Matea Tomljanovic, Matea Badnjevic, Martina Zigante, Anbo Dong, Svetislav Zaric, Stjepan Spalj, Tomljanovic Matea
Faculty of Dental Medicine, Department of Orthodontics, University of Rijeka, Kresimirova 40, Rijeka, Croatia.
Faculty of Medicine, University of Rijeka, Rijeka, Croatia.
Clin Oral Investig. 2025 Jul 21;29(8):387. doi: 10.1007/s00784-025-06406-1.
Endotoxin is a component of the outer membrane of gram-negative bacteria; it adheres to orthodontic brackets and contributes to inflammation of adjacent gingival tissues. This study investigated the effects of chlorhexidine (CHX) and appliance material on plaque control, gingivitis, and subgingival endotoxin activity during the initial phase of orthodontic treatment.
Sixty-eight participants aged 12-18 years (50% females) were recruited and randomized into groups based on appliance material (metal vs. nonmetal) and CHX use. The plaque and gingival indices, plaque pH, and subgingival endotoxin activity were assessed before appliance placement (T0) and two months after the commencement of orthodontic treatment (T1).
There were no significant differences in the changes in endotoxin activity, periodontal status, and plaque pH (ΔT1-T0) between the metal and nonmetal groups regardless of CHX usage. Gingivitis decreased in the nonmetal appliance group with standard oral hygiene (p = 0.033). Endotoxin activity at T1 was correlated with the extent of gingivitis (r = 0.459; p < 0.001) and plaque accumulation (r = 0.264; p = 0.035). Multiple regression analysis revealed that after controlling for the effects of sex, appliance material, and CHX, the predictors of gingivitis after 2 months of orthodontic treatment were increased endotoxin activity (p = 0.004), increased plaque index (p = 0.005), and older age (p = 0.043).
The early impacts of metal and nonmetal orthodontic appliances on gingival inflammation and plaque accumulation are similar, with changes in the extent of gingivitis linked to endotoxin levels rather than appliance type or CHX use.
Gingivitis during orthodontic treatment is mostly related to efficient plaque control and not to appliance material.
内毒素是革兰氏阴性菌外膜的一种成分；它附着于正畸托槽并导致相邻牙龈组织炎症。本研究调查了洗必泰（CHX）和矫治器材料在正畸治疗初始阶段对菌斑控制、牙龈炎和龈下内毒素活性的影响。
招募68名年龄在12 - 18岁的参与者（50%为女性），根据矫治器材料（金属与非金属）和CHX使用情况随机分组。在放置矫治器前（T0）和正畸治疗开始两个月后（T1）评估菌斑和牙龈指数、菌斑pH值以及龈下内毒素活性。
无论是否使用CHX，金属组和非金属组在内毒素活性、牙周状况和菌斑pH值变化（ΔT1 - T0）方面均无显著差异。采用标准口腔卫生措施的非金属矫治器组牙龈炎有所减轻（p = 0.033）。T1时的内毒素活性与牙龈炎程度（r = 0.459；p < 0.001）和菌斑积聚（r = 0.264；p = 0.035）相关。多元回归分析显示，在控制了性别、矫治器材料和CHX的影响后，正畸治疗2个月后牙龈炎的预测因素为内毒素活性增加（p = 0.004）、菌斑指数增加（p = 0.005）和年龄较大（p = 0.043）。
金属和非金属正畸矫治器对牙龈炎症和菌斑积聚的早期影响相似，牙龈炎程度的变化与内毒素水平有关，而非矫治器类型或CHX的使用。
正畸治疗期间的牙龈炎主要与有效的菌斑控制有关，而非矫治器材料。
