Dental Research Center, Dentistry Research Institute, Tehran University of Medical Sciences, Tehran, Iran.
Department of Orthodontics, Shahed University, Tehran, Iran.
Photodiagnosis Photodyn Ther. 2019 Mar;25:239-246. doi: 10.1016/j.pdpdt.2019.01.002. Epub 2019 Jan 3.
Potential complications on the crown level during fixed orthodontic procedures are white spot, enamel demineralization and tooth decay. This study evaluated the antimicrobial properties of an orthodontic adhesive incorporating cationic curcumin doped zinc oxide nanoparticles (cCur/ZnONPs), which can have the highest concentration of cCur/ZnONPs and shear bond strength (SBS) value simultaneously, against cariogenic bacteria including Streptococcus mutans, Streptococcus sobrinus, and Lactobacillus acidophilus.
Following synthesis and confirmation of cCur/ZnONPs, SBS and adhesive remnant index (ARI) of the test adhesives containing cCur/ZnONPs (1.2, 2.5, 5, 7.5, and 10% wt.) were measured using universal testing machine and stereomicroscope, respectively. After continuously rinsed (up to 180 day), the residual antimicrobial ability of modified adhesives which can have the highest concentration of cCur/ZnONPs and SBS value simultaneously were determined by disc agar diffusion (DAD), biofilm formation inhibition, and metabolic activity assays following photo-activation using light-emitting diode (LED) for 5 min against multispecies cariogenic biofilm-producing bacteria.
Adhesive with 7.5% wt. cCur/ZnONPs showed the highest concentration of cCur/ZnONPs and SBS value (14.89 ± 3.26 MPa, P < 0.05) simultaneously. No significant differences in ARI scores were found between the modified adhesive and control (Transbond XT without the cCur/ZnONPs). 7.5% wt. cCur/ZnONPs following photo-activation was not colonized by the test microorganisms and suppressed 100% metabolic activity of the test microorganisms up to 90 day compared to the control group (cCur/ZnONPs free LED irradiation; P < 0.05). In DAD assay, the reduction of photodynamic disinfection of the 7.5% wt. cCur/ZnONPs against test bacteria was positively associated to the time, in such a way that it was decreased significantly after 60 day. From days 120 onwards, microbial biofilm formation and metabolic activity was progressively increased on 7.5% wt. cCur/ZnONPs adhesive discs compared to the control group (cCur/ZnONPs free LED irradiation).
Our findings highlight the photo-activated 7.5% wt. cCur/ZnONPs can serve as an orthodontic adhesive additive to control the cariogenic multispecies biofilm, and also to reduce their metabolic activity.
固定正畸过程中牙冠表面可能出现的并发症有白斑、釉质脱矿和龋齿。本研究评估了一种正畸粘接剂的抗菌性能，该粘接剂中含有阳离子姜黄素掺杂氧化锌纳米粒子（cCur/ZnONPs），可同时达到最高浓度的 cCur/ZnONPs 和剪切粘接强度（SBS）值，针对致龋细菌包括变形链球菌、远缘链球菌和嗜酸乳杆菌。
合成并确认 cCur/ZnONPs 后，使用万能试验机和立体显微镜分别测量含有 cCur/ZnONPs（1.2、2.5、5、7.5 和 10%wt.）的测试胶粘剂的 SBS 和粘接残留指数（ARI）。经过连续冲洗（最多 180 天）后，通过使用发光二极管（LED）光激活后 5 分钟的圆盘琼脂扩散（DAD）、生物膜形成抑制和代谢活性测定，确定同时具有最高浓度的 cCur/ZnONPs 和 SBS 值的改良胶粘剂的残留抗菌能力多物种产酸生物膜形成细菌。
含 7.5%wt.cCur/ZnONPs 的胶粘剂表现出最高的 cCur/ZnONPs 浓度和 SBS 值（14.89±3.26MPa，P<0.05）。改良胶粘剂与对照（不含 cCur/ZnONPs 的 Transbond XT）之间的 ARI 评分无显著差异。与对照组（不含 cCur/ZnONPs 的 LED 照射）相比，经光激活的 7.5%wt.cCur/ZnONPs 在 90 天内未被测试微生物定植，并抑制了测试微生物 100%的代谢活性（P<0.05）。在 DAD 试验中，7.5%wt.cCur/ZnONPs 的光动力消毒对试验细菌的减少与时间呈正相关，在 60 天后显著下降。从第 120 天开始，与对照组（不含 cCur/ZnONPs 的 LED 照射）相比，7.5%wt.cCur/ZnONPs 胶粘剂盘上微生物生物膜形成和代谢活性逐渐增加。
我们的研究结果强调了光激活的 7.5%wt.cCur/ZnONPs 可用作正畸胶粘剂添加剂，以控制致龋多物种生物膜，并降低其代谢活性。
