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.

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.

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).

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.

The effects of salivas on occlusal forces.

Contacting surfaces of opposing teeth produce friction that, when altered, changes the contact force direction and/or magnitude. As friction can be influenced by several factors, including lubrication and the contacting materials, the aim of this study was to measure the occlusal load alterations experienced by teeth with the introduction of different salivas and dental restorative materials. Pairs of molar teeth were set into occlusion with a weighted maxillary tooth mounted onto a vertical sliding assembly and the mandibular tooth supported by a load cell. The load components on the mandibular tooth were measured with three opposing pairs of dental restorative materials (plastic denture, all-ceramic and stainless steel), four (human and three artificial) salivas and 16 occlusal configurations. All lateral force component measurements were significantly different (P < 0·0001) from the dry (control) surface regardless of the crown material or occlusal configuration, while the effects of the artificial salivas compared to each other and to human saliva depended on the crown material.

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.

A defined-multispecies microbial model for studying enamel caries development.

The aims of this study were to describe and validate an in vitro multispecies microbial biofilm model for caries development by evaluating the effects of varying medium concentration of sucrose (0.5 and 1.0%) and fluoride (0.4, 0.8 and 1.0 ppm F) in study 1, and calcium (1.0 and 2.0 mM Ca) in study 2. Defined-multispecies biofilms, formed by Lactobacillus casei, Streptococcus mutans, S. salivarius and S. sanguinis, were grown on the surface of salivary-pellicle-coated enamel slabs, with known baseline surface hardness; growth medium was changed daily. Counts of viable cells on biofilms and the percentage of surface microhardness change (%SMC), lesion depth (LD) and integrated mineral loss (IML) on enamel slabs were assessed after 4 days of biofilm formation under the tested conditions. Counts of viable cells on biofilms were significantly affected by sucrose, fluoride and calcium concentrations (p < 0.05). There was a decrease in %SMC in response to increased fluoride and calcium concentrations (p < 0.001). Lower IML (p < 0.001) and LD (p < 0.05) were found in the presence of 0.8 and 1.0 ppm F. A negative correlation was found between the response variables (%SMC, LD and IML) and fluoride and calcium concentrations. The results suggest that the microbial caries model developed was able to show distinct levels of caries inhibition in response to fluoride and calcium concentrations, corroborating clinical observations. An effect of sucrose concentration on caries development was found only in the presence of the lowest fluoride concentration.

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.

In situ evaluation of the erosive potential of orange juice modified by food additives.

The aim of this study was to evaluate the erosive potential of orange juice modified with food-approved additives: 0.4 g/l of calcium (Ca) from calcium lactate pentahydrate, 0.2 g/l of linear sodium polyphosphate (LPP) or their combination (Ca+LPP) were added to a commercially available orange juice (negative control, C-). A commercially available calcium-modified orange juice (1.6 g/l of calcium) was the positive control (C+). These juices were tested using a short-term erosion in situ model, consisting of a five-phase, single-blind crossover clinical trial involving 10 subjects. In each phase, subjects inserted custom-made palatal appliances containing 8 bovine enamel specimens in the mouth and performed erosive challenges for a total of 0 (control), 10, 20, and 30 min. Two specimens were randomly removed from the appliances after each challenge period. Enamel surface microhardness was measured before and after the clinical phase and the percentage of surface microhardness change (%SMC) was determined. Before the procedures, in each phase, the subjects performed a taste test, where the juice assigned to that phase was blindly compared to C-. Overall, C+ showed the lowest %SMC, being the least erosive solution (p < 0.05), followed by Ca+LPP and Ca, which did not differ from each other (p > 0.05). LPP and C- were the most erosive solutions (p < 0.05). Taste differences were higher for C+ (5/10 subjects) and Ca (4/10 subjects), but detectable in all groups, including C- (2/10 subjects). Calcium reduced the erosive potential of the orange juice, while no protection was observed for LPP.

Do occlusal contact detection products alter the occlusion?

Clinicians rely on occlusal contact detection products to identify high contacts and to equilibrate occlusions. Concerns about these products have stimulated numerous investigations into marking reproducibility, accuracy and interpretation, but none have looked at their effects on the occlusion itself. The aim of this study was to assess whether these products alter the occlusion that they purport to measure by determining whether there are differences in the forces and moments experienced by occluding teeth with and without their presence. A matched pair of IPN Portrait 33° molar denture teeth was placed into occlusion with the mandibular tooth supported by a load sensor and the maxillary tooth mounted onto a vertically sliding assembly with a total weight of 15·1N. The three-dimensional force and moment components on the mandibular tooth were measured when the teeth were in direct crown-crown contact (control) and with the products in place. All six products, (Accufilm I, Accufilm II, Hanel Articulating Silk, Rudischhauser Thick and Thin, and T-scan) showed significant (P<0·05) differences in forces and moments from control.

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.

In situ fluoride response of caries lesions with different mineral distributions at baseline.

The present in situ study investigated the fluoride response of caries lesions with similar mineral loss but two distinct mineral distributions (low- and high-'R', calculated as the ratio of mineral loss to lesion depth). Sixteen subjects wore eight gauze-covered enamel specimens with preformed lesions placed buccally on their mandibular partial dentures for periods up to 4 weeks. The participants brushed twice daily for 1 min with an 1,100 ppm F (as NaF) dentifrice. After 3 and 4 weeks, specimens were retrieved and analyzed microradiographically (TMR) and by quantitative light fluorescence (QLF). TMR results revealed that low- and high-R lesions showed opposite behaviors - low-R lesions further demineralized, whereas high-R lesions exhibited some remineralization. In comparison, lesion depth increased in low-R, but remained unchanged in high-R lesions; R decreased in both, but more in high-R lesions; mineral density at the lesion surface remained unchanged in low-R, but increased in high-R lesions. Differences in mineral loss between lesion types increased further between 3 and 4 weeks. QLF did not mirror TMR results as low-R lesions were found to remineralize, whereas high-R lesions remained unchanged. It is likely that low-R lesions differ from high-R lesions chemically and microstructurally; therefore rendering low-R lesion more susceptible to further dissolution. During lesion formation, low-R in contrast to high-R lesions may not lose all of the solubility-determining impurities such as magnesium and carbonate, which can reprecipitate again in different mineral phases within the lesion. In conclusion, mineral distribution at baseline directly impacts in situ lesion response to fluoride.

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.

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.

Preliminary study to establish a relationship between tactile sensation and surface roughness.

This study evaluated the ability of tactile sensations to distinguish roughness. Five examiners experienced in visual examination participated. Tactile sensation was assessed by 3 standard references, the average roughnesses 0.49, 0.92 and 1.54 mum. The examiners evaluated the roughness using 2 different ends of sharp explorers (TU 17 SE and 23 SE), each with 2 different handles (Standard Handle and No. 6 Handle-Satin Steel), and 1 WHO probe using a 5-point response score. The examiners performed 3 evaluations to establish repeatability. Using the 23 SE explorer with the steel handle was the best option to distinguish between 3 roughnesses (p < 0.05). The intraexaminer intraclass correlation coefficients (ICC) were between 0.90 and 0.98, but the interexaminer ICC were only between 0 and 0.04, indicating that, although trained examiners could repeat their own scores, they were not consistent with each other in grading roughness.

Metabolic syndrome attenuates effect of chronic kidney disease on prevalence of coronary disease in men referred for stress imaging study.

BACKGROUND: Metabolic syndrome (MS) and chronic kidney disease (CKD) are both strongly associated with coronary artery disease (CAD). Components of MS also cause CKD. The incremental effect of CKD on CAD prevalence in MS patients referred for stress imaging studies is unknown. METHODS: From January to December 2005, consecutive subjects referred for a stress imaging study were prospectively enrolled. CAD was defined as fixed or reversible defects on nuclear imaging and as resting or stress-induced wall motion abnormalities on echocardiography. MS was defined using NCEP-ATP III criteria. CKD definition was based on calculated glomerular filtration rate. The independent effect of CKD on stress results was assessed using multiple variable logistic regression. Stepwise model selection was used for variable reduction, and areas under the receiver operating characteristic curves (ROC) were calculated. RESULTS: Of 1,122 patients enrolled (mean age 61.4 years, 97% male), 535 (47%) had MS. Among MS patients, 156/535 (29%) had CKD while 116/587 (19%) subjects without MS had CKD. Subjects with CKD were older (p < 0.001) in subjects with and without MS. The presence of CKD affected prevalence of CAD in the non-MS group only, almost doubling it (20% vs. 38%, p < 0.001). Further, using the ordered nature of the 5 CKD stages, worsening severity of CKD had greater prevalence of CAD, in non-MS subjects only (p < 0.001). CONCLUSIONS: MS attenuates the effect of CKD on CAD prevalence, regardless of CKD severity. CKD almost doubles the prevalence of CAD in non-MS subjects. CKD severity is associated with greater CAD burden in the non-MS group.

Influence of fluoride availability of dentifrices on eroded enamel remineralization in situ.

Remineralization of eroded enamel by dentifrices containing similar sources/concentrations of fluoride was investigated in situ. Fifty-three subjects completed a double-blind crossover study with 3 randomly assigned dentifrice treatments: placebo (0 ppm F, PD); reference (1,450 ppm NaF, RD) and test (1,450 ppm NaF + 5% KNO(3), TD). Fluoride availability for each dentifrice was analyzed in vitro by standard tests (1-min fluoride release rate and enamel fluoride uptake). The subjects wore palatal appliances holding bovine enamel specimens previously eroded in vitro. Surface microhardness was determined before and after the in vitro erosive challenge, after in situ remineralization and after a second in vitro erosive challenge. ANOVA and pairwise comparisons were performed (alpha=0.05). TD was superior to RD in the fluoride release tests, but similar to RD in the enamel fluoride uptake test. The mean percent surface microhardness recovery was 21.9 (standard deviation 8.0) for PD, 28.6 (8.0) for RD and 36.0 (8.0) for TD. The mean percent relative erosion resistance change was -58.8 (12.7) for PD, -31.3 (12.7) for RD and -27.3 (12.6) for TD. Both fluoride-containing dentifrices provided superior remineralization (p<0.001) and erosion resistance (p<0.001) compared to PD. The percent surface microhardness recovery demonstrated by the TD was significantly greater than for the RD (p<0.001). There was no significant difference (p=0.073) between TD and RD in relative resistance to further erosive challenge. The results suggest that fluoride availability may be different in dentifrices with similar sources/concentrations of fluoride, providing different levels of remineralization of eroded enamel.

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.

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.

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).