Private Endodontic Practice, Tokyo, Japan.
Department of Endodontics, School of Dentistry, Loma Linda University, Loma Linda, California.
J Endod. 2023 Jun;49(6):664-674. doi: 10.1016/j.joen.2023.04.004. Epub 2023 Apr 20.
No clinical studies have examined the effect of mineral trioxide aggregate (MTA) obturation levels on the outcome of endodontic retreatment. This retrospective study examined treatment outcomes in three cohorts that compared overfilling, flush filling, and underfilling after orthograde retreatment using MTA.
Two hundred fifty patients with 264 teeth diagnosed with previously treated root canals and apical periodontitis retreated in a private endodontic practice were included. All teeth received MTA obturation and the extent of the final filling level was measured in relation to the major apical foramen. After 6-month follow-ups, all nonhealing cases were treated surgically. After 24- to 72-month reviews, the effect of preoperative lesion size and the degree of MTA obturation level were assessed. Multiple linear regression and time-to-event analysis using Stata 17 software (StataCorp LLC, College Station, TX) were used to evaluate the data.
Within the three cohorts, 99 out of 108 overfilled teeth (91.7%), 90 out of 103 flush fills (87.4%), and 10 out of 53 underfilled teeth (18.9%) healed and were successfully retreated without surgery at 48-months. When surgical outcomes were included, the combined healed proportion was 93.2%. Preoperative lesion size was found to be an important predictor for retreatment nonhealing. A 1-mm increase in lesion size at baseline resulted in an estimated 11% (95% CI 1.04, 1.18)-38% (95% CI 1.22, 1.58) increase in the risk of surgery. Compared to overfilling and flush filling, underfilling was associated with an approximately three-fold increase in requiring surgery and characterized by delayed healing.
MTA obturation is a viable retreatment option for teeth with nonhealing endodontic treatment. MTA overfills or flush fillings do not adversely affect healing outcomes. However, MTA underfilling increases the chances for nonhealing and surgical intervention.
目前尚没有临床研究调查过三氧化物聚合体（MTA）的充填高度对根管再治疗预后的影响。本回顾性研究对比了使用 MTA 进行直向根管再治疗时超填、平齐充填和欠填这三种情况的治疗效果。
本研究纳入了 250 名在私人牙髓病诊所接受治疗的患者，共涉及 264 颗曾接受过根管治疗且患有根尖周炎的患牙。所有患牙均接受 MTA 充填，且最后充填的高度与主根尖孔的关系都进行了测量。所有非愈合病例在 6 个月随访后均接受了手术治疗。24-72 个月后，评估了术前病变大小和 MTA 充填高度的影响。使用 Stata 17 软件（StataCorp LLC，College Station，TX）进行了多重线性回归和事件时间分析来评估数据。
在这三组中，99 颗超填牙（91.7%）、103 颗平齐充填牙（87.4%）和 53 颗欠填牙（18.9%）在 48 个月时成功地不经手术愈合并完成了再治疗。如果将手术结果也纳入考虑，总的愈合比例为 93.2%。术前病变大小是再治疗不愈合的重要预测因子。基线时病变大小增加 1mm，预计手术风险增加 11%（95%CI 1.04，1.18）-38%（95%CI 1.22，1.58）。与超填和平齐充填相比，欠填与手术需求增加约三倍相关，且具有延迟愈合的特征。
MTA 充填是治疗非愈合根管治疗的可行选择。MTA 超填或平齐充填不会对愈合结果产生不利影响。然而，MTA 欠填会增加不愈合和手术干预的可能性。
