Oral hygiene and infective endocarditis: a case control study.

OBJECTIVE: To determine if oral hygiene is associated with infective endocarditis (IE) among those at moderate risk for IE. STUDY DESIGN: This is a case control study of oral hygiene among hospitalized patients with IE (cases) and outpatients with heart valve disease but without IE (controls). The primary outcome was the mean dental calculus index. Secondary outcomes included other measures of oral hygiene and periodontal disease (e.g., dental plaque, gingivitis) and categorization of blood culture bacterial species in case participants. RESULTS: The 62 case participants had 53% greater mean dental calculus index than the 119 control participants (0.84, 0.55, respectively; difference = 0.29, 95% CI: 0.11, 0.48; P = .002) and 26% greater mean dental plaque index (0.88, 0.70, respectively; difference = 0.18, 95% CI: 0.01.0.36; P = .043). Overall, cases reported fewer dentist and dental hygiene visits (P = .013) and fewer dental visits in the 12 weeks before enrollment than controls (P = .007). Common oral bacteria were identified from blood cultures in 27 of 62 cases (44%). CONCLUSIONS: These data provide evidence to support and strengthen current American Heart Association guidance that those at risk for IE can reduce potential sources of IE-related bacteremia by maintaining optimal oral health through regular professional dental care and oral hygiene procedures.

Conference summary: Navigating the Sea of Genomic Data, October 28-29, 2015.

BACKGROUND: The rapid pace of biomedical discoveries in the past few years has resulted in substantial advances in our ability to diagnose, treat, and prevent a wide variety of diseases. The sequencing of the human genome offered the possibility of understanding the etiology, pathogenesis, and risk of developing disease from a genetic perspective and has resulted, for example, in the development of genomic-based diagnostic or risk-assessment tests for a number of medical and dental conditions. To assess the scientific evidence underlying such tests and determine whether they may be useful in clinical practice, practitioners need to have a basic understanding of the state-of-the-science of genomics and genetic testing. OBJECTIVE: To assist practitioners in understanding the science of genomics, the American Dental Association and the Task Force on Design and Analysis in Oral Health Research co-sponsored a landmark conference, Navigating the Sea of Genomic Data, held October 28-29, 2015, at the American Dental Association headquarters building in Chicago, IL. The purpose of this conference was to review the basics of genomic science, promote sound design and analysis of genomic studies of oral diseases, and provide a basis or "framework" to guide practitioners in assessing new development in genomics and genetic tests for oral diseases. OVERVIEW: Presentations at this conference were made by 9 world-renowned scientists who discussed a wide range of topics involving genomic science, genetic testing for rare mendelian single gene disorders, and genetic testing for assessing the risk of experiencing common complex diseases. This article summarizes the key points and concepts presented by the speakers. PRACTICAL IMPLICATIONS: It is essential for oral health care professionals to have a fundamental understanding of genomic science so that they can evaluate new advances in this field and the use of genetic testing for the benefit of their patients.

Understanding and evaluating meta-analysis.

BACKGROUND: Meta-analysis refers to statistical methodology used to combine data from many studies to obtain an overall assessment of disease risk or treatment outcomes. In this article, the authors review basic methods, interpretation, and limitations of meta-analysis. METHODS: Investigators use meta-analysis approaches to combine data from available studies to obtain an answer to a specific question. An investigator uses a fixed model if there is homogeneity among the combined studies and a random-effects model if there is heterogeneity. The random-effects model results in wider confidence limits and more conservative estimates of overall results. A meta-analysis can be biased because studies with negative results (no differences in treatment outcomes) are less likely to be published (publication bias). RESULTS: A meta-analysis should include a well-specified and reproducible set of procedures, including description of data abstraction procedures, attempts to include unpublished studies, and appropriate statistical analysis that includes thorough consideration of heterogeneity and potential bias. CONCLUSIONS: Meta-analysis cannot correct shortcomings of existing studies or data. However, if potential pitfalls are recognized, meta-analysis can be a useful tool for summarizing existing studies, providing a means to address conflicting reports. Meta-analysis can lead to increased precision, providing greater power to detect existing relationships or treatment effects. Furthermore, meta-analysis may make it possible to address questions that cannot be answered by means of individual studies. PRACTICAL IMPLICATIONS: Meta-analysis provides an objective, quantitative synthesis of available studies but needs to be understood and assessed critically by those who use it to assess risk or make treatment decisions.

Is change in probing depth a reliable predictor of change in clinical attachment loss?

BACKGROUND: Clinicians and researchers need a measure for monitoring the periodontal condition of their patients or study participants. The authors explored the utility of change in probing depth (PD) for predicting change in clinical attachment loss (CAL). METHODS: The authors used clinical trial data from 363 participants who had received nonsurgical treatment to describe associations between PD and CAL changes. They computed the association between PD and CAL changes-correlation, sensitivity, specificity, and positive and negative predictive values-according to tooth type, tooth site and initial PD. RESULTS: Depending on the subset of tooth sites, sensitivity of PD change to predict CAL change ranged from 18 to 74 percent; the highest sensitivity was at initially deep sites. Specificity and negative predictive value were higher than sensitivity and positive predictive value. Correlations between person-level mean PD and CAL changes ranged from 0.60 to 0.79 and were highest at initially deep sites. CONCLUSIONS: Except at initially deep sites, PD change did not reliably predict CAL change. Clinicians and researchers who measure only PD may fail to identify teeth that lose or gain attachment. CLINICAL IMPLICATIONS: Clinicians should consider monitoring CAL to detect changes in periodontal status more reliably. It is unknown if these findings apply to patients treated surgically or to prediction of tooth loss.

A practitioner's guide to developing critical appraisal skills: interventional studies.

BACKGROUND AND OVERVIEW: Randomized controlled clinical trials are considered to provide the highest level of evidence for clinical practice, public health policy and evidence-based systematic reviews. Although all randomized controlled clinical trials share basic design characteristics, to assess the outcome of a particular trial one must carefully evaluate specific details of its design and analysis that might bias the study and influence its results. In this article, the authors review key points that practitioners should consider when assessing randomized controlled clinical trials so they can determine the applicability of study results to clinical practice. CONCLUSIONS AND PRACTICE IMPLICATIONS: Dentists encounter a variety of types of evidence when trying to assess the utility of new therapeutic agents and procedures for their clinical practice. This article provides a background to use in evaluating data and selecting studies that provide the most rigorous clinical support for safety and effectiveness.

Randomized controlled trials: what are they and who needs them?

Dentistry is rapidly entering a new era of evidence-based practice, and society is demanding prevention and treatment that has been proven to be effective in terms of meaningful health outcomes. Practitioners, individual patients and the public need randomized controlled trials because they provide the highest level of scientific evidence to change clinical practice and inform public health policy. Well-designed randomized controlled trials are conceptually simple but deceptively complex to design, implement and translate into clinical practice. Randomized controlled trials are fundamentally different from observational clinical research because they randomly assign volunteers to receive test or control interventions, they are prospective and the success of the test intervention is based on a meaningful clinical outcome that is specified before the trial begins. To be successful, randomized controlled trials must be carefully designed and powered to answer a specific question that will be generalizable to the population under study. Randomized controlled trials can be designed to evaluate efficacy, effectiveness, superiority, equivalence or noninferiority. Prominent issues and challenges in designing and conducting randomized controlled trials include carefully defining enrollment criteria, establishing an organizational infrastructure, use of a data-coordinating center, developing a manual of procedures, obtaining informed consent, recruiting and ensuring the safety of volunteer subjects, ensuring data quality, analysis and publication of trial outcomes, and translating results into clinical practice.

A practitioner's guide to developing critical appraisal skills: the fundamentals of research.

BACKGROUND AND OVERVIEW: This is the first of a series of articles summarizing the basic principles and methods of research with an emphasis on clinical investigation. In today's environment of evidence-based practice, the prevention of, diagnosis of, prognosis for and treatment of oral diseases must be based on a critical evaluation of available research. The purpose of this series is to help practitioners understand research and develop skills in interpreting research published in the medical and dental literature. CONCLUSIONS AND PRACTICE IMPLICATIONS: Research involves systematic investigation and can be categorized in different ways. Primary research may take several forms and includes basic and applied research. Basic research seeks fundamental knowledge without having a specific application; applied research is conducted for the purpose of a specific application and often is predicated on basic research findings. Applied research may take several forms and includes clinical research, which seeks to inform patients, clinicians, public health workers and policymakers about methods of preventing and treating diseases. Secondary research involves the use of existing data and results of published scientific studies. Systematic literature reviews are a form of secondary research that attempt to remove bias often associated with narrative reviews.