電気歯髄検査値の差と歯髄炎の診断タイプとの関係

Relationship between the difference in electric pulp test values and the diagnostic type of pulpitis.

抄録

背景:

アメリカ歯内療法学会（AAE）の診断基準によると、歯髄炎の診断には、疑わしい歯の冷熱反応を対照歯と比較することが用いられるが、電気パルプテスト（EPT）の役割については言及されていない。EPTは、歯髄の活力を判断する上でいくつかの限界があると考えられている。本研究の目的は，EPTの値の違いと，う蝕による可逆性歯髄炎（RP）および症候性不可逆性歯髄炎（SIRP）の鑑別診断との関連性を探ることである．

BACKGROUND: According to the diagnosis criteria of the American Association of Endodontists (AAE), sensitive responses to cold and/or heat tests of suspected teeth compared with those of control teeth can be used for the diagnosis of pulpitis, but the role of electric pulp test (EPT) is not mentioned. It is believed that EPT has some limitations in determining the vitality of the pulp. The aim of this study was to explore the association between the difference in EPT values and the differential diagnoses of reversible pulpitis (RP) and symptomatic irreversible pulpitis (SIRP) caused by dental caries.

方法:

虫歯による歯髄炎の症例203例を対象とした．歯髄炎の診断は，AAEの診断基準に基づいて行った．患者の人口統計学的データと臨床検査データを収集した。疑いのある歯と対照歯のEPT値を測定し，両者の差を算出した．EPT値の差と歯髄炎の診断との相関関係を，単変量および多変量ロジスティック回帰を用いて解析した．

METHODS: A total of 203 cases with pulpitis caused by dental caries were included. A diagnosis of pulpitis was made on the basis of the diagnostic criteria of AAE. Patient demographic and clinical examination data were collected. The EPT values of the suspected teeth and control teeth were measured, and the differences between them were calculated. The correlation between the difference in the EPT values and diagnosis of pulpitis was analyzed using univariate and multivariate logistic regression.

結果:

203例（男性78例，女性125例，RP 115例，SIRP 88例，前歯部9例，前歯部59例，臼歯部135例）の患者の平均年齢は34.04±13.02（標準偏差）歳であった。統計解析には，未調整（粗）モデル，モデル1（年齢調整），モデル2（年齢・性別調整），モデル3（年齢・性別・歯種調整）を設定した。モデル3［オッズ比（OR）＝1.025；95％信頼区間（CI）1.002-1.050；P＝0.035］では，RPとSIRPの間のEPT値の差は統計的に有意であった。しかし、粗モデル、モデル1、モデル2、モデル3の予測確率の曲線下面積は、それぞれ0.565、0.570、0.585、0.617となり、モデルの精度が低いことがわかった。EPT値の差の傾向をカテゴリー変数で表したP値は、RPとSIRPを比較したEPT値の差は、統計的に有意ではないことを示した。

RESULTS: In the 203 cases (78 males and 125 females; 115 cases of RP, 88 cases of SIRP; 9 anterior teeth, 59 premolars, and 135 molars), the mean patient age was 34.04 ± 13.02 (standard deviation) years. The unadjusted (crude) model, model 1 (adjusted for age), model 2 (adjusted for age and sex), and model 3 (adjusted for age, sex, and tooth type) were established for the statistical analyses. In model 3 [odds ratio (OR) = 1.025; 95% confidence interval (CI) 1.002-1.050; P = 0.035], the difference in EPT values between RP and SIRP was statistically significant. However, the areas under the curve of predictive probability of the crude model, model 1, model 2, and model 3 were 0.565, 0.570, 0.585, and 0.617, respectively, showing that the model accuracy was low. The P-value for the trend in differences between the EPT values as a categorical variable showed that the differences in the EPT values, comparing RP and SIRP, were not statistically significant.

結論:

今回のデータに基づくと、EPT値の差はRPとSIRPを区別するのに十分ではなかった。

CONCLUSIONS: Based on the present data, the difference in EPT values was not sufficient to differentiate RP from SIRP.