The most important criterion for restoration is that of
retention. Clinical studies have shown that restorations of
AF lesions have a higher percentage of failure in the cervical
area.[45] Restorations tend to pop off due to the constant
deformation of the tooth structure caused by parafunctional
habits. As these lesions implicate enamel and dentin margins,
they represent a challenge to the dental profession. Heymann
et al.[46] reported the association of occlusion, tooth location,
and patient’s age, with loss of retention, while others blame
the technique, marginal shrinkage, properties of the bonding
agent, and inadequate adhesive resin thickness for the
retention loss.