Concordance Between Clinical Practice and Published Evidence: Findings From Virginia Commonwealth University School of Dentistry.

OBJECTIVES: To evaluate the concordance between clinical practice and published evidence by dental faculty and graduating students of the Virginia Commonwealth University School of Dentistry. METHODS: A questionnaire previously developed by the National Dental Practice-Based Research Network with 12 clinical scenarios was administered to VCU faculty and graduating students. Responses were scored as either consistent or inconsistent with published evidence and then analyzed for differences between dental faculty, graduating students, and the national results. RESULTS: There were 43 dental faculty members with at least half-time student contact who responded to the survey. Faculty concordance ranged from 33% to 100%, and general practice faculty had the highest concordance (82%). Eighty-five of the graduating class of 98 responded to the survey, and student concordance ranged from 18% to 92% and averaged 67%. General practice faculty had higher concordance with published evidence than recently graduated dental students. CONCLUSIONS: Graduating students and dental faculty demonstrated higher concordance with evidence-based practice than practitioners in the National Dental Practice-Based Research Network. General practice dental faculty demonstrated adequate concordance, but students demonstrated only a medium-level concordance. Practitioners involved in teaching dental students are better able to keep up with evolving evidence and are better able to demonstrate evidence-based practice.

An automated dental caries detection and scoring system for optical images of tooth occlusal surface.

Dental caries are one of the most prevalent chronic diseases. The management of dental caries demands detection of carious lesions at early stages. This study aims to design an automated system to detect and score caries lesions based on optical images of the occlusal tooth surface according to the International Caries Detection and Assessment System (ICDAS) guidelines. The system detects the tooth boundaries and irregular regions, and extracts 77 features from each image. These features include statistical measures of color space, grayscale image, as well as Wavelet Transform and Fourier Transform based features. Used in this study were 88 occlusal surface photographs of extracted teeth examined and scored by ICDAS experts. Seven ICDAS codes which show the different stages in caries development were collapsed into three classes: score 0, scores 1 and 2, and scores 3 to 6. The system shows accuracy of 86.3%, specificity of 91.7%, and sensitivity of 83.0% in ten-fold cross validation in classification of the tooth images. While the system needs further improvement and validation using larger datasets, it presents promising potential for clinical diagnostics with high accuracy and minimal cost. This is a notable advantage over existing systems requiring expensive imaging and external hardware.

Prediction of clinical outcomes of a restoration based on in vivo marginal quality evaluation.

The question "Does initial marginal quality of composite restorations have any affect on clinical longevity?" is posed and evidence presented to attempt to provide an answer. This paper examines the literature on what is known regarding the rates and causes of failure of restorations, clinical evaluation of restoration outcomes and marginal quality, the relationship between marginal quality and secondary caries, and the relationship of polymerization shrinkage and clinical failures. The most frequently reported cause for restoration replacement is secondary caries. The evidence that poor marginal quality promotes or is the primary cause for secondary caries is limited and indicates that any direct relationship is unlikely. There is evidence that secondary caries is related to the bacterial composition of marginal plaque, and that this and oral hygiene are the primary factors in disease initiation. Evidence also exists that dentists vary in their diagnoses of secondary caries and that except in the presence of frank secondary caries, it is not possible to diagnose secondary caries with high sensitivity and specificity based on visual and tactile examination of restoration margins. Marginal gaps created by polymerization shrinkage do not appear to increase the risk for secondary caries, but can lead to marginal staining. Initial marginal quality should not affect longevity, as it does not necessarily increase the risk of secondary caries. However, poor marginal quality is, in fact, likely to decrease clinical longevity due to the misdiagnosis of secondary caries.

Clinical performance evaluation of a packable posterior composite in bulk-cured restorations.

BACKGROUND: The authors evaluated the clinical performance of Prodigy Condensable (Kerr, Orange, Calif.) composite placed and cured in increments up to 5 millimeters thick. METHODS: The authors placed 57 Class II restorations in 32 patients in composite increments up to 5 mm thick. Using this technique, they placed the majority of restorations in one increment and then carved the occlusal and proximal anatomy before light curing. The authors evaluated the restorations at three, six, 12, 24 and 36 months. RESULTS: No restorations required replacement; however, 11 developed a defect requiring repair or continued observation. Of these 11, nine restorations developed defects on the margins of the restorations and two developed secondary caries. The Kaplan-Meier estimate of probability that a restoration would develop a defect during 36 months that would require immediate repair was 0.13. Postoperative sensitivity was not significantly different from preoperative sensitivity. CONCLUSIONS: The authors found that no restorations required replacement and no increased postoperative sensitivity occurred. CLINICAL IMPLICATIONS: The authors suggest that this composite material can be placed in a single increment up to 5 mm thick for Class II restorations.

Clinical challenges and the relevance of materials testing for posterior composite restorations.

Posterior composite restorations have been in use for approximately 30 years. The early experiences with this treatment indicated there were more clinical challenges and higher failure rates than amalgam restorations. Since the early days of posterior composites, many improvements in materials, techniques, and instruments for placing these restorations have occurred. This paper reviews what is known regarding current clinical challenges with posterior composite restorations and reviews the primary method for collecting clinical performance data. This review categorizes the challenges as those related to the restorative materials, those related to the dentist, and those related to the patient. The clinical relevance of laboratory tests is discussed from the perspective of solving the remaining clinical challenges of current materials and of screening new materials. The clinical problems related to early composite materials are no longer serious clinical challenges. Clinical data indicate that secondary caries and restoration fracture are the most common clinical problems and merit further investigation. The effect of the dentist and patient on performance of posterior composite restorations is unclear and more clinical data from hypothesis-driven clinical trials are needed to understand these factors. Improvements in handling properties to ensure void-free placement and complete cure should be investigated to improve clinical outcomes. There is a general lack of data that correlates clinical performance with laboratory materials testing. A proposed list of materials tests that may predict performance in a variety of clinical factors is presented. Polymerization shrinkage and the problems that have been attributed to this property of composite are reviewed. There is a lack of evidence that indicates polymerization shrinkage is the primary cause of secondary caries. It is recommended that composite materials be developed with antibacterial properties as a way of reducing failures due to secondary caries. Post-operative sensitivity appears to be more related to the dentin adhesives' ability to seal open dentinal tubules rather than the effects of polymerization shrinkage on cuspal deflections and marginal adaptation.

Tooth whitening today.

BACKGROUND: Methods to improve the esthetics of the dentition by tooth whitening are of interest to dentists, their patients and the public. In the past 20 years, research on bleaching and other methods of removing tooth discolorations has dramatically increased. Dentist-supervised and over-the-counter products now are available to solve a variety of tooth discoloration problems without restorative intervention. The indications for appropriate use of tooth-whitening methods and products are dependent on correct diagnosis of the discoloration. OVERVIEW: Tooth-whitening methods include the use of peroxide bleaching agents to remove internal discolorations or abrasive products to remove external stains. Peroxide bleaching procedures are completed by the dentist in single or multiple appointments, or by the patient over a period of weeks to months using custom trays loaded with a bleaching agent. Both methods are safe and effective when supervised by the dentist. Microabrasion is indicated for the removal of isolated discolorations that often are associated with fluorosis. Whitening toothpastes remove surface stains only through the polishing effect of the abrasives they contain. CONCLUSIONS AND PRACTICE IMPLICATIONS: Tooth whitening is a form of dental treatment and should be completed as part of a comprehensive treatment plan developed by a dentist after an oral examination. When used appropriately, tooth-whitening methods are safe and effective.