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ABSTRACT: The aims of this study were to evaluate the effect of an antibacterial monomer-containing self-etching adhesive in reducing enamel demineralization around orthodontic brackets in vivo and to compare it with the conventional adhesive system quantitatively.
Fourteen orthodontic patients were randomly divided into 2 equal groups; they received brackets fitted to all their teeth, bonded with either Clearfil Protect Bond (Kuraray Medical, Okayama, Japan) (experimental group) or Transbond XT (3M Unitek, Monrovia, Calif) (control group). Block randomization to obtain equal numbers in each group was used. After 30 days, all first premolars were extracted with orthodontic indications and longitudinally sectioned. Demineralization was assessed by cross-sectional microhardness. Determinations were made at the bracket edge cementing limits and at occlusal and cervical points 100 and 200 μm away from the edge. In all of these positions, 6 indentations were made at depths of 10 to 90 μm from the enamel surface. Analysis of variance (ANOVA) and the Tukey post-hoc test were used. The statistical significance level was set at P <0.05.
ANOVA showed statistically significant differences for adhesive type, position, depth, and their interactions (P <0.05). The multiple comparison test showed that the antibacterial monomer-containing adhesive was significantly more efficient than the conventional adhesive system, reducing enamel demineralization in almost all evaluations (P <0.05).
The results indicated that using antibacterial monomer-containing adhesive for bonding orthodontic brackets successfully inhibited caries in vivo. This cariostatic effect was localized at the area around the brackets and was significant after 30 days.
American journal of orthodontics and dentofacial orthopedics: official publication of the American Association of Orthodontists, its constituent societies, and the American Board of Orthodontics 05/2011; 139(5):650-6. · 1.33 Impact Factor
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ABSTRACT: To test the null hypothesis that there is no significant difference between the chitosan-containing and conventional nonfluoridated dentifrices in inhibition of enamel demineralization around orthodontic brackets.
Sixteen orthodontic patients who were scheduled to have extraction of four first premolars for orthodontic reasons were divided into two groups after the power of the study was estimated. Patients in the experimental group were instructed to use chitosan-containing dentifrice (AloeDent), and patients in the control group were instructed to use nonfluoridated dentifrice (Sensodyne Mint). After 60 days, the teeth were extracted and longitudinally sectioned. The demineralization was assessed by cross-sectional microhardness. The determinations were made at the bracket edge cementing limits and at occlusal and cervical points, 100 µm and 200 µm away from the edge. In all these positions, indentations were made at depths of 10, 20, 30, 50, 70, and 90 µm from the enamel surface. Analysis of variance (ANOVA) and Tukey test were used for statistical evaluation at P < .05 level.
ANOVA showed statistically significant differences for the factors of dentifrice type, position, and depth (P = .000). Statistically significant differences for microhardness values between two tested dentifrices were observed up to 20 µm of depth from the enamel surface (P < .05). Lower microhardness values were found for nonfluoridated dentifrice. Significant microhardness differences were also determined between materials at occlusal and cervical 0 µm positions (P < .05). At these positions, chitosan-containing dentifrice showed lower demineralization than the control.
Chitosan-containing dentifrice may reduce the enamel decalcification found in patients with poor oral hygiene. The null hypothesis is rejected.
The Angle Orthodontist 03/2011; 81(2):319-25. · 1.21 Impact Factor
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ABSTRACT: The aims of this study were to evaluate the in-vivo reaction of newly erupted enamel to demineralization around orthodontic brackets and to compare it with that of mature enamel.
Thirteen orthodontic patients scheduled to have 4 first premolars extracted for orthodontic reasons were divided into 2 groups. Group 1 included 7 younger patients with newly erupted teeth (4 boys, 3 girls; mean age, 11.21 +/- 1.12 years; range, 11-13 years). Group 2 contained 6 adults with mature teeth (5 men, 1 woman; mean age, 34.64 +/- 4.01 years; range, 25-41 years). Brackets were placed, and, 30 days later, the teeth were extracted. These teeth were longitudinally sectioned, and demineralization was assessed by cross-sectional microhardness. Determinations were made at the bracket-edge composite limits and at occlusal and cervical points 100 mum away. Evaluations under the brackets and at the lingual surfaces were made as controls. In all these positions, 6 indentations were made at depths from 10 to 90 mum from the enamel surface. Analysis of variance (ANOVA) and Tukey tests were used for statistical evaluation at the P <0.05 level.
ANOVA showed statistically significant differences for tooth type, position, depth, and their interactions (P <0.05), except the tooth type and position interaction. The multiple comparison test showed less demineralization in the enamel around orthodontic brackets bonded to mature teeth campared with newly erupted teeth (P <0.05).
During the 30-day study period, the tooth enamel in the adult orthodontic patients was more resistant to demineralization than that of the younger patients.
American journal of orthodontics and dentofacial orthopedics: official publication of the American Association of Orthodontists, its constituent societies, and the American Board of Orthodontics 05/2010; 137(5):582.e1-6; discussion 582-3. · 1.33 Impact Factor
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ABSTRACT: A preliminary study using laser fluorescence suggested that amorphous phosphate-containing orthodontic composites may prevent demineralisation around bonded orthodontic brackets.
To compare the microhardness of the enamel around brackets bonded with an amorphous calcium phosphate-containing orthodontic composite (ACP-containing) with the microhardness of the enamel around brackets bonded with a conventional composite resin.
Forty extracted upper premolars were used. Orthodontic brackets were bonded to the teeth with either an ACP-containing composite resin (N = 20) or a conventional composite resin (N = 20). The latter were used as the control. The crowns of all teeth were painted with an acid resistant varnish, leaving a 2 mm ring of exposed enamel around the brackets. The teeth were then subjected to a daily cycle of demineralisation for 6 hours and remineralisation for 18 hours for 21 days. Each tooth was sectioned and the microhardness of the enamel determined 25, 50, 75, 100 and 150 microm from the surface.
The enamel was significantly harder 25 microm (p = 0.000) and 50 microm (p = 0.001) from the enamel surface in the teeth with brackets bonded with the ACP-containing composite resin as compared with the control teeth.
ACP-containing orthodontic composite resins may reduce the enamel decalcification found in patients with poor oral hygiene.
Australian orthodontic journal 05/2010; 26(1):10-5. · 0.25 Impact Factor
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ABSTRACT: The purpose of this in vitro study was to examine the effect of two different finishing systems on the surface roughness of different types of composite restorative materials.
Thirty specimens, 8 mm in diameter and 3 mm in depth, were prepared using a microfill composite (Clearfil ST, Kuraray Co. Ltd., Osaka, Japan), a hybrid composite (Clearfil AP-X, Kuraray Co. Ltd., Osaka, Japan), and a packable composite (Clearfil Photo Posterior, Kuraray Co. Ltd., Osaka, Japan) cured against a Mylar matrix strip to create a baseline surface. The average surface roughness was measured using a surface profilometer (Surftest 211, Mitutoyo, Japan) in five different positions on each sample before and after finishing with one of the two finishing systems [Sof-Lex discs (3M) and Po-Go (Dentsply)]. The obtained data were analyzed by two-way analysis of variance (ANOVA) at a p=0.05 significance level.
There were statistically significant differences in the average surface roughness (Ra, microm) between the Mylar matrix strip, Sof-Lex discs, and Po-Go discs (p<0.05). For all tested materials, the Mylar matrix strip provided smoother surfaces than both of the finishing systems (p<0.05). When the finishing discs were compared, Sof-Lex discs produced a smoother surface than Po-Go discs for all tested materials (p<0.05).
The Mylar matrix strip provided a smoother surface than Sof-Lex and Po-Go discs. Furthermore, Sof-Lex discs produced smoother surfaces than Po-Go discs. Sof-Lex and Po-Go systems produced clinically acceptable surface roughness for microfill, hybrid, and packable composite resin materials. The effect of finishing and polishing systems on surface roughness was dependent on both the system and the composite resin restorative material.
The journal of contemporary dental practice 02/2007; 8(2):89-96.
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ABSTRACT: This in vitro study evaluated the microleakage of Class V cavities restored with a resin composite and different adhesive systems after occlusal loading.
Standardized box-shaped Class V cavities were prepared on the buccal side of 135 non-carious human premolars. The teeth were randomly divided into three groups of 45 premolars each and restored as follows: Group 1-two-step total-etch adhesive (Single Bond, 3M) + resin composite (Supreme, 3M ESPE); Group 2-two-step self-etch adhesive (Clearfil SE, Kuraray) + resin composite and Group 3-one-step self-etch adhesive (Xeno III, Dentsply) + resin composite. The restorations were finished with aluminum oxide discs (Sof-Lex, 3M). Fifteen teeth in each group received 10,000 x 100 N and 250 N occlusal loads, respectively, and the remaining 15 teeth served as the control. The premolars were immersed in 2% methylene blue for 24 hours. The dye penetration was examined under a stereomicroscope, and the results were statistically analyzed by Kruskal Wallis, Mann-Whitney U and Wilcoxon Signed Rank tests to determine differences between the groups.
Gingival margins showed more dye penetration than occlusal margins in all the tested groups (p<0.05). In all the tested adhesive systems, 100 N occlusal loading did not change dye penetration; however, Groups 1 and 2 exhibited better marginal sealing than Group 3 at the enamel margins under 250 N occlusal loading.
Within the limitations of this in vitro study, it may be concluded that enamel margins provided better marginal sealing than dentin/cementum margins and the two-step self-etch adhesive exhibited better marginal sealing than an all-in-one adhesive at the enamel margins under 250 N occlusal loading.
Operative Dentistry 33(2):135-41. · 1.24 Impact Factor