Abstract：
As already known, orthodontic treatment presents a factor of plaque retention, promoting an increase of bacterial growth in the oral cavity. Nevertheless, after orthodontic debonding an alteration of the previous microbiological status may occur. The present study was designed to assess variations among six bacterial species in the oral cavity and the status of oral health after orthodontic debonding. At the end of the fixed orthodontic treatment, 30 patients were divided into three groups based on the type of retention: I - 10 patients were treated with upper and lower fixed retention devices, II - 10 with upper and lower removable retention devices, and III - 10 with lower fixed and upper removable retention devices. To assess the alterations of oral microbiota after orthodontic debonding, two salivary swabs were collected for each individual: the first immediately after debonding (T0) and the other one 6 weeks later (T1). Six species, the ones most correlated with the development of caries and periodontal disease, were selected for microbiological analysis with Real-time PCR: Streptococcus mutans, Aggregatibacter actinomycetemcomitans, Porphyromonas gingivalis, Tannerella forsythia, Treponema denticola, and Fusobacterium nucleatum. Furthermore, in order to correlate the microbiological outcomes with the clinical condition, oral health indexes at T0 and T1 were assessed for all patients. Six weeks after debonding, the salivary levels of the bacteria investigated tend to decrease and the values of the oral health indexes tend to improve with all types of treatment considered (p<.05). Salivary bacteria levels and oral health are similarly influenced by fixed and/or removable orthodontic retentions.
摘要：
众所周知,正畸治疗是斑块保留的一个因素，促进口腔中细菌生长的增加。然而，正畸松解后，可能会发生先前微生物状态的改变。本研究旨在评估口腔中六种细菌物种之间的变化以及正畸脱胶后的口腔健康状况。在固定正畸治疗结束时，30例患者根据保留类型分为3组：I-10例患者采用上、下固定保留器治疗，II-10，带有上下可拆卸保持装置，和III-10，下部固定和上部可拆卸保持装置。为了评估正畸脱胶后口腔微生物群的变化，为每个人收集两个唾液拭子：第一个在脱粘后立即（T0），另一个在6周后（T1）。6种,与龋齿和牙周病的发展最相关的疾病，选择用于实时PCR微生物学分析：变形链球菌，放线菌聚集杆菌，牙龈卟啉单胞菌,连翘坦菌,Denticola密螺旋体,和具核梭杆菌.此外，为了将微生物学结果与临床状况相关联，对所有患者在T0和T1时的口腔健康指数进行评估.脱粘六周后，在考虑所有类型的治疗时，所研究细菌的唾液水平趋于降低，口腔健康指标值趋于改善（p<.05）。唾液细菌水平和口腔健康同样受到固定和/或可移除的正畸保留的影响。
