糖尿病が歯根の微小硬度に及ぼす影響．In-vitro Study（生体内試験）

Diabetes Mellitus Affects the Microhardness of Root Dentine: An in-vitro Study.

抄録

目的:

本研究は、糖尿病患者と非糖尿病患者の歯牙を採取し、異なる根管洗浄液を塗布して根面硬度と侵襲感受性を比較することを目的としたものである。

OBJECTIVE: This study was undertaken to compare microhardness and erosion susceptibility of root dentine in teeth extracted from diabetic and non-diabetic donors after the application of different root canal irrigants.

方法:

単根小臼歯48本（糖尿病患者，非糖尿病患者各24本）を選択し，回転式プロテーパーファイルで根管形成を行った．中根3分の1から4 mmの象牙質スライスを横方向に切り出した．4つのサブグループ（n=6）に分け，5分間の潅流を行った．1）2.6%次亜塩素酸ナトリウム（NaOCl），2）17%エチレンジアミン四酢酸（EDTA），3）2%クロルヘキシジン（CHX），4）通常生理食塩水である．表面硬度は，歯髄-歯槽骨界面から100 μmおよび500 μmの深さで測定した．走査型電子顕微鏡（SEM）を用いて，象牙質侵食の程度を判定した．データは，二元配置分散分析，Tukeyのポストホックテスト，およびカイ二乗検定を用いて解析した（P<0.05）．

METHODS: Forty-eight single-rooted premolars with single canals (24 each from diabetic and non-diabetic) were selected, and root canals were shaped by using rotary ProTaper files. Dentine slices of 4 mm were transversely sectioned from the middle root third. Specimens were assigned to four subgroups (n=6) and irrigated for 5 minutes: 1) 2.6% sodium hypochlorite (NaOCl); 2) 17% ethylenediaminetetraacetic acid (EDTA); 3) 2% chlorhexidine (CHX); and 4) normal saline. Surface microhardness was determined at 100- and 500-µm depths from the pulp-dentine interface. Scanning electron microscope (SEM) was used to determine the severity of dentine erosion. Data were analyzed by using two-way ANOVA, Post-hoc Tukey's, and Chi-square tests (P<0.05).

結果:

糖尿病，NaOCl，EDTAは，歯質表面の微小硬度を有意に低下させた（P＜0.05）．糖尿病は，象牙質の侵食感受性にほとんど影響を及ぼさなかった（P>0.05）．

RESULTS: Diabetes as well as NaOCl and EDTA decreased surface microhardness of dentine significantly (P<0.05). Diabetes had little effect on the erosion susceptibility of dentine (P>0.05).

結論:

根管洗浄液の微小硬度は，特に糖尿病患者において有意に低下し，根管治療歯の寿命に影響を与える因子である可能性が示唆された．

CONCLUSION: Root canal irrigants can significantly lower the microhardness; specifically, in diabetic patients, and may be a factor affecting the longevity of root canal-treated teeth.