Korean J Orthod.  2022 Jan;52(1):75-79. 10.4041/kjod.2022.52.1.75.

Micro-computed tomographic evaluation of the effect of fluoride agents on white spot lesions: An in vitro study

• Hong SC
• Lee DY
• Kim YJ

• KMID: 2524904
• DOI: http://doi.org/10.4041/kjod.2022.52.1.75

Abstract

Objective
To investigate remineralizing effect of three fluoride regimens on artificially demineralized enamel around orthodontic bracket by analyzing mineral density (MD) acquired from micro-computed tomography (micro-CT).
Methods
Forty-eight bracket bonded bovine incisors were prepared to create demineralized enamel (DE) surface. The samples were divided into four groups according to the fluoride regimen: 1) no fluoridation, 2) 1.23% acidulated phosphate fluoride (APF) gel, 3) fluoridated toothpaste, and 4) 0.05% sodium fluoride mouthwash. Micro-CT was scanned after demineralization (T0), and 2 weeks (T1) and 4 weeks (T2) of fluoridation.
Results
APF gel showed highest remineralization of DE during T1–T0 interval among the groups (p < 0.05); followed by toothpaste, mouthwash and no fluoridation. APF gel and toothpaste demonstrated significant increase in MD after 4 weeks of application (p < 0.05).
Conclusions
Remineralization effects of three fluoride regimens were depicted through micro-CT analysis, of which APF gel was most effective.

Keyword

Cariology; Fluoride; Micro-computed tomography

Figure

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  Figure 1 Two dimensional micro-computed tomography images. The arrows indicate mineral density changes as depicted by the gray scale at T0, after demineralization; and T1, 2 weeks and T2, 4 weeks of fluoridation.

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  Figure 2 Mean mineral density (vol%) at various depths of enamel in each group. Group 1, no treatment; Group 2, 1.23% acidulated phosphate fluoride gel; Group 3, fluoridated toothpaste; Group 4, 0.05% sodium fluoride mouthwash solution; SE, sound enamel; T0, after demineralization; T1, 2 weeks of fluoridation; T2, 4 weeks of fluoridation.

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  Figure 3 Total remineralization changes in each group over the course of the 4-week fluoridation regimen at various enamel depths. Group 1, no treatment; Group 2, 1.23% acidulated phosphate fluoride gel; Group 3, fluoridated toothpaste; Group 4, 0.05% sodium fluoride mouthwash solution.

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