With regard to permanent teeth, there is insufficient evidence to support the use of RMGIC as long term restorations in permanent teeth. Despite the low number of randomised control trials, a meta- analysis review by Bezerra et al. [2009] reported significantly fewer carious lesions on the margins of glass ionomer restorations in permanent teeth after six years as compared to amalgam restorations.  In addition, adhesive ability and longevity of GIC from a clinical standpoint can be best studied with restoration of non- carious cervical lesions. A systematic review shows GIC has higher retention rates than resin composite in follow up periods of up to 5 years. Unfortunately, reviews for Class II restorations in permanent teeth with glass ionomer cement are scarce with high bias or short study periods. However, a study  [2003] of the compressive strength and the fluoride release was done on 15 commercial fluoride- releasing restorative materials. A negative linear correlation was found between the compressive strength and fluoride release (r=0.7741), i.e., restorative materials with high fluoride release have lower mechanical properties.