The scientific evidence for pre-adjusted edgewise attachments and mechanics.

Introduction Fixed orthodontic appliance systems continue to evolve with a wealth of evidence emerging to underpin these refinements.Aims To present the evidence from comparative prospective research informing the selection of fixed appliance design and mechanics.Design Detailed literature review.Materials and methods An electronic search to identify randomised controlled trials and clinical controlled trials was undertaken using pre-defined search terms.Results Based on high-level evidence, no one bracket system has been proven superior in terms of efficiency or outcome. Similarly, a clear advantage associated with one wire type or dimension has not been shown. The effect of lacebacks in terms of anchorage management appears to be limited, while elastomeric chain and nickel titanium closing coils are associated with similar rates of space closure.Discussion A wealth of high-quality recent evidence to support the selection of fixed appliance attachments, archwires and auxiliaries, including lacebacks and space closing mechanics, was identified.Conclusions There has been a considerable increase in the amount of high-quality evidence informing the choice of pre-adjusted edgewise mechanics in recent years. This information can be used to make evidence-based decisions in the selection and manipulation of fixed appliances during daily practice.

Planning the Future Oral Health Workforce: A Rapid Review of Supply, Demand and Need Models, Data Sources and Skill Mix Considerations.

Over the last decade, there has been a renewed interest in oral health workforce planning. The purpose of this review is to examine oral health workforce planning models on supply, demand and needs, mainly in respect to their data sources, modelling technique and use of skill mix. A limited search was carried out on PubMed and Web of Science for published scientific articles on oral health workforce planning models between 2010 to 2020. No restrictions were placed on the type of modelling philosophy, and all studies including supply, demand or needs based models were included. Rapid review methods guided the review process. Twenty-three studies from 15 countries were included in the review. A majority were from high-income countries (n = 17). Dentists were the sole oral health workforce group modelled in 13 studies; only five studies included skill mix (allied dental personnel) considerations. The most common application of modelling was a workforce to population ratio or a needs-based demand weighted variant. Nearly all studies presented weaknesses in modelling process due to the limitations in data sources and/or non-availability of the necessary data to inform oral health workforce planning. Skill mix considerations in planning models were also limited to horizontal integration within oral health professionals. Planning for the future oral health workforce is heavily reliant on quality data being available for supply, demand and needs models. Integrated methodologies that expand skill mix considerations and account for uncertainty are essential for future planning exercises.

Level of fellowship training increases adenoma detection rates.

BACKGROUND & AIMS: The adenoma detection rate (ADR) is critical to the success of colonoscopy for colorectal cancer screening. The effects of involving gastroenterology fellows in screening colonoscopies are uncertain. We assessed the effects of gastroenterology fellow participation on ADR and whether outcomes vary with year of fellowship training. METHODS: We performed a retrospective review of all average-risk screening colonoscopies performed from April 2005-April 2007 at the University of Colorado Hospital. A gastroenterology attending physician alone performed 2895 colonoscopies; 699 were performed by a gastroenterology fellow supervised by an attending physician. Statistical analyses of polyp, adenoma, and advanced adenoma (or cancer) detection were performed by using logistic regression. RESULTS: The ADR was significantly higher (odds ratio [OR], 1.32; 95% confidence interval [CI], 1.10-1.59) among colonoscopies that included a gastroenterology fellow compared with those performed by only a gastroenterology attending physician. Similarly, the polyp detection rate was higher (OR, 1.28; 95% CI, 1.08-1.52) among colonoscopies involving a gastroenterology fellow. There was no difference in the detection of advanced adenomas or cancers (OR, 1.05; 95% CI, 0.77-1.44) among colonoscopies involving a gastroenterology fellow. The ADR differed greatly by year of training. Compared with colonoscopies performed by an attending gastroenterologist alone, the ADR increased with each year of training: OR, 0.89 (95% CI, 0.66-1.22) for first-year fellows; OR, 1.31 (95% CI, 0.89-1.93) for second-year fellows; and OR, 1.70 (95% CI, 1.33-2.17) for third-year fellows. CONCLUSIONS: Involvement of fellows in screening colonoscopies increases the ADR, primarily because of the increased ADR in procedures involving third-year gastroenterology fellows.

Substance abuse and conscious sedation: theoretical and practical considerations.

Substance abuse is an issue that has been widely recognised both in the medical and dental professions. Many different recreational drugs exist and their use can have important consequences in relation to conscious sedation. As the use of illicit drugs is growing, it is important to have an understanding of the impact of substance abuse on determining if a patient is a suitable candidate for conscious sedation. It is important to appreciate that while human studies in this area are limited, animal studies and observation of the reactions of substance abusers to sedative agents demonstrate a potential link between illicit drug use and conscious sedation through drug interaction. This paper aims to discuss the importance of understanding substance abuse, the potential effects such substances can have in relation to conscious sedation and appropriate management techniques for substance abusers in order to provide optimum safe care when undergoing conscious sedation techniques.

An Update of Gorlin-Goltz Syndrome.

Gorlin-Goltz syndrome encompasses a variety of clinical signs and symptoms including important oral manifestations which general dental practitioners should be aware of. In light of the risk of malignancy it is important to be aware of this syndrome and recognise the need for early referral for multidisciplinary management. This paper aims to discuss Gorlin-Goltz syndrome, the pathophysiology of the condition and address the wide range of clinical manifestations. The author will pay particular attention to the oral manifestations of the condition and the management of such anomalies.

Regulation of the CYP1A1 gene by 2,3,7,8-tetrachlorodibenzo-p-dioxin but not by beta-naphthoflavone or 3-methylcholanthrene is altered in hepatitis C virus replicon-expressing cells.

Exposure to hepatitis C virus (HCV) can lead to the development of cirrhosis and hepatocellular carcinoma. To examine the effects of long-term HCV infection on hepatic cytochrome P450 1A1 (CYP1A1) expression and function, we used a human hepatoma cell line expressing the HCV subgenomic replicon (Huh.8) to evaluate CYP1A1 induction by the aryl hydrocarbon receptor (AhR) ligand, 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD). In this study, we demonstrate that the induction of CYP1A1 expression in Huh.8 cells by TCDD but not by beta-naphthoflavone or 3-methylcholanthrene was significantly diminished. TCDD exposure of Huh.8 cells resulted in greater than 55% suppression of CYP1A1 transcription compared with the parent cell line Huh7, whereas protein levels and enzyme activities were further diminished. Suppression of CYP1A1 mRNA expression in TCDD-treated Huh.8 cells was partially reversed after pretreatment with the antioxidants N-acetylcysteine and nordihydroguaiaretic acid, suggesting a role for oxidative stress. Induced CYP1A1 message, protein, and enzyme activity were partially restored in an Huh7 cell line expressing the HCV replicon containing a deletion in the nonstructural protein NS5A. Furthermore, adenoviral expression of NS5A in Huh7 partially suppressed TCDD-induced CYP1A1 protein and enzyme activity, implicating this protein in the mechanism of suppression. These findings demonstrate that TCDD-mediated AhR signaling is impaired in hepatocytes in which HCV is present and that NS5A alone or in the presence of other nonstructural proteins of the subgenomic replicon is in part responsible.

Methane production during lactulose breath test is associated with gastrointestinal disease presentation.

It has recently been determined that there is an increased prevalence of bacterial overgrowth in IBS. Since there are two gases (hydrogen and methane) measured on lactulose breath testing, we evaluated whether the different gas patterns on lactulose breath testing coincide with diarrhea and constipation symptoms in IBS and IBD. Consecutive patients referred to the gastrointestinal motility program at Cedars-Sinai Medical Center for lactulose breath testing were given a questionnaire to evaluate their gastrointestinal symptoms. Symptoms were graded on a scale of 0-5. Upon completion of the breath test, the results were divided into normal, hydrogen only, hydrogen and methane, and methane only positive breath tests. A comparison of all subjects and IBS subjects was undertaken to evaluate diarrhea and constipation with regards to the presence or absence of methane. This was further contrasted to Crohn's and ulcerative colitis (UC) patients in the database. After exclusion criteria, 551 subjects from the database were available for comparison. Of the 551 subjects (P < 0.05, one-way ANOVA) and in a subgroup of 296 IBS subjects (P < 0.05, one-way ANOVA), there was a significant association between the severity of reported constipation and the presence of methane. The opposite was true for diarrhea (P < 0.001). If a breath test was methane positive, this was 100% associated with constipation predominant IBS. Furthermore, IBS had a greater prevalence of methane production than Crohn's or UC. In fact, methane was almost nonexistent in the predominantly diarrheal conditions of Crohn's and UC. In conclusion, a methane positive breath test is associated with constipation as a symptom.