皆さん、根管治療の成功率は何%か御存知でしょうか？

私達医療者は患者様の為に最善を尽くしますが

それでも100%の成功率の根管治療というものは

現在の所、存在しません。

この点について詳しく述べられているSjogrenの論文

Factors affecting the long-term results of endodontic treatment

Journal of Endodontics Volume 16, Issue 10, Pages 498-504, October 1990

を今回から数回に分けて紹介していきたいと思います。

導入

Numerous studies have been published evaluating success and failure of endodontic therapy (t-12). Success rates varying from 40 to 93% have been reported (1, 4, 8). The wide range in success rate may depend on differences in experimental design and clinical procedures, criteria for evaluation of the periapical healing, and the length of the postoperative observation period. It is likely, however, that the most important factor influencing the prognosis of endodontic treatment is the preoperative status of the teeth. A large number of studies have demonstrated that the success rate in endodontic therapy is significantly influenced by the presence or absence of a pretherapeutic radiographic lesion (1-7, 9-11). Teeth with an apical radiolucency may show up to 20% lower success rate than teeth without such lesions (2, 3, 11).In a recent study, we found that the healing pattern of periapical lesions was dependent on the initial size of the radiographic lesion and that an observation period of 5 yr was necessary before complete healing had taken place (13).

This is in agreement with Strindberg’s (11) original observation that the disappearance of periapical lesions occasionally could　take up to 9 yr following treatment. The uncertainty which exists concerning the influence of size of the preoperative periapical lesion (2, 6, 8, 10), and the effect of excesses of root-filling material in periapical tissues (10, 1 l, 14) on the outcome of endodontic treatment may be due to too short　observation periods.

When strict anaerobic techniques were applied to endodontic samples, it was found that obligate anaerobic bacteria dominated in infected root canals and could constitute as　much as 90% of the flora (15, 16). The decisive role of bacteria for the development of apical periodontitis was revealed when these techniques were used (16, 17). These techniques were　not available when earlier studies evaluating success and failure of endodontic therapy were made (2, 9, 12) and were not used in later studies (1, 5, 6).

The aim of the present study was to assess the long-term results of endodontic treatment and to determine the influence of various factors on the outcome of treatment when the treatment had been controlled with anaerobic bacteriological techniques.

根管治療の成功率はある文献では40～93％

と言われる様に、非常に幅広く

これは研究デザインや臨床術式や

治癒に対する基準や外科後の観察期間が

統一されていないことに因る。

この研究では長期症例における治療結果を評価することと

治療結果に影響を与える因子を

決定することを目的に行われた

ということです。