正畸治疗中牙龈增生的致病因素分析

目的 探讨正畸治疗中牙龈增生的相关致病因素.方法 12例因接受固定正畸治疗而出现牙龈增生的患者纳入牙龈增生组,对照组为12例牙龈健康者.分别于基线时采集两组研究对象的牙周检查指标、龈下菌斑标本和龈沟液标本,采用实时PCR技术对龈下菌斑内的牙龈卟啉单孢菌（Pg）、伴放线放线杆菌（Aa）、中间普氏菌（Pi）、齿密螺旋体（Td）和福赛氏类杆菌（Tf）进行定量检测,使用ELISA法测量龈沟液中白介素-1β的含量,比较牙龈增生组和对照组各项指标间的差异.对牙龈增生组患者实施牙周基础治疗,并于4周后重新采样比较牙周治疗前后上述指标间的差异.结果 基线时,牙龈增生组中龈下菌斑内五种牙周可疑微生物的检出率均显著高于对照组（P＜0.05）,龈沟液内白介素-1β的含量显著高于对照组（P＜0.05）.牙周基础治疗后4周时,牙龈增生患者的各项牙周检查指标均明显下降,同时Pg、Aa和Td的检出率、细菌数量以及龈沟液内白介素-1β的含量均显著减少（P＜0.05）.结论 Pg、Aa和Td等牙周病原菌和白介素-1β与正畸治疗中牙龈增生的发生和发展密切相关.

Analysis of the pathogenesis of gingival enlargement in orthodontic treatment

Objective To investigate the pathogenesis of gingival enlargement (GE) in orthodontic treatment. Methods The study sample included 12 patients with GE undergoing fixed orthodontic treatment and 12 periodontally healthy controls. At baseline, periodontal variables,subgingival plaque samples and gingival cervical fluid (GCF) samples were taken from two pre-selected sites in both the GE group and control group. The levels of Porphyromonas gingivalis (Pg),Aggregatibacter actinomycetemcomitans (Aa), Prevotella intermedia (Pi), Treponema denticola (Td) and Tannerella forsythensis (Tf) were determined by real-time PCR. GCF interleukin (IL)-1β were detected by ELISA. Periodontal therapy was administered to the patients in the GE group and all the parameters were reassessed after 4 weeks. Results At baseline, the GE group showed higher prevalence of five periodontal pathogens than the control group (P＜0. 05). IL-1β levels at the GE sites were also significantly higher than those at the control sites (P＜ 0. 05). Four weeks after periodontal therapy, the GE group showed significant improvements in the clinical parameters associated with significant reductions of Pg, Aa and Td. The levels of IL-1β also decreased significantly compared with baseline (P＜0. 05). Conclusions Periodontal pathogens and IL-1β may be related to the initiation and development of GE in orthodontic treatment.