Interplay Between Minerals in Bottled Water and Fluoride Toothpaste and Caries Lesion Remineralization.

OBJECTIVES: he aim of this in vitro study was to evaluate the effects of some bottled waters on fluoride toothpaste efficacy in enhancing caries lesion remineralization. METHODS: Early caries lesions were created in bovine enamel specimens and stratified into treatment groups based on Vickers surface microhardness (VHN). The present study followed a two (fluoride and fluoride-free toothpaste) by five (four bottled waters and tap water) factorial design. The treatment groups were bottled water with the following attributes: (a) 309.9 ppm Ca/1.20 ppm F; (b) 118.4 ppm Ca/0.16 ppm F; (c) 1.00 ppm Ca/1.01 ppm F; and (d) 0.1 ppm Ca/0.04 ppm F and tap water (48.7 ppm Ca/0.7 ppm F). The five water groups were paired either with 1100 ppm fluoride or fluoride-free toothpaste, yielding 10 groups. Specimens were pH-cycled for 10 days with the daily regimen comprised of twice daily toothpaste slurry, with four exposures to water in between. VHN was measured again and the difference was calculated (ΔVHN). Data were analyzed using two-way ANOVA at a 5% significance level. RESULTS: The two-way interaction between water and toothpaste was significant (p<0.001). All groups except fluoride-free toothpaste/bottled water with 0.1 ppm Ca/0.04 ppm F (p=0.411) had significant increases in VHN after pH cycling (p≤0.023). Fluoridated toothpaste resulted in a higher rate of remineralization compared to fluoride-free toothpaste (all p<0.001). Bottled water with 1.20 ppm F/309.9 ppm Ca exhibited the greatest extent of remineralization within fluoride toothpaste groups (p<0.001) and higher remineralization than lower fluoride water in fluoride-free toothpaste groups (p≤0.006). Within the fluoridated toothpaste group, tap water exhibited significantly less remineralization than all bottled waters (all p<0.001). CONCLUSION: Within the limitation of this study, bottled water with higher fluoride and calcium concentrations might improve fluoridated toothpaste efficacy by enhancing remineralization of early enamel caries-like lesions.

Predicting Dental Caries in Young Children in Primary Health Care Settings.

Young children need increased access to dental prevention and care. Targeting high caries risk children first helps meet this need. The objective of this study was to develop a parent-completed, easy-to-score, short, accurate caries risk tool for screening in primary health care settings to identify children at increased risk for cavities. A longitudinal, prospective, multisite, cohort study enrolled (primarily through primary health care settings) and followed 985 (out of 1,326) 1-y-old children and their primary caregivers (PCGs) until age 4. The PCG completed a 52-item self-administered questionnaire, and children were examined using the International Caries Detection and Assessment Criteria (ICDAS) at 12 ± 3 mo (baseline), 30 ± 3 mo (80% retention), and 48 ± 3 mo of age (74% retention). Cavitated caries lesion (dmfs = decayed, missing, and filled surfaces; d = ICDAS ≥3) experience at 4 y of age was assessed and tested for associations with questionnaire items using generalized estimating equation models applied to logistic regression. Multivariable analysis used backward model selection, with a limit of 10 items. At age 4, 24% of children had cavitated-level caries experience; 49% were female; 14% were Hispanic, 41% were White, 33% were Black, 2% were other, and 10% were multiracial; 58% enrolled in Medicaid; and 95% lived in urban communities. The age 4 multivariable prediction model, using age 1 responses (area under the receiver operating characteristic curve = 0.73), included the following significant (P < 0.001) variables (odds ratios): child participating in public assistance programs such as Medicaid (1.74), being non-White (1.80-1.96), born premature (1.48), not born by caesarean section (1.28), snacking on sugary snacks (3 or more/d, 2.22; 1-2/d or weekly, 1.55), PCG cleaning the pacifier with juice/soda/honey or sweet drink (2.17), PCG daily sharing/tasting food with child using same spoon/fork/glass (1.32), PCG brushing their teeth less than daily (2.72), PCG's gums bleeding daily when brushing or PCG having no teeth (1.83-2.00), and PCG having cavities/fillings/extractions in past 2 y (1.55). A 10-item caries risk tool at age 1 shows good agreement with cavitated-level caries experience by age 4.

A 12-Month Randomized Clinical Trial of 38% SDF vs. Restorative Treatment.

PURPOSE: The aim of this 2-arm, parallel-group, 12-mo randomized clinical trial was to compare the effectiveness of semiannual application of 38% silver diamine fluoride (SDF) versus restorative treatment (RT) to manage cavitated caries lesions in primary teeth in a diverse population of children in Michigan. METHODS: Children aged 2 to 10 y with at least 1 soft cavitated lesion (International Caries Detection and Assessment System 5 or 6) with no pain or signs/symptoms of irreversible pulpitis were recruited and randomly assigned to 2 intervention groups. One random lesion per child received 38% SDF (twice, at a 6-mo interval) or RT. All interventions and assessments were done by calibrated dentists. Primary outcome measures were clinical failure rates: minor (e.g., reversible pulpitis, active/soft lesion or progression, restoration loss or need for replacement/repair, secondary caries) and major (e.g., irreversible pulpitis, abscess, extraction). Parent, child, and provider acceptability was also assessed. RESULTS: Ninety-eight children were enrolled and randomized, with a mean (SD) age of 4.8 y (1.8); 46% were female and their mean dmft + DMFT was 6.3 (3.9). Sixty-nine children were assessed at 12 mo (sample was within the planned 30% attrition rate). There were significantly more teeth with minor failures (SDF = 65%, RT = 23%, P ≤ 0.001) and major failures (SDF = 13%, RT = 3%, P ≤ 0.001) in the SDF group than the RT group; 74% of SDF-treated lesions were hard at 12 mo vs. 57% at 6 mo. Providers stated that SDF was easier, faster, and more preferable than RT (P ≤ 0.001). No significant differences were found in parental satisfaction and acceptability. At 12 mo, children in the RT arm felt significantly (P < 0.05) happier with their tooth appearance and stated that their visit to the dentist hurt less. CONCLUSION: At 12 mo, SDF-treated lesions had significantly more minor and major failures than RT, suggesting that SDF-treated teeth need to be closely monitored in a population at high caries risk (ClinicalTrials.gov NCT02601833). KNOWLEDGE OF TRANSFER STATEMENT: The results of this study can be used by clinicians when deciding whether to restore or apply silver diamine fluoride to cavitated lesions in primary teeth. Information on treatment outcomes and parent, child, and provider acceptability can help guide appropriate treatment decisions and need for monitoring.

Three-Dimensional Surface Texture Characterization of In Situ Simulated Erosive Tooth Wear.

This in situ erosive tooth wear (ETW) study tested enamel 3-dimensional (3D) surface texture outcomes for the detection and differentiation of ETW lesions simulated in clinically relevant conditions. Twenty participants enrolled in this 3-arm crossover intraoral ETW simulation and wore their own partial denture for 14 d holding 2 human enamel specimens (per arm). In each arm, participants were assigned to 1 of 3 different dental erosion protocols: severe (lemon juice/pH 2.5), moderate (grapefruit juice/pH 3.5), and no erosion (bottled drinking water, control). Enamel specimens were evaluated by white-light scanning confocal profilometry for 3D surface texture and surface loss (ETW model validation). Individual point clouds were analyzed using standard dental microwear texture characterization protocols for surface roughness and anisotropy. Fractal complexity (Asfc), texture aspect ratio (Str), and arithmetical mean height (Sa) values were generated at baseline, 7 d, and 14 d. Data were analyzed by analysis of variance models suitable for the crossover design with repeated measurements, and correlation coefficients were used to examine the relationship between outcomes. Asfc and Sa differentiated ETW severity (no erosion < moderate < severe, P < 0.001) at days 7 and 14. Asfc and Sa were lower at baseline compared to days 7 and 14 (P < 0.001) for moderate and severe challenges. Asfc increased from day 7 to 14 (P = 0.042) for the severe challenge. For Str, ETW severity did not have a significant effect overall (P = 0.15). Asfc and Sa were highly positively correlated (r = 0.89, P < 0.001), while Asfc and Sa were not correlated overall with Str (r < 0.1, P ≥ 0.25). Enamel surface loss increased with ETW severity (no erosion < moderate < severe, P < 0.001) at days 7 and 14, validating the ETW simulation model. Complexity (Asfc) and roughness (Sa) outcomes were able to detect and differentiate ETW levels, with Asfc being able to monitor the progression of severe lesions. No clear characterization of ETW lesions could be provided by the anisotropy (Str) parameter.

Impact of COVID-19 on Life Experiences of Essential Workers Attending a Dental Testing Facility.

OBJECTIVES: 1) To compare the impact of COVID-19 on the life experiences of essential workers attending a COVID-19 antibody testing clinic at a dental school. 2) To compare responses of dental, non-dental health care, and non-health care essential workers. 3) To assess acceptability/satisfaction of testing done in a dental setting. METHOD: A total of 984 participants completed a self-administered online questionnaire. RESULTS: Over 90% were healthy (i.e., not in a high-risk health-related group for COVID-19), did not have COVID-19 symptoms within 30 d, and always/frequently engaged in preventive measures. Fifty-eight percent thought that they had a 0% to 25% chance of having immunity/antibodies to COVID-19. Non-dental health care workers thought that their chance was significantly higher (P < 0.05) than others. Over 70% were sometimes, frequently, or always worried about their friends and loved ones getting COVID-19 and of resulting financial problems. Dental workers were significantly less afraid than non-dental health care and non-health care providers. For all groups, more than half of the respondents stated that the pandemic had a negative (somewhat worse or worse) impact on daily life (59%), interactions with others (65%), stress levels (66%), and enjoyment of life (56%). There were significant differences among all 3 groups regarding the percentage of individuals with a negative impact on job security (dental, 47%; non-dental health care, 34%; non-health care, 31%). However, more than half of the respondents stated that the pandemic had a positive impact (same, somewhat better, or much better) on caring about one another, self-care, and exercise. Knowing the results of an antibody test would decrease the level of stress and anxiety in 67% of respondents. Over 80% found a COVID-19 test received in a dental setting acceptable, were "definitely" satisfied, and would "definitely" recommend it to a friend, family, or coworker. CONCLUSIONS: These findings support that dental workers are as vulnerable as other essential workers to threats and psychological impacts of COVID-19. They also support the acceptability and satisfaction of testing for a pandemic done in a dental setting. KNOWLEDGE TRANSFER STATEMENT: The results of this study highlight the impact that pandemics such as COVID-19 can have on life experiences of essential workers, including dentists. It also highlights a role that dentistry can play within the broader health care system, during and beyond the current pandemic, to help with surveillance efforts of community health. Testing may also help alleviate stress and anxiety associated with these pandemics.

An In Vitro Investigation of Anticaries Efficacy of Fluoride Varnishes.

Most currently marketed fluoride varnishes (FVs) have not been evaluated for their effectiveness in preventing dental caries. The objective of this study was to investigate the anticaries efficacy, measured as fluoride release into artificial saliva (AS); change in surface microhardness of early enamel caries lesions; and enamel fluoride uptake (EFU) of 14 commercially available FVs and two control groups. Bovine enamel specimens (5×5 mm) were prepared and assigned to 18 groups (n=12). Early caries lesions were created in the specimens and characterized using Vickers microhardness (VHNlesion). FV was applied to each group of specimens. Immediately afterward, specimens were incubated in 4 mL of AS for 18 hours, which were collected and renewed every hour for the first six hours. AS samples were analyzed for fluoride using an ion-specific electrode. Specimens were then brushed for 20 seconds with toothpaste slurry and subjected to pH cycling consisting of a four-hour/day acid challenge and one-minute treatments with 1100 ppm F dentifrice for five days. Microhardness was measured following pH cycling (VHNpost). EFU was determined using microbiopsy. Acid resistance (eight-hour demin challenge) was performed after pH cycling, and microhardness was measured (VHNart) and compared with baseline values to test the FV impact after pH cycling. One-way analysis of variance was used for data analysis (α=0.05). FVs differed in their release characteristics (mean ± SD ranged from 14.97 ± 2.38 µg/mL to 0.50 ± 0.15 µg/mL), rehardening capability (mean ± SD ranged from 24.3 ± 15.1 to 11.7 ± 12.7), and ability to deliver fluoride to demineralized lesions (mean ± SD ranged from 3303 ± 789 µg/cm3 to 707 ± 238 µg/cm3). Statistically significant but weak linear associations were found between ΔVHN(post - lesion), EFU, and fluoride release (correlations 0.21-0.36). The results of this study demonstrated that differences in FV composition can affect their efficacy in in vitro conditions.

The Influence of Distance on Radiant Exposure and Degree of Conversion Using Different Light-Emitting-Diode Curing Units.

OBJECTIVES: To investigate the influence of curing distance on the degree of conversion (DC) of a resin-based composite (RBC) when similar radiant exposure was achieved using six different light-curing units (LCUs) and to explore the correlation among irradiance, radiant exposure, and DC. METHODS AND MATERIALS: A managing accurate resin curing-resin calibrator system was used to collect irradiance data for both top and bottom specimen surfaces with a curing distance of 2 mm and 8 mm while targeting a consistent top surface radiant exposure. Square nanohybrid-dual-photoinitiator RBC specimens (5 × 5 × 2 mm) were cured at each distance (n=6/LCU/distance). Irradiance and DC (micro-Raman spectroscopy) were determined for the top and bottom surfaces. The effect of distance and LCU on irradiance, radiant exposure, and DC as well as their linear associations were analyzed using analysis of variance and Pearson correlation coefficients, respectively (α=0.05). RESULTS: While maintaining a similar radiant exposure, each LCU exhibited distinctive patterns in decreased irradiance and increased curing time. No significant differences in DC values (63.21%-70.28%) were observed between the 2- and 8-mm distances, except for a multiple-emission peak LCU. Significant differences in DC were detected among the LCUs. As expected, irradiance and radiant exposure were significantly lower on the bottom surfaces. However, a strong correlation between irradiance and radiant exposure did not necessarily result in a strong correlation with DC. CONCLUSIONS: The RBC exhibited DC values >63% when the top surface radiant exposure was maintained, although the same values were not reached for all lights. A moderate-strong correlation existed among irradiance, radiant exposure, and DC.

Predicting Caries in Medical Settings: Risk Factors in Diverse Infant Groups.

Expanded partnership with the medical community is a promising strategy for reducing disparities in dental caries among young children. However, no validated caries risk instrument exists for use in primary health care settings. To help resolve this gap, a 52-item caries risk questionnaire was developed and targeted to primary caregivers (PCGs) to test in a 3-y prospective study. To begin to understand the validity of the questionnaire items, the purpose of this study was to compare responses to the questionnaire based on key demographic characteristics known to be associated with disparities in caries experience (e.g., race/ethnicity and insurance status). A total of 1,323 one-year-old children were recruited primarily through 3 medical research networks. Baseline questionnaire responses were analyzed via logistic regression. The sample was 49% female. Its racial/ethnic makeup was as follows: 13% Hispanic, 37% White, 37% Black, and 13% other or multiracial. Sixty-one percent were enrolled in Medicaid, and 95% resided in urban communities. Mothers represented 94% of PCGs. There were significant differences ( P < 0.05) in baseline responses based on Medicaid status and race/ethnicity. As compared with those not enrolled in Medicaid, children in the Medicaid group were significantly more likely (after adjusting for race/ethnicity) to 1) go to sleep while nursing or drinking something other than water, 2) eat sugary snacks between meals, 3) consume sugary drinks between meals, 4) receive topical fluoride from a health professional, 5) visit the dentist, and 6) not have an employed adult in the household. PCGs of children enrolled in Medicaid were significantly more likely to be the mother, have bleeding gums, eat sugary snacks between meals, consume sugary drinks between meals, eat or drink something other than water before going to bed, and not get regular dental checkups. In conclusion, there are significant differences in caries risk questionnaire responses based on Medicaid status and race/ethnicity that provide construct and criterion validity to the developed caries risk tool (ClinicalTrials.gov NCT01707797).

In vitro visual and visible light transillumination methods for detection of natural non-cavitated approximal caries.

OBJECTIVES: The objective was to evaluate a visible-light-transillumination (using Digital Imaging Fiber-Optic Transillumination machine: DIFOTI) method using occlusal view (DIFOTI-occl), axial view (buccal and lingual: DIFOTI-axial), and combination of all views (DIFOTI-all) for detecting non-cavitated approximal caries and to compare its performance to visual examination (International Caries Detection and Assessment System: ICDAS). MATERIALS AND METHODS: Thirty extracted human premolars were selected (sound to lesions into the outer one-third of the dentine) based on micro-computed tomography (µ-CT). Teeth were mounted in a custom-made device to simulate approximal contact. DIFOTI (Electro-Optical Sciences Inc., Irvington, NY, USA) images were obtained from the occlusal, buccal, and lingual views. DIFOTI image and ICDAS examinations were performed and repeated by three trained/calibrated examiners. Sensitivity, specificity, area under receiver operating characteristics curve (Az), inter- and intra-class correlation coefficients (ICCs), and correlation were determined. RESULTS: Sensitivity/specificity was for DIFOTI-occl: 0.42/0.75, DIFOTI-axial: 0.86/0.93, DIFOTI-all: 0.91/0.69, and for ICDAS: 0.89/0.83. Az for DIFOTI-occl was significantly lower than that of DIFOTI-axial (p < 0.001), DIFOTI-all (p = 0.002), and ICDAS (p = 0.005). Spearman correlation coefficients with µ-CT for DIFOTI-occl (r = 0.39) showed weak association, while DIFOTI-axial (r = 0.80), DIFOTI-all (r = 0.91), and ICDAS (r = 0.90) showed moderate association. ICCs for intra-examiner repeatability/inter-examiner agreement were for DIFOTI-occl (0.64/0.58), DIFOTI-axial (0.92/0.89), DIFOTI-all (0.85/0.83), and ICDAS (0.79/0.72). CONCLUSIONS: The results of the current in vitro study suggest that, for detection of non-cavitated approximal caries lesions, DIFOTI performs better using axial than occlusal view. CLINICAL RELEVANCE: Approximal non-cavitated caries detection is challenging. DIFOTI can observe images from occlusal-, buccal-, and lingual views. DIFOTI and visual (ICDAS) examinations of buccal- and lingual- and all-views are more suitable than those of occlusal view for a detection of non-cavitated approximal caries.

Enhancing predicted fluoride varnish efficacy and post-treatment compliance by means of calcium-containing gummy bears.

OBJECTIVES: This study determined whether consumption of calcium-containing gummies prior to fluoride varnish application enhances plaque fluoride retention and compliance with post-varnish application instructions. METHODS: The present study followed a multi-center, parallel, randomized, and laboratory analyst-blind design. Following IRB approval, parent consent and child assent, 44 subjects (7-12 years), were randomized to either gummy or no-gummy study groups. A baseline plaque sample was obtained after a wash-out period. Fluoride varnish (5% NaF) was applied; subjects in the gummy group received two calcium-containing gummies prior to varnish application. Subjects were given two questionnaires to complete (subject and parent) to investigate adherence to post-treatment instructions. Three days later, a second plaque sample was obtained. Plaque was analyzed for plaque fluid and solid fluoride concentrations. Fluoride data were analyzed using Wilcoxon Rank Sum tests, questionnaire data using Pearson chi-square tests. RESULTS: Plaque fluid fluoride did not change pre- to post-treatment in the gummy group (mean ±â€¯sd: 8.8 ±â€¯5.7 µmol/l vs. 10.0 ±â€¯6.3 µmol/l; p = 0.265) or in the no-gummy group (8.1 ±â€¯4.4 µmol/l vs. 16.1 ±â€¯20.0 µmol/l; p = 0.058). Groups were not different for plaque fluid fluoride pre-treatment (p = 1.000), post-treatment (p = 0.904), or change (p = 0.904). Plaque solid fluoride did not change pre- to post-treatment in the gummy group (0.89 ±â€¯1.10 µmol/g vs. 1.37 ±â€¯1.77 µmol/g; p = 0.073) or in the no-gummy group (0.68 ±â€¯0.77 µmol/g vs. 2.01 ±â€¯5.00 µmol/g; p = 0.190). Groups were not different for plaque solid fluoride pre-treatment (p = 1.000), post-treatment (p = 0.466), or change (p = 0.874). No significant differences were found between groups for questionnaire responses. CONCLUSION: This study failed to demonstrate an effect of calcium-containing gummies in enhancing plaque fluoride retention. CLINICAL SIGNIFICANCE: The consumption of calcium-containing gummies prior to fluoride varnish application does not promote greater intra-oral fluoride retention or better adherence to post-treatment instructions.

Association of added sugar intake and caries-related experiences among individuals of Mexican origin.

OBJECTIVE: Determine the association between key dental outcomes and added sugar intake using a survey instrument to assess added sugars, which was specifically tailored to immigrant and US-born adults of Mexican origin. METHODS: Hispanic adults of Mexican origin (n = 326; 36.2 ± 12.1 years) completed a self-administered survey to gather acculturation, self-reported dental experiences and self-care practices (eg brushing, flossing, pain, bleeding gums), and socio-demographic information. The survey included a culturally tailored 22-item Added Sugar Intake Estimate (ASIE) that assessed added sugar intake from processed foods and sugar-sweetened beverages in a semiquantitative food frequency questionnaire format. Linear regression, 2-sample t test, and ANOVA were used to evaluate associations of demographic and dental outcomes with daily added sugar intake. RESULTS: Of the mean total daily added sugar intake (99.6 ± 94.6 g), 36.5 ± 44.4 g was derived from sugar-containing foods and snacks, and 63.1 ± 68.2 g from beverages. Participants who reported greater added sugar intake were more likely to have reported the presence of a toothache in the preceding 12 months, having been prescribed antibiotics for dental reasons, being less likely to floss daily, have reported eating or drinking within 1 hour before bed and have lower psychological acculturation (P < .05 for all). Results were comparable when assessing intake from sugar-containing foods/snacks and sugar-sweetened beverages. CONCLUSIONS: This study confirmed the association between added sugar intake and self-reported dental outcomes among adults of Mexican origin and points to an urgent need to improve dietary behaviours in this population.

Fluoride Use in Health Care Settings: Association with Children's Caries Risk.

Expanded partnership with the medical community is an important strategy for reducing dental caries disparities. The purpose of this study was to assess the relationship between fluoride (F) "in office" (drops/tablets and/or varnish), as prescribed or applied by a health care professional by age 1 y, and 1) caries development and 2) presence of other caries risk factors or mediators (e.g., socioeconomic status). Child-primary caregiver (PCG) pairs ( N = 1,325) were recruited in Indiana, Iowa, and North Carolina as part of a longitudinal cohort study to validate a caries risk tool for primary health care settings. PCGs completed a caries risk questionnaire, while children received caries examinations per the criteria of the International Caries Detection and Assessment System at ages 1, 2.5, and 4 y. Baseline responses regarding children's history of F in office were tested for association with other caries risk variables and caries experience at ages 2.5 and 4 y via generalized estimating equation models applied to logistic regression. The sample was 48% female, and many children (61%) were Medicaid enrolled. The prevalence of cavitated caries lesions increased from 7% at age 2.5 y to 25% by age 4 y. Children who received F in office were likely deemed at higher caries risk and indeed were significantly ( P < 0.01) more likely to develop cavitated caries lesions by ages 2.5 and 4 y, even after F application (odds ratios: 3.5 and 2.3, respectively). Factors significantly associated with receiving F included the following: child being Medicaid enrolled, not having an employed adult in the household, child and PCG often consuming sugary drinks and snacks, and PCG having recent caries experience. Increased F in office from a health care provider by age 1 y was associated with known caries risk factors. Most (69%) children had never been to the dentist, suggesting that risk factors could be alerting medical providers and/or parents, thereby affecting in-office F recommendations. Differences among states could also be related to state-specific F-varnish reimbursement policies (ClinicalTrials.gov NCT01707797).

Susceptibility of partially desalivated rats to erosive tooth wear by calcium-supplemented beverages.

OBJECTIVES: To investigate the susceptibility of partially desalivated rats to erosive tooth wear (ETW); the anti-erosive effect of a calcium-supplemented beverage; and the quantification of ETW by microcomputed tomography (micro-CT). METHODS: The study population consisted of thirty-eight rats, divided into partially desalivated (n = 19) and normal salivary flow (n = 19). They were randomly allocated into three subgroups (n = 6-7): A-diet soda, B-diet soda + calcium, C-water (control). Solutions were provided ad libitum for 28 days, and the rats were euthanized afterwards. Each left hemi-mandible was scanned using micro-CT for enamel volume (three molars) calculation. Visual analysis of photographs of the lingual surface of first molars was performed independently by three blinded examiners. Data were statistically analysed (α = .05). RESULTS: Micro-CT revealed no significant differences between partially desalivated or normal groups. Rats consuming A had more enamel loss than those consuming B or C, which did not differ from each other. For visual analysis, desalivation did not affect ETW. Rats consuming C showed the lowest ETW, followed by B and then A, for both partially desalivated and normal rats. Spearman correlation between the two ETW quantification methods was -.65. CONCLUSIONS: Partial desalivation did not increase ETW. Ca-containing beverage prevented ETW. Micro-CT quantified ETW, although it was not as sensitive as visual analysis.

In vitro performance of near infrared light transillumination at 780-nm and digital radiography for detection of non-cavitated approximal caries.

OBJECTIVES: To evaluate the ability of a Near Infrared Light Transillumination (NILT) device to detect non-cavitated approximal caries lesions; and to compare its performance to Digital Radiography (DR). METHODS: Thirty human extracted premolars (sound to lesions into the outer one-third of dentin) were selected. Lesion depth was confirmed by micro-computed tomography (µ-CT). Teeth were mounted in a custom-made device to simulate approximal contact. DR and NILT (CariVu™, DEXIS, LLC, Hatfield, PA, USA) examinations were performed and repeated by three trained and calibrated examiners. Sensitivity, specificity, area under ROC curve (Az), inter- and intra-class correlation coefficients (ICCs) for each method, and correlation among the methods were determined. RESULTS: ICCs for intra-/inter-examiner agreement were substantial for NILT (0.69/0.64), and moderate for DR (0.52/0.48). Sensitivity/specificity for NILT and DR were 0.68/0.93 and 0.50/0.64, respectively. Az for NILT was 0.81, while for DR it was 0.61. Spearman correlation coefficient with µ-CT for NILT (0.65, p<0.001) demonstrated moderate association, while that of DR suggested no association (0.19, p=0.289). CONCLUSION: Within the limitations of this in vitro study, NILT demonstrated a potential for early approximal caries detection. NILT and DR performed the same regarding the accuracy for non-cavitated approximal caries detection; however, NILT was superior to DR in terms of repeatability, agreement and correlation with µ-CT. CLINICAL SIGNIFICANCE: A commercial version of NILT was recently introduced as a non-irradiative adjunctive caries detection method. It uses near infrared (NIR) light at 780-nm to transilluminate teeth and captures live images from the occlusal surface. This study demonstrates that NILT can be used as an alternative to radiography for non-cavitated approximal caries detection.

Fluoride concentration in saliva and biofilm fluid following the application of three fluoride varnishes.

OBJECTIVE: Most of the commercially available fluoride varnishes (FV) have not been evaluated for their cariostatic properties. Consequently, the aim of this in vivo study was to investigate intra-oral fluoride retention and clearance patterns from three different FV. METHODS: Eighteen subjects (7-11 years) participated in a laboratory analyst-blinded, randomized, crossover study comparing the ability of 5% sodium fluoride varnishes (CavityShield-CS, Enamel Pro-EP, Vanish-V) to enhance fluoride concentrations in biofilm fluid, centrifuged and whole saliva over a period of 48h after a single FV application. RESULTS: Similar fluoride concentration×time patterns were noted for all investigated FV and studied variables, with the highest fluoride concentrations observed for the first biological sample collected after FV application (30min). Mean±SE (area under fluoride clearance curve) values were (µg F/g or ml×min): biofilm fluid - CS (472±191), EP (423±75),V (1264±279); centrifuged saliva - CS (42±7), EP (19±3),V (41±8); whole saliva - CS (68±11), EP (64±10),V (60±7).V delivered more fluoride to biofilm fluid than CS (p=0.0116) and EP (p=0.0065), which did not differ (p=0.27). For centrifuged saliva, CS and V were not significantly different (p=0.86), but resulted in higher fluoride retention than EP (p<0.0008). No significant differences among FV were observed for whole saliva (p=0.79). CONCLUSION: The present study has shown that FV vary in their ability to deliver fluoride intra-orally potentially related to formulation differences. To what extent the present findings relate to clinical efficacy remains, however, to be determined. CLINICAL SIGNIFICANCE: Clinical research that investigates fluoride release patterns into saliva and biofilm fluid from different FV products is insufficient. More research is needed to investigate different FV formulations for their efficacy in order to help clinicians make better evidence based treatment choices.

Dental Surface Texture Characterization Based on Erosive Tooth Wear Processes.

The differential diagnosis of dental wear lesions affects their clinical management. We hypothesized that surface texture parameters can differentiate simulated erosion, abrasion, and erosion-abrasion lesions on human enamel and dentin. This in vitro study comprised 2 parts (both factorial 4 × 2), with 4 lesion types (erosion, abrasion, erosion-abrasion, and sound [no lesion; control]) and 2 substrates (enamel and dentin). Flattened/polished dental specimens were used in part 1, whereas natural dental surfaces were used in part 2. Testing surfaces were evaluated in blind conditions, using average surface roughness (Sa) and the following scale-sensitive fractal analysis parameters: area-scale fractal complexity (Asfc), exact proportion length-scale anisotropy of relief (eplsar), scale of maximum complexity (Smc), and textural fill volume (Tfv). Two-way analyses of variance, followed by Fisher's protected least significant difference tests (α = 0.05), were used to evaluate the effects of lesion and substrate. Classification trees were constructed to verify the strength of potential associations of the tested parameters. In part 1,Asfc, Sa, and Tfv were able to differentiate erosion and erosion-abrasion lesions from the sound (no lesion) control in both substrates; only Asfc differentiated erosion and erosion-abrasion enamel lesions (allP< 0.05). The best association of parameters correctly classified up to 84% and 94% of the lesions on enamel and dentin, respectively. In part 2, only Asfc differentiated erosion and erosion-abrasion lesions from the sound (no lesion) control in both substrates, whereas eplsar was able to differentiate erosion from erosion-abrasion (allP< 0.05). The association of parameters correctly classified up to 81% and 91% of the lesions in enamel and dentin, respectively.Asfc, Sa, and Tfv were able to differentiate erosion and erosion-abrasion lesions, despite their complicated surface textures. The association of parameters improved the differentiation of lesions for both enamel and dentin in polished or natural surfaces.

White diet: is it necessary during tooth whitening?

Patients are sometimes blamed for a reduced effect of bleaching when they do not adhere to a dentist's prescribed white diet. This study aimed to determine whether a white diet is necessary by evaluating the effects of coffee, tea, wine, and dark fruits on the potential tooth whitening during the bleaching process. Each of the effects of discoloration was categorized as "yes" or "no" based on a patient questionnaire. Data from five published studies were included in the analyses. Outcomes were based on the color change between baseline and the end of bleaching. The relationships between color changes were measured subjectively and objectively. A nonwhite diet was not significantly associated with less tooth whitening, and there was only a weak positive association between tooth whitening and diet for subjects who drank large amounts of coffee/tea.

Bone marrow fat is increased in chronic kidney disease by magnetic resonance spectroscopy.

UNLABELLED: In aging, the bone marrow fills with fat and this may lead to higher fracture risk. We show that a bone marrow fat measurement by magnetic resonance spectroscopy (MRS), a newer technique not previously studied in chronic kidney disease (CKD), is useful and reproducible. CKD patients have significantly higher bone marrow fat than healthy adults. INTRODUCTION: Renal osteodystrophy leads to increased morbidity and mortality in patients with CKD. Traditional bone biopsy histomorphometry is used to study abnormalities in CKD, but the bone marrow, the source of osteoblasts, has not been well characterized in patients with CKD. METHODS: To determine the repeatability of bone marrow fat fraction assessment by MRS and water-fat imaging (WFI) at four sites in patients with CKD, testing was performed to determine the coefficients of reproducibility and intraclass coefficients (ICCs). We further determined if this noninvasive technique could be used to determine if there are differences in the percent bone marrow fat in patients with CKD compared to matched controls using paired t tests. RESULTS: The mean age of subjects with CKD was 59.8 ± 7.2 years, and the mean eGFR was 24 ± 8 ml/min. MRS showed good reproducibility at all sites in subjects with CKD and controls, with a coefficient of reproducibilities ranging from 2.4 to 13 %. MRS and WFI assessment of bone marrow fat showed moderate to strong agreement (ICC 0.6-0.7) at the lumbar spine, with poorer agreement at the iliac crest and no agreement at the tibia. The mean percent bone marrow fat at L2-L4 was 13.8 % (95 % CI 8.3-19.7) higher in CKD versus controls (p < 0.05). CONCLUSIONS: MRS is a useful and reproducible technique to study bone marrow fat in CKD. Patients with CKD have significantly higher bone marrow fat than healthy adults; the relationship with bone changes requires further analyses.

A Potential Biofilm Metabolite Signature for Caries Activity - A Pilot Clinical Study.

BACKGROUND: This study's aim was to compare the dental biofilm metabolite-profile of caries-active (N=11) or caries-free (N=4) children by gas chromatography-mass spectrometry (GC/MS) analyses. METHODS: Samples collected after overnight fasting, with or without a previous glucose rinse, were combined for each child based on the caries status of the site, re-suspended in ethanol and analyzed by GC/MS. RESULTS: Biofilm from caries-active sites exhibited a different chromatographic profile compared to caries-free sites. Qualitative and quantitative analysis suggested a special cluster of branched alcohols and esters present at substantially higher intensity in biofilms of caries-active sites. CONCLUSIONS: This pilot study indicates that there are metabolites present in the biofilm which have the potential to provide a characteristic metabolomics signature for caries activity.

Bonding ability of paste-paste glass ionomer systems to tooth structure: in vitro studies.

This study investigated the effect of nonrinse conditioners (ie, Ketac Nano Primer [KNP] and GC Self Conditioner [SC]) used as substrate pretreatment and their respective paste-paste resin-modified glass-ionomer cement (RMGIC) (ie, Ketac Nano [KN] and Fuji Filling LC [FF]) on microtensile bond strength to dentin and marginal sealing when compared with traditional RMGIC (ie, Photac Fil [PF] and Fuji II LC [FII]) used in association with polyacrylic acid (ie, Ketac Cavity Conditioner [KC] and GC Cavity Conditioner [CC]). A total of 192 extracted human molars were allocated into eight groups: KNP-KN, KC-KN, KNP-PF, KC-PF, SC-FF, CC-FF, SC-FII, and CC-FII. For microtensile bond strength, the teeth were sectioned to expose occlusal dentin and restored according to the group. After 24 hours the teeth were cut to yield nine beams per tooth (±0.8 mm(2)). Testing was done using a universal testing machine followed by failure mode classification. For microleakage testing, standardized cavity preparations were made on the buccal cementoenamel junction and restored according to the group. The teeth were thermocycled (500 cycles, 8°C to 48°C), sealed, immersed in methylene blue for 24 hours, and then assessed for microleakage using a stereomicroscope. Microtensile bond strengths in megapascals (mean±SE) were KNP-KN: 14.9 ± 1.6, KC-KN: 17.2 ± 1.5, KNP-PF: 31.2 ± 1.6, KC-PF: 26.2 ± 1.2, SC-FF: 23.6 ± 1.5, SC-FII: 31.2 ± 1.5, and CC-FII: 21.9 ± 1.5. Cervical margins showed more microleakage compared with occlusal margins. Overall, the use of nonrinse conditioners in association with traditional RMGICs demonstrated superior microtensile bond strengths to dentin when compared with the paste-paste RMGICs. Meanwhile, the association between polyacrylic acid (CC) and a traditional RMGIC (FII) led to the least microleakage for cervical locations when compared with all other groups.