異なる接着戦略を用いたCAD/CAM材料の象牙質に対する微小引張接着強さ

Microtensile bond strength of CAD/CAM materials to dentin under different adhesive strategies.

抄録

本研究では，異なる接着ストラテジーを用いて，新しいコンピュータ支援設計/コンピュータ支援製造（CAD/CAM）修復材料の象牙質に対する微小引張接着強さ（μTBS）を評価することを目的とした．32本のクラウンをCAD/CAM材料（コントロールとしてVita Mark II、Vita Suprinity、Vita Enamic、Lava Ultimate）を用いて作製し、異なるレジンセメント（RelyX ARC、RelyX Unicem 2、RelyX Ultimate）を用いて象牙質に接着させた。標本は相対湿度100%の37℃で24時間保存し、切片化した。断面積約0.90 mm2の試料（n = 16）を、クロスヘッド速度0.5 mm/分の万能試験機でμTBS試験に供した。破壊モードを決定するため、サンプルをSEMで分析した。2元配置分散分析およびTukeyの検定（α=0.05）によると、交互作用効果（材料×合着戦略）は有意であった（p=0.001）。溶着ストラテジーに関係なく、Lava UltimateとVita Enamicで高いμTBSが得られ、Vita Mark IIとVita Suprinityとは有意差があった(p<0.05)。Vita Mark II、Vita Suprinity、Vita Enamic、Lava Ultimateでは、RelyX Unicem 2で得られたμTBSは、RelyX ARCまたはRelyX Ultimateで得られたμTBSと有意差はなかった。全グループで少なくとも3種類の破損が認められた。自己接着性レジンセメントを用いた接着戦略は、新しいCAD/CAM材料の象牙質への接着において、トータルエッチまたはセルフエッチ接着技術を用いた従来のレジンセメントと同等であった。

The present study aimed to evaluate the microtensile bond strength (μTBS) of novel computer-aided design/computer-aided manufacturing (CAD/CAM) restorative materials to dentin using different adhesive strategies. Thirty-two crowns were milled using CAD/CAM materials (Vita Mark II as control, Vita Suprinity, Vita Enamic and Lava Ultimate) and luted to dentin using different resin cements (RelyX ARC, RelyX Unicem 2 and RelyX Ultimate). The specimens were stored in 100% relative humidity at 37°C for 24 h and sectioned. The samples (n = 16) with cross-sectional areas of approximately 0.90 mm2, were submitted to a μTBS test in a universal testing machine with a crosshead speed of 0.5 mm/min. The samples were analyzed with SEM to determinate the failure mode. According to 2-way ANOVA and Tukey's test (α=0.05), the interaction effect (material x luting strategy) was significant (p=0.001). Regardless of the luting strategy, a higher μTBS was obtained with Lava Ultimate and Vita Enamic, which were significantly different from Vita Mark II and Vita Suprinity (p<0.05). For Vita Mark II, Vita Suprinity, Vita Enamic, and Lava Ultimate, the μTBS obtained with RelyX Unicem 2 was not significantly different from that obtained with RelyX ARC or RelyX Ultimate. All groups obtained at least three types of failure. The adhesive strategy with self-adhesive resin cement was comparable to conventional resin cement with total-etch or self-etch adhesive techniques in the bond of novel CAD/CAM materials to dentin.