歯内療法治療歯の根尖周囲の健全性に及ぼす歯冠修復の影響

Influence of coronal restorations on the periapical health of endodontically treated teeth.

抄録

この研究の目的は，歯冠修復物の品質，根管閉鎖，および歯内療法を受けた歯の周囲状態の間に考えられる関係を評価することであった．オスロ大学歯学部で無作為に抽出された患者カルテの全顎X線写真シリーズを調査した．歯内療法で永久歯に修復された計1001本の歯を、2人の審査官が独立して評価した。あらかじめ設定されたX線写真の基準に従って，各歯の歯根充填の技術的品質を良好（GE）または不良（PE）のいずれかで採点し，歯冠修復の技術的品質を良好（GR）または不良（PR）のいずれかで採点した．そして，歯根とその周囲構造を評価し，歯根周囲の所見によって，治療を成功か失敗かに分類した．歯内療法を行った全歯の成功率は67.4%（n=1001）であった．根管ポストがある歯の成功率は70.7％（n＝527），ポストがない歯の成功率は63.6％（n＝472）であった．技術的に優れた歯内療法を行った2つのグループが最も高い成功率を示した．技術的に優れた修復物と組み合わせた場合の成功率は81%（GE + GR、81%）であり、技術的に劣る修復物と組み合わせた場合の成功率は71%（GE + PR、71%）であった。技術的に劣る歯内療法と良好な修復物または劣る修復物を併用した2群では，成功率が有意に低かった（PE＋GR，56%，PE＋PR，57%）．歯内療法を行った歯の根尖周囲の状態を評価する場合，X 線写真で判断される歯内療法の技術的質は，歯冠修復の技術的質よりも有意に重要であった．

The purpose of the study was to evaluate a possible relationship between the quality of the coronal restoration, the root canal obturation and the periapical status of endodontically treated teeth. Full mouth series of radiographs from randomly selected patient charts at the Dental Faculty, University of Oslo were examined. A total of 1001 endodontically treated teeth restored with a permanent restoration were evaluated independently by two examiners. According to a predetermined set of radiographic criteria, the technical quality of the root filling of each tooth was scored as either good (GE) or poor (PE), and the technical quality of the coronal restoration was scored as good (GR) or poor (PR). The root and the surrounding structures were then evaluated and according to the periradicular findings, the treatment was categorized as success or failure. The success rate for all endodontically treated teeth was 67.4% (n = 1001). Teeth with root canal posts had a success rate of 70.7% (n = 527) and teeth without posts had a success rate of 63.6% (n = 472). The two groups with technically good endodontics had the highest success rates. In combination with technically good restorations the success rate was 81% (GE + GR, 81%) and combined with technically poor restorations the success rate was 71% (GE + PR, 71%). The two groups with technically poor endodontics combined with either good restorations or poor restorations had significantly lower success rates (PE + GR, 56% and PE + PR, 57%). The technical quality of the endodontic treatment as judged radiographically was significantly more important than the technical quality of the coronal restoration when the periapical status of endodontically treated teeth was evaluated.