A social-ecological examination of sleep among Airmen in technical training.

Inadequate sleep is an on-going risk to the health and mission readiness of U.S. Armed Forces, with estimates of sleep problems high above U.S. civilian populations. Intervening early in the career of active duty Air Force personnel (or "Airmen") with education and the establishment of healthy behaviors may prevent short and long term-detriments of sleep problems. This paper describes the results of a qualitative study seeking to understand the facilitators and barriers to achieving good sleep in a technical training school during the first year of entry into the United States Air Force. Using the social ecological framework and content analysis, three focus groups with Airmen were conducted to explore themes at the individual, social, environmental, and organizational/policy level. Overall, results indicated a cohort motivated to achieve good sleep, and also struggling with a number of barriers across each level. This paper highlights opportunities for population health interventions during technical training aimed at supporting Airmen in developing healthy sleep behaviors early in the course of their career.

Evaluating capacity at three government referral hospital emergency units in the kingdom of Eswatini using the WHO Hospital Emergency Unit Assessment Tool.

BACKGROUND: The Kingdom of Eswatini, a lower-middle income nation of 1.45 million in southern Africa, has recently identified emergency care as a key strategy to respond to the national disease burden. We aimed to evaluate the current capacity of hospital emergency care areas using the WHO Hospital Emergency Unit Assessment Tool (HEAT) at government referral hospitals in Eswatini. METHODS: We conducted a cross-sectional study of three government referral hospital emergency care areas using HEAT in May 2018. This standardised tool assists healthcare facilities to assess the emergency care delivery capacity in facilities and support in identifying gaps and targeting interventions to strengthen care delivery within emergency care areas. Senior-level emergency care area employees, including senior medical officers and nurse matrons, were interviewed using the HEAT. RESULTS: All sites provided some level of emergency care 24 h a day, 7 days a week, though most had multiple entry points for emergency care. Only one facility had a dedicated area for receiving emergencies and a dedicated resuscitation area; two had triage areas. Facilities had limited capacity to perform signal functions (life-saving procedures that require both skills and resources). Commonly reported barriers included training deficits and lack of access to supplies, medications, and equipment. Sites also lacked formal clinical management and process protocols (such as triage and clinical protocols). CONCLUSIONS: The HEAT highlighted strengths and weaknesses of emergency care delivery within hospitals in Eswatini and identified specific causes of these system and service gaps. In order to improve emergency care outcomes, multiple interventions are needed, including training opportunities, improvement in supply chains, and implementation of clinical and process protocols for emergency care areas. We hope that these findings will allow hospital administrators and planners to develop effective change management plans.

Superimposition of sequential scans to measure erosion on unpolished and curved human enamel.

OBJECTIVES: To determine if superimposition of sequential scans can discriminate between different fluorides at step heights less than 5 µm on natural human enamel surfaces. MATERIALS AND METHODS: Natural, unpolished, human enamel specimens (n = 60) were randomly assigned to one of three pre-treatment toothpaste slurries with a calcium silicate/fluoride, fluoride-only and a control. Baseline and post treatment scans, from a non-contacting profilometer with a 0.01 µm z-axis and <1 µm lateral scanning resolution were imported into superimposition software to define change in mean 3D step height and surface roughness following erosion in 0.3% citric acid for 15 min. Statistical analysis conducted with two-way repeated measures ANOVA and post-hoc Tukey's multiple comparisons. RESULTS: Confidence and resolution of superimposition and subtraction of repeated profiles from unpolished enamel revealed accuracy within 1-2 µm. The technique was able to discriminate between the fluorides demonstrating statistical differences in mean (SD) 3D step height (µm) of 1.96 (0.40) and 2.75 (0.49) (p = 0.0024). There was a statistically significant increase in surface roughness for all groups after 15 min erosion compared to baseline. But no statistically significant difference between the interventions after 15 min erosion but there was compared to no fluoride (p = 0.006). CONCLUSION: Superimposition and subtraction of profiles could discriminate between fluoride interventions, which showed statistical differences in enamel loss differences less than 3 µm. CLINICAL SIGNIFICANCE: This erosion model and data analysis workflow was able to distinguish differences between scans of 3 µm on unpolished enamel following the interaction with fluoride.

The impact of tooth colour on the perceptions of age and social judgements.

OBJECTIVE: Psychological research has established that the presence of dental anomalies negatively impact social judgements. This study sought to determine the effects of tooth colour on the subjective ratings of social judgements in a group of Caucasian adults. METHODS: A cross sectional experimental analogue design comprised fifty Caucasian adults: 25 women and 25 men. A total of 54 digitally modified photographs of Caucasian males and females (darkened, natural, whitened teeth) were evaluated. All participants evaluated each of the images on 12 characteristics: popularity, friendliness, social life, success, graduation, happiness, intelligence, perceived age, introversion/extraversion, self-confidence, attractiveness and satisfaction with the tooth shade. Analysis of variance (ANOVA) was used to compare ratings. RESULTS: Participants associated darkened teeth with poorer subjective ratings, with the highest ratings been given to whitened teeth, and natural teeth being intermediate. These trends were similar across all participant age groups and gender. Further, the gender and age groups of the images had a significant effect on the appraisals. Faces of younger models received higher ratings than the faces of older models and female images were rated higher than the males. CONCLUSION: In the absence of other information, tooth colour exerts an influence upon the appraisals made in social situations. It appears that whitened tooth appearance is preferred to natural tooth appearance, irrespective of age and gender of the judge. The faces with more whitened dentition are perceived to be younger across all age groups and gender of the judges. Participants dissatisfied with their own tooth shade drew out more stereotypic behaviour. CLINICAL SIGNIFICANCE STATEMENT: This research used standardised tooth colour as a basis to investigate perceived age and social functioning. As clinicians face daily challenges to achieve patient satisfaction with respect to dental aesthetics, standardizing the colour may enhance the patients' satisfaction. Further, participants dissatisfied with their own tooth shade drew out more stereotypic behaviour. The whitened dentition may impair the psychological well-being of the individuals and is probably a reason for the increasing demand for cosmetic dental procedures. These results may be instructive for the development of a psycho-educational intervention to prevent any unrealistic expectations.

The measurement of enamel wear by four toothpastes.

OBJECTIVES: To determine the enamel abrasivity of three whitening toothpastes and a silica toothpaste and to measure the brushing forces used. METHODS: Polished human enamel blocks were indented with a Knoop diamond and attached to dentures of adult volunteers. The blocks were brushed ex vivo, twice per day with either a whitening toothpaste containing Perlite (White System), a commercial whitening toothpaste (A and B) or a silica toothpaste. After four and twelve-weeks, one block per subject was removed and the Knoop indent remeasured. From the changes in the indent length, the amount of enamel wear was calculated. RESULTS: The mean enamel wear (sd) for White System, silica toothpaste, whitening toothpaste A and B after four-weeks was 0.14 (0.15), 0.09 (0.16), 0.14 (0.12) and 0.89 (0.93) and after twelve-weeks was 0.24 (0.21), 0.37 (0.73), 0.36 (0.52) and 1.04 (0.98) microm respectively. After four-weeks, the differences in enamel wear between whitening toothpaste B and all other toothpastes were of statistical significance (p < 0.003), but not after twelve-weeks. The mean ex vivo normal brushing force (sd) was 2.67 (1.33) N. CONCLUSIONS: All three whitening toothpastes did not give significantly more enamel wear than a silica toothpaste after twelve-weeks in situ with ex vivo brushing.

In vitro evaluation of the early erosive lesion in polished and natural human enamel.

OBJECTIVE: This study evaluated the capability of profilometry, microhardness, Optical Coherence Tomography (OCT) and Tandem Scanning Confocal Microscopy (TSM) in characterising the early erosive lesion in polished and natural human enamel in vitro. METHODS: Polished (n=60) and natural (n=60) human enamel surfaces, were immersed and agitated in 0.3% citric acid erosion at 0s, 10s, 30s, 60s, 120s, and 300s (n=10). Changes in the surface were measured with 3D-step height change (µm), surface roughness (µm), surface microhardness (KHN), and images were assessed qualitatively with OCT and TSM. RESULTS: Mean (SD) 3D-step height change (µm) was measurable for polished enamel at: 60s (0.24±0.1), 120s (1.16±0.71), 300s (2.01±0.47; p<0.05); a step height change was not detectable on acid challenged natural enamel surfaces. Mean (SD) surface roughness (µm) of polished enamel was detected at 10s (0.270±0.013; p<0.05) and all erosion periods; and in natural enamel detected after 120s (0.830±0.125) and 300s (0.800±0.140; p<0.005). Polished enamel Mean (SD) microhardness (KHN) statistically significantly decreased at all time points (p<0.001); this was unmeasurable for natural enamel. Qualitative image analysis of both surface types indicated erosive change at the surface level, with progression after increasing erosion time. SIGNIFICANCE: The early erosive lesion in polished enamel could be characterised quantitatively surface roughness and microhardness and qualitatively using OCT and TSM; whilst in natural enamel only surface roughness could be utilised. Further investigation of early erosion in natural enamel is required to develop new more clinically relevant models.

The effect of carbamide peroxide treatment on metal ion release from dental amalgam.

OBJECTIVES: There is concern that hydrogen peroxide generated by tooth bleaching agents may cause enhanced metal ion release (including mercury) from dental amalgam following contact. The aim of this in vitro study was therefore to investigate the effect of a carbamide peroxide (CP) based tooth bleaching gel on metal ion release from dental amalgam. METHODS: Dental amalgam discs were prepared according to the manufacturers' instructions. These were treated with either a 10% carbamide peroxide (CP) gel or a 0% CP gel for 24h. Discs were carefully wiped with cotton wool before immersion in distilled water (20 ml) for 24h at 37 degrees C. Following immersion, water samples were taken for metal ion release determination (Ag, Cu, Hg and Sn) using inductively coupled plasma mass spectrometry methods. The specimens were further evaluated for surface changes using scanning electron microscopy (SEM) and Talysurf surface roughness measurements. RESULTS: The differences in concentration of metal ions released after treatment with the 10% CP gel and a placebo gel treatment were not statistically significant (p>0.05). For example, mercury release following treatment with the 10% CP gel and the 0% CP gel was found to be 1.17(0.5) and 0.57(0.1)microgcm(-2), respectively. Roughness measurements for samples treated with the 10% CP gel and 0% CP gel were 2.23(0.47) and 1.74(0.16)microm, respectively, again showing no significant difference between groups (p>0.05). SEM images of the amalgam surfaces showed no apparent differences between treatments. SIGNIFICANCE: Treatment with a 10% CP gel did not significantly enhance subsequent metal ion release from dental amalgams compared to a control gel, contradicting previously published studies.

The measurement in vitro of enamel and dentine wear by toothpastes of different abrasivity.

OBJECTIVES: To investigate the in vitro enamel and dentine wear by toothpastes with a range of Relative Dentine Abrasivity (RDA) and Relative Enamel Abrasivity (REA) values. METHODS: Human enamel/dentine (approximately 50:50) blocks (approximately 4 x 4 mm) were polished and the enamel indented with four Knoop indents. The step across the enamel-dentine junction was measured by interference microscopy. Specimens were brushed in vitro with toothpastes with a range of RDA/REA values using a flat trim toothbrush mounted in a Wira brushing machine for 360 s and a load of 375 g. After brushing the Knoop indent length and the enamel-dentine step were remeasured and the amount of wear to the enamel and dentine was calculated. RESULTS: The mean enamel wear ranged from 0.05 to 0.40 microns, with the highest wear for the highest REA product. The mean dentine wear for all toothpaste products tested was positively correlated with RDA value (R2 = 0.897). The correlation was further improved if median wear values were used (R2 = 0.930). CONCLUSIONS: This study has demonstrated a rapid technique for the simultaneous investigation of the abrasive wear of toothpaste on enamel and dentine. There was a good correlation between median dentine wear and RDA values.

Abrasion of human enamel and dentine caused by toothpastes of differing abrasivity determined using an in situ wear model.

OBJECTIVES: To determine the rates of enamel and dentine wear in situ during tooth brushing with a range of five toothpastes of differing RDA and REA values. METHODS: Enamel/dentine inserts were placed in the buccal aspects of full upper dentures of human volunteers. Enamel wear was determined by change in Knoop indent length and dentine wear was determined from the enamel-dentine step height, measured using optical profilometry. RESULTS: Significant differences between the test products were found for both enamel and dentine (p < 0.05). However for the conventional toothpastes the rate of wear was similar and differences between the products were not generally statistically significant for either enamel or dentine, despite the fact that their RDA values differed by more than a factor of two. The rate of wear was found to decrease throughout the duration of the study. CONCLUSIONS: The study demonstrated that the methodology used is capable of assessing enamel and dentine wear in situ within a relatively short period of time. The data suggest that whilst in vitro tests have value in understanding differences in abrasivity between products, they cannot be used to predict in vivo effects.

The measurement of enamel and dentine abrasion by tooth whitening products using an in situ model.

OBJECTIVES: To determine the enamel and dentine wear of two whitening toothpastes using an in situ model with ex vivo brushing. METHODS: Human enamel/dentine (approximately 50:50) blocks (approximately 4 x 4mm) were placed in the upper buccal aspects of full or partial dentures of a group of 25 subjects. Subjects brushed the specimens ex vivo with either a calcium carbonate/perlite or silica containing whitening toothpaste under exaggerated conditions as compared to normal for 30 s, twice per day. Specimens were removed after 4, 8 and 12 weeks and the wear to the enamel and dentine was determined. Enamel wear was determined by change in Knoop indent length and dentine wear was determined from the enamel-dentine step height, measured using optical profilometry. RESULTS: The mean wear after 12 weeks was for enamel 0.27 and 0.19 microns, and for dentine 34.3 and 61.1 microns, for the calcium carbonate/perlite and silica toothpastes respectively. There were no significant differences between products after 12 weeks. The rate of wear was found to decrease throughout the duration of the study. CONCLUSION: There were no significant differences between the two whitening toothpastes in terms of enamel and dentine wear after 12 weeks brushing.

In vitro efficacy of a whitening toothpaste containing calcium carbonate and perlite.

OBJECTIVES: The studies described in this paper aimed to assess the stain removal efficacy, fluoride efficacy and abrasivity to enamel and dentine of a new whitening toothpaste containing calcium carbonate and perlite, using appropriate in vitro models. METHODS: Stain removal efficacy was assessed using the pellicle cleaning ratio (PCR) method. Fluoride efficacy was assessed using remineralisation, demineralisation and fluoride-uptake methods. Abrasivity was assessed using an enamel and dentine wear method. RESULTS: The results showed that the new whitening toothpaste was able to remove extrinsic tooth stain more effectively than three commercially available toothpaste formulations. The fluoride efficacy was superior to a non-fluoridated control and was not significantly different to a clinically tested fluoride-containing toothpaste. The abrasivity data showed that the calcium carbonate/perlite toothpaste is no more abrasive to enamel or dentine than two other commercially available whitening toothpastes. CONCLUSIONS: The studies show that the new whitening toothpaste is effective in extrinsic stain removal, has an efficacious fluoride source and does not have an undue degree of abrasivity to enamel or dentine compared to other relevant commercially available products.

The flow cytometry-defined light chain cytoplasmic immunoglobulin index and an associated 12-gene expression signature are independent prognostic factors in multiple myeloma.

As part of Total Therapy (TT) 3b, baseline marrow aspirates were subjected to two-color flow cytometry of nuclear DNA content and cytoplasmic immunoglobulin (DNA/CIG) as well as plasma cell gene expression profiling (GEP). DNA/CIG-derived parameters, GEP and standard clinical variables were examined for their effects on overall survival (OS) and progression-free survival (PFS). Among DNA/CIG parameters, the percentage of the light chain-restricted (LCR) cells and their cytoplasmic immunoglobulin index (CIg) were linked to poor outcome. In the absence of GEP data, low CIg <2.8, albumin <3.5 g/dl and age ⩾65 years were significantly associated with inferior OS and PFS. When GEP information was included, low CIg survived the model along with GEP70-defined high risk and low albumin. Low CIg was linked to beta-2-microglobulin >5.5 mg/l, a percentage of LCR cells exceeding 50%, C-reactive protein ⩾8 mg/l and GEP-derived high centrosome index. Further analysis revealed an association of low CIg with 12 gene probes implicated in cell cycle regulation, differentiation and drug transportation from which a risk score was developed in TT3b that held prognostic significance also in TT3a, TT2 and HOVON trials, thus validating its general applicability. Low CIg is a powerful new prognostic variable and has identified potentially drug-able targets.

Effect of toothpaste with natural calcium carbonate/perlite on extrinsic tooth stain.

OBJECTIVE: The current study was designed to determine the effect of natural calcium carbonate toothpaste containing Perlite and microgranules (Whitening toothpaste) on extrinsic tooth stain compared to a standard commercial toothpaste formulation with precipitated calcium carbonate (PCC) as abrasive and a commercial toothpaste with dicalcium phosphate dihydrate (DCPD) as abrasive. METHODS: The toothpastes were evaluated in a double blind, three-cell, stratified (tobacco use; baseline tooth stain level), parallel group design study involving 600 subjects with extrinsic tooth stain. Subjects brushed twice daily with their allocated toothpaste for four weeks. Extrinsic tooth stain was measured using the Macpherson modification of the Lobene stain index. RESULTS: ANCOVA showed significant differences between toothpastes (p=0.037). Subsequent multiple comparisons using pairwise t-tests, showed the Whitening toothpaste to be superior to the DCPD toothpaste (p=0.014) and the PCC toothpaste (p=0.067). When a Box-Cox transformation was made to the data (y0.6) to improve normality, these two differences were more accurately estimated at p=0.004 and p=0.03 respectively. CONCLUSION: The Whitening toothpaste has been shown to be significantly more effective in tooth stain removal than the two standard commercial toothpaste formulations.

Tricalcium silicate induced mineralization for occlusion of dentinal tubules.

BACKGROUND: The aim of this study was to evaluate the dentinal tubule occluding ability of tricalcium silicate (Ca(3) SiO(5) or C(3) S) in vitro. METHODS: Dentine discs were prepared from extracted caries-free human third molars and etched with 0.02 M citric acid (pH 4) for 3 minutes in order to produce patent dentinal tubules. Tricalcium silicate pastes of different viscosities were applied to the surface of the dentine specimens for 3 minutes and then removed with a swab followed by deionized water rinse. The dentine specimens were immersed in artificial saliva for 7 days. The tubule occlusion, sealing depth and chemical composition of the dentine specimens and bonding force between the dentine matrix and mineralized layer were evaluated by scanning electron microscopy, energy dispersion X-ray spectroscopy, X-ray diffraction analysis and a nanoscratch test. RESULTS: A homogeneous layer of mineral crystals was precipitated onto the dentine surface and caused significant occlusion of the dentinal tubules. The dentine permeability and sealing depth of the C(3) S increased with the decrease of viscosity of the paste. With a proper viscosity of C(3) S pastes, the interface between the mineralized layer and the dentine matrix bonded well. CONCLUSIONS: This study suggests that C(3) S may be an effective agent for the treatment of dentine hypersensitivity.

Comparison of a conventional and modified tooth stain index.

OBJECTIVES: To evaluate a modified tooth stain index and determine the effect of dietary factors on stain formation. METHODS: At baseline, 182 adult volunteers were given a full oral prophylaxis followed by stain assessment using a modification of the Lobene index. This involved assigning separate scores to the mesial (M) and distal (D) sites of each tooth, in addition to the standard gingival area (G) and tooth body (B). For each site, stain intensity and areas were scored. The sum of (intensity X area) scores was calculated for all sites (GBMD-value) and for the gingival and body sites only (GB-value). The subjects used a standard abrasive dentifrice and a soft toothbrush for 6 weeks. RESULTS: Stain was reassessed and the average increase in GBMD-value was 20.9 (sd=9.9) (buccal aspect) and 29.9 (sd=18.0) (lingual aspect). The corresponding GB-values were 4.4 (sd=4.8) and 12.5 (sd=10.2). The coefficients of variation of the GBMD index values were consistently lower than those of the GB values. Smoking and tea-drinking were found to be the only significant (p<0.001) factors investigated for stain formation. CONCLUSIONS: It is concluded that the modified index may well be advantageous to its conventional counterpart because sites with most visible stain are assessed separately and because it may also offer higher discriminatory power due to a lower coefficient of variation.

Development of a method in situ to study toothpaste abrasion of dentine. Comparison of 2 products.

BACKGROUND/AIMS: The abrasivity of toothpastes is usually determined using in vitro methods; as such, the clinical significance of the findings is uncertain. The aim of the present study was to develop and evaluate a method in situ to study abrasion of dentine by two toothpastes of different Relative Dentine Abrasivity (RDA). METHOD: The study was a single blind, randomised, 2 way cross over design involving 10 healthy dentate volunteers. Subjects wore an maxillary removable acrylic appliance containing two flat human dentine specimens, taped to expose a window of tissue, from 9 am to 4 pm during the two 10 working day study periods. No food or drink was consumed when the appliance was in place. On five occasions each day, the appliances were removed and the dentine windows brushed ex vivo with the allocated paste for 60 s each. Dentine abrasion at days 5 and 10 was measured using a profilometer. RESULTS: Both toothpastes produced measurable abrasion in all subjects and the depth increased in most subjects between 5 and 10 days. There was significant subject and specimen variation both within and between toothpastes. There was significantly increased abrasion by the toothpaste with the higher RDA value and in mean terms the ratio of abrasion between the two pastes was similar to the ratio of the RDA values. CONCLUSION: The method in situ, already used to study dental hard tissue erosion, appears ideally suitable to study dental abrasion alone and the interaction between aetiological factors involved in tooth wear.

Investigation of erosion and abrasion on enamel and dentine: a model in situ using toothpastes of different abrasivity.

BACKGROUND: Studies in vitro suggest that abrasion and erosion may act synergistically to produce wear of enamel and dentine. Methods in situ are recently available to study separately erosion and abrasion of dental tissues. The aim of this study was to combine two in situ protocols to study the interplay between erosion and abrasion of enamel and dentine. METHOD: The study was a single-blind, randomised, five-treatment cross-over design involving 15 healthy volunteers. During each 10-day study period, subjects wore from 0900 to 1700 h an upper removable acrylic appliance holding one polished enamel and one polished dentine specimen. The specimen treatment regimens were: 1. Drinking water and brushing with toothpaste A. 2. Drinking water and brushing with toothpaste B. 3. Drinking orange juice. 4. Drinking orange juice and brushing with toothpaste A. 5. Drinking orange juice and brushing with toothpaste B. Drinking and brushing times were around 0900, 1100, 1300 and 1500 h. Drinks were consumed as 250 ml over 10 min and brushing ex vivo for 1 min to each specimen. Measurement of tissue loss was made on days 5 and 10 of each period using a profilometer. RESULTS: All treatments produced increasing tissue loss over time, which was considerably greater for dentine than enamel. For enamel, the data at days 5 and 10 showed a significant effect for erosion (i.e. orange juice was significantly more erosive than water), but no significant effect for abrasion (i.e. no significant difference between the two toothpaste treatments). The combined orange juice and toothpaste effects were directional for synergy but did not reach significance. For dentine at day 10, many specimens exceeded the 50 microm set limit of the profilometer and only day 5 data were considered. There were significant effects for erosion (orange juice produced significantly more erosion than water) and for abrasion (paste A was significantly more abrasive to dentine than paste B). The synergy effect could not be examined for dentine due to the truncation effect as the set limit of the profilometer was exceeded. CONCLUSIONS: Erosion increases the susceptibility of enamel to toothpaste abrasion. Dentine is considerably more susceptible than enamel to erosion and abrasion alone or combined. Dentine loss appears to correlate with toothpaste abrasivity (RDA value).