 clinical assessments. Overall, the quality of evidence on detection methods was rated 'poor', except for EC that was rated 'fair'. The SE rates were as follows: V (0.17­0.96), LF or DIAGNOdent (DD) (0.16­0.96), R (0.12­0.84), FOTI (0.21­0.96), EC (0.61­0.92) and QLF (0.82). The SP rates were as follows: V (0.46­1.0), LF (0.25­1.00), R (0.55­0.99), FOTI (0.74-0.88), EC (0.73­1.0) and QLF (0.92). There is a large variation in SE and SP values for methods and a lack of consistency in definition of disease and analytical methods. EC and QLF seem to be promising for detection of early lesions. For both cost and practicality considerations, visual methods should remain the standard for clinical assessment in dental practice.

Effect of post-brushing mouthwash solutions on salivary fluoride retention--study 2.

OBJECTIVE: This study evaluated the effects of three post-brushing mouthwashes containing 0 ppm F, 225 ppm F, and 500 ppm F, respectively, on salivary fluoride retention after brushing with 1450 ppm fluoride (as NaF) toothpaste and rinsing with water immediately after brushing. METHODS: In this three-phase, randomized, cross-over study, an ion-specific electrode was used to measure salivary F levels in thirty trial participants before brushing (Time 0), and after brushing, rinsing with water, and then rinsing with one of the three mouthwashes. Time points evaluated after brushing were one, three, five, 10, 20, 30, 45, and 60 minutes. For saliva sample collections, subjects were asked to pool saliva in their mouths for 10 seconds before spitting out into a container for each of the time points. RESULTS: The AUC0-60 means for F in saliva were 554, 252, and 20 for the 500, 225, and 0 ppm F mouthwash groups, respectively. The 500 ppm F mouthwash resulted in a 2660% increase in total fluoride salivary retention over 60 minutes when compared with the 0 ppm F group, and a 120% increase when compared with the 225 ppm F group. A significant difference (p < 0.001) in the AUC0-60 means between the three groups was observed using analysis of variance (ANOVA). Paired t-tests also showed significant differences in the mean fluoride retention over 60 minutes for all three pair-wise group comparisons (p < 0.001). CONCLUSION: Use of a fluoride mouthwash containing 225 ppm F or 500 ppm F produced a significant increase in salivary fluoride retention following brushing with a 1450 ppm F toothpaste and rinsing with water compared to rinsing without fluoride. The use of the 500 ppm F mouthwash may be of particular benefit to those at high caries risk.

Caries clinical trial methods for the assessment of oral care products in the 21st century.

Traditionally, caries clinical trials of oral care products have focused on the prevention of caries in children and adolescents at the "cavitation" level. Because of a general reduction in caries incidence and the use of positive control comparators, studies have grown both in size and duration to improve statistical power. Currently, they tend to be of 2 to 3 years' duration, with up to 2,000 high-risk individuals per group. During the past decade, there has been a shift in emphasis from a restorative approach to the treatment of dental caries to a therapeutic approach focused on the remineralization of early caries lesions. However, caries clinical trials of oral care products have not often reflected this paradigm change. This manuscript reviews alternative caries clinical trial methods for oral care products. It is concluded that methods focused on the detection and monitoring of enamel caries and root caries, by visual approaches such as ICDAS and instrumental methods such as QLF, Diagnodent, and Electrical Caries Monitors, provide viable alternatives to traditional methods. In particular, such approaches more accurately reflect the modes of action of many therapeutic agents and formulations and may reduce the cost and duration of product innovation.