Effect of remineralizing agents on bond strength of orthodontic brackets: an in vitro study

Abstract

BackgroundThe purpose of this study is to evaluate the effect of casein phosphopeptide amorphous calcium phosphate (CPP-ACP) and CPP-ACP with fluoride (CPP-ACP-F) on the shear bond strength (SBS) of orthodontic brackets bonded with two different adhesive systems.MethodsOne hundred twenty-six human premolar teeth were selected. One hundred twenty teeth were used for SBS testing, and six teeth were used for scanning electron microscope (SEM) examination. One hundred twenty premolars were divided into mainly three groups: CPP-ACP (group A), CPP-ACP-F (group B), and control group (group C). Each group was sub-divided into two groups according to the bonding adhesive, light cure (groups A1, B1, and C1) and chemical cure (groups A2, B2, and C2). The teeth were pre-treated with the group-specified preventive agent 1 h/day for five consecutive days. Standard edgewise brackets were bonded with the respective adhesives. SBS evaluation was done with the universal testing machine. After debonding, all the teeth were scored for adhesive remaining on the buccal surface, in accordance to adhesive remnant index, under a stereomicroscope. The acid-etched enamel surfaces were observed under SEM after treatment with CPP-ACP, CPP-ACP-F, and artificial saliva.ResultIn light-cure adhesive group, CPP-ACP-F (B1) showed superior results compared to the control group (C1), whereas the CPP-ACP group (A1) showed lower mean SBS than the control group (C1). Both these differences were not statistically significant (p > 0.05). In chemical-cure adhesive group, control group C2 showed significantly superior results (p < 0.05) compared to group A2 and group B2. The results of two-way ANOVA showed highly significant difference due to adhesive types (p < 0.01), whereas enamel pre-treatment showed non-significant difference (p > 0.01).ConclusionThe SBS of the orthodontic brackets was non-significantly affected when the brackets were cured with light-cure bonding system and treated with either CPP-ACP or CPP-ACP-F, whereas with chemical-cure adhesive, decreased bond strength was seen, which was within the clinically acceptable limits.

Effect of CO2 Laser and Fluoride Varnish Application on Microhardness of Enamel Surface Around Orthodontic Brackets

“…Present study showed a statistically significant difference between groups regarding the distribution of ARI scores and more bond failure distributions were at the enamelbracket interface in groups 2 to 5 and at the bracketadhesive interface in the control group. The results of Ladhe et al 11 and Leódido et al 39 studies about ARI were similar to ours. While in the present study, microbiological model was used for demineralization to simulate clinical situation, saliva components and temperature conditions of the oral cavity can affect the effect of caries preventive materials.…”

“…Fluoride varnish is easy to use and does not depend on patient's cooperation. 11,14 For patients with moderate to high risk of caries, fluoride regimen should be used at office every six months. 10 Since the intervention of ruby crystal laser by Maiman in 1960, different lasers have been assessed in dentistry fields.…”

“…Fluoride effects with different mechanisms: It joins the crystalline structure of hydroxy apatite and creates fluoride hydroxy apatite that is less soluble and more resistant to acidic attack, it increases the remineralization process and has antibacterial effects. [11][12][13] There are different types of fluoride with different pH, concentration and releasing systems such as varnish, gel, mouth-rinse and tooth paste. Complete compliance of patients with fluoride regimen at home is unlikely.…”

Biomimetic Effect of Nano-Hydroxyapatite in Demineralized Enamel before Orthodontic Bonding of Brackets and Attachments: Visual, Adhesion Strength, and Hardness in In Vitro Tests

“…Previous studies in the literature evaluated ARI scores after remineralizing agent application, showing conflicting results, with ARI score prevalence ranging from minimum to maximum values [33,35,36,41]. However, a direct comparison with the results of the present report is difficult, as biomimetic nano-hydroxyapatite has not been tested yet.…”

“…Higher bond values were reported when comparing remineralized enamel with demineralized enamel [33]. However, when remineralizing agents were compared with normal enamel, similar [35] or lower [36] bond strength values were reported.…”