Incorporating HIV/hepatitis B virus/hepatitis C virus combined testing into routine blood tests in nine UK Emergency Departments: the "Going Viral" campaign.

OBJECTIVES: Routine HIV screening is recommended in those UK hospitals and primary care settings where the HIV prevalence is > 0.2%. For hepatitis B virus (HBV) and hepatitis C virus (HCV), however, testing is targeted at at-risk groups. We investigated the prevalence of these blood-borne viruses (BBVs) during a routine testing pilot in UK Emergency Departments (EDs). METHODS: During the "Going Viral" campaign (13-19 October 2014), nine UK EDs in areas of high HIV prevalence offered routine tests for HIV, HBV and HCV to adults having blood taken as part of routine care. Patients who tested positive were linked to care. RESULTS: A total of 7807 patients had blood taken during their ED visit; of these, 2118 (27%) were tested for BBVs (range 9-65%). Seventy-one BBV tests were positive (3.4%) with 32 (45.1%) new diagnoses. There were 39 HCV infections (15 newly diagnosed), 17 HIV infections (six newly diagnosed), and 15 HBV infections (11 newly diagnosed). Those aged 25-54 years had the highest prevalence: 2.46% for HCV, 1.36% for HIV and 1.09% for HBV. Assuming the cost per diagnosis is £7, the cost per new case detected would be £988 for HCV, £1351 for HBV and £2478 for HIV. CONCLUSIONS: In the first study in the UK to report prospectively on BBV prevalence in the ED, we identified a high number of new viral hepatitis diagnoses, especially hepatitis C, in addition to the HIV diagnoses. Testing for HIV alone would have missed 54 viral hepatitis diagnoses (26 new), supporting further evaluation of routine BBV testing in UK EDs.

Stem cell-based treatments for Type 1 diabetes mellitus: bone marrow, embryonic, hepatic, pancreatic and induced pluripotent stem cells.

Type 1 diabetes mellitus--characterized by the permanent destruction of insulin-secreting ß-cells--is responsive to cell-based treatments that replace lost ß-cell populations. The current gold standard of pancreas transplantation provides only temporary independence from exogenous insulin and is fraught with complications, including increased mortality. Stem cells offer a number of theoretical advantages over current therapies. Our review will focus on the development of treatments involving tissue stem cells from bone marrow, liver and pancreatic cells, as well as the potential use of embryonic and induced pluripotent stem cells for Type 1 diabetes therapy. While the body of research involving stem cells is at once promising and inconsistent, bone marrow-derived mesenchymal stem cell transplantation seems to offer the most compelling evidence of efficacy. These cells have been demonstrated to increase endogenous insulin production, while partially mitigating the autoimmune destruction of newly formed ß-cells. However, recently successful experiments involving induced pluripotent stem cells could quickly move them into the foreground of therapeutic research. We address the limitations encountered by present research and look toward the future of stem cell treatments for Type 1 diabetes.

Noncontact ultrasound imaging applied to cortical bone phantoms.

PURPOSE: The purpose of this paper was to take the first steps toward applying noncontact ultrasound (NCU) to the tasks of monitoring osteoporosis and quantitative ultrasound imaging (QUS) of cortical bone. The authors also focused on the advantages of NCU, such as its lack of reliance on a technologist to apply transducers and a layer of acoustical coupling gel, the ability of the transducers to operate autonomously as specified by preprogrammed software, and the likely reduction in statistical and systematic errors associated with the variability in the pressure applied by the clinician to the transmitting transducer that NCU might provide. The authors also undertook this study in order to find additional applications of NCU beyond its past limited usage in assessing the severity of third degree burns. METHODS: A noncontact ultrasound imaging system using a pair of specially designed broadband, 1.5 MHz noncontact piezoelectric transducers and cortical bone phantoms, were used to determine bone mineral density (BMD), speed of sound (SOS), integrated response (IR), and ultrasonic transmittance. Air gaps of greater than 3 cm, two transmission and two reflection paths, and a digital signal processor were also used in the collection of data from phantoms of nominal mass densities that varied from 1.17 to 2.25 g/cm(3) and in bone mineral density from 0 to 1.7 g/cm(3). RESULTS: Good correlations between known BMD and measured SOS, IR, and transmittance were obtained for all 17 phantoms, and methods for quantifying and minimizing sources of systematic errors were outlined. The BMD of the phantom sets extended through most of the in vivo range found in cortical bone. A total of 16-20 repeated measurements of the SOS, thickness, and IR for the phantom set that were conducted over a period of several months showed a small variation in the range of measurements of ±1%-2%. These NCU data were shown to be in agreement with similar results using contact ultrasound to be within 1%-2%. Transmittance images of cortical bone phantoms showed differences in the nominal overall BMD values of the phantoms that were large enough to be distinguished by a visual examination. A list of possible sources of errors in quantitative NCU was also included in this study. CONCLUSIONS: The results of this paper suggest that NCU might find additional applications in medical imaging, beyond its original and only previous usage in assessing third degree burns. The fact that the authors' phantom measurements using conventional, gel coupled ultrasound are in agreement with those obtained with NCU demonstrates that in spite of large additional levels of attenuation of up to 150 dB and new error sources, NCU could have comparable levels of accuracy to those of conventional quantitative ultrasound, while providing the medical and patient comfort-related advantages of not involving direct contact.

The occurrence of periodontitis-related microorganisms in relation to titanium implants.

The peri-implant space was examined for the presence of periodontitis-related microorganisms in 19 patients. All patients had been fitted with osseointegrated titanium implants which were clinically sound at the time of examination and all had been prescribed daily 0.2% chlorhexidine mouthrinse. In 17 patients, two contralateral fixtures in patients were selected, the remaining 2 patients had only one fixture, and associated mucosal clinical variables assessed for plaque accumulation, gingival inflammation, bleeding tendency, and probing depth. The bacteriological composition of submucosal plaque samples was investigated using non-selective media and selective media for Actinobacillus actimomycetemcomitans (Aa), Porphyromonas gingivalis (Pg), and Prevotella intermedia (Pi). The peri-implant tissues were healthy. Twenty-two of 37 sites had a greater proportion of anaerobes than aerobes. Aa was detected at one site. Pg was not cultivated, and Pi was present in 7 of 37 sites, comprising between 0.4% and 60.9% of the total anaerobic viable counts. Since the presence of any of these organisms may play a contributory role to the loss of the fixture, it is recommended that the submucosal plaque of implants be monitored regularly for the presence of these periodontitis-associated species.

Dentifrice abrasivity and cervical dentinal hypersensitivity. Results 12 weeks following cessation of 8 weeks' supervised use.

Following an 8-week controlled investigation of 2 strontium chloride hexahydrate dentifrices (SCH) of differing abrasivity, 2 groups of 20 subjects each, with cervical dentinal hypersensitivity, were re-examined at 20 weeks; that is, 12 weeks after the active period. The examination procedures were conducted in the same manner as in the main clinical trial. Sensitivity levels were assessed by 2 instrument methods: tactile (Yeaple probe), and cold air (dental air syringe), and by subjective perception of pain by means of a Visual Analogue Scale. The results from these methods of assessment demonstrated that 12 weeks following the cessation of 8 weeks' controlled use of standard and low abrasive SCH dentifrices, sensitivity levels reversed on slightly in both groups and, overall, sensitivity remained significantly lower than at baseline. The abrasivity of the dentifrice did not affect the desensitivity activity.

Comparison of 2 desensitizing dentifrices with a commercially available fluoride dentifrice in alleviating cervical dentine sensitivity.

Previous studies have demonstrated efficacy of desensitizing dentifrices containing strontium acetate/sodium fluoride (SrAc2F) and potassium chloride/sodium monofluorophosphate (KCl/MFP) in alleviating discomfort arising from cervical dentine sensitivity (CDS). The aim of this investigation, therefore, was to determine efficacy of a SrAc2F dentifrice compared with KCl/MFP and a commercially available fluoride dentifrice containing sodium fluoride/sodium monofluorophosphate (NaMFP). Fifty-six patients participated in a 2-center double-blind, 3-way comparative parallel 6-week clinical study. Patients were evaluated at 0, 2, and 6 weeks for tactile (Yeaple probe), air sensitivity (dental air syringe), and subjective perception of pain (VAS scores). Results for Yeaple probe scores (Wilcoxon tests) between 2 weeks and baseline were highly significant for KCl/MFP, significant for NaMFP and nonsignificant for SrAc2F; scores between 6 weeks and baseline were, however, highly significant for all groups. Subjective Yeaple probe VAS scores (paired t-tests) between 6 weeks and baseline were significant for all groups; significance was demonstrated in the KCl/MFP group between 2 weeks and baseline. Subjective air visual analogue scores (paired t-tests) between 2 weeks and baseline were highly significant for all groups. There were no significant differences between groups at any time point. The results of the study demonstrated that the commercially available fluoride-containing dentifrice was as effective as the 2 desensitizing dentifrices in alleviating CDS over time.

Quantitative relationships between perceived and objective need for health care--dentistry as a model.

To elaborate and refine a previously devised method for quantifying the relationship between perceived and objectively determined dental disease, data on a random sample of 588 patients in two towns in England were analyzed. The data included the number of decayed (D), missing (M), and filled (F) teeth, composite DMF scores, and patients' self-assessments of the state of their teeth and the need for treatment. The study method was a combination of bioassay and psychophysical techniques. Categorical self-assessments of the state of teeth and the need for treatment were dichotomized to yield proportions, which, when transformed into logits, resulted in a linear relation to increments of dental disease. A 50% point for each of the component D, M, and F scores was derived from the intercept of the line of best fit. The D50 for both the state of teeth and the need for treatment was found to be closest to the objective measure (Dx), with the smallest standard error. Although males had a significantly lower D50 (0.5) than females (D50=2.1) for need for treatment, with no differences in D50 for state of teeth, the females actually had a significantly lower Dx. These data indicate that males as a group had a lower threshold for perception of the need for treatment. This finding contrasts with the observation in other studies that males actually use dental services less than females.

Transfer of child patients from the Community Dental Service to the General Dental Service. Experiences within Wycombe Health Authority.

A system for monitoring the transfer of child patients from the Community Dental Service to general dental practitioners within the Wycombe Health Authority area in conformity with the requirements of Government Circular HC(89)2 is described. The investigation extended over a four-month period, from February to May 1990, with a follow-up of referrals from October 1990 to January 1991. During this period 3,407 child patients completed courses of treatment within the community service, of whom 636 were eligible for transfer. Of these only 62 were successfully transferred to general dental practitioners.

The role of the community pharmacist as a dental health adviser.

In this study 409 community pharmacists answered a questionnaire about the number and nature of their customers' inquiries regarding oral health and topics related to dentures. Three-quarters of respondents were asked, at least once a week, for advice on a wide range of such matters. The results indicate that pharmacists' knowledge is poor and it is therefore concluded that more material concerning oral health should be given in their undergraduate and postgraduate education. The general public would benefit substantially.

A pilot assessment of alternative methods of quantifying dental pain with particular reference to dentine hypersensitivity.

OBJECTIVE: The overall aim of this pilot study was to establish the usefulness and comparability of selected verbal and non-verbal methods in the quantification of sensory and affective aspects of dental pain associated with dentine hypersensitivity (DH). DESIGN: The assessment of dental pain was conducted during an eight week clinical study. Patients were asked to rate their perception of dental pain using selected methods of quantification following tactile (Yeaple Probe-an electronic pressure-sensitive probe) and evaporative (cold air from a dental air syringe) stimulation; together with an overall assessment of perception to daily stimuli (e.g., cold air/water, toothbrushing, sweet and sour foods). The assessment methods used to quantify pain arising from DH were a continuous visual analogue scale (VAS), a 0-10 numerical rating VAS scale (NRS), and a separate intensity verbal descriptor (IVD) and unpleasantness verbal descriptor (UVD) word scales. SETTING: A specialist department at a postgraduate dental institute and hospital in London, UK. SUBJECTS: Twenty-five adult patients (8M + 17F) with a mean age of 42.6 years (95 per cent C.I. 38.8 to 46.4 years) attending the department for a clinical study evaluating the efficacy of a desensitising toothpaste agreed to participate. OUTCOME MEASURES: The study compared a continuous visual analogue scale (VAS), a 0-10 numerical rating visual analogue scale (NRS), and a separate intensity (IVD) and unpleasantness verbal descriptor (UVD) scales to quantify sensory and affective aspects of pain. An unweighted moving average technique was used to construct graphs of the relative frequency of reported severity gradings over a range of 0-10. RESULTS: The results of the study indicated that cold air appeared to cause greater discomfort to the patient than tactile sensitivity, with the air intensity curve for both IVD and 0-10 VAS peaking at a severity score of 5 while continuous VAS peaked at a score of 3-4. All methods peaked at score 2 for tactile sensitivity. The UVD scale peaked at score 2-3 and again at 6 for air sensitivity, but conformed to the other scales by peaking at score 2 for tactile sensitivity. NRS and IVD scales therefore appeared to provide acceptable alternatives to continuous VAS, but the UVD scale, probably because of the imprecise nature of the words used in the scale, did not. CONCLUSIONS: This study partially confirms previous conclusions that both verbal and non-verbal techniques quantify sensory and affective aspects of pain. However, the imprecise nature of UVD words provided misleading information in terms of both accuracy and sensitivity (except at very low levels of discomfort), when assessing pain arising from dentine hypersensitivity. In view of the highly subjective data arising from studies of this nature, the use of a moving average technique may be considered a more pragmatic method of analysis.

Is modelling dental caries a 'normal' thing to do?

OBJECTIVE: To introduce and encourage the use of generalised linear models (GLMs) in analysing caries data that do not require the response to be treated necessarily as a sample from a normal distribution. BASIC RESEARCH DESIGN: At the present time, it is most likely that the sampling distribution of dmf/DMF in industrialised countries will not approximate normality. Generalised linear modelling can be conducted assuming many underlying distributions which, in fact, includes the normal distribution. In this paper three GLMs are employed (normal, Poisson, negative binomial) for modelling an example caries data set. In addition, a binomial model is used to model the dichotomous outcome of caries-free/caries-present. CLINICAL SETTING: The data comprised 871 Old Trafford, Manchester primary school children aged between 4 years 0 months and 5 years 11 months. RESULTS: The effect of one study covariate was prominent in a normal model applied to all available dmf data but not in two non-normal models which used dmf > 0 data only. Furthermore, the same covariate was significant at the 5% level in a binomial model indicating that it influenced whether or not caries was present and not the level of dmf. CONCLUSION: A suitable modelling approach for caries data is to employ a Poisson or a negative binomial model for the dmf/DMF response and a binomial model for the caries-free/caries-present outcome. This allows separate estimation of those factors which influence the magnitude of caries and those factors which influence whether caries is actually present or not.

Simple summary calculations.

Methods of measuring the general magnitude or central tendency of sets of data are described, including the mean, median and mode. Similarly, methods of determining the degree of dispersion of the observations about the mean, including range, variance, and standard deviation are presented, together with worked practical examples of their use and importance. The use of algebraic notation in statistics is described.

Probability and sampling.

The concept of probability is introduced, and the role of probability distributions in statistical theory is discussed, with particular reference to the Normal distribution and its characteristics. Sampling and sampling variation are described, together with sampling error, the standard error of the mean, and confidence intervals for determining the likely magnitude of a population mean.

Descriptive statistics.

The importance of a knowledge of statistical methods in relation to most aspects of dentistry is discussed. Definitions of terms used in descriptive statistical techniques are provided, together with a review of the techniques themselves.

The effect of increasing vertical dimension of occlusion on facial aesthetics.

AIM: To investigate the effect of increasing the vertical dimension of occlusion on facial aesthetics. SETTING: General practice. METHOD: Questionnaires were sent to 96 patients who had been treated in the practice during the period of July 1998 to December 2000, resulting in an overall 72% response rate. All these patients had had their occlusal vertical dimension increased. Photographs of patients were taken before, during and after treatment. The questionnaire asked their opinion on the effects of the treatment on their facial features. To obtain an objective view to substantiate the opinions of the patients, a panel of five judges reviewed the before and after photographs and filled in their own questionnaires. RESULTS: Of the patients who responded to the questionnaire, 79.7% said they looked younger after the treatment. The panel thought 81.2% of the patients treated whose photographs they reviewed looked younger. CONCLUSION: Increasing the vertical dimension of occlusion can have far reaching effects on facial aesthetics, not just on the peri-oral areas but on the whole face.

Significance tests.

Simple methods of determining whether the difference between a sample mean and a given standard value is likely to be due only to sampling error, or to be real and/or of practical importance, are described. The use of the null hypothesis and of standard normal deviates is discussed, and examples are provided to illustrate the points made.

Comparison of several groups.

Techniques for the comparison of several samples are described. If the response is quantitative, comparison of the sample means is achieved by one-way analysis of variance. If the response is qualitative, comparison of several proportions is achieved by chi 2 tests.

Analysing the association between two variables.

Techniques of linear regression and correlation analysis are discussed and illustrated by means of dentally-related examples.

Significance tests. Part 2.

The comparison of two means obtained from either small or large samples and the comparison of two proportions is described, together with the use of logarithmic transformation of quantitative data in order to stabilise variance.