Richard S Callan

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Historically, postoperative pain associated with temperature was considered a thermal conduction problem. More recently, pulpal hydrodynamics has been used to explain this sensitivity. Relative to restorations placed with dentin bonding agents that require a separate etching step, agents that include an acidic primer are believed to result in a better seal(More)
PURPOSE To evaluate two commercially available doctor-supplied, patient-applied, bleaching systems for their ability to whiten the maxillary anterior teeth while at the same time not causing sensitivity. METHODS 46 participants were randomly assigned to one of two groups: One group received Rembrandt Xtra-Comfort and the other group Nite White Excel 2Z.(More)
OBJECTIVE The purpose of this study was to examine the effect of solvent concentration on the degree of conversion of a model photo-activated resin formulation when placed as a thin film in ambient air. METHODS A photo-activated co-monomer mixture (ethoxylated bis-GMA/TEGDMA) (Bisco Inc.) was diluted into six concentrations (from 1.0 to 13.0M) with either(More)
The purpose of this study was to explore perceptions of the roles and responsibilities of dental education in serving the public good, and the extent to which they are being met, from the vantage point of leaders at the university and state level. Five questions were developed to gather views on dental education's success in meeting the expectations and(More)
As teaching institutions, it is vital for dental schools to collect data on accidental injuries to identify potential problems, improve the quality of care of patients, and educate future practitioners about risk management. Our data reveal important trends concerning such injuries. These data were compiled over a two-year period (2001-03) from accident(More)
In order to use CAD CAM (Computer Aided Design, Computer Aided Manufacturing) technology as an assessment tool when evaluating the preclinical performance of dental students, it is imperative that one has confidence in the reliability of the process. In this study, a variety of alignment methods were compared to determine both the consistency and accuracy(More)
Technological changes to blue light-emitting diode (LED) light-curing units have taken place at an accelerated rate. The lighting industry, however, has not yet improved output levels of blue chip design used in dental LED units as quickly. In fact, the same 5 watt source has been offered since 1992. The next step in technology advancement is the use of(More)
Recent efforts have been directed towards utilizing CAD/CAM technology in the education of future dentists. The purpose of this pilot study was to investigate the feasibility of implementing CAD/CAM technology in instruction on preparing a tooth for restoration. Students at one dental school were assigned access to CAD/CAM technology vs. traditional(More)
Original large-particle composites exhibited poor wear characteristics. With the packable composites, there has been a reintroduction of large particles. The clinical wear characteristics of such packable composites are relatively unknown. The purpose of this study was to compare wear between two types of packable composites: Alert (Jeneric Pentron) and(More)
OBJECTIVES Transient sensitivity during bleaching is generally reported to affect 67% of patients. While most people tolerate this sensitivity, some find it impossible to continue treatment. The purpose of this study was to determine the safety and efficacy of an experimental, low-sensitivity bleaching agent. METHOD AND MATERIALS Twenty-two participants(More)