Akin Mehmet, Baka Zeliha Muge, Ileri Zehra, Basciftci Faruk Ayhan
Department of Orthodontics, Faculty of Dentistry, University of Selçuk , Konya, Turkey.
Acta Odontol Scand. 2014 May;72(4):283-9. doi: 10.3109/00016357.2013.823646. Epub 2013 Aug 22.
To evaluate and compare the effects of enamel demineralization, microabrasion therapy and casein phosphopeptide-amorphous calcium phosphate (CPP-ACP) application on the shear bond strength (SBS) of orthodontic brackets bonded to enamel surfaces and enamel color.
Eighty freshly extracted human maxillary premolar teeth were allocated to one of the four groups. Brackets were bonded directly to non-demineralized enamel surfaces in Group I (control group), directly to the demineralized enamel surfaces in Group II, to demineralized enamel surfaces after CPP-ACP application in Group III and to demineralized enamel surfaces after microabrasion therapy in Group IV. The samples were stored in water for 24 h at 37°C and then underwent thermocycling. The SBS in megapascals (MPa) was determined by a shear test with 0.5 mm/min crosshead speed and failure types were classified with modified adhesive remnant index scores. The data were analyzed with one-way analyses of variance (ANOVA), Tukey and chi-square tests at the α = 0.05 level.
Significant differences were found among the four groups (F = 21.57, p < 0.01). No significant difference was found between Group I and III (17.12 ± 2.84 and 15.08 ± 3.42 MPa, respectively) or between Group III and IV (12.82 ± 2.64 MPa). The lowest SBS value was determined in Group II (5.88 ± 2.12 MPa). Enamel demineralization, microabrasion therapy and CPP-ACP application affected enamel color significantly.
CPP-ACP application and microabrasion therapy are able to increase the decreased SBS of orthodontic brackets because of enamel demineralization.
评估并比较牙釉质脱矿、微研磨治疗以及酪蛋白磷酸肽-无定形磷酸钙（CPP-ACP）应用对正畸托槽与牙釉质表面粘结的剪切粘结强度（SBS）及牙釉质颜色的影响。
80颗新鲜拔除的人类上颌前磨牙被分配到四组中的一组。在第一组（对照组）中，托槽直接粘结到未脱矿的牙釉质表面；在第二组中，直接粘结到脱矿的牙釉质表面；在第三组中，在应用CPP-ACP后粘结到脱矿的牙釉质表面；在第四组中，在微研磨治疗后粘结到脱矿的牙釉质表面。样本在37℃水中储存24小时，然后进行热循环。以0.5毫米/分钟的十字头速度通过剪切试验测定以兆帕（MPa）为单位的SBS，并使用改良的粘结剂残留指数评分对失败类型进行分类。数据在α = 0.05水平下采用单因素方差分析（ANOVA）、Tukey检验和卡方检验进行分析。
四组之间存在显著差异（F = 21.57，p < 0.01）。第一组和第三组之间（分别为17.12 ± 2.84和15.08 ± 3.42 MPa）或第三组和第四组之间（12.82 ± 2.64 MPa）未发现显著差异。第二组中确定的SBS值最低（5.88 ± 2.12 MPa）。牙釉质脱矿、微研磨治疗和CPP-ACP应用对牙釉质颜色有显著影响。
由于牙釉质脱矿，应用CPP-ACP和微研磨治疗能够提高正畸托槽降低的SBS。
