Orthodontics, Faculty of Dentistry, University of Hong Kong, SAR China.
Eur J Orthod. 2011 Oct;33(5):577-83. doi: 10.1093/ejo/cjq126. Epub 2010 Dec 27.
The aim of this study was to investigate the morphological features and distribution of biofilms on Invisalign orthodontic appliances, in a sample of 'slow' and 'fast' plaque formers using scanning electron microscopy (SEM). Fifty-six Chinese male/female volunteers (aged 19-39 years) were screened for their plaque-forming rate using the plaque percentage index (PPI) coupled with digital photography and computer-based image analysis, after a period of 48 hours of abstinence from oral hygiene procedures. Eleven volunteers (seven males/four females) representing the lowest and highest ends of the plaque formation spectrum were chosen as slow and fast plaque formers, respectively. The subjects wore a full-coverage splint appliance, in which four tiles of Invisalign material were embedded. These tiles were collected at intervals of 1, 3, 6, 12, 24, and 48 hours, as well as 3, 7, and 14 days, immediately fixed in 10 per cent paraformaldehyde in 0.2 M cacodylate buffer solution and prepared for SEM. The surface configuration of the Invisalign appliance was visualized, as well as the chronological pattern of biofilm formation. Significance between fast and slow plaque formers was determined using a Student's t-test. Colonization appeared to centre initially on the raised edges or textured surfaces of the appliance, and initial adhesion was quicker and more abundant in the fast plaque-forming group. In the later stages of biofilm development, both groups showed no discernible differences in biofilm accrual on the surfaces, but the fast group displayed a more complex biofilm structure. More recessed and sheltered areas of the appliance, such as the cusp tips and attachment dimples, harboured more biofilm than the flat surfaces. Hence, it seems that the novel Invisialign orthodontic appliance is a useful tool to investigate the features of biofilm formation in time-course studies.
本研究旨在使用扫描电子显微镜（SEM）研究隐形矫正器上生物膜的形态特征和分布，该研究样本包括使用菌斑百分率指数（PPI）结合数码摄影和基于计算机的图像分析筛选出的“慢”和“快”菌斑形成者。在 48 小时不进行口腔卫生程序后，对 56 名中国男女志愿者（年龄 19-39 岁）的菌斑形成率进行了筛查。选择菌斑形成率最低和最高的 11 名志愿者（7 名男性/4 名女性）分别作为慢和快菌斑形成者。受试者佩戴全覆盖夹板矫治器，其中嵌入了 4 块 Invisalign 材料。这些嵌体分别在 1、3、6、12、24 和 48 小时以及 3、7 和 14 天时进行收集，立即固定在 10%的多聚甲醛中，用 0.2 M 的碳二亚胺缓冲液，并准备进行 SEM。观察隐形矫正器的表面结构以及生物膜形成的时间模式。使用学生 t 检验确定快和慢菌斑形成者之间的显著性。定植似乎最初集中在矫治器的凸起边缘或纹理表面上，并且在快菌斑形成组中初始粘附更快且更丰富。在生物膜发展的后期阶段，两组在表面生物膜的积累方面没有明显差异，但快组显示出更复杂的生物膜结构。矫治器的更凹陷和隐蔽区域，如牙尖和附着凹坑，比平面表面容纳更多的生物膜。因此，似乎新型 Invisalign 正畸矫治器是研究时间进程中生物膜形成特征的有用工具。
