Variations in survival time for amalgam and resin composite restorations: a population based cohort analysis.

OBJECTIVE: To estimate the association between the restorative material used and time to further treatment across population cohorts with universal coverage for dental treatment. BASIC RESEARCH DESIGN: Cohort study of variation in survival time for tooth restorations over time and by restoration material used based on an Accelerated Failure Time model. CLINICAL SETTING: Primary dental care clinics. PARTICIPANTS: Members of Canada's First Nations and Inuit population covered by the Non-Insured Health Benefits program of Health Canada for the period April 1, 1999 to March 31, 2012. INTERVENTION: Tooth restorations using resin composite or amalgam material. MAIN OUTCOME: Survival time of restoration to further treatment. RESULTS: Median survival time for resin composite was 51 days longer than amalgam, for restorations placed in 1999-2000. This difference was not statistically significant (p⟩0.05). Median survival times were lower for females, older subjects. Those visiting the dentist annually, and decreased monotonically over time from 11.2 and 11.3 years for resin composite and amalgam restorations respectively placed in 1999-2000 to 6.9 and 7.0 years for those placed in 2009-10. CONCLUSIONS: Resin composite restorations performed no better than amalgams over the study period, but cost considerably more. With the combination of the overall decrease in survival times for both resin composite and amalgam restorations and the increase in use of resin composite, the costs of serving Health Canada's Non-Insured Health Benefits population will rise considerably, even without any increase in the incidence of caries.

Predicting the concentration of verotoxin-producing Escherichia coli bacteria during processing and storage of fermented raw-meat sausages.

A model to predict the population density of verotoxigenic Escherichia coli (VTEC) throughout the elaboration and storage of fermented raw-meat sausages (FRMS) was developed. Probabilistic and kinetic measurement data sets collected from publicly available resources were completed with new measurements when required and used to quantify the dependence of VTEC growth and inactivation on the temperature, pH, water activity (aw), and concentration of lactic acid. Predictions were compared with observations in VTEC-contaminated FRMS manufactured in a pilot plant. Slight differences in the reduction of VTEC were predicted according to the fermentation temperature, 24 or 34°C, with greater inactivation at the highest temperature. The greatest reduction was observed during storage at high temperatures. A population decrease greater than 6 decimal logarithmic units was observed after 66 days of storage at 25°C, while a reduction of only ca. 1 logarithmic unit was detected at 12°C. The performance of our model and other modeling approaches was evaluated throughout the processing of dry and semidry FRMS. The greatest inactivation of VTEC was predicted in dry FRMS with long drying periods, while the smallest reduction was predicted in semidry FMRS with short drying periods. The model is implemented in a computing tool, E. coli SafeFerment (EcSF), freely available from http://www.ifr.ac.uk/safety/EcoliSafeFerment. EcSF integrates growth, probability of growth, and thermal and nonthermal inactivation models to predict the VTEC concentration throughout FRMS manufacturing and storage under constant or fluctuating environmental conditions.

The relationship between ADHD and key cognitive phenotypes is not mediated by shared familial effects with IQ.

BACKGROUND: Twin and sibling studies have identified specific cognitive phenotypes that may mediate the association between genes and the clinical symptoms of attention deficit hyperactivity disorder (ADHD). ADHD is also associated with lower IQ scores. We aimed to investigate whether the familial association between measures of cognitive performance and the clinical diagnosis of ADHD is mediated through shared familial influences with IQ. METHOD: Multivariate familial models were run on data from 1265 individuals aged 6-18 years, comprising 920 participants from ADHD sibling pairs and 345 control participants. Cognitive assessments included a four-choice reaction time (RT) task, a go/no-go task, a choice-delay task and an IQ assessment. The analyses focused on the cognitive variables of mean RT (MRT), RT variability (RTV), commission errors (CE), omission errors (OE) and choice impulsivity (CI). RESULTS: Significant familial association (rF) was confirmed between cognitive performance and both ADHD (rF=0.41-0.71) and IQ (rF=-0.25 to -0.49). The association between ADHD and cognitive performance was largely independent (80-87%) of any contribution from etiological factors shared with IQ. The exception was for CI, where 49% of the overlap could be accounted for by the familial variance underlying IQ. CONCLUSIONS: The aetiological factors underlying lower IQ in ADHD seem to be distinct from those between ADHD and RT/error measures. This suggests that lower IQ does not account for the key cognitive impairments observed in ADHD. The results have implications for molecular genetic studies designed to identify genes involved in ADHD.

Light sensitivity and pain sensation during cataract surgery. A comparative study of two modes of anaesthesia.

The objective of this study was to compare the light sensitivity and pain experienced by patients undergoing cataract surgery under subtenon and topical with intracameral anaesthesia. Fifty-four patients were randomly assigned to receive either two drops of proxymethacaine 0.5% as topical anaesthesia with 0.5 ml preservative-free 1% intracameral lidocaine or 4 ml 2% lignocaine as subtenon anaesthesia. Light sensitivity and overall pain perception were recorded at the end of surgery. The mean pain score in the subtenon group (0.11; range 0-1) was lower than in the topical group (1.07; range: 0-3, P < 0.001). The mean light-sensitivity score was lower in the subtenon group (0.26; range: 0-4) than in the topical group (1.29; range: 0-4, P = 0.001). Subtenon anaesthesia was more effective in suppressing light sensitivity and pain during cataract surgery than topical with intracameral anaesthesia. This suggests that use of subtenon anaesthesia may lead to a more comfortable operative experience.

Role of the fractalkine receptor CX3CR1 polymorphisms V249I and T280M as risk factors for early-onset coronary artery disease in patients with no classic risk factors.

OBJECTIVES: CX3CR1 is a monocyte chemokine receptor and adhesion molecule. Two CX3CR1 mutations, V249I and T280M, reportedly decrease coronary artery disease (CAD) risk independent of established risk factors. An I249 protective effect is attributed to reducing CX3CR1 binding to fractalkine, its ligand. MATERIAL AND METHODS: We examined the frequencies of V249I and T280M among early-onset CAD patients (G1; n = 149; <50 years), late-onset CAD patients (G2; n = 150; >65 years) and healthy controls (HC; n = 149, 47-93 years) without known CAD risk factors. We compared plasma total cholesterol (TC)/high density lipoprotein-C (HDL-C) and apolipoprotein B (APOB)/apolipoprotein AI (APOAI) ratios among the groups and mutation carriers and non-carriers, and the prevalence of the mutations in G1 and G2 patients with multiple coronary vessel disease (MVD) and myocardial infarction (MI). RESULTS: G1 patients had non-significantly lower frequencies of I249 versus (vs.) G2 or controls (G1; 51 %, G2: 61 %, controls: 58 %, p = 0.19), with no difference in T280M (p = 0.8). TC/HDL-C and APOB/APOAI ratios were significantly higher in G1 patients vs. G2 and controls (p<0.0001) independently of either mutation. More G2 patients had MVD than younger ones (p<0.0001); however, more G1 patients were homozygous for V249 compared to G2 patients, who more often had the I249 allele (p<0.02). There was no such association with T280M (p = 0.38). Although more G1 patients had MI, this was not mutation related. CONCLUSIONS: There were significantly higher lipid ratios in G1 compared to G2 and HC (G1>G2>HC), but not in mutation prevalence. I249 mutation was associated with MVD in older patients, while V249 homozygosity was associated with the early-onset CAD. Neither allele affected MI or lipid levels.

The relationship between patients' experiences of continuity of cancer care and health outcomes: a mixed methods study.

It is difficult to define continuity of care or study its impact on health outcomes. This study took place in three stages. In stage I we conducted qualitative research with patients, their close relatives and friends, and their key health professionals from which we derived a number of self completion statements about experienced continuity that were tested for reliability and internal consistency. A valid and reliable 18-item measure of experienced continuity was developed in stage II. In stage III we interviewed 199 patients with cancer up to five times over 12 months to ascertain whether their experiences of continuity were associated with their health needs, psychological status, quality of life, and satisfaction with care. The qualitative data revealed that experienced continuity involved receiving consistent time and attention, knowing what to expect in the future, coping between service contacts, managing family consequences, and believing nothing has been overlooked. Transitions between phases of treatment were not associated with changes in experienced continuity. However, higher experienced continuity predicted lower needs for care, after adjustment for other potential explanatory factors (standardised regression coefficients ranging from -0.12 (95% CI -0.20, -0.05) to -0.32 (95% CI -0.41, -0.23)). Higher experienced continuity may be linked to lower health care needs in the future.

A survey of investigations used for the management of glaucoma in hospital service in the United Kingdom.

AIMS: This study surveys the current use of investigations for the management of glaucoma in hospital practice by UK ophthalmologists. METHODS: A total of 1007 questionnaires were posted to all active NHS consultant ophthalmologists. They were asked to indicate the type of hospital (whether university (UTH) or general (DGH) hospital), glaucoma specialist status, and availability and use of automated perimetry, disc photography, HRT, GDx, OCT, and pachymetry. RESULTS: A total of 493 completed questionnaires were received and 469 were analysed: 284 (60.6%) DGH, 185 (39.4%) UTH, 144 (30.7%) glaucoma specialists. There was good availability of automated perimetry (467, 99.6%), disc photography (420, 89.6%), pachymetry (374, 79.7%), OCT (212, 45.2%), HRT (206, 43.9%), and GDx (59, 12.6%). A total of 308 (65.7%) consultants had at least one digital imaging instrument available. The majority of consultants used SAP (347, 74.0%) and SITA-fast (282, 60.1%) for glaucoma suspects, and for monitoring glaucoma (283, 60.3% and 197, 42.0%, respectively). Some used Esterman (155, 33.0%) and Goldmann fields (90, 19.2%) in addition to SAP and SITA-fast for glaucoma suspects. Few consultants used short-wavelength automated perimetry and frequency-doubled perimetry. Of the three imaging tests, HRT was the most commonly used investigation for disc asymmetry, early glaucoma, glaucomatous progression, ocular hypertension, normal tension glaucoma, and unreliable visual fields (P<0.0001). Where pachymeters were available, 333 (89.0%) consultants and 117 (98.3%) glaucoma specialists used pachymetry in glaucoma management. CONCLUSIONS: There was some variation in the use of investigations for the diagnosis and management of glaucoma, reflecting the range of techniques available. SAP, SITA-fast, and pachymetry were the most commonly utilised investigations followed by HRT. Glaucoma specialist status, type of hospital, and presence of research influenced the availability and use of all investigations, except visual fields.

Optochiasmal avulsion secondary to minor occipital trauma.

BACKGROUND: Optic nerve avulsion is an extremely rare occurrence and usually arises in the setting of severe fronto-orbital fractures or penetrating orbital injuries. However, a few cases have been associated with minor injury. OBJECTIVE: To overview the pathophysiology of delayed optochiasmal avulsion following minor ocipital trauma and discuss management options. METHODS: Report of a unique case of a 79-year-old woman who presented with delayed partial expulsion of the right globe and complete optic nerve avulsion following closed head injury to the occiput. CONCLUSION: Antero-posterior distortion of the skull following such a deceleration injury can cause laceration and thrombosis of the pre-chiasmal and pial arteries supplying the optic chiasm. The ensuing ischaemic changes subsequently caused delayed softening of the chiasm and its avulsion. The concomitant retrobulbar haemorrhage and mass effect within the orbit consequently led to the partial expulsion of the globe.

A comparison of HRT II and GDx imaging for glaucoma detection in a primary care eye clinic setting.

PURPOSE: To evaluate the performance of the HRT II (Heidelberg retinal tomograph) and GDx (glaucoma detection) retinal nerve fibre analyzer in GDx when used in the primary care eye clinic setting for glaucoma screening. PATIENTS AND METHODS: The study was prospective, cross-sectional, and hospital-based. One-hundred and twelve patients, 59 women and 53 men with a mean age of 57.8 years (range 18-85 years), had consecutive HRT II disc imaging and GDx retinal nerve fiber layer analysis. The Moorfield's regression classification and the 'GDx number' were used to predict the likelihood of glaucoma. A separate clinician, masked to the instrument results determined a definitive diagnosis, based on clinical examination. The extent of agreement between instrument prediction and the clinician diagnosis of glaucoma was examined by generating sensitivity and specificity tables. RESULTS: The HRT II had a sensitivity of 0.79 (95% CI: 0.60-0.92) and a specificity of 0.70 (95% CI: 0.60-0.78). The positive predictive value of the HRT II was 0.43 (95% CI: 0.29-0.57). Using a GDx number of 50 as 'cutoff' for glaucoma detection, the GDx had a sensitivity of 0.80 (95% CI: 0.59-0.93) and a specificity of 0.72 (95% CI: 0.61-0.80), with a positive predictive value of 0.43 (95% CI: 0.28-0.59). CONCLUSIONS: For glaucoma detection, neither the HRT II nor the GDx are effective as stand-alone screening devices in the primary care setting.

The analysis of 51 genes in DSM-IV combined type attention deficit hyperactivity disorder: association signals in DRD4, DAT1 and 16 other genes.

Attention deficit hyperactivity disorder (ADHD) is a common neurodevelopmental disorder, starting in early childhood and persisting into adulthood in the majority of cases. Family and twin studies have demonstrated the importance of genetic factors and candidate gene association studies have identified several loci that exert small but significant effects on ADHD. To provide further clarification of reported associations and identify novel associated genes, we examined 1,038 single-nucleotide polymorphisms (SNPs) spanning 51 candidate genes involved in the regulation of neurotransmitter pathways, particularly dopamine, norepinephrine and serotonin pathways, in addition to circadian rhythm genes. Analysis used within family tests of association in a sample of 776 DSM-IV ADHD combined type cases ascertained for the International Multi-centre ADHD Gene project. We found nominal significance with one or more SNPs in 18 genes, including the two most replicated findings in the literature: DRD4 and DAT1. Gene-wide tests, adjusted for the number of SNPs analysed in each gene, identified associations with TPH2, ARRB2, SYP, DAT1, ADRB2, HES1, MAOA and PNMT. Further studies will be needed to confirm or refute the observed associations and their generalisability to other samples.

Quality of life in thalassemia.

Morbidity and mortality related to thalassemia have been reduced significantly with modern medical treatment, and quality of life (QOL) should now be considered an important index of effective health care. An assessment of QOL differs from other forms of medical assessment in that it focuses on the individuals' own views of their well-being and assesses other aspects of life, giving a more holistic view of well-being. There is very little published work on evaluation of QOL in thalassemia. A suitable tool should be reproducible, sensitive to the major features of the condition that affect patients' lives, and applicable in the range of different cultural, age, and social settings. Such an instrument would be valuable in evaluating new forms of treatment and in comparing health outcomes between different clinics. Two instruments have been assessed, one derived from the WHOQOL-100 questionnaire, and one designed specifically for thalassemia, which assesses psychosocial and clinical burden, as they affect adult patients, parents, and children. Further studies are required to develop and assess such tools for use in thalassemia. Another approach is to seek patients' own views of their routine treatment and the extent to which medical treatment affects QOL. Results from patient questionnaires in the United Kingdom and Cyprus are consistent in finding problems with organization of transfusions, insufficient options with chelation therapy, and poor communication. Practical measures could be taken to address these issues.

Visual perception during phacoemulsification cataract surgery under subtenons anaesthesia.

AIM: The aim of this study was to record the subjective visual experience of patients during phacoemulsification and intraocular lens implantation under subtenons anaesthesia. METHODS: Prospective, nonrandomised, cohort, postoperative questionnaire based study. Patients selected underwent routine phacoemulsification and intraocular lens implantation under regional subtenons anaesthesia. chi(2) and Fisher's exact tests (two-tail) were used to evaluate the data. RESULTS: A total of 104 patients were selected, 38 (36.5%) were male and 66 (63.5%) were female. The mean age of patients was 74.0+/-8.8 years. In all, 87.5% saw light during the operation with 9.6% finding this painful. Photophobia was highest among younger patients (P=0.002). Coloured lights were seen by 56.7% and 13.5% found the visual experience frightening. Frightening visual experiences were significantly associated with the perception of colour (P=0.005) and photophobia (P=0.003). A volume of anaesthetic greater than 4 m was associated with a significant reduction in anxiety as a result of the visual experience (P=0.003). None of the other visual phenomena recorded were associated with a frightening visual experience. CONCLUSIONS: Patients undergoing regional anaesthesia experience a wide variety of visual sensations during cataract surgery. Perception of colour and volumes of anaesthetic less than 4 m appear to be associated with the visual experience being more frightening. Detailed preoperative counselling is mandatory. It should include comprehensive information about visual perception during the procedure relieving the patients from unnecessary distress.

Interchangeability of two semiadjustable articulators.

PURPOSE: Interchangeability between articulators allows mounted casts to be transferred accurately from one articulator to another. The purpose of this study was to evaluate the interchangeability of 109 new, unused interchangeable articulators in the centric position. MATERIALS AND METHODS: The interchangeability of 38 unused Whip Mix model #2240 and 71 unused model #3040 semiadjustable articulators was evaluated using the Whip Mix #2245 check system as the standard. Vertical discrepancies between the check system cylinders were also measured. RESULTS: Within the standard for interchangeability established by the Whip Mix #2245 check system (< 94 microns horizontal discrepancy), 101 (93%) of 109 articulators were interchangeable (34 were model #2240 and 67 were model #3040). Overall, the amount of vertical space between the check system cylinders was < or = 52 microns in 99.4% of the model #2240 articulators and 99.7% of the #3040 articulators. CONCLUSION: New, unused Whip Mix model #2240 and #3040 articulators are potentially interchangeable in the centric position.

Bone marrow mobilized with granulocyte colony-stimulating factor in related allogeneic transplant recipients: a study of 29 patients.

We studied whether a short course of granulocyte colony-stimulating factor (G-CSF) administered to normal donors immediately before bone marrow (BM) harvest would shorten time to neutrophil and platelet engraftment in matched related allogeneic BM recipients. Twenty-nine normal donors received 4 consecutive daily subcutaneous injections of G-CSF (median dose, 12.1 microg/kg per day; range, 9.6-15.7 microg/kg per day) immediately before BM harvest. Donors tolerated G-CSF well, with only mild myalgias and arthralgias, and BM was easy to aspirate. The BM harvest contained a median of 5.3 x 10(8) white blood cells (WBCs)/kg (range, 3.1-11.1 x 10(8) WBCs/kg) and 2.5 x 10(6) CD34+ cells per kg (range, 1.5-7.3 x 10(6) CD34+ cells per kg). Median times to neutrophil (18 days [range, 11-30 days] versus 22 days [range, 16-36 days]; P = .05) and platelet (22 days [range, 15-55 days] versus 27 days [range, 18-46 days]; P = .04) engraftment were statistically shorter than those of historical control subjects whose donors had not received G-CSF before BM harvest. However, secondary engraftment-dependent outcomes including red blood cell and platelet transfusions, febrile days, days on antibiotics, days from transplant to hospital discharge, and days in hospital during the first 60 days after transplant were not statistically different from historical control subjects. We conclude that G-CSF administered to normal donors immediately before harvest facilitates BM aspiration, increases the WBC content of the harvest, and hastens neutrophil and platelet engraftment compared with historical control subjects.

Interchangeability of semiadjustable articulators after 2 to 7 years of use.

PURPOSE: The purpose of this study was to test the interchangeability of articulators that had been in use from 2 to 7 years and compare these results with the interchangeability of the same articulators 1 year earlier. MATERIALS AND METHODS: Forty-six Whip Mix model #2240 articulators (Whip Mix Corporation, Louisville, KY) that were in clinical use from 2 to 7 years were checked for interchangeability using the Whip Mix #2245 check system. The horizontal tolerance of the check system was 94 microm. Articulators were also evaluated in the vertical dimension at 4 predetermined locations around the check system cylinders using 26-microm-thick shimstock. Vertical discrepancies between the cylinders were recorded as the thickness of 0, 1, 2, or more than 2 pieces of shimstock. Interchangeability results were compared with those determined 1 year previously using the same evaluation methods using the Exact McNemar's Test of Agreement (alpha = 0.05). RESULTS: Using the Whip Mix 2245 check system, 35 (76%) articulators were interchangeable after 2 to 7 years of use. This compares to 38 (83%) that were interchangeable upon evaluation 1 year earlier. The decrease in interchangeability was not significant (p =.4531). Forty-three (94%) of the articulators had vertical discrepancies of 52 microm or less at the initial evaluation. One year later, 45 (98%) of the articulators had vertical discrepancies of 52 microm or less. After 1 year, there were significant differences in the amount of vertical space between the cylinders only at the right side (p =.014). CONCLUSION: The Whip Mix model #2240 articulator can remain interchangeable during clinical use for 7 years, but should be routinely checked for calibration.

Effect of distance on the power density from two light guides.

PURPOSE: This study determined the effect of distance on the power density from standard and Turbo light guides (Demetron/Kerr, Danbury, Connecticut). MATERIALS AND METHODS: Power density was measured from 0 to 10 mm away from the tip of standard 8-mm curved light guides and 13/8-mm Turbo curved light guides. To determine the effect of distance on power density, a polynomial regression line was fitted. The Kolmogorov-Smirnov (K-S) statistic and the Wilcoxon rank sum (WR) tests were used to determine if there was a difference in the rate at which the power density decreased for the standard and Turbo light guides as the distance from the tip increased. Photographs of the light dispersion from each tip were also taken. RESULTS: At 0 mm, the mean (+/- SD) power density from the two standard light guides was 743 +/- 6.1 mW/cm2 and from the four Turbo light guides was 1128 +/- 22.1 mW/cm2. As the distance from the tip of the light-guide tip increased, the power density decreased, but the rate of decrease was greater from the Turbo light guides than from the standard light guides. At 6 mm the power density from the standard light guides fell to 372 mW/cm2 (50% of the original value) and the power density from the Turbo light guides fell to 263 mW/cm2 (23% of the original value). Both the K-S statistic and the WR sum test indicated that the distribution of light intensities was significantly different from the two light guides (WR p-value = .0246, K-S p-value < .0001). The two estimated polynomials intersected at 3.66 mm, and the 95% prediction intervals intersected at about 2.8 and 4.8 mm. Therefore, beyond 5 mm away from the tip of the light guide, the standard light guides gave higher power density readings than the Turbo light guides. Photographs showed that the light dispersed at a wider angle from the Turbo light guides than from the standard light guide. CLINICAL SIGNIFICANCE: The design of the light guide of a light curing unit affects light dispersion, power density, and ultimately the dentist's ability to properly cure composite. For these reasons, manufacturers should report the power density at the tip of the light guide and 6 mm from the tip of the light guide, since significant differences exist between light guide designs.