Comparison of microleakage between flowable nanocomposite, flowable Composite and Conventional sealant in fissure sealant therapy of the permanent teeth: an in- vitro study

Novel dental materials including nanocomposites have been introduced in recent years. It is claimed that they have superior properties such as high esthetic., low wear, increased filler content resulting in better mechanical properties, and releasing ions i.e. fluoride and amorphous calcium phosphate that are important for enamel remineralization. Considering these features, if they have retention and microleakage rates comparable with conventional sealants, these materials can be appropriate alternatives to conventional resin sealants in future.
The current study aimed at comparing . microleakage of a flowable nanocomposite, a flowable composite , and a conventional sealant in fissure sealant therapy of the permanent teeth.
First of all ,42 extracted sound human maxillary first premolars were collected and were randomly divided into 3 equal groups. Then the teeth were embedded in self-cure acrylic resin. Occlusal fissures of the samples were cleaned using explorer, enameloplasty with ¼ round diamond bur and water/air spray was done. The prepared surfaces were etched using 36% phosphoric acid gel for 15s, rinsed and dried. Bonding agent was placed in the pits and fissures, cured for 10s after thinning with air. In the first, second , and the third group conventional sealant, flowable composite , and flowable nanocomposite were placed, respectively; and light cured for 40s. The samples were thermocycled (1000 cycles between 5-55ºC) and then immersed in 2% basic Fuchsine solution for 24hs. They were then cut bucculingually and microleakage evaluation was done using stereomicroscope. The obtained data was analyzed using Kruskal wallis tests.
There was no significant difference in microleakage rate of the study groups. (P>0.05).
Considering the condition of the study, it can be concluded that flowable composite and flowable nanocomposite can be used as suitable alternatives to conventional sealants in fissure sealant therapy of the permanent teeth.