BACKGROUND Adhesion strength of orthodontic attachments to enamel should be within optimal range to resist occlusal forces and to allow debonding without enamel damage. OBJECTIVE The present study compared the effect of non-thermal plasma (NTP) and conventional surface treatment on the adhesion strength of orthodontic bracket to enamel. METHODS A total of 100 premolar teeth were allocated into 5 groups according to the bonding procedure followed: Group 1 (Etch, prime and composite adhesive); Group 2 (Prime and composite adhesive); Group 3 (Glass ionomer cement); Group 4 (NTP, prime and composite adhesive) and Group 5 (NTP and glass ionomer cement). Ten specimens in each group were subjected to artificial aging and the remaining ten specimens served as baseline specimens. Adhesion strength values were recorded after debonding and bond failure types were scored. Water contact angles of the NTP treated and untreated enamel surface were measured. RESULTS Group 1 specimen demonstrated highest bond strength at baseline (21.5 ± 3.01) and thermocycling (15.8 ± 2.87) and the least values were in Group 2 specimens at baseline (3.9 ± 1.01) and thermocycling (1.6 ± 0.7). Among the experimental (NTP) groups, Group 4 specimens exhibited high adhesion strength at baseline (10.2 ± 1.76) and after thermocycling (9.8 ± 2.15) compared to Group 5 specimens at baseline (10.1 ± 1.05) and thermocycling (6.5 ± 2.19). The water contact angle on untreated enamel surface was 53.1° ± 2.1° as compared to 1.4° ± 0.7° in treated surface. CONCLUSION Non-thermal plasma (NTP) treatment in conjunction with composite adhesives demonstrated clinically acceptable adhesion strength and was well within the optimal range (7-14 MPa) for enamel bonding.

中文翻译：

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非热等离子体处理可增强釉质表面和正畸托槽之间的附着力。

背景技术正畸附着物对牙釉质的粘附强度应在最佳范围内，以抵抗咬合力并允许脱粘而不会损害牙釉质。目的本研究比较了非热等离子体（NTP）和常规表面处理对正畸托槽对牙釉质粘附强度的影响。方法按照以下步骤将总共100颗前磨牙分为5组：第1组（蚀刻，底涂和复合胶粘剂）；第1组。第二组（底漆和复合胶）；第3组（玻璃离聚物水泥）；第4组（NTP，底漆和复合粘合剂）和第5组（NTP和玻璃离聚物水泥）。每组十个样品进行人工时效，其余十个样品用作基线样品。剥离后记录粘合强度值，并对粘合破坏类型进行评分。测量了NTP处理和未处理的搪瓷表面的水接触角。结果第1组样品在基线（21.5±3.01）和热循环（15.8±2.87）处显示出最高的粘结强度，而在第2组样品在基线（3.9±1.01）和热循环（1.6±0.7）处具有最小的粘合强度。在实验（NTP）组中，与第5组在基线（10.1±1.05）和热循环（6.5±2.19）时相比，第4组样品在基线（10.2±1.76）和热循环后（9.8±2.15）表现出高粘附强度。未经处理的瓷釉表面的水接触角为53.1°±2.1°，而经处理的表面为1.4°±0.7°。