上顎臼歯部第2中頬側管の口腔内距離と解剖学的特徴との相関．CBCTによる研究

The Correlation between Intraorifice Distance and the Anatomical Characteristics of the Second Mesiobuccal Canal of Maxillary Molars: A CBCT Study.

抄録

はじめに:

解剖学的欠損は歯内療法の失敗の主な原因の1つであり、歯の解剖学的構造の正確な知識は適切な根管治療の前提条件である。今回のコーンビームCT（CBCT）研究の目的は、上顎臼歯部の中頬側（MB）根管の解剖学的特徴を説明し、根管開口部の位置と根の解剖学的特徴の間に相関関係が存在するかどうかを理解することである。

INTRODUCTION: Missing anatomy is one of the main causes of endodontic failures, and accurate knowledge of teeth anatomy is a prerequisite for adequate root canal treatment. The aim of the present cone beam computed tomography (CBCT) study was to describe the anatomical characteristics of the mesiobuccal (MB) root canals of maxillary molars and to understand if a correlation exists between the position of the canal orifices and the anatomical features of the root.

方法:

本研究の目的のため、2本のMB根管を有する上顎臼歯のCBCTスキャンを合計100本選択し、研究を行った。同じ歯のMB根の根管解剖学的特徴を分析し、記録した（根の長さ、合流部、Vertucci分類）。MB1およびMB2オリフィスと口蓋オリフィスとの距離、およびオリフィスと口蓋オリフィスを結ぶ線と他のオリフィスとの距離を記録した。記述的尺度、異なるパラメータ間の相関の尺度、およびMB1とMB2の合流の有無に対するこれらの尺度のいくつかの影響を示すことにより、統計的分析を行った。

METHODS: For the purposes of the study, a total of 100 CBCT scans of maxillary molars with two MB canals were selected and studied. The features of root canal anatomy of the MB root of the same teeth were analyzed and recorded (root length, confluence, and Vertucci classification). The distance between MB1 and MB2 orifices and the palatal orifice were recorded, as well as the distance between the orifices and the line joining the palatal orifice and the others. A statistical analysis was performed by providing descriptive measures, the measure of the correlation between different parameters, and the influence of some of these measures on the presence of a confluence between MB1 and MB2.

結果:

最も頻度の高い構成はII型Vertucciであった。矢状面で測定した長さは、MB根の合流部の有無と有意な相関があった。根の長さが14.56mm以上の場合、長さがそれ以下の場合に比べ、合流部の頻度は3倍高い（OR=3.635）。矢状面上の長さに対する受信者操作特性（ROC）曲線の曲線下面積（AUC）は0.632（=0.036）であった。

RESULTS: It resulted that the most frequent configuration is type II Vertucci. The length measured on the sagittal plane was significantly correlated to the presence of a confluence in the MB root. When the root length was higher than 14.56 mm, the confluence is three times more frequent than when the length is lower (OR = 3.635). The area under the curve (AUC) of the receiver operator characteristic (ROC) curve for length on the sagittal plane was 0.632 (=0.036).

結論:

上顎臼歯のMB管の合流部の有無は、矢状面上で測定可能な根の長さおよび根管開口部間の距離と相関する。解剖学的ランドマークに対する根管開口部の相対的な位置については、さらに検討する必要がある。

CONCLUSIONS: The presence of a confluence between the MB canals of maxillary molars is correlated to the length of the root that could be measured on the sagittal plane and to the distance between the canal orifices. The relative position of the root canal orifices in relation to anatomic landmarks needs to be further explored.