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Introduction: Although the maxillary first molar (MFM) has been frequently subjected to stress analysis in endodontic investigations, the available data about the effect of its oblique ridge are quite sparse. The aim of this study includes evaluating the effect of the residual oblique ridge on the stress distribution after preparing conservative access cavities., Methods: Based on the cone-beam computed tomographic data, the model of an intact MFM and 5 cavity designs were prepared for endodontic treatment, which were consequently filled with gutta-percha and dental resin composite (6 total models). All models were subjected to 4 types of occlusal loading; finite element analysis via ABAQUS CAE software (Dassault Systemes, Vélizy-Villacoublay, France) was accomplished, whereas other software programs such as (Mimics Research Materialise, Leuven, Belgium) and 3-Matic Research (Materialise) were also incorporated in different stages for detecting stress distribution., Results: The stress distribution on the MFM is not only dependent on the remaining width of the oblique ridge but also on the type of loading. The most stress on the cervical region was concentrated on the palatal root in some type of loading, whereas the least stress on the occlusal surface was recorded when the whole oblique ridge was replaced by the composite resin., Conclusions: When the occlusal contacts are occurring only on the palatal cusp, the stress distribution on the oblique ridge is noticeably affected by the cavity design., (Copyright © 2020 American Association of Endodontists. Published by Elsevier Inc. All rights reserved.)

One often alleges that laboratory bond-strength testing cannot predict clinical effectiveness of adhesives. Major argument to sustain this claim is the wide variation in bond-strength values recorded for one specific adhesive among different research institutes worldwide. The main reason for these inconsistent bond-strength measurements is supposedly the current lack of a standard bond-strength testing protocol. This paper (and presentation) aimed to report on an extensive literature review with regard to the different laboratory bond-strength test methods and their data provided, along with a second extensive literature review on clinical effectiveness data of adhesives in terms of retention rates of adhesive Class-V restorations. Combining both systematic reviews, we have subsequently searched for a potential relationship between bond-strength data and clinical outcomes., (Copyright 2009 Academy of Dental Materials. Published by Elsevier Ltd. All rights reserved.)