Glass ionomer derivates have better retention rates in cervical restorations compared to self-etching adhesive...

MEDLINE search and search of abstracts of IADR/AADR and ConsEuro conferences published between January 1998 and May 2004 revealed 85 prospective clinical trials on the clinical effectiveness of 57 different adhesive systems (or restoratives) in Class V restorations; 35 of these trials were published in peer-reviewed journals and 50 as conference abstracts. No further selection was made.

All studies had to include information on the retention rates. Five types of adhesives were differentiated: 3 and 2 step etch-and-etch adhesives, 2 and 1 step self-etch adhesives, and glass ionomer derivates. No minimal or maximal exposure limit was set.

The main outcome was the annual retention loss in relation to one of the 5 adhesive systems used in non-carious Class V restorations. The observation period of the studies varied between 0.5 years and 6 years.

Restorations with glass ionomer derivates showed the highest success rate in regard to retention with a mean annual loss of retention of 1.9% (range 0%-7.6%). Three-step etch-and-rinse adhesive systems and 2-step self-etch adhesive systems showed a clinically reliable and predictably good clinical performance with a mean annual retention loss of 4.8% (range 0%-16%) and 4.7%(range 0%-19%) respectively, whereas the mean annual retention loss of 2-step etch-and-rinse adhesive systems was 6.2% (range 0%-19.5%) and that of 1-step self-etching adhesives 8.1% (range 0%-48%). However, due to the great variability a statistically significant difference was found only for glass ionomer versus 2-step etch-and-rinse and glass ionomer versus 1-step self-etch adhesive systems when the Kruskall-Wallis and Dwass-Steel-Chritchlow-Fligner test for multiple comparisons was applied. The percentage of adhesive systems--according to the adhesive category--which would get the full ADA acceptance was as follows: glass ionomer derivates 96%, 3-step etch-and-rinse 81%, 2-step self-etch 71%, 1-step self-etch 68%, 2-step etch-and-rinse 51%.

The authors concluded that although there is a tendency towards adhesives with simplified application procedures, simplification appears to induce loss of effectiveness.