中文摘要：

目的探讨在控制症状前提下,下颌智齿冠周炎初期拔牙的有效性。方法智齿冠周炎初期患者,牙根为融合根或分叉不大的二根智齿作为试验组,进行拔牙治疗;低位近中阻生或水平阻生智齿作为对照组,采取保守治疗,观察两组患者48h后肿痛症状缓解情况。结果试验组的258颗牙中,85.27%完全缓解,11.24%好转,3.48%加重;对照组的109颗牙中,21.10%完全缓解,68.80%好转,10.09%加重。试验组中48 h后治疗有效率为96.52%,对照组为89.91%,差异具有统计学意义（P〈0.05）。结论智齿冠周炎初期,在能够控制症状的前提下,拔除下颌阻生智齿可以作为一种有效的选择。

英文摘要：

Objective To explore the validity of extracting the impacted mandibular third molar in the presence of early stage of pericoronitis with symptoms under control. Methods Extraction was done in experimental group in which the wisdom teeth had fusion or small bifurcate root. Conservative treatment was carried out in control group with low-moderate impacted teeth and horizontal impacted teeth. The symptomatic relief of two groups after 48 h was observed and recorded. Results In 258 teeth of experimental group ,85.27% relieved completely in 48 h, 11. 24% improved and 3.48% have been worse. In 109 teeth of control group,21.10% relieved completely in 48 h. The symptoms were improved in 68.80% of the cases and worse in 10.09%. The effective rate in experimental group was 96.52% compared with 89.91% in control group,which demonstrated a statistical difference between two groups （P 〈 0.05）. Conclusions With symptoms under control,extracting the impacted third molar at the early stage of pericoronitis may be an effective choice.