Prediction and diagnosis of clinical outcomes affecting restoration margins

Abstract

The longevity of dental restorations is largely dependent on the continuity at the interface between the restorative material and adjacent tooth structure (the restoration margin). Clinical decisions on restoration repair or replacement are usually based upon the weakest point along that margin interface. Physical properties of a restorative material, such as polymerisation shrinkage, water sorption, solubility, elastic modulus and shear strength, all have an effect on stress distribution and can significantly affect margin integrity. This review will focus on two aspects of margin deterioration in the oral environment: the in vitro testing of margin seal using emersion techniques to simulate the oral environment and to predict clinical margin failure and the relationship between clinically observable microleakage and secondary caries. The many variables associated with in vitro testing of marginal leakage and the interpretation of the data are presented in detail. The most recent studies of marginal leakage mirror earlier methodology and lack validity and reliability. The lack of standardised testing procedures makes it impossible to compare studies or to predict the clinical performance of adhesive materials. Continual repeated in vitro studies contribute little to the science in this area. Clinical evidence is cited to refute earlier conclusions that clinical microleakage (penetrating margin discoloration) leads to caries development and is an indication for restoration replacement. Margin defects, without visible evidence of soft dentin on the wall or base of the defect, should be monitored, repaired or resealed, in lieu of total restoration replacement.

Influence of fluoride-containing adhesives and bleaching agents on enamel bond strength

“…Marginal gaps in the restoration frequently lead to post-operative sensibility, marginal staining, and the development of pulp pathologies as a consequence of secondary carious lesions. 1 The development of secondary caries is similar to that of primary caries but differs according to the location and characteristics of the surface, such as roughness and marginal defects. 2,3 Conventional three-and two-step etch-and-rinse adhesives can effectively seal the enamel interface.…”

Secondary caries and microleakage

“…Despite appeals from journal editors and some researchers to advance the methodology of microleakage experiments, rather than reporting more data, relatively few papers describe the effects of experimental variables on the outcomes [4][5][6][7][8][9][10]. As a consequence, there are great variations in experimental setups [116][117], to the extent that it is seldom possibility to meta-analyse any results [115].…”

“…As a consequence, there are great variations in experimental setups [116][117], to the extent that it is seldom possibility to meta-analyse any results [115]. Besides the still unknown confounders, numerous variables influence the microleakage experiment outcomes [7][8][9][10]. Examples are the source and type of teeth or tooth specimens, and choice of storage substrate and -time.…”

“…It is also poor versus reported incidences of secondary caries observed in clinical efficacy or effectiveness studies [4][5][6][7][8][9][10]. There are probably multiple reasons for the incongruence between experimental data and clinical observations of secondary caries.…”

Evaluation of the Surface Roughness and Microleakage of Dental Composites Exposed to Different Beverages

“…8 There was always great interest in the fit of restorative materials to the walls of cavities and in the retentive ability of the material to seal the cavity against the penetration of microorganisms and saliva. 9 Microleakage in restorative materials is a big problem in clinical dentistry. 10 Composite may exhibit reduced properties along time, which increases it susceptibility to wear and marginal microleakage when in contact with liquids.…”