Dye-enhanced laser fluorescence detection of caries lesions around brackets

ArticleinLasers in Medical Science 24(6):865-870 · November 2009with56 Reads
DOI: 10.1007/s10103-008-0572-0
The aim was to evaluate the performance of DIAGNOdent [laser fluorescence(LF) and LFpen] devices enhanced by fluorescent dye in detecting mineral loss around brackets and comparing the inhibitory effect of bonding material on artificial demineralization, and to verify whether LF methods show the same trends of mineral loss. Brackets were bonded to premolar halves with Fuji Ortho LC, Transbond XT, and Ortho Glass LC cements (n = 15). The teeth were soaked in demineralizing solution (pH = 4.8) for 16days. Mineral loss was calculated by atomic emission spectrometry, and lesions were measured with LF devices with dye [tetrakis N-methylpyridyl porphyrin (TMPyP)]. Groups were compared with regard to LF readings and mineral loss, and performance of caries detection was calculated. Higher mineral loss and LF-TMPyP values occurred in the resin group. LFpen-TMPyP readings were significantly higher in the demineralized groups. Correlation was observed between mineral loss and LF measurements. LF methods are capable of identifying lower demineralization around brackets bonded with resin-modified glass ionomer cements.
    • "The initial LF values of the enamel in the resin-bonded group were 2.0 ± 0.94 and in the group bonded with GIC 1.86 ± 0.62, which correspond to the values for sound enamel reported [17,18]. In an in-vitro study [13], laser fluorescence enhanced by fluorescent dyes proved effective in detecting initial demineralization around the brackets. In this study, the porphyrin was dissolved in water and added to a lesion produced by submerging the enamel in an acetic acid solution with the pH adjusted to 4.8 for 16 days, without pH cycling. "
    [Show abstract] [Hide abstract] ABSTRACT: Objective: To evaluate in-vitro, using red laser-light induced fluorescence (LF), the effect of three fluoride compounds on the demineralization-remineralization process around brackets bonded with glass ionomer cement (GIC) or resin-based cement. Materials and method: The material comprised a sample of 60 premolars. 30 brackets were bonded with resin and 30 with glass ionomer cement. The enamel around the bracket was exposed to three demineralization– remineralization cycles to create a white spot lesion. After each cycle a fluorescent dye was applied to the enamel to measure laser fluorescence using a DIAGNOdent LF2190. The lesions were remineralized with three different commercial products: 12,000 ppm fluoride, 1,500 ppm fluoride, and 900 ppm fluoride. After pH cycles, the tooth received three weekly fluoride treatments and LF measurements with the dye were taken. Results: The initial LF values of the enamel around resin-bonded (2.0 ± 0.94) or GIC-bonded brackets (1.86 ± 0.62) showed no differences (p>0.05). After pH cycling, LF values showed no difference between the groups. The LF mean was 15.15 ± 4.28. The three fluoride compounds produced enamel remineralization around the brackets. Following fluoride treatment, a score was created based on the difference between LF post fluoride treatment and the initial LF values. These LF values showed statistical differences (p<0.001). Treatment with 900 ppm fluoride produced the highest remineralization values in both the resin and the GIC group. Conclusion: The three fluoride compounds tested had the ability to remineralize enamel lesions produced by pH cycling around brackets bonded with resin or GIC.
    Full-text · Article · Mar 2015 · Clinical Oral Investigations
    • "This phenomenon might be due to false fluorescence effects caused by dye residua of acid red in the cavity, which cannot be seen by eye but excites a primary fluorescence signal near the wave length of the fluorescence filter of the VistaProof system [39]. This effect has already been described for different dyes [40]. In reverse, when VistaProof was used during excavation, almost half of the cavities were assessed as not being caries free when inspected clinically or with caries detector. "
    [Show abstract] [Hide abstract] ABSTRACT: Caries excavation is still a demanding procedure today. In the past years, methods using light-induced fluorescence have proven their ability to detect bacteria remaining in the tooth's hard tissues. However, methods to control the complete removal of infected dentine have not yet been validated. The aim of the present study was to evaluate the degree of dentine removal during caries excavation using a camera- and software-based device as a guide for fluorescence-aided caries excavation (FACE) in comparison to visual-tactile inspection and a dye-staining method. One hundred teeth with carious lesions (C3) were randomly allocated to four groups and excavated with the respective method as primary excavation control method. When the first method indicated complete caries excavation, a second method was used to affirm this. Subsequently, dentine samples were taken to determine residual contamination using PCR. After embedding and sectioning the teeth dentine, microhardness was measured perpendicular to the cavity floor. By using the camera- and software-based device, 94 % of the cavities tested were free of bacterial contamination. All cavities excavated with the dye-staining or visual-tactile control method were free of bacterial contamination but resulted in a significantly higher dentine removal. The camera- and software-assisted caries excavation seems to be an adequate method to remove contaminated dentine without removing affected dentine. Beside its original application to monitor carious, the device is safe, effective, and easy to use for guided caries excavation and is of worth for both everyday practice and undergraduate education.
    Full-text · Article · Jul 2013
    • "The first group served as the control, whereas the teeth in other groups were immersed for 16 weeks in a cariogenic solution to produce demineralised enamel. This solution consisted of 2.2 mM CaCl 2 , 2.2 mM NaH 2 PO 4 and 50 mM acetic acid, with pH adjusted to 4.8 using KOH [24] . The specimens were immersed individually in plastic containers with approximately 10 ml of cariogenic solution, and the solution was replaced weekly. "
    [Show abstract] [Hide abstract] ABSTRACT: The aim of this investigation was to assess the effects of different treatments of demineralised enamel on microleakage under orthodontic brackets. Seventy-five intact premolars were randomly assigned to five groups. The teeth in groups 2 through 5 were immersed in a demineralising solution for 16 weeks. In groups 1 (control) and 2 (demineralised/control), conventional acid etching was used. In group 3, sodium hypochlorite (NaOCl) was applied on the enamel surface for 1 min after acid etching, and in group 4, Transbond Plus (3M Unitek, Monrovia, CA, USA) self-etching primer (SEP) was used. The teeth in group 5 were treated with 2% sodium fluoride (NaF) for 4 min before etching. After bracket bonding, the specimens were thermocycled, sealed with nail varnish, immersed in 0.5% basic fuchsine solution for 24 h and sectioned. Microleakage was measured under a stereomicroscope for the enamel-adhesive and adhesive-bracket interfaces of both occlusal and gingival sides. Demineralised teeth showed more microleakage at the enamel-adhesive interface on both occlusal and gingival sides compared to sound teeth, but the difference was not significant (P > 0.005). Treating the demineralised enamel with 5% NaOCl or Transbond Plus SEP was not effective in reducing microleakage. NaF treatment followed by acid etching of demineralised enamel resulted in significantly lower microleakage in most comparisons (P < 0.005). The use of 2% NaF on hypomineralised enamel before the bracket bonding procedure is an effective way to decrease microleakage.
    Full-text · Article · May 2013
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