Girvan Burnside

A Randomized Trial of Genotype-Guided Dosing of Warfarin

BACKGROUND The level of anticoagulation in response to a fixed-dose regimen of warfarin is difficult to predict during the initiation of therapy. We prospectively compared the effect of genotype-guided dosing with that of standard dosing on anticoagulation control in patients starting warfarin therapy. METHODS We conducted a multicenter, randomized, controlled trial involving patients with atrial fibrillation or venous thromboembolism. Genotyping for CYP2C9*2, CYP2C9*3, and VKORC1 (-1639G→A) was performed with the use of a point-of-care test. For patients assigned to the genotype-guided group, warfarin doses were prescribed according to pharmacogenetic-based algorithms for the first 5 days. Patients in the control (standard dosing) group received a 3-day loading-dose regimen. After the initiation period, the treatment of all patients was managed according to routine clinical practice. The primary outcome measure was the percentage of time in the therapeutic range of 2.0 to 3.0 for the international normalized ratio (INR) during the first 12 weeks after warfarin initiation. RESULTS A total of 455 patients were recruited, with 227 randomly assigned to the genotype-guided group and 228 assigned to the control group. The mean percentage of time in the therapeutic range was 67.4% in the genotype-guided group as compared with 60.3% in the control group (adjusted difference, 7.0 percentage points; 95% confidence interval, 3.3 to 10.6; P<0.001). There were significantly fewer incidences of excessive anticoagulation (INR ≥4.0) in the genotype-guided group. The median time to reach a therapeutic INR was 21 days in the genotype-guided group as compared with 29 days in the control group (P<0.001). CONCLUSIONS Pharmacogenetic-based dosing was associated with a higher percentage of time in the therapeutic INR range than was standard dosing during the initiation of warfarin therapy. (Funded by the European Commission Seventh Framework Programme and others; ClinicalTrials.gov number, NCT01119300.).

A Randomised Controlled Trial of the Efficacy of Supervised Toothbrushing in High-Caries-Risk Children

Scottish children have one of the highest levels of caries experience in Europe. Only 33% of 5-year-old children in Dundee who developed caries in their first permanent molars by 7 brushed their teeth twice a day. High-caries-risk children should benefit if they brush more often with fluoridated toothpaste. The aim of this clinical trial was to determine the reduction in 2-year caries increment that can be achieved by daily supervised toothbrushing on school-days with a toothpaste containing 1,000 ppm fluoride (as sodium monofluorophosphate) and 0.13% calcium glycerophosphate, combined with recommended daily home use, compared to a control group involving no intervention other than 6-monthly clinical examinations. Five hundred and thirty-four children, mean age 5.3, in schools in deprived areas of Tayside were recruited. Each school had two parallel classes, one randomly selected to be the brushing class and the other, the control. Local mothers were trained as toothbrushing supervisors. Children brushed on school-days and received home supplies. A single examiner undertook 6-monthly examinations recording plaque, caries (D1 level), and used FOTI to supplement the visual caries examination. For children in the brushing classes, the 2-year mean caries increment on first permanent molars was 0.81 at D1 and 0.21 at D3 compared to 1.19 and 0.48 for children in the control classes (significant reductions of 32% at D1 and 56% at D3). In conclusion, high-caries-risk children have been shown to have significantly less caries after participating in a supervised toothbrushing programme with a fluoridated toothpaste.

An investigation of the relationship between untreated decayed teeth and dental sepsis in 5-year-old children.

Objectives To investigate the prevalence of dental sepsis in 5-year-old children in Scotland and the relationship between sepsis, treated and untreated decayed teeth, oral cleanliness (visible plaque on anterior teeth) and socio-economic deprivation.Subjects and methods Six thousand, nine hundred and ninety-four children of mean age 5.3 years were examined as part of a survey conducted under the Scottish Health Boards Dental Epidemiological Programme. The presence of dental sepsis was recorded, in addition to caries status, and presence of plaque. Postal code information was used to obtain a measure of material deprivation. Relationships between sepsis and its possible contributory factors were explored using stepwise logistic regression.Main results In the whole sample, 4.8% of children examined had dental sepsis, ranging from 2% in the most affluent areas to 11% in the most deprived. Children with sepsis had much higher caries experience (mean dmft 6.30) than those without sepsis (mean dmft 2.36). However, when these factors and the presence of plaque were entered into a logistic regression model to predict presence or absence of dental sepsis, the most important factor was not deprivation, but untreated decay.Conclusions The proportion of children with sepsis increases markedly with caries experience. This disadvantage can be mitigated if more of the caries experience is treated. These findings would not support a policy of non-intervention for deciduous caries if oral sepsis is to be minimised.

Dental anxiety, distress at induction and postoperative morbidity in children undergoing tooth extraction using general anaesthesia

Objective To report on the prevalence of postoperative morbidity in children undergoing tooth extraction under chair dental general anaesthetic (CDGA) in relation to pre-operative dental anxiety and anaesthetic induction distress.Design A prospective national study.Setting Twenty-five Scottish DGA centres in 2001.Subjects and method Four hundred and seven children (mean age 6.6 years; range: 2.3 to 14.8 years; 52% male). Before CDGA, the Modified Child Dental Anxiety (MCDAS) and Modified Dental Anxiety (MDAS) Scales were completed for children and accompanying adult respectively; the latter also returned a morbidity questionnaire 24 hours and one week post-operatively. Anaesthetic induction distress was scored immediately before CDGA induction using the Childrens Hospital of Eastern Ontario Pain Scale (CHEOPS).Results The mean MCDAS score was 24.2 (population norm 18.2); 21% of adults were anxious. Forty-two per cent of children had induction distress; this related to their MCDAS scores (r= 0.43, p<0.001, Pearson Product Moment Correlation Coefficient). Morbidity at 24 hours and seven days was 63% and 24% respectively; this related to MCDAS scores (r= 0.15, p=0.029 and r= 0.17, p= 0.009, Pearson Product Moment Correlation Coefficient) and to induction distress (chi2= 7.14, p= 0.007 and chi2= 11.70, p= 0.001).Conclusion The majority of children suffered next day morbidity and many still had symptoms a week later. Most children were dentally anxious; this related to induction distress and postoperative morbidity.

Assessment of perceptibility and acceptability of color difference of denture teeth.

OBJECTIVES To assess the color difference values that represent the perceptibility and acceptability thresholds of denture teeth. METHODS Eighteen interchangeable right upper central incisors denture teeth were selected to have color difference values from representative left upper central incisor denture tooth in a range of 0.4-11.4 ΔE* units measured with a spectrophotometer (CM 2600d, Minolta Konica, Japan). These teeth were placed in an artificial dental arch in a phantom head. Under controlled conditions, a total of 80 observers divided into 4 groups (technicians, nurses, dentists and researchers) were asked to report the perceptibility and acceptability of each of the color difference values. The findings was then analysed using logistic regression for determining the perceptible and acceptable thresholds of dental color differences. RESULTS The determined color difference values at which 50% of all observers could detect a color difference (50:50 probability) was 1.9 ΔE* units with a 95% confidence interval and ranged from 1.7 ΔE* units to 2.1 ΔE* units. The determined color difference value at which 50% of all observes preferred to replace the tooth because of unacceptable color difference (50:50 probability) was 4.2 with a 95% confidence interval that ranged from 3.9 ΔE* units to 4.7 ΔE* units. CONCLUSIONS Within the limitation of this study, the following conclusions were made: 1. The mean color perceptibility threshold was significantly lower than the mean color acceptability threshold. 2. Significant differences between different observers groups were noticed in determination of perceptibility and acceptability of color differences. The technicians groups displayed lower perceptibility and acceptability limits than the dental nurses and non-dental observers. CLINICAL SIGNIFICANCE When shade matching artificial denture teeth to natural teeth, 50:50 perceptibility (1.9 ΔE* units) and acceptability (4.2 ΔE* units) thresholds are used to compare color difference values. The technicians group displayed lower perceptibility and acceptability limits than other observers.

Prevalence and Risk Indicators of Erosion in Thirteen- to Fourteen-Year-Olds on the Isle of Man

Aims: The aim was to determine the prevalence of erosion in 13- to 14-year-old children on the Isle of Man and to investigate the strength of association with dietary risk factors. Methods: Exposed dentine was assessed on smooth surfaces of incisors/canines and occlusal surfaces of first molars. A questionnaire assessed the consumption frequency of foodstuffs. Results: Of 629 children examined, 124 (20%) had dentine exposed labially, palatally or occlusally. More males had dentine exposed on these surfaces (OR = 1.7, 95% CI = 1.2–2.6). Palatal dentine exposure was present in 3% of the children and occlusal dentine exposure in 18%. In bivariate analyses, drinking fizzy drinks more than once a day was associated with erosion (OR = 1.6, 95% CI = 1.1–2.3). The mean DMFT scores were not statistically different for the children with smooth surface/occlusally exposed dentine (1.37) compared to those without (1.58). Multiple regression analysis showed age, gender and toothbrushing to be significant predictors of erosion. Conclusion: This study has found a higher proportion of 13- to 14-year-old children with exposed dentine in molars than previous studies. The results corroborate previous reports that males have more erosion than females.

Facets of job satisfaction of dental practitioners working in different organisational settings in England

Introduction Before April 2006, English dentists were either working as an NHS general dental service (GDS) practitioner (fee-per-item, no local contractual obligations); an NHS personal dental service (PDS) practitioner (block contract with the primary care trust (PCT)); a private practitioner (either fee-per-item or capitation-based, independent of the PCT); or in a situation where they were mixing their NHS work (either under the GDS or PDS arrangements) with private work.Objectives To a) investigate the extent of the mix of NHS and private work in English dentists working in the GDS and PDS, b) to compare global job satisfaction, and c) to compare facets of job satisfaction for practitioners working in the different organisational settings of PDS practices, GDS practices and practices where there is a mix of NHS and private provision.Method A questionnaire was sent to 684 practitioners, containing 83 attitudinal statements relating to job facets, a global job satisfaction score and questions concerning workload.Results Response rate was 65.2%. More PDS than GDS dentists were found to treat the majority of their patients under the NHS. GDS dentists working fully in the NHS were least likely to be satisfied with their job, followed by PDS practitioners and then GDS dentists working in mixed NHS/private practices. Private practitioners were the most satisfied.Conclusion Differences between GDS, PDS and private practitioners were found in global job satisfaction and in the facets of job satisfaction related to restriction in being able to provide quality care, control of work and developing clinical skills.

Caries Prevalence Four Years after the End of a Randomised Controlled Trial

This study measured dental caries in children after cessation of a 30-month randomised clinical trial in which the intervention group received supervised toothbrushing once a day at school with 1,000 ppm fluoride toothpaste and a home support package encouraging twice-daily toothbrushing. The non-intervention group did not brush at school or receive the home support package. Children were aged 5 years at baseline and were examined every 6 months during the trial, then at 6, 18, 30 and 54 months after the end of the trial. Significantly less caries developed in first permanent molars of intervention children at the end of the trial. Of the 428 children who were examined at the end of the trial 329 (77%) were examined 54 months later when the children were aged 12 years on average. The intervention group still had less caries (D3FS caries increment 1.62) than the non-intervention children (D3FS caries increment 2.65, p < 0.05). Prolonged benefits have been found for intervention children principally in less caries in first permanent molars. Further follow-up at an age when the second molars and premolars have all erupted will help determine whether this benefit is due to a long-term behavioural change or a prolonged biological effect.

Analysis of health behaviour change interventions for preventing dental caries delivered in primary schools.

To improve oral health in children, the key behaviours (tooth brushing and sugar control) responsible for development of dental caries need to be better understood, as well as how to promote these behaviours effectively so they become habitual; and, the specific, optimal techniques to use in interventions. The aim of this paper is to describe and analyse the behaviour change techniques that have been used in primary school-based interventions to prevent dental caries (utilizing a Cochrane systematic review that we have undertaken) and to identify opportunities for improving future interventions by incorporating a comprehensive range of behaviour change techniques. Papers of five interventions were reviewed and data were independently extracted. Results indicate that behaviour change techniques were limited to information-behaviour links, information on consequences, instruction and demonstration of behaviours. None of the interventions were based on behaviour change theory. We conclude that behaviour change techniques used in school interventions to reduce dental caries were limited and focused around providing information about how behaviour impacts on health and the consequences of not developing the correct health behaviours as well as providing oral hygiene instruction. Establishing which techniques are effective is difficult due to poor reporting of interventions in studies. Future design of oral health promotion interventions using behaviour change theory for development and evaluation (and reporting results in academic journals) could strengthen the potential for efficacy and provide a framework to use a much wider range of behaviour change techniques. Future studies should include development and publication of intervention manuals which is becoming standard practice in other health promoting programmes.

The survival of direct composite restorations in the management of severe tooth wear including attrition and erosion: A prospective 8-year study

OBJECTIVES Survival of directly placed composite to restore worn teeth has been reported in studies with small sample sizes, short observation periods and different materials. This study aimed to estimate survival for a hybrid composite placed by one clinician up to 8-years follow-up. METHODS All patients were referred and recruited for a prospective observational cohort study. One composite was used: Spectrum(®) (DentsplyDeTrey). Most restorations were placed on the maxillary anterior teeth using a Dahl approach. RESULTS A total of 1010 direct composites were placed in 164 patients. Mean follow-up time was 33.8 months (s.d. 27.7). 71 of 1010 restorations failed during follow-up. The estimated failure rate in the first year was 5.4% (95% CI 3.7-7.0%). Time to failure was significantly greater in older subjects (p=0.005) and when a lack of posterior support was present (p=0.003). Bruxism and an increase in the occlusal vertical dimension were not associated with failure. The proportion of failures was greater in patients with a Class 3 or edge-to-edge incisal relationship than in Class 1 and Class 2 cases but this was not statistically significant. More failures occurred in the lower arch (9.6%) compared to the upper arch (6%) with the largest number of composites having been placed on the maxillary incisors (n=519). CONCLUSION The worn dentition presents a restorative challenge but composite is an appropriate restorative material. CLINICAL SIGNIFICANCE This study shows that posterior occlusal support is necessary to optimise survival.