Abstract
Introduction: Microleakage is a major concern in composite restorations, especially with margins located on dentin or cementum of the tooth. This study aimed to review the available literature investigating in vitro the efficacy of different tooth lining materials on the marginal seal of composite restorations extended below the Cemento-Enamel Junction (CEJ) of the tooth.
Materials and Methods: Different combinations of the review terms were used to electronically search PubMed, Google Scholar, Cochrane Library, and Ebscohost databases for the last fifteen years. The records were initially screened for relevancy based on title and abstract. Articles that seemed to meet the criteria for inclusion were selected for full-text assessment. Studies deemed eligible were in vitro studies conducted on human teeth with cavities extending below the CEJ and restored using different tooth lining materials under the composite restorations.Every included study was evaluated using the Cochrane risk of bias assessment tool.
Results: The initial search identified 619 publications. After removing duplicated records, the remaining 421 records are screened at the level of titles and abstracts to meet our inclusion criteria. 62 records were designated for full-text methodological assessment, and 15 studies were found eligible for qualitative synthesis. The sealing ability of different tooth lining materials under composite restorations was investigated in the chosen studies, with varying outcomes. Microleakage in the tooth restorations was determined by examining the extent of dye penetration under a microscope.
Conclusion: Despite the reports of less dye penetration with specific tooth liners in some in-vitro studies, there is no consistent evidence supporting that such tooth liners could reduce microleakage in composite restorations of the tooth.