破折した歯に歯冠片を再装着する際の接着強度に及ぼす保存環境の影響

Effect of storage environment on the bond strength of reattachment of crown fragments to fractured teeth.

抄録

目的:

本研究の目的は，残存歯に接着する前の歯冠片を保管する際の様々な保管環境を検討し，さらに修復歯を破折させるために必要な力を推定することである。

AIM: The aim of this study was to examine various storage environments for storing fragments before being bonded to the remaining teeth and also estimate the required force to fracture the restored teeth.

材料と方法:

下顎切歯60本を切歯部3分の1で破折させ、12本ずつ5つのグループに分け、通常の生理食塩水、水、牛乳、唾液、乾燥環境で24時間保管した。各グループの破折した部分はすべて，エッチ＆リンスボンディングシステムと流動性コンポジットレジンを用いて関連する頂部に接着した．破断耐性は万能試験機で測定し，結果は一元配置のANOVAとTukey統計検定を用いて分析した．

MATERIALS AND METHODS: Sixty mandibular incisor teeth were fractured on the incisal one-third and were divided into five groups of 12 each to be stored in normal saline, water, milk, saliva and dry environments for 24 hours. All the fractured parts in each group were bonded to their relevant apical parts by an etch and rinse bonding system and a flowable composite resin. The fracture resistance was measured by a universal testing machine, and the results were analyzed using one-way ANOVA and Tukey statistical tests.

結果:

その結果，5群間で統計的に有意な差が認められた（P<0.001）。Tukey検定では，牛乳と唾液の環境下で保管されたフラグメントの破壊に必要な力は，通常の生理食塩水，水，乾燥した環境下のものよりも有意に高いことが示された（P<0.05 ）。

RESULTS: The results revealed that the difference among the five groups was statistically significant (P<0.001). Tukey tests showed that the force required for fracturing fragments kept in the milk and saliva environments were significantly higher than those for the normal saline, water and dry environments (P<0.05 ).

おわりに:

乳液や唾液の環境下では，歯の破折に必要な力が他の環境よりも大きくなることが結論づけられた．

CONCLUSIONS: It was concluded that keeping the fractured parts in milk and saliva environments can increase the required force for fracturing teeth more than the other environments.