Department of Restorative Dentistry, State University of Ponta Grossa, Ponta Grossa, Parana, Brazil; Department of Dental Clinical Sciences, Dalhousie University, Faculty of Dentistry, Halifax, Nova Scotia, Canada.
Department of Dental Clinical Sciences, Dalhousie University, Faculty of Dentistry, Halifax, Nova Scotia, Canada.
Dent Mater. 2023 Mar;39(3):275-292. doi: 10.1016/j.dental.2023.01.007. Epub 2023 Mar 1.
This study investigated the ability of a laser, and a 'quad-wave' LCU, to photo-cure paste and flowable bulk-fill resin-based composites (RBCs).
Five LCUs and nine exposure conditions were used. The laser LCU (Monet) used for 1 s and 3 s, the quad-wave LCU (PinkWave) used for 3 s in the Boost and 20 s in the Standard modes, the the multi-peak LCU (Valo X) used for 5 s in the Xtra and 20 s in the Standard modes, were compared to the polywave PowerCure used in the 3 s mode and for 20 s in the Standard mode, and to the mono-peak SmartLite Pro used for 20 s. Two paste consistency bulk-fill RBCs: Filtek One Bulk Fill Shade A2 (3 M), Tetric PowerFill Shade IVA (Ivoclar Vivadent), and two flowable RBCs: Filtek Bulk Fill Flowable Shade A2 (3 M), Tetric PowerFlow Shade IVA (Ivoclar Vivadent) were photo-cured in 4-mm deep x 4-mm diameter metal molds. The light received by these specimens was measured using a spectrometer (Flame-T, Ocean Insight), and the radiant exposure delivered to the top surface of the RBCs was mapped. The immediate degree of conversion (DC) at the bottom, and the 24-hour Vickers Hardness (VH) at the top and bottom of the RBCs were measured and compared.
The irradiance received by the 4-mm diameter specimens ranged from 1035 mW/cm (SmartLite Pro) to 5303 mW/cm (Monet). The radiant exposures between 350 and 500 nm delivered to the top surface of the RBCs ranged from 5.3 J/cm (Monet in 1 s) to 26.4 J/cm (Valo X), although the PinkWave delivered 32.1 J/cm in 20 s 350 to 900 nm. All four RBCs achieved their maximum DC and VH values at the bottom when photo-cured for 20 s. The Monet used for 1 s and the PinkWave used for 3 s on the Boost setting delivered the lowest radiant exposures between 420 and 500 nm (5.3 J/cm and 3.5 J/cm respectively), and they produced the lowest DC and VH values.
Despite delivering a high irradiance, the short 1 or 3-s exposures delivered less energy to the RBC than 20-s exposures from LCUs that deliver> 1000 mW/cm. There was an excellent linear correlation (r > 0.98) between the DC and the VH at the bottom. There was a logarithmic relationship between the DC and the radiant exposure (Pearson's r = 0.87-97) and between the VH and the radiant exposure (Pearson's r = 0.92-0.96) delivered in the 420-500 nm range.
本研究考察了激光和“四波” LCU 对糊剂和流动性块状填充树脂基复合材料(RBC)的光固化能力。
使用了五种 LCU 和九种曝光条件。使用激光 LCU(Monet)进行 1 s 和 3 s,四波 LCU(PinkWave)在 Boost 模式下使用 3 s,在 Standard 模式下使用 20 s,多峰 LCU(Valo X)在 Xtra 模式下使用 5 s,在 Standard 模式下使用 20 s,与多波 PowerCure 进行比较,后者在 3 s 模式下使用,在 Standard 模式下使用 20 s,与单峰 SmartLite Pro 进行比较,后者使用 20 s。两种糊剂稠度块状填充 RBC:Filtek One Bulk Fill Shade A2(3M),Tetric PowerFill Shade IVA(Ivoclar Vivadent),以及两种流动性 RBC:Filtek Bulk Fill Flowable Shade A2(3M),Tetric PowerFlow Shade IVA(Ivoclar Vivadent),在 4-mm 深 x 4-mm 直径的金属模具中光固化。使用分光光度计(Flame-T,Ocean Insight)测量这些样本接收到的光,并绘制 RBC 顶部的辐照暴露量图。测量并比较 RBC 底部的即时转化率(DC)和 24 小时维氏硬度(VH)的顶部和底部。
直径为 4mm 的样本接收到的辐照度范围为 1035 mW/cm(SmartLite Pro)至 5303 mW/cm(Monet)。在 350 至 500nm 范围内输送到 RBC 顶部的辐照量范围为 5.3 J/cm(Monet 在 1 s 时)至 26.4 J/cm(Valo X),尽管 PinkWave 在 350 至 900nm 范围内输送了 32.1 J/cm 的 20 s。当使用 20 s 光固化时,所有四种 RBC 都在底部达到最大的 DC 和 VH 值。Monet 在 1 s 时和 PinkWave 在 Boost 设置下使用 3 s 时,在 420 至 500nm 范围内输送的辐照量最低(分别为 5.3 J/cm 和 3.5 J/cm),并且产生的 DC 和 VH 值最低。
尽管提供了高辐照度,但 1 秒或 3 秒的短时间曝光向 RBC 输送的能量比输送>1000 mW/cm 的 LCU 的 20 秒曝光输送的能量少。在底部,DC 和 VH 之间存在极好的线性相关性(r>0.98)。在 420 至 500nm 范围内,DC 和辐照量(Pearson r=0.87-0.97)以及 VH 和辐照量(Pearson r=0.92-0.96)之间存在对数关系。