Baldi Andrea, Rossi Tommaso, Comba Allegra, Vergano Edoardo Alberto, Montrella Roberta, Pampaloni Benedetta, Chiecchio Valeria, Rolando Chiara, Scotti Nicola
Dental School of Turin, Department of Surgical Sciences, Via Nizza 230, Turin, 10100, Italy.
BMC Oral Health. 2025 Apr 23;25(1):619. doi: 10.1186/s12903-025-05970-y.
Despite improvements in adhesive systems and restorative materials, interfacial gap opening and subsequent microleakage are major factors in the failure of resin-based composite (RBC) restorations. This study evaluated the marginal gap in class V restorations using two highly-filled flowable RBC with varying viscosities, both before and after aging process.
Standardized class V cavities were created on the buccal side of intact single-root human upper premolars (n = 48). Specimens were randomly divided into three groups (n = 16) considering the selected restorative materials: a nanohybrid packable RBC serving as a control group (G1, Clearfil Majesty ES2, Kuraray Noritake) and two highly-filled RBCs with different viscosities (G2, Majesty ES Low Flow, Kuraray Noritake; G3, Majesty ES Super Low Flow, Kuraray Noritake). The initial marginal adaptation, both at the enamel and dentin substrate, was evaluated using optical coherence tomography (OCT). Specimens were then divided into two subgroups (n = 8) according to the aging process performed: thermocycling (TC) and thermomechanical cycling (TMC). After TC and TMC specimens were scanned again with OCT to evaluate margin degradation. Using a dedicated program, 2D cross-sectional images were obtained and the images were processed and quantitatively analyzed using Image J software. The interfacial gap between tooth and composite was linearly measured at baseline and after aging. A three-way analysis of variance (ANOVA) and a post-hoc Tuckey test were used to statistically analyze the data (Stata 17.0 software package).
ANOVA statistics regarding baseline and post aging results indicated that the employed material and the substrate were influent on interfacial gap (p ≤ 0.05). The ANOVA test also showed that TMC induce significantly higher gap opening than the TC. G2 (Majesty ES Low Flow) performed significantly better than G1 (Clearfil Majesty ES2) and G3 (Majesty ES Super Low Flow) at baseline and then G1(Clearfil Majesty ES2) after the aging process in terms of interfacial adaptation. Dentin showed significantly lower adaptation at both the baseline and post aging process. Moreover, the thermomechanical cycling induced a significantly higher gap opening than the thermocycling alone.
Highly-filled flowable RBC showed promising results in terms of interfacial gap adaptation both at the baseline and after the aging process. The presence of a cervical substrate and the mechanical aging worsen the marginal adaptation.
尽管粘结系统和修复材料有所改进，但界面间隙的形成及随后的微渗漏仍是树脂基复合材料（RBC）修复失败的主要因素。本研究评估了两类不同粘度的高填料可流动RBC在V类洞修复中老化前后的边缘间隙。
在完整的单根人上颌前磨牙颊侧制备标准化V类洞（n = 48）。根据所选修复材料将样本随机分为三组（n = 16）：一组纳米混合可压实RBC作为对照组（G1，Clearfil Majesty ES2，可乐丽诺瑞特），以及两种不同粘度的高填料RBC（G2，Majesty ES Low Flow，可乐丽诺瑞特；G3，Majesty ES Super Low Flow，可乐丽诺瑞特）。使用光学相干断层扫描（OCT）评估牙釉质和牙本质基底处的初始边缘适应性。然后根据进行的老化过程将样本分为两个亚组（n = 8）：热循环（TC）和热机械循环（TMC）。在TC和TMC后，再次用OCT扫描样本以评估边缘降解情况。使用专用程序获取二维横截面图像，并使用Image J软件对图像进行处理和定量分析。在基线和老化后线性测量牙齿与复合材料之间的界面间隙。采用三因素方差分析（ANOVA）和事后Tuckey检验对数据进行统计学分析（Stata 17.0软件包）。
关于基线和老化后结果的ANOVA统计表明，所用材料和基底对界面间隙有影响（p≤0.05）。ANOVA检验还表明，TMC比TC引起的间隙开口明显更大。在基线时，G2（Majesty ES Low Flow）在界面适应性方面明显优于G1（Clearfil Majesty ES2）和G3（Majesty ES Super Low Flow），而在老化后G1（Clearfil Majesty ES2）表现更好。牙本质在基线和老化后过程中的适应性均明显较低。此外，热机械循环比单独的热循环引起的间隙开口明显更大。
高填料可流动RBC在基线和老化后过程中的界面间隙适应性方面显示出良好的结果。颈部基底的存在和机械老化会使边缘适应性变差。
