Bonding of Resinous Materials on Primary Enamel

Abstract

Resin sealants are accepted as an effective procedure for controlling fissure decay in primary and permanent teeth. At the same time, increased use has been reported in resin composite restoratives in posterior teeth as substitute for amalgam.Enamel acid etching is considered the most appropriate surface treatment to ensure retention of the resinous materials both on primary and permanent enamel. From the research point of view, very few studies evaluate the bonding of resinous materials on primary enamel. The parameters attributed to the bonding are usually assigned on tissues of permanent teeth and the results are merely extrapolated to primary analogues.However, chemical, physiological and micromorphological differences between primary and permanent enamel have been well established. Therefore, although bonding on primary enamel may follow the principles of adhesion of resinous materials on the hard dental tissues, the individual features of the deciduous enamel make necessary the study of the subject as a separate issue.The necessity of enamel cleaning prior to the bonding, the influence of various acid treatments on regions of the primary enamel, the bonding efficiency of resinous materials on enamel through adhesive systems and clinical data related to the retention rates of the materials are described in the present chapter. Primary Enamel;;In primary teeth the coronal part is covered by a thin enamel layer which is generally less mineralized than permanent enamel [1]. In this respect, the area of the organic/inorganic interface is greater in deciduous enamel, which contains more exogenous organic material [2]. The reduced time available for enamel maturation may account for the relatively lower mineral levels.As in the permanent enamel, the mineralization level of the deciduous enamel is characterized by the gradient from the inside to outside, albeit with a smaller relative increase [1]. A neonatal distinct line is also obvious in the primary enamel which divides the less and the more hypomineralized enamel formed before and after birth, respectively.As a consequence of the features described, the permeability of the deciduous is higher than that of the permanent enamel [1]; the latter also suggests higher porosity of the primary enamel, which leads to higher pore volume [2]. The thin-

Effect of Different Etching Times on Pit-and-Fissure Sealant Micro-Shear Bond Strength to the Enamel of Primary Teeth

“…In such patients and in children with special needs, it is difficult to maintain dryness during sealing, and therefore, shortening the etching time increases the chances of sealing success. Research is lacking in the field of primary teeth enamel etching and the relationship between the physical properties of pit-and-fissure sealants and short etching times of primary teeth enamel, probably because most of the studies to date have focused on permanent teeth [ 17 , 18 ].…”

Bond strength of conventional versus modified methods for Class IV restorations in primary incisors: An in vitro study

“…13 However, the lack of sufficient dentin structure due to the large pulp chamber, and the thin layer of prismless enamel that makes etching difficult, make the adhesive systems less effective in primary teeth. 14 , 15 …”