季節も春一番、桜の開花宣言と

すっかり春めいてきました。

この時期は入社した時の緊張感を思い出し

何となく気持ちが落ち着かなくなるのは

私だけでしょうか？

さて、今回も前回に引き続き

Factors affecting the long-term results of endodontic treatmentの

Clinical and Radiographic Examination

になります。

Pain, swelling, tenderness to apical and gingival palpation,and percussion were recorded at the recall examination. Mobility of the tooth, traumatic occlusion, depth of the gingival pockets, presence of caries, and the type of restoration made on the tooth were also recorded. Radiographic examination was performed using the long-cone technique (Philips, Oralix65) with Kodak Ultraspeed film (22 • 35 mm) in a film holder (18). Two radiographs were taken on each tooth, one with an orthagonal and the other with an eccentric projection.Standardized exposure and processing were used in order to obtain optimal diagnostic quality of the radiographs. The same X-ray unit was used for all examinations and the radiographs were processed manually following the recommendations of the manufacturer.Strindberg’s (11) criteria were used to judge the success rate of root canal therapy. Treatment was considered successful when: (a) the contours, width, and structure of the periodontal margin were normal or (b) the periodontal contours were widened mainly around an excess of filling material. All cases in which those criteria were not fulfilled were judged as unsuccessful. In cases with apical radiolucencies, the size of each lesion was calculated by taking the average of the lesion’s largest dimension and its extent in the direction perpendicular to the largest dimension. The level of the root filling in relation to the root apex was also recorded. The technical standard of the root filling was judged. The root filling was considered adequate when there was no lumen apical to the filling and no void in the apical part.In evaluating the results of treatment, the radiographs were analyzed separately by two independent observers using a viewbox with variable illumination and a viewer with magnification.The observers were calibrated as described by Halse and Molven (18). Furthermore, all radiographs were evaluated twice by each observer with an interval of about 2 months between the evaluations. The intraobserver agreement was 95 and 98% for the two observers. The interobserver agreement of the judgment between the two observers was 97%. In cases of disagreement, the two observers discussed those cases in an effort to come to a consensus. If the two observers still disagreed on a particular case, the opinion of a third specialist was taken as final.Some intraobserver agreement can be expected to occur by chance. The number of diagnosis groups and their expected random frequencies are factors which influence the degree of expected random agreement. By using Cohen’s formula a correction of the agreement can be made for these expected random frequencies (19). The corrected agreement is calculated as: 「observed agreement – expected random agreement /1 – expected random agreement」 The expected random frequencies are calculated as they are in a chi-square test. In this study, the corrected agreement between the two observers was 82%.

診査は疼痛、腫脹、発赤、根尖相当部と歯肉辺縁の触診

打診痛について行われた。

また、動揺度、外傷性咬合、PPD、カリエスの有無

修復の種類も合わせて記録された。

エックス線診はStrindbergの基準に従い

根管治療の成否を判断した。

具体的には、a：歯槽硬線の外形、幅、構造が正常

又は、b：根充材のオーバー部分周囲に歯周組織の輪郭が大体広がっていること

のどちらかを満たせば、成功と見なした。

根尖透過像の大きさは、その最大長径と、それと直交する最大の長さの平均値で計算された。

根尖に対する根充材の位置も記録された。

根充は根尖側に透過像が無く、根充剤との間に中空部分も無ければ

適当と考えられた。

 この分析は2人の人によってそれぞれ2回ずつ、別々に行われた。

Cohen’s formulaを用いた所、2人の一致率は82％だった

ということです。