Saito Kayo, Hayakawa Tohru, Kawabata Rihito, Meguro Daijiro, Kasai Kazutaka
Department of Orthodontics, Nihon University School of Dentistry at Matsudo, 2-870-1 Sakaecho Nishi, Matsudo, Chiba 271-8587, Japan.
Angle Orthod. 2007 May;77(3):532-6. doi: 10.2319/0003-3219(2007)077[0532:AAASBS]2.0.CO;2.
To produce an antibacterial adhesive for orthodontic bonding without compromising the mechanical property.
We added benzalkonium chloride (BAC) to the Superbond C&B (4-methacryloxyethyl trimellitate anhydride/methyl methacrylate-tri-n-butyl borane [4-META/MMA-TBB]), a resin that exhibits a strong bonding strength between enamel and bracket. BAC concentrations in the BAC composites were 0.25%, 0.75%, 1.25%, 1.75%, 2.5%, and 5% (wt/wt). Antibacterial activity of the BAC composite was measured by the disk diffusion method. BAC-composite discs were placed on the surface of the agar inoculated with Streptococcus mutans and Streptococcus sobrinus, and the plates were incubated at 37 degrees C. After 48 hours of incubation, the inhibition zone around each sample was measured and recorded. The BAC-modified composite was used to bond metal brackets to the phosphoric acid-etched enamel surface of human premolars. The shear bond strengths were measured after immersion in water at 37 degrees C for 24 hours.
The BAC-composite samples showed significant (P < .0001) antibacterial activity compared with the control. Measurable zones of bacterial inhibition increased as the BAC content in test samples increased. The shear bond strength declined with the increase in BAC concentration in the composite. A significant difference was found between the control composite and composites containing 1.25%, 1.75%, 2.5%, and 5% BAC (P < .05). No significant difference was found between the control composite and composites containing 0.25% and 0.75% BAC. However, shear bond strengths of the modified composites ranged from 10.12 MPa to 20.94 MPa.
These results confirmed that BAC-modified 4-META/MMA-TBB resin has a possibility for clinical application as an orthodontic bonding adhesive.
制备一种正畸粘结用抗菌粘结剂，同时不损害其机械性能。
我们将苯扎氯铵（BAC）添加到Superbond C&B（4-甲基丙烯酰氧基乙基偏苯三酸酐/甲基丙烯酸甲酯-三正丁基硼烷[4-META/MMA-TBB]）中，该树脂在釉质和托槽之间表现出很强的粘结强度。BAC复合材料中BAC的浓度分别为0.25%、0.75%、1.25%、1.75%、2.5%和5%（重量/重量）。采用纸片扩散法测定BAC复合材料的抗菌活性。将BAC复合材料圆盘置于接种变形链球菌和远缘链球菌的琼脂表面，平板在37℃下孵育。孵育48小时后，测量并记录每个样品周围的抑菌圈。将BAC改性复合材料用于将金属托槽粘结到人前磨牙的磷酸酸蚀釉质表面。在37℃水中浸泡24小时后测量剪切粘结强度。
与对照组相比, BAC复合材料样品显示出显著的（P <.0001）抗菌活性。随着测试样品中BAC含量的增加，可测量的抑菌圈增大。复合材料的剪切粘结强度随BAC浓度的增加而下降。在对照复合材料与含1.25%、1.75%、2.5%和5% BAC的复合材料之间发现有显著差异（P <.05）。在对照复合材料与含0.25%和0.75% BAC的复合材料之间未发现显著差异。然而，改性复合材料的剪切粘结强度范围为10.12MPa至20.94MPa。
这些结果证实，BAC改性的4-META/MMA-TBB树脂有可能作为正畸粘结剂临床应用。
