Petti S, Barbato E, Simonetti D'Arca A
Hygiene Institute, La Sapienza University of Rome, Italy.
New Microbiol. 1997 Jan;20(1):55-62.
The present study evaluated microbiological and clinical changes occurring during the first six months of orthodontic therapy with fixed and removable appliances and the consequent risk for gingivitis and periodontal disease. This study was justified by the disagreement among different authors: only some of them reported gingivitis development and changes in dental plaque composition during orthodontic therapy with fixed appliances, others did not. Thirty, 7-to-15-year-old children, fifteen with fixed and fifteen with removable appliances, previously motivated to oral hygiene, completed the study. They were clinically examined by a dentist at baseline and at the end of the study. Three supra and subgingival microflora samples were collected from the first molars, when the appliances were inserted (T0), 6-8 weeks later (T1) and 6-7 months later (T2). Microflora was examined using dark-field and light microscopes and cultural methods. An indicator of healthy status (percentage of Gram positive cocci in total bacterial count) and some risk indicators for gingivitis (bacterial count evaluated with light microscope, percentage of Gram negative rods) and for periodontitis (motile rod and spirochete percentages, presumptive Actinobacillus actinomycetemcomitans and Porphyromonas gingivalis prevalence) were investigated. Patients with fixed appliances were clinically healthy at T2; yet they showed significantly increased counts, motile rods, subgingival spirochetes and a decrease of Gram positive cocci. At T2, patients with removable appliances were clinically healthy and the only significant microbiological changes were supragingival motile rods and subgingival spirochetes. These data suggest that in the oral hygiene motivated patients of the present study, gingivitis and periodontitis do not occur, during the first six months of treatment: the significant modification of oral microbiota, shown by subjects with fixed appliances, however, suggests that the risk for gingivitis in the following months of therapy is still high and the risk for periodontitis cannot be excluded.
本研究评估了使用固定矫治器和活动矫治器进行正畸治疗的前六个月期间发生的微生物学和临床变化，以及随之而来的牙龈炎和牙周疾病风险。不同作者之间存在分歧，这为本研究提供了依据：只有部分作者报告了使用固定矫治器进行正畸治疗期间牙龈炎的发展和牙菌斑成分的变化，其他作者则未报告。30名7至15岁的儿童完成了本研究，其中15名使用固定矫治器，15名使用活动矫治器，他们之前均接受过口腔卫生宣教。在基线期和研究结束时，由一名牙医对他们进行临床检查。在矫治器戴入时（T0）、6 - 8周后（T1）和6 - 7个月后（T2），从第一恒磨牙采集三份龈上和龈下微生物样本。使用暗视野显微镜、光学显微镜和培养方法对微生物进行检查。研究了健康状况指标（革兰氏阳性球菌在总细菌计数中的百分比）以及一些牙龈炎风险指标（用光学显微镜评估的细菌计数、革兰氏阴性杆菌的百分比）和牙周炎风险指标（活动杆菌和螺旋体百分比、推定的伴放线放线杆菌和牙龈卟啉单胞菌患病率）。使用固定矫治器的患者在T2时临床健康；然而，他们的细菌计数、活动杆菌、龈下螺旋体显著增加，革兰氏阳性球菌减少。在T2时，使用活动矫治器的患者临床健康，唯一显著的微生物学变化是龈上活动杆菌和龈下螺旋体。这些数据表明，在本研究中接受过口腔卫生宣教的患者中，治疗的前六个月未发生牙龈炎和牙周炎：然而，使用固定矫治器的受试者口腔微生物群的显著改变表明，在治疗的接下来几个月中牙龈炎风险仍然很高，牙周炎风险也不能排除。
