Electronic cigarettes: an update on products, regulation, public health approaches and oral health.

BACKGROUND: Electronic cigarettes remain a divisive topic amongst public health experts and researchers. The division hinges on the the role of e-cigarettes in public health, i.e., whether e-cigarettes represent a potential to compromise decades of public health efforts by driving smoking rates up, or an effective tool to drive smoking rates down. Dental settings are a strategic place for stop smoking interventions, with large proportions of the population attending regularly and harms of smoking often presenting early in the mouth. Dental professionals should be equipped with the necessary information to provide evidence-based advice and recommendations to their patients. OBJECTIVE: To update dental professionals and researchers on the current regulations, public health approaches, and oral health effects of prevailing novel nicotine products, with a focus on e-cigarettes. METHODS: Narrative literature review. PRINCIPLE FINDINGS: Regulatory approaches vary considerably around the world but in the UK and Europe, e-cigarettes are regulated as consumer or medicinal product, and their use is permitted. In the UK, e-cigarettes have increasingly been supported by public health institutions for smoking cessation as part of a Tobacco Harm Reduction strategy. The potential harms (including to oral health) from e-cigarette use are likely to be much less than from tobacco cigarettes.

Tobacco education in UK dental schools: A survey of current practice.

OBJECTIVE: To investigate the current provision of tobacco education (tobacco use and cessation), assessment and e-cigarette education in UK dental and dental hygiene and therapy (DHT) undergraduate programmes. MATERIALS AND METHODS: The study was conducted using a self-administered questionnaire sent to all UK institutions training dental and DHT students during the academic year 2015/2016. RESULTS: Twenty-five programmes returned completed questionnaires (response rate 68%). All programmes (100%) reported delivering tobacco education, delivered by multiple individuals in 78% of the programmes. Assessment of the theoretical and practical aspects of tobacco education was reported in 80% and 72% of the programmes, respectively. More formal teaching time was devoted to the theoretical aspects (100% >2 hours) rather than the practical aspects (76% > 2 hours) of tobacco education. All programmes expected their graduates to be clinically competent at discussing the health consequences of smoking, deliver a brief smoking cessation intervention, and referring patients to stop smoking services. The use of the National Centre for Smoking Cessation and Training "Very Brief Advice" (NCSCT VBA) training package was reported to be mandatory in 36%, and recommended, in 44% of programmes. Specialised stop smoking services delivered teaching in 40% of both dental and DHT training programmes whilst another 40% reported previous input from specialist smoking cessation services but not in 2015/2016. Most programmes reported delivery of teaching on electronic cigarettes, with 12% delivering a standalone lecture on this topic. CONCLUSIONS: Tobacco education is an important component of dental training. Dental education programmes should remain responsive to a rapidly changing field and fully utilise the available resources.

Outcomes of non-surgical periodontal treatment by dental hygienists in training: impact of site- and patient-level factors.

OBJECTIVES: To investigate the site- and patient-level factors that impact on the response to non-surgical periodontal therapy in patients with chronic periodontitis. METHODS: A retrospective evaluation of clinical outcomes following non-surgical periodontal therapy delivered by dental hygienists in training was undertaken. Case notes from 195 patients with chronic periodontitis were reviewed and clinical data pre- and post-treatment abstracted. Patients were categorized as 'responders' or 'non-responders' according to defined outcome criteria, and the relationship between clinical and demographic variables and treatment outcomes was assessed. RESULTS: Overall, there was a good response to the periodontal treatment. At deep sites (those with pretreatment probing depth ≥5 mm), the mean probing depth reduction was 1.6 ± 0.9 mm. Seventy-one (36%) patients were classified as non-responders (indicating that at least 30% of their deep sites did not improve by at least 2 mm following treatment). The non-responding group contained a significantly greater proportion of smokers (28%) than the responding group (16%). Plaque scores did not differ significantly between responders or non-responders either pre- or post-treatment. Regression analyses indicated that smoking status (odds ratio, OR: 2.04), mean pretreatment probing depth (OR: 1.49) and percentage of deep sites ≥5 mm at pretreatment (OR: 1.02) were significantly associated with response to treatment. CONCLUSION: This study supports the benefits of non-surgical therapy in the treatment of chronic periodontitis by dental hygienists in training. Better responses to treatment tend to be observed in non-smokers and in those with less advanced periodontitis at baseline.

Waterline Disinfectants Reduce Dental Bioaerosols: A Multitracer Validation.

Oral microbes are dispersed during dental treatment and reduction methods have been proposed, but dental unit waterline (DUWL) disinfectants have received little attention; specifically, the effect on viruses has not been studied. This study aims to 1) investigate the effect of DUWL disinfectants on viral dispersion in dental bioaerosols and 2) establish a dual-tracer system using live bacteriophage and fluorescein supported by optical particle measurement. Bacteriophage MS2 was used as a viral tracer and fluorescein as a fluorescent tracer. Validation experiments were conducted to exclude interference of one tracer with the other or of DUWL disinfectants on detection methods. Simulated "saliva" containing the tracers was infused into the mouth of a dental mannequin during 10-min dental procedures with an air turbine handpiece (n = 3 replicates). Aerosols and droplets were sampled in an enclosed dental operatory using air samplers and settlement onto sterile filter papers. Bacteriophage was quantified using plaque assays and reverse transcription quantitative polymerase chain reaction (RT-qPCR). Fluorescein was quantified fluorometrically. The effect of DUWL disinfectants on total aerosol concentration was assessed in separate experiments using an optical particle counter. DUWL disinfectants reduced bacteriophage viability, and interference between tracers was not observed. In simulated clinical procedures, the disinfectant ICX reduced bacteriophage detection substantially (P < 0.001; 2-way analysis of variance). MS2 RNA was detected in all experimental samples but not negative controls. Samples positive on RT-qPCR but not plaque assays may indicate that virions at distant sites are nonviable. Fluorescein tracer showed good agreement with the bacteriophage tracer. DUWL disinfectants designed for continuous presence in irrigants reduce the dispersion of viable virus in dental bioaerosols during simulated procedures. Their use may therefore be important for routine infection control and as a mitigation factor during infectious disease outbreaks. Future studies should explore this using a range of viruses and other microbes.

Local Exhaust Ventilation to Control Dental Aerosols and Droplets.

Dental procedures produce aerosols that may remain suspended and travel significant distances from the source. Dental aerosols and droplets contain oral microbes, and there is potential for infectious disease transmission and major disruption to dental services during infectious disease outbreaks. One method to control hazardous aerosols often used in industry is local exhaust ventilation (LEV). The aim of this study was to investigate the effect of LEV on aerosols and droplets produced during dental procedures. Experiments were conducted on dental mannequins in an 825.4-m3 open-plan clinic and a 49.3-m3 single surgery. Ten-minute crown preparations were performed with an air-turbine handpiece in the open-plan clinic and 10-min full-mouth ultrasonic scaling in the single surgery. Fluorescein was added to instrument irrigation reservoirs as a tracer. In both settings, optical particle counters (OPCs) were used to measure aerosol particles between 0.3 and 10.0 µm, and liquid cyclone air samplers were used to capture aerosolized fluorescein tracer. In addition, in the open-plan setting, fluorescein tracer was captured by passive settling onto filter papers in the environment. Tracer was quantified fluorometrically. An LEV device with high-efficiency particulate air filtration and a flow rate of 5,000 L/min was used. LEV reduced aerosol production from the air-turbine handpiece by 90% within 0.5 m, and this was 99% for the ultrasonic scaler. OPC particle counts were substantially reduced for both procedures and air-turbine settled droplet detection reduced by 95% within 0.5 m. The effect of LEV was substantially greater than suction alone for the air-turbine and was similar to the effect of suction for the ultrasonic scaler. LEV reduces aerosol and droplet contamination from dental procedures by at least 90% in the breathing zone of the operator, and it is therefore a valuable tool to reduce the dispersion of dental aerosols.

Electronic Cigarettes and Oral Health.

Novel nicotine products, particularly electronic cigarettes (e-cigarettes), have become increasingly popular over the past decade. E-cigarettes are sometimes regarded as a less harmful alternative to tobacco smoking, and there is some evidence of their potential role as a smoking cessation aid. However, there are concerns about their health consequences, particularly in users who are not tobacco smokers, and also when used long term. Given the mode of delivery of these products, there is potential for oral health consequences. Over the past few years, there have been an increasing number of studies conducted to explore their oral health effects. In vitro studies have reported a range of cellular effects, but these are much less pronounced than those resulting from exposure to tobacco smoke. Microbiological studies have indicated that e-cigarette users have a distinct microbiome, and there is some indication this may be more pathogenic compared to nonusers. Evidence of oral health effects from clinical trials is still limited, and most studies to date have been small in scale and usually cross-sectional in design. Epidemiological studies highlight concerns over oral dryness, irritation, and gingival diseases. Interpreting data from e-cigarette studies is challenging, given the different populations that have been investigated and the continual emergence of new products. Overall, studies reveal potential oral health harms, underscoring the importance of efforts to reduce use in nonsmokers. However, in smokers who are using e-cigarettes as an aid to help them quit, the benefits of quitting tobacco smoking may outweigh any negative oral health impacts of e-cigarette use, particularly in the short term. Future research is needed to understand the clinical significance of some of the biological changes observed by following different cohorts of users longitudinally in carefully designed clinical studies and pragmatic trials supported by high-quality in vitro studies.

Developmental reversals in false memory: Effects of emotional valence and arousal.

Do the emotional valence and arousal of events distort children's memories? Do valence and arousal modulate counterintuitive age increases in false memory? We investigated those questions in children, adolescents, and adults using the Cornell/Cortland Emotion Lists, a word list pool that induces false memories and in which valence and arousal can be manipulated factorially. False memories increased with age for unpresented semantic associates of word lists, and net accuracy (the ratio of true memory to total memory) decreased with age. These surprising developmental trends were more pronounced for negatively valenced materials than for positively valenced materials, they were more pronounced for high-arousal materials than for low-arousal materials, and developmental increases in the effects of arousal were small in comparison with developmental increases in the effects of valence. These findings have ramifications for legal applications of false memory research; materials that share the emotional hallmark of crimes (events that are negatively valenced and arousing) produced the largest age increases in false memory and the largest age declines in net accuracy.

The inheritance of epigenetic defects.

Evidence from many sources shows that the control of gene expression in higher organisms is related to the methylation of cytosine in DNA, and that the pattern of methylation is inherited. Loss of methylation, which can result from DNA damage, will lead to heritable abnormalities in gene expression, and these may be important in oncogenesis and aging. Transformed permanent lines often lose gene activity through de novo methylation. It is proposed that epigenetic defects in germline cells due to loss of methylation can be repaired by recombination at meiosis but that some are transmitted to offspring.

Cellular aging: further evidence for the commitment theory.

A large, transient reduction in the population size of human fibroblasts in early passages significantly increases the variability of the life-spans of cultures in comparison to control cultures, as predicted by the commitment theory of cellular aging. The theory also predicts that a constant population of noncycling cells will appear in the later part of the culture life-span. This was confirmed by labeling the cells in culture with tritiated thymidine.

Testing the commitment theory of cellular aging.

The commitment theory may explain both the finite lifespan of diploid fibroblasts and the apparent immortality of transformed lines. Potentially immortal cells are assumed on division to generate with some fixed probability cells committed to senesce after a specific number of divisions. During the period between commitment and senescence, cells are assumed to maintain normal growth so that the uncommitted cells are diluted by committed ones and may ultimately be lost in subculturing. A number of predictions of this model are described and experiments strongly supporting the theory are reported. We conclude that the limited growth of diploid fibroblasts is, in effect, an artifact of normal culturing procedures.

Screening for abdominal aortic aneurysm in asymptomatic at-risk patients using emergency ultrasound.

OBJECTIVE: Abdominal aortic aneurysm (AAA) is a deadly but often clinically silent disease. Patients at increased risk are elderly men with risk factors for vascular disease who may not have adequate screening through primary care. We sought to examine the prevalence and feasibility of screening for AAA in at-risk patients presenting for unrelated complaints using emergency physician-performed bedside ultrasound. METHODS: At-risk patients presenting with unrelated complaints were screened for AAA by emergency physician-performed ultrasound. Scan was rated as complete, limited, or inadequate, and time to complete scan noted. Patients with identified AAA were provided with appropriate follow-up and were followed to look at confirmatory imaging and clinical course. RESULTS: A total of 179 patients were screened, with 12 AAAs discovered (6.7%; 95% confidence interval, 3.9%-11.4%). Average time to perform the screening ultrasound was 141 +/- 135 seconds. Average discrepancy between emergency ultrasound and formal imaging was 3.9 mm. Of 12 (92%) patients, 11 were followed up, with repair recommended in 3 patients. CONCLUSION: The emergency department represents a potential opportunity for screening at-risk patients for AAA. Emergency ultrasound is a fast and accurate method for identifying patients with AAA who may benefit from follow-up or intervention.

Developmental reversals in false memory: Development is complementary, not compensatory.

We report the 1st example of a true complementarity effect in memory development-a situation in which memory for the same event simultaneously becomes more and less accurate between early childhood and adulthood. We investigated this paradoxical effect because fuzzy-trace theory predicts that it can occur in paradigms that produce developmental reversals in false memory, which are circumstances in which adults are more likely than children to remember new events as old. The complementarity prediction is this: If subjects separately judge whether those same events are new but similar to old ones, adults will be more accurate than children, even though adults are less accurate when they judge whether the items are old. We report 4 experiments in which children (6- and 10-year-olds), adolescents (14-year-olds), and adults encoded the modal developmental reversal materials: Deese-Roediger-McDermott lists. Then, they responded to memory tests on which half the subjects judged whether test items were old and half judged whether the same items were new-similar. The paradoxical complementarity effect was detected in all experiments: The tendency to falsely remember new-similar items as being old increased with development, but so did the tendency to correctly remember them as being new-similar. (PsycINFO Database Record

Dental professionals' opinions and knowledge of smoking cessation and electronic cigarettes: a cross-sectional survey in the north of England.

Aims: To determine the current level of knowledge and opinions of UK dental professionals with regards to smoking cessation and e-cigarettes. Method: A self-administered online survey was distributed by postal invitation to all dental practices in the north of England registered on the National Health Service (NHS) Choices website. Findings: One hundred and ninety completed questionnaires were received. Seventy-nine percent of respondents reported always enquiring about the smoking status of their patients with 17% completing referrals to a specialist stop smoking service. Just under half of respondents reported not receiving any smoking cessation advice training. Lack of time during appointments, lack of training and lack of perceived interest by patients were reported as the most important barriers. The importance of a lack of remuneration, as a barrier, varied considerably with professional role. Approximately a third (31%) of respondents were of the opinion that e-cigarettes are more or equally harmful than cigarettes with the majority not aware of any guidance documents or recommendations regarding e-cigarettes. Conclusion: The majority of dental professionals in the north of England reported providing smoking cessation advice, although only half had training on this. Opinions on electronic cigarettes were mixed, with a third having negative views.

Chromosome error propagation and cancer.

A general characteristic of tumour cells is their unstable karyotype. It is suggested here that maintenance of the normal diploid cell depends on the presence of two copies of specific genes; a change in gene dosage of one or more of these genes, by chromosome nondisjunction or rearrangement, may trigger a general loss of accuracy in chromosome segregation at mitosis.

Dual inheritance.

Genetic inheritance in higher organisms normally refers to the transmission of information from one generation to the next. Nevertheless, there is also inheritance in somatic cells, characterised by the phenotypic stability of differentiated cells that divide (such as fibroblasts and lymphocytes), and also mitosis of stem line cells, which gives rise to another stem line daughter cell, and one that will differentiate. Thus, there is a dual inheritance systems in these organisms, one of which is genetic and the other epigenetic. In the latter, heritable information is superimposed on DNA sequences, and one well-known mechanism is heritable methylation of cytosine. Much information will come from the human epigenome project that will reveal the patterns of DNA methylation in distinct differentiated cells. There have also been innumerable studies on the abnormal de novo methylation and silencing of tumour suppressor genes in cancer cells.

Bilateral orbital lymphangiomas in two patients with generalized lymphangiomatosis.

SUMMARY: Generalized lymphangiomatosis is a rare congenital malformation of the lymphatics, characterized by cystic lesions in parenchymal organs and lytic bone lesions. In this report, we describe the radiographic and clinical features of 2 unusual cases of generalized lymphangiomatosis with bilateral orbital involvement.

Azacytidine-induced reactivation of a DNA repair gene in Chinese hamster ovary cells.

Six X-ray-sensitive (xrs) strains of the CHO-K1 cell line were shown to revert at a very high frequency after treatment with 5-azacytidine. This suggested that there was a methylated xrs+ gene in these strains which was structurally intact, but not expressed. The xrs strains did not complement one another, and the locus was autosomally located. In view of the frequency of their isolation and their somewhat different phenotypes, we propose that the xrs strains are mutants derived from an active wild-type gene. However, there is in addition a methylated silent gene present in the genome. Azacytidine treatment reactivated this gene. We present a model for the functional hemizygosity of mammalian cell lines, which is based on the inactivation of genes by de novo hypermethylation. In contrast to results with xrs strains, other repair-defective lines were found not to be reverted by azacytidine.

Goal setting in neurological rehabilitation: patients' perspectives.

PURPOSE: Goal setting has been described as the core skill of rehabilitation professionals, but there is little information about patients understanding of goal setting. This study explored how in-patients with neurological impairments experienced two different types of goal setting and identified the issues that underpin individuals' experience of goal setting. METHOD: The study took place in a neurological rehabilitation unit in which two approaches to goal setting were being used that differed in the amount of patient involvement. A qualitative research design was adopted. Six focus groups were convened, three for participants experiencing usual participation and three for those with increased involvement in goal setting. A total of 28 participants (12 women, mean age 49 years) with a variety of deficits were recruited to the study over nine months. Thematic analysis was used to analyse the focus group transcripts. FINDINGS: Four themes were identified which impact on the ways in which in-patients make sense of goal setting: The rehabilitation process; personal response to goal setting; previous experience and disease limitations. CONCLUSIONS: Healthcare professionals working in rehabilitation need to explore patients' understandings of their disease and their experiences and expectations of goal setting to ensure goal setting is a meaningful activity.