Clinical effectiveness of contemporary adhesives: a systematic review of current clinical trials.

OBJECTIVES The purpose of this paper was to review current literature on the clinical effectiveness of contemporary adhesives when used to restore cervical non-carious class-V lesions. Restoration retention in function of time was recorded in order to find out if adhesives with a simplified application procedure are as clinically effective as conventional three-step adhesives. DATA SOURCES Literature published from January 1998 up to May 2004 was reviewed for university-centred clinical trials that tested the clinical effectiveness of adhesives in non-carious class-V lesions. Restoration-retention rates per adhesive reported in peer-reviewed papers as well as IADR-AADR abstracts and ConsEuro abstracts were included and depicted as a function of time in graphs for each of the five adhesive classes (three- and two-step etch-and-rinse adhesives, two- and one-step self-etch adhesives, and glass-ionomers). The guidelines for dentin and enamel adhesive materials advanced by the American Dental Association were used as a reference. Per class, the annual failure rate (%) was calculated. Kruskal-Wallis analysis and Dwass-Steel-Chritchlow-Fligner pairwise comparisons were used to determine statistical differences between the annual failure percentages of the five adhesive categories. RESULTS Comparison of retention of class-V adhesive restorations as a measure to determine clinical bonding effectiveness of adhesives revealed that glass-ionomers most effectively and durably bond to tooth tissue. Three-step etch-and-rinse adhesives and two-step self-etch adhesives showed a clinically reliable and predictably good clinical performance. The clinical effectiveness of two-step etch-and-rinse adhesives was less favourable, while an inefficient clinical performance was noted for the one-step self-etch adhesives. SIGNIFICANCE Although there is a tendency towards adhesives with simplified application procedures, simplification so far appears to induce loss of effectiveness. Clinical performance can be correlated with, and predicted by, appropriate types of laboratory study.