RESUMEN
Posterior adhesive restorations are a basic procedure in general dental practices, but their application remains poorly standardized as a result of the number of available options. An abundant number of study hypotheses corresponding to almost unlimited combinations of preparation techniques, adhesive procedures, restorative options, and materials have been described in the literature and submitted to various evaluation protocols. A literature review was thus conducted on adhesive Class I and II restorations and nondestructive in vitro tests using the PubMed/Medline database for the 1995-2010 period. The first part of this review discusses the selected literature related to photoelasticity, finite element analysis (FEM), and microleakage protocols. Based on the aforementioned evaluation methods, the following parameters proved influential: cavity dimensions and design, activation mode (light or chemical), type of curing light, layering technique, and composite structure or physical characteristics. Photoelasticity has various limitations and has been largely (and advantageously) replaced by the FEM technique. The results of microleakage studies proved to be highly inconsistent, and the further use of this technique should be strictly limited. Other study protocols for adhesive Class II restorations were also reviewed and will be addressed in part II of this article, together with a tentative relevance hierarchy of selected in vitro methods.
Asunto(s)
Resinas Compuestas/uso terapéutico , Restauración Dental Permanente/métodos , Resinas Compuestas/normas , Cementos Dentales/uso terapéutico , Fracaso de la Restauración Dental , Restauración Dental Permanente/normas , Análisis del Estrés Dental , Humanos , Técnicas In VitroRESUMEN
A literature review was conducted on adhesive Class I and II restorations and nondestructive in vitro tests using the PubMed/Medline database for the 1995-2010 period. The first part of this review has presented and critically appraised selected literature dealing with the quality and in vitro behavior of adhesive Class II restorations using photoelasticity, finite element analysis, and microleakage study protocols. This second part reviews additional parameters, which are deformation and fracture resistance to cyclic loading, shrinkage stress and tooth deformation following restoration placement, bond strength (microtensile, tensile, and shear tests), and marginal and internal adaptation. In addition, a "relevance score" has been proposed that aims to classify the different study protocols according, firstly, to the resulting quality, quantity, and consistency of the evidence and then, secondly, to their potential clinical relevance, as estimated by their ability to simulate oral and biomechanical strains. The highest clinical relevance was attributed to marginal and internal adaptation studies, following cyclic loading in a moist environement. However, a combination of in vitro protocols will have an even greater predictive potential and has to be considered as a crucial preclinical research approach with which to investigate the numerous restorative configurations that cannot be efficiently and rapidly tested in vivo.