Bhattacharjee Debarshi, Sharma Kanchan, Sahu Rajalaxmi, Neha Komal, Kumari Archana, Rai Anurag
Department of Orthodontics and Dentofacial Orthopaedics, Awadh Dental College and Hospital, Jamshedpur, Jharkhand, India.
Department of Orthodontics and Dentofacial Orthopaedics, Patna Dental College and Hospital, Patna, Bihar, India.
J Pharm Bioallied Sci. 2021 Nov;13(Suppl 2):S1168-S1173. doi: 10.4103/jpbs.jpbs_412_21. Epub 2021 Nov 10.
The shear bond strength obtained with an acid primer might not be clinically reliable. The present study evaluated the use of a new self-etch primer as compared with the conventional bonding procedure. The findings indicated that the use of a self-etch primer to bond orthodontic brackets to the namel surface provided lower, but clinically accept-able, shear bond forces (mean, 7.1 ± 4.4 MPa). Hence, this study has been designed to evaluate the shear bond strength of orthodontic brackets bonded with a self-etching primer system, and compare it with the conventional acid etching priming system.
This study was designed to compare the shear bond strength of orthodontic brackets bonded with conventional acid etching- priming and a self-etching primer. For this purpose, one hundred and twenty noncarious, not subjected to any pretreatment chemical agents (e.g. hydrogen peroxide), no cracks caused by the presence of the extraction forceps, no caries and unrestored human maxillary 1 and 2 premolars, freshly extracted for orthodontic treatment were collected and stored in distilled water before bonding. Separate molds of cold-cure acrylic were prepared and the extracted premolar teeth were embedded in the cold cure acrylic up to the cement enamel junction.
For the control group, the mean shear bond strength was 9.38 ± 6.02 MPa and for the experimental group, it is 6.91 ± 3.58 MPa. Group comparison using Chi-square test for the self-etching primer group adhesive remnant index (ARI) scores shows that more than half of the adhesive left over the tooth surface (score 3 and 4). For the conventional group, ARI scores show that there was no or slight amount of adhesive left over the tooth surface (score 5). The proportion of ARI score is significantly ( < 0.001) more in conventional (68.33%) as compared to self-etch primer (SEP) (28.33%). The proportion of ARI scores 4 and less is significantly more in SEP (71.67%) as compared to Conventional (6.67%) with = 0.004 as per the Chi-square test.
The bond strength of SEP is comparatively lesser than the conventional acid etching technique, but is definitely more or less to the required bond strength to resist masticatory forces. Majority of the studies conducted on self-etching primer are studies. Results of these cannot be extrapolated to the intraoral environment. Hence, further long-term clinical studies need to be carried out before actually recommending the use of self-etching primer in routine orthodontic bonding.
使用酸性底漆获得的剪切粘结强度在临床上可能不可靠。本研究评估了一种新型自酸蚀底漆与传统粘结程序相比的使用情况。研究结果表明，使用自酸蚀底漆将正畸托槽粘结到牙面可提供较低但临床上可接受的剪切粘结力（平均值为7.1±4.4兆帕）。因此，本研究旨在评估用自酸蚀底漆系统粘结正畸托槽的剪切粘结强度，并将其与传统酸蚀底漆系统进行比较。
本研究旨在比较用传统酸蚀底漆和自酸蚀底漆粘结正畸托槽的剪切粘结强度。为此，收集了120颗非龋、未经过任何预处理化学剂（如过氧化氢）处理、不存在因拔牙钳导致的裂纹、无龋且未修复的人类上颌第一和第二前磨牙，这些牙齿是为正畸治疗而新鲜拔除的，在粘结前保存在蒸馏水中。制备了单独的冷固化丙烯酸模具，并将拔除的前磨牙嵌入冷固化丙烯酸中，直至牙骨质釉质交界处。
对照组的平均剪切粘结强度为9.38±6.02兆帕，实验组为6.91±3.58兆帕。对自酸蚀底漆组的粘结剂残留指数（ARI）评分进行卡方检验的组间比较显示，超过一半的粘结剂留在牙面上（评分为3和4）。对于传统组，ARI评分显示牙面上没有或仅有少量粘结剂残留（评分为5）。与自酸蚀底漆（SEP）组（28.33%）相比，传统组的ARI评分比例显著更高（<0.001）（68.33%）。根据卡方检验，ARI评分为4及以下的比例在SEP组（71.67%）中显著高于传统组（6.67%），P=0.004。
SEP的粘结强度相对低于传统酸蚀技术，但肯定或多或少达到了抵抗咀嚼力所需的粘结强度。大多数关于自酸蚀底漆的研究都是体外研究。这些研究结果不能外推至口腔内环境。因此，在实际推荐在常规正畸粘结中使用自酸蚀底漆之前，需要进行进一步的长期临床研究。
