Department of Orthodontics, Faculty of Odontology, Malmö University, Malmö, SE-205 06, Sweden.
Department of Oral Biology, Faculty of Odontology, Malmö University, Malmö, Sweden.
Arch Oral Biol. 2019 Jun;102:122-127. doi: 10.1016/j.archoralbio.2019.04.003. Epub 2019 Apr 8.
Approximately 25% of the adolescents in the Scandinavian population are treated with a fixed orthodontic appliance (FOA). Adverse effects such as enamel decalcification (white spot lesions - WSL), seem to affect over 30% of patients. WSL have only a limited ability to improve, thus seriously jeopardising the treatment outcome. The aim of present study was to explore the biofilm phenotype by investigating plaque collected: 1) adjacent to brackets, and 2) in gingival margin of maxillary incisors in adolescents with FOA. Incidence of WSL after treatment was also assessed.
In eight adolescent patients treated with FOA, supra-gingival plaque formed on: 1) brackets, and 2) along the gingival margin of the maxillary incisors, was collected after 6-8 months of treatment. The patients were documented before and after treatment by intraoral photos. Plaque samples were tested for glycosidase- (fluorogenic substrates) and protease (FITC-labelled casein substrate) activities. The plaque samples were visualised by Live/Dead BacLight stain, following which cells were investigated by confocal scanning laser microscopy.
In the collected plaque samples, all enzymes tested displayed small variations in activity between the individuals, except glucosidases, which varied significantly. Four patients developed WSL. The patients displayed higher glucosidase activity in plaque of brackets compared to patients without WSL. In seven patients, plaque at the gingival margin displayed higher protease activity than plaque of brackets.
The current study shows two distinct environmentally induced biofilm phenotypes: 1) brackets with higher glucosidase activity, and 2) gingival margin with higher protease activity. Glucosidase activity might thus be used as a putative biomarker for risk of WSL.
斯堪的纳维亚人群中约有 25%的青少年接受固定正畸矫治器（FOA）治疗。诸如釉质脱矿（白色斑点病变-WSL）等不良反应似乎影响了超过 30%的患者。WSL 的改善能力有限，因此严重危及治疗效果。本研究旨在通过研究收集的菌斑来探讨生物膜表型：1）毗邻托槽，2）在上颌切牙的牙龈边缘。还评估了治疗后 WSL 的发生率。
在 8 名接受 FOA 治疗的青少年患者中，在治疗后 6-8 个月收集了在上颌切牙的龈缘形成的超龈菌斑：1）托槽上，和 2）沿龈缘。在治疗前后通过口腔内照片记录患者。用糖苷酶（荧光底物）和蛋白酶（FITC 标记的酪蛋白底物）活性测试菌斑样本。用 Live/Dead BacLight 染色可视化菌斑样本，然后通过共聚焦扫描激光显微镜检查细胞。
在所收集的菌斑样本中，除了糖苷酶外，所有测试的酶在个体之间的活性均有较小的变化，糖苷酶的变化显著。有 4 名患者出现 WSL。与没有 WSL 的患者相比，患者的托槽菌斑中的糖苷酶活性更高。在 7 名患者中，龈缘菌斑的蛋白酶活性高于托槽菌斑。
本研究显示了两种不同的环境诱导的生物膜表型：1）托槽具有更高的糖苷酶活性，和 2）龈缘具有更高的蛋白酶活性。因此，糖苷酶活性可用作 WSL 风险的潜在生物标志物。
