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Ion-temperature-gradient-driven (ITG) turbulence is compared for two quasi-symmetric (QS) stellarator configurations to determine the relationship between linear growth rates and nonlinear heat fluxes. We focus on the quasi-helically symmetric (QHS) stellarator HSX and the quasi-axisymmetric (QAS) stellarator NCSX. In normalized units, HSX exhibits higher growth rates than NCSX, while heat fluxes in gyro-Bohm units are lower in HSX. These results hold for simulations made with both adiabatic and kinetic electrons. The results show that HSX has a larger number of subdominant modes than NCSX and that eigenmodes are more spatially extended in HSX. We conclude that the consideration of nonlinear physics is necessary to accurately assess the heat flux due to ITG turbulence when comparing QS stellarator equilibria.
The Rio Grande Cone is a major fanlike depositional feature in the continental slope of the Pelotas Basin, Southern Brazil. Two representative sediment cores collected in the Cone area were retrieved using a piston core device. In this work, the organic matter (OM) in the sediments was characterized for a continental vs. marine origin using chemical proxies to help constrain the origin of gas in hydrates. The main contribution of OM was from marine organic carbon based on the stable carbon isotope (δ13C-org) and total organic carbon/total nitrogen ratio (TOC:TN) analyses. In addition, the 14C data showed important information about the origin of the OM and we suggest some factors that could modify the original organic matter and therefore mask the “real” 14C ages: (1) biological activity that could modify the carbon isotopic composition of bulk terrestrial organic matter values, (2) the existence of younger sediments from mass wasting deposits unconformably overlying older sediments, and (3) the deep-sediment-sourced methane contribution due to the input of “old” (>50 ka) organic compounds from migrating fluids.
Regional to global high-resolution correlation and timing is critical when attempting to answer important geological questions, such as the greenhouse to icehouse transition that occurred during the Eocene–Oligocene boundary transition. Timing of these events on a global scale can only be answered using correlation among many sections, and multiple correlation proxies, including biostratigraphy, lithostratigraphy, geochemistry and geophysical methods. Here we present litho- and biostratigraphy for five successions located in the southeastern USA. To broaden the scope of correlation, we also employ carbon and oxygen stable isotope and magnetic susceptibility (χ) data to interpret these sections regionally, and correlate to the Global Boundary Stratotype Section and Point (GSSP) near Massignano in central Italy. Our results indicate that approaching the Eocene–Oligocene boundary, climate warmed slightly, but then δ18O data exhibit an abrupt c. +5 ‰ positive shift towards cooling that reached a maximum c. 1 m below the boundary at St Stephens Quarry, Alabama. This shift was accompanied by a c. −3 ‰ negative shift in δ13C interpreted to indicate environmental changes associated with the onset of the Eocene–Oligocene boundary planktonic foraminiferal extinction event. The observed cold pulse may be responsible for the final extinction of Hantkeninidae, used to define the beginning of the Rupelian Stage. Immediately preceding the boundary, Hantkeninidae species dropped significantly in abundance and size (pre-extinction dwarfing occurring before the final Eocene–Oligocene extinctions), and these changes may be the reason for inconsistencies in past Eocene–Oligocene boundary placement in the southeastern USA.
To assess the effect of topical betahistine on Eustachian tube function in subjectively abnormal subjects in a hyperbaric chamber.
Active and passive Eustachian tube function was examined using tympanometry in a pressure chamber.
Active Eustachian tube function was tested against the negative middle ear pressure induced by increasing the chamber pressure to +3 kPa. One voluntary swallow decreased middle-ear pressure by a mean of 1.36 kPa. Passive Eustachian tube function was tested by measuring spontaneous Eustachian tube openings as the chamber pressure dropped from +10 kPa to ambient. Four distinct patterns of Eustachian tube behaviour were seen, three of which indicated Eustachian tube dysfunction. Betahistine had no positive effect on Eustachian tube opening, although previous animal studies had suggested a beneficial effect.
Topical betahistine had no effect on Eustachian tube function. Combining a hyperbaric chamber with tympanometry proved ideal for evaluating Eustachian tube function.
Objective: Concussion in children and adolescents is a prevalent problem with implications for subsequent physical, cognitive, behavioral, and psychological functioning, as well as quality of life. While these consequences warrant attention, most concussed children recover well. This study aimed to determine what pre-injury, demographic, and injury-related factors are associated with optimal outcome (“wellness”) after pediatric concussion. Method: A total of 311 children 6–18 years of age with concussion participated in a longitudinal, prospective cohort study. Pre-morbid conditions and acute injury variables, including post-concussive symptoms (PCS) and cognitive screening (Standardized Assessment of Concussion, SAC), were collected in the emergency department, and a neuropsychological assessment was performed at 4 and 12 weeks post-injury. Wellness, defined by the absence of PCS and cognitive inefficiency and the presence of good quality of life, was the main outcome. Stepwise logistic regression was performed using 19 predictor variables. Results: 41.5% and 52.2% of participants were classified as being well at 4 and 12 weeks post-injury, respectively. The final model indicated that children who were younger, who sustained sports/recreational injuries (vs. other types), who did not have a history of developmental problems, and who had better acute working memory (SAC concentration score) were significantly more likely to be well. Conclusions: Determining the variables associated with wellness after pediatric concussion has the potential to clarify which children are likely to show optimal recovery. Future work focusing on wellness and concussion should include appropriate control groups and document more extensively pre-injury and injury-related factors that could additionally contribute to wellness. (JINS, 2019, 25, 375–389)
To ascertain opinions regarding etiology and preventability of hospital-onset bacteremia and fungemia (HOB) and perspectives on HOB as a potential outcome measure reflecting quality of infection prevention and hospital care.
Hospital epidemiologists and infection preventionist members of the Society for Healthcare Epidemiology of America (SHEA) Research Network.
A web-based, multiple-choice survey was administered via the SHEA Research Network to 133 hospitals.
A total of 89 surveys were completed (67% response rate). Overall, 60% of respondents defined HOB as a positive blood culture on or after hospital day 3. Central line-associated bloodstream infections and intra-abdominal infections were perceived as the most frequent etiologies. Moreover, 61% thought that most HOB events are preventable, and 54% viewed HOB as a measure reflecting a hospital’s quality of care. Also, 29% of respondents’ hospitals already collect HOB data for internal purposes. Given a choice to publicly report central-line–associated bloodstream infections (CLABSIs) and/or HOB, 57% favored reporting either HOB alone (22%) or in addition to CLABSI (35%) and 34% favored CLABSI alone.
Among the majority of SHEA Research Network respondents, HOB is perceived as preventable, reflective of quality of care, and potentially acceptable as a publicly reported quality metric. Further studies on HOB are needed, including validation as a quality measure, assessment of risk adjustment, and formation of evidence-based bundles and toolkits to facilitate measurement and improvement of HOB rates.
Correction factors, termed α-factors, similar to those defined by LaChance and Traill have been generated by the addition of variable, known amounts of individual oxides, or other compounds, to a base cement sample and measuring the x-ray intensities of the elements of interest. The effects of all common constituents of cement on the determination of CaO, SiO2 and Al2O3 were found. Factors for rhodium and chromium primary radiation were determined and, in general, showed small but significant differences. The factors for rhodium at 50kV and 30kV were substantia11y identical. The correction factors were tested through the use of the NBS 1011- 1016 cements as reference standards to analyze the new proposed NBS cement series. The correction factors not only furnished improved calibration curves, but also allowed the determination of CaO, Al2O3 and SiO2 with an average deviation of less than 0.2% (absolute) from the provisional values furnished with the standard samples.
We evaluated whether a diagnostic stewardship initiative consisting of ASP preauthorization paired with education could reduce false-positive hospital-onset (HO) Clostridioides difficile infection (CDI).
Single center, quasi-experimental study.
Tertiary academic medical center in Chicago, Illinois.
Adult inpatients were included in the intervention if they were admitted between October 1, 2016, and April 30, 2018, and were eligible for C. difficile preauthorization review. Patients admitted to the stem cell transplant (SCT) unit were not included in the intervention and were therefore considered a contemporaneous noninterventional control group.
The intervention consisted of requiring prescriber attestation that diarrhea has met CDI clinical criteria, ASP preauthorization, and verbal clinician feedback. Data were compared 33 months before and 19 months after implementation. Facility-wide HO-CDI incidence rates (IR) per 10,000 patient days (PD) and standardized infection ratios (SIR) were extracted from hospital infection prevention reports.
During the entire 52 month period, the mean facility-wide HO-CDI-IR was 7.8 per 10,000 PD and the SIR was 0.9 overall. The mean ± SD HO-CDI-IR (8.5 ± 2.0 vs 6.5 ± 2.3; P < .001) and SIR (0.97 ± 0.23 vs 0.78 ± 0.26; P = .015) decreased from baseline during the intervention. Segmented regression models identified significant decreases in HO-CDI-IR (Pstep = .06; Ptrend = .008) and SIR (Pstep = .1; Ptrend = .017) trends concurrent with decreases in oral vancomycin (Pstep < .001; Ptrend < .001). HO-CDI-IR within a noninterventional control unit did not change (Pstep = .125; Ptrend = .115).
A multidisciplinary, multifaceted intervention leveraging clinician education and feedback reduced the HO-CDI-IR and the SIR in select populations. Institutions may consider interventions like ours to reduce false-positive C. difficile NAAT tests.
Tardive dyskinesia (TD) is an often-irreversible movement disorder that may intensify the stigma of patients with psychiatric disorders and worsen quality of life. In two randomized, double-blind, placebo (PBO)-controlled, 12-week trials, ARM-TD and AIM-TD (‘parent studies’), deutetrabenazine (DTB) demonstrated statistically significant improvements in centrally read Abnormal Involuntary Movement Scale (AIMS) scores at Week 12 compared with PBO and was generally well tolerated.
To evaluate the long-term efficacy of DTB in an open-label safety study following double-blind treatment using site-rated efficacy measures: AIMS, the Clinical Global Impression of Change (CGIC) and the Patient Global Impression of Change (PGIC), which may be used in real-world clinical practice settings.
Patients with TD who completed the parent studies were eligible to enter this open-label, long-term extension (OLE) after completing the 1-week washout period and final evaluation in the blinded portion of the trial. This extension comprised a 6-week titration period followed by a long-term maintenance phase. Patients began DTB at 12mg/day, titrating up to a maximum total dose of 48mg/day based on dyskinesia control and tolerability. Efficacy endpoints included in this analysis are the change in site-rated AIMS score (items 1–7) from parent study baseline, and the proportion of patients who were “Much Improved” or “Very Much Improved” (treatment success) on the CGIC and PGIC from OLE baseline.
At the end of the parent studies (Week 12), patients treated with DTB had experienced greater mean (standard error) improvements in site-rated AIMS score (–5.0[0.40]) than patients given PBO (–3.2[0.47]). With long-term DTB treatment, both groups experienced improvements in site-rated AIMS scores (prior DTB, –7.9[0.62]; prior placebo, –6.6[0.64]) compared with parent study baseline. Similarly, at the end of the parent studies, a greater proportion of patients treated with DTB had treatment success on the CGIC (DTB, 51%; PBO, 32%) and the PGIC (DTB, 46%; PBO: 33%); whereas at Week 54 of the OLE study, treatment success on CGIC and PGIC were similar in both the CGIC (prior DTB: 66%; prior PBO: 68%) and PGIC (prior DTB: 62%; prior PBO: 62%) groups. DTB was generally well tolerated.
Patients treated with DTB showed improvements in abnormal movements, as measured by site-rated AIMS, CGIC, and PGIC scores, which may be used in real-world clinical practice settings. These results corroborate the previously reported efficacy of DTB as observed in the 12-week, double-blind ARM-TD and AIM-TD trials, in which central raters were used to evaluate AIMS scores.
Presented at: American Psychiatric Association Annual Meeting; May 5–9, 2018, New York, New York, USA
Funding Acknowledgements: Funding: This study was supported by Teva Pharmaceuticals, Petach Tikva, Israel.
To evaluate the long-term safety and tolerability of deutetrabenazine in patients with tardive dyskinesia (TD) at 2years.
In the 12-week ARM-TD and AIM-TD studies, deutetrabenazine showed clinically significant improvements in Abnormal Involuntary Movement Scale scores compared with placebo, and there were low rates of overall adverse events (AEs) and discontinuations associated with deutetrabenazine.
Patients who completed ARM-TD or AIM-TD were included in this open-label, single-arm extension study, in which all patients restarted/started deutetrabenazine 12mg/day, titrating up to a maximum total daily dose of 48mg/day based on dyskinesia control and tolerability. The study comprised a 6-week titration period and a long-term maintenance phase. Safety measures included incidence of AEs, serious AEs (SAEs), and AEs leading to withdrawal, dose reduction, or dose suspension. Exposure-adjusted incidence rates (EAIRs; incidence/patient-years) were used to compare AE frequencies for long-term treatment with those for short-term treatment (ARM-TD and AIM-TD). This analysis reports results up to 2 years (Week106).
343 patients were enrolled (111 patients received placebo in the parent study and 232 received deutetrabenazine). There were 331.4 patient-years of exposure in this analysis. Through Week 106, EAIRs of AEs were comparable to or lower than those observed with short-term deutetrabenazine and placebo, including AEs of interest (akathisia/restlessness [long-term EAIR: 0.02; short-term EAIR range: 0–0.25], anxiety [0.09; 0.13–0.21], depression [0.09; 0.04–0.13], diarrhea [0.06; 0.06–0.34], parkinsonism [0.01; 0–0.08], somnolence/sedation [0.09; 0.06–0.81], and suicidality [0.02; 0–0.13]). The frequency of SAEs (EAIR 0.15) was similar to those observed with short-term placebo (0.33) and deutetrabenazine (range 0.06–0.33) treatment. AEs leading to withdrawal (0.08), dose reduction (0.17), and dose suspension (0.06) were uncommon.
These results confirm the safety outcomes seen in the ARM-TD and AIM-TD parent studies, demonstrating that deutetrabenazine is well tolerated for long-term use in TD patients.
Presented at: American Academy of Neurology Annual Meeting; April 21–27, 2018, Los Angeles, California,USA
Funding Acknowledgements: Funding: This study was supported by Teva Pharmaceuticals, Petach Tikva, Israel
Tardive dyskinesia (TD) results from exposure to dopamine-receptor antagonists (DRAs), such as typical and atypical antipsychotics. Clinicians commonly manage TD by reducing the dose of or stopping the causative agent; however, this may cause psychiatric relapse and worsen quality of life. In the 12-week ARM-TD and AIM-TD trials, deutetrabenazine demonstrated statistically significant improvements in Abnormal Involuntary Movement Scale (AIMS) scores versus placebo and was generally well tolerated, regardless of baseline DRA use or comorbidities.
To evaluate the impact of underlying disease and current DRA use on efficacy and safety of long-term therapy of deutetrabenazine in patients with TD.
Patients with TD who completed ARM-TD or AIM-TD were eligible to enter this open-label, single-arm, long-term extension after completing the 1-week washout period and final evaluation in the blinded portion of the trial. Change in AIMS scores from baseline to Week 54 and patients “Much Improved” or “Very Much Improved” (treatment success) on the Clinical Global Impression of Change (CGIC) and Patient Global Impression of Change (PGIC) at Week 54 were analyzed by baseline psychiatric illness type, including mood disorders (bipolar disorder/depression/other) or psychotic disorders (schizophrenia/schizoaffective disorder), and presence or absence of current DRA use.
At Week 54, meaningful improvements from baseline in mean (standard error) AIMS scores were observed for patients with baseline mood disorders (–5.2[0.93]) and psychotic disorders (–5.0[0.63]), and in patients currently using DRAs (–4.6[0.54]) or not using DRAs (–6.4[1.27]). Most patients with mood disorders (73%) and psychotic disorders (71%) were “Much Improved” or “Very Much Improved” on CGIC at Week 54, similar to patients currently using (71%) or not using (74%) DRAs. The majority of patients with mood disorders (62%) and psychotic disorders (57%), as well as patients currently using (58%) or not using (63%) DRAs, were also “Much Improved” or “Very Much Improved” on PGIC at Week 54. Prior treatment in ARM-TD and AIM-TD did not impact the long-term treatment response. Underlying psychiatric disorder and concomitant DRA use did not impact the occurrence of adverse events (AEs). The frequencies of dose reductions, dose suspensions, and withdrawals due to AEs were low, regardless of baseline psychiatric comorbidities and DRAuse.
Long-term deutetrabenazine treatment demonstrated meaningful improvements in abnormal movements in TD patients, which were recognized by clinicians and patients, regardless of underlying psychiatric illness or DRAuse.
Presented at: American Psychiatric Association Annual Meeting; May 5–9, 2018, New York, New York, USA
Funding Acknowledgements: This study was supported by Teva Pharmaceuticals, Petach Tikva, Israel.
To evaluate long-term efficacy of deutetrabenazine in patients with tardive dyskinesia (TD) by examining response rates from baseline in Abnormal Involuntary Movement Scale (AIMS) scores. Preliminary results of the responder analysis are reported in this analysis.
In the 12-week ARM-TD and AIM-TD studies, the odds of response to deutetrabenazine treatment were higher than the odds of response to placebo at all response levels, and there were low rates of overall adverse events and discontinuations associated with deutetrabenazine.
Patients with TD who completed ARM-TD or AIM-TD were included in this open-label, single-arm extension study, in which all patients restarted/started deutetrabenazine 12mg/day, titrating up to a maximum total daily dose of 48mg/day based on dyskinesia control and tolerability. The study comprised a 6-week titration and a long-term maintenance phase. The cumulative proportion of AIMS responders from baseline was assessed. Response was defined as a percent improvement from baseline for each patient from 10% to 90% in 10% increments. AlMS score was assessed by local site ratings for this analysis.
343 patients enrolled in the extension study (111 patients received placebo in the parent study and 232 patients received deutetrabenazine). At Week 54 (n=145; total daily dose [mean±standard error]: 38.1±0.9mg), 63% of patients receiving deutetrabenazine achieved ≥30% response, 48% of patients achieved ≥50% response, and 26% achieved ≥70% response. At Week 80 (n=66; total daily dose: 38.6±1.1mg), 76% of patients achieved ≥30% response, 59% of patients achieved ≥50% response, and 36% achieved ≥70% response. Treatment was generally well tolerated.
Patients who received long-term treatment with deutetrabenazine achieved response rates higher than those observed in positive short-term studies, indicating clinically meaningful long-term treatment benefit.
Presented at: American Academy of Neurology Annual Meeting; April 21–27, 2018, Los Angeles, California, USA.
Funding Acknowledgements: This study was supported by Teva Pharmaceuticals, Petach Tikva, Israel.
Background: Mindfulness-based cognitive therapy (MBCT) has evidence of efficacy in a range of populations, but few studies to date have reported on MBCT for treatment of anxious and depressive symptoms in Parkinson's disease (PD). Aims: The aim of this study was to examine the efficacy of modified MBCT in reducing symptoms of anxiety and depression and improving quality of life in PD. Method: Thirty-six individuals with PD were randomly assigned to either modified MBCT or a waitlist control. Changes in symptoms of anxiety, depression and quality of life were compared at group level using generalized linear mixed models and at individual level using reliable change analysis. Results: At post-treatment, there was a significant reduction in depressive symptoms for people undertaking modified MBCT at both group and individual levels compared with controls. There was no significant effect on anxiety or quality of life at the group level, although significantly more people had reliable improvement in anxiety after modified MBCT than after waitlist. Significantly more waitlist participants had reliable deterioration in symptoms of anxiety and depression than those completing modified MBCT. Most participants stayed engaged in modified MBCT, with only three drop-outs. Discussion: This proof-of-concept study demonstrates the potential efficacy of modified MBCT as a treatment for depressive symptoms in Parkinson's disease and suggests further research is warranted.
Bipolar disorder (BD) is associated with attentional and processing abnormalities. Such abnormalities are also seen in healthy subjects with sleep disruption. We hypothesised cognitive abnormalities in BD patients would be worse in those with objectively verified sleep abnormalities.
Forty-six BD patients and 42 controls had comprehensive sleep/circadian rhythm assessment over 21 days alongside mood questionnaires. Cognitive function was assessed with a range of tasks including Psychomotor Vigilance Test (PVT), Attention Network Task (ANT) and Digit Symbol Substitution Test (DSST). BD participants with normal and abnormal sleep were compared with age- and sex-matched controls.
BD patients had longer response times and made more lapses (responses >500 ms) than controls on the PVT (both p < 0.001). However, patients with normal sleep patterns did not differ from controls while those with sleep abnormalities did (p < 0.001). An identical pattern of effects were seen with the ANT response times, with the abnormality in bipolar abnormal sleepers related to the executive attentional network. Similarly, patients made fewer correct responses on the DSST compared with the controls (p < 0.001). Bipolar normal sleepers did not differ while those with abnormal sleep did (p < 0.001). All these differences were seen in bipolar abnormal sleepers who were euthymic (p < 0.01) and across the main abnormal sleep phenotypes.
We confirm impairment in attention and processing speed in BD. Rather than sleep abnormalities exacerbating such dysfunction, the impairments were confined to bipolar abnormal sleepers, consistent with sleep disturbance being the main driver of cognitive dysfunction.
Childhood maltreatment is one of the strongest predictors of adulthood depression and alterations to circulating levels of inflammatory markers is one putative mechanism mediating risk or resilience.
To determine the effects of childhood maltreatment on circulating levels of 41 inflammatory markers in healthy individuals and those with a major depressive disorder (MDD) diagnosis.
We investigated the association of childhood maltreatment with levels of 41 inflammatory markers in two groups, 164 patients with MDD and 301 controls, using multiplex electrochemiluminescence methods applied to blood serum.
Childhood maltreatment was not associated with altered inflammatory markers in either group after multiple testing correction. Body mass index (BMI) exerted strong effects on interleukin-6 and C-reactive protein levels in those with MDD.
Childhood maltreatment did not exert effects on inflammatory marker levels in either the participants with MDD or the control group in our study. Our results instead highlight the more pertinent influence of BMI.
Declaration of interest
D.A.C. and H.W. work for Eli Lilly Inc. R.N. has received speaker fees from Sunovion, Jansen and Lundbeck. G.B. has received consultancy fees and funding from Eli Lilly. R.H.M.-W. has received consultancy fees or has a financial relationship with AstraZeneca, Bristol-Myers Squibb, Cyberonics, Eli Lilly, Ferrer, Janssen-Cilag, Lundbeck, MyTomorrows, Otsuka, Pfizer, Pulse, Roche, Servier, SPIMACO and Sunovian. I.M.A. has received consultancy fees or has a financial relationship with Alkermes, Lundbeck, Lundbeck/Otsuka, and Servier. S.W. has sat on an advisory board for Sunovion, Allergan and has received speaker fees from Astra Zeneca. A.H.Y. has received honoraria for speaking from Astra Zeneca, Lundbeck, Eli Lilly, Sunovion; honoraria for consulting from Allergan, Livanova and Lundbeck, Sunovion, Janssen; and research grant support from Janssen. A.J.C. has received honoraria for speaking from Astra Zeneca, honoraria for consulting with Allergan, Livanova and Lundbeck and research grant support from Lundbeck.
In this study, we sought to evaluate the influence of cigarette smoke and pH cycling on the chemical composition and surface/cross-sectional enamel microhardness. A total of 40 dental blocks obtained from bovine incisors were divided into four groups (n=10): no treatment (control); exposure to cigarette smoke (CS); exposure to pH cycling (PC); and exposure to cigarette smoke and pH cycling (CS-PC). The samples were analyzed by synchrotron radiation micro X-ray fluorescence, bench mode X-ray fluorescence, as well as surface microhardness (SMH) and cross-sectional microhardness (CSMH) testing. The SMH results were submitted to analysis of variance (ANOVA) and Tukey’s test. The CSMH results were evaluated using split-plot ANOVA and Tukey’s test. A high amount of Cd and Pb and traces of Ni and As were observed in enamel and dentin after exposure to cigarette smoke (CS and CS-PC). The SMH and CSMH of CS were statistically higher when compared with the control. The PC and CS-PC showed lower SMH and CSMH. We conclude that exposure to cigarette smoke promoted heavy metal deposition in enamel/dentin. In addition, it increased the enamel microhardness but did not promote a protective effect on the in vitro development of caries. The clinical significance of this work is that there is significant bioaccumulation of heavy metals from cigarette smoke on the surface and in the enamel and dentin.