The effect of delaying composite resin restoration after silver diamine fluoride pretreatment on the Shear Bond Strength of the final restoration : An in-vitro study

Abstract

Abstract Background: Silver Diamine Fluoride (SDF) is a promising caries arresting material that can prevent recurrent caries when applied prior to composite resin. However, SDF can negatively affect the shear bond strength (SBS) of dental adhesives. Thus, the aim of the current study was to investigate the effect of delaying final restoration for one week after SDF pretreatment on shear bond strength of composite resin.Materials and methods: Sixty-six extracted sound primary teeth were randomly allocated to one of three groups as follows ; Group 1 (Control group): composite restoration without pretreatment, group 2: 38% SDF pretreatment + immediate composite restoration, group 3: 38% SDF pretreatment + 1-week aging + composite restoration. Each group was further divided into two subgroups according to the bonding protocol used as follows: (Subgroup ER) etch-and-rinse technique and (Subgroup SE) self-etch technique. SDF and composite resin were applied to the flattened buccal dentinal surfaces. SBS was measured using universal testing machine. Mode of failure was assessed by stereomicroscope. Elemental contents and depth of penetration were assessed using energy dispersive x-ray stereoscopy (EDS).Results: A statistically significant difference in mean SBS was found between group 2 (39.88±27.35) and group 1 (85.17 ± 40.43), but no significant difference was found between group 3 (96.70 ± 30.28) and group 1 (85.17 ± 40.43). Moreover, there was a statistically significant difference in mean SBS between subgroup 2ER (52.23 ± 30.13) and 2SE (27.53± 18.11). EDS analysis revealed deeper penetration of silver ions over time.Conclusions: Delaying composite resin restoration bonding to primary dentin for one week after SDF pretreatment eliminated any negative impact on SBS of the final restoration.