Costa Scholz Maria Fernanda, Aboud Matos de Almeida Rossana, Scholz Nelson, Gomes Giovana M, Masson-P María José, Loguercio Alessandro D, Reis Alessandra, Bandéca Matheus C
Department of Restorative Dentistry, State University of Ponta Grossa, Paraná, Brazil.
The Post-Graduation Program in Dentistry, CEUMA University, São Luis, Maranhão, Brazil.
Clin Cosmet Investig Dent. 2020 Feb 26;12:61-70. doi: 10.2147/CCIDE.S230134. eCollection 2020.
When a phosphoric acid is used, before applying an adhesive system, it is known that obtaining an effective adhesion to the root canal walls is a challenge. The aim of the present study was to evaluate the influence of phosphoric acid viscosity and application mode on the push-out bond strength (BS) values of fiberglass post to root dentin. The conditioning pattern on the root dentin was also evaluated.
The roots of 44 endodontically treated premolars were divided into 4 groups, of eleven teeth each, according to the combination of the main factors: phosphoric acid viscosity (liquid or gel) and application mode (passive or sonic). After application of the two-step etch-and-rinse adhesive system, the fiberglass posts were cemented with a dual-cure resin-cement. Roots were sectioned transversely into six 1-mm slices for push-out BS test at 0.5 mm/min. Some roots of each group were selected for evaluation of the conditioning pattern by scanning electron microscopy. BS results (three-way ANOVA and Tukey's test) and the conditioning pattern (Kruskal-Wallis test and Mann-Whitney test) were statistically evaluated (α= 0.05).
The highest BS value was observed with a liquid phosphoric acid under sonic application mode (p < 0.05), being all other groups similar to one another (p < 0.05). Also, the highest BS value was observed in the cervical third, followed by the medium and the apical thirds (p < 0.05). The sonic application produced better smear layer removal and opening of dentinal tubules for both viscosities (p = 0.015).
A better bonding of fiberglass posts to root canals can be achieved when the post spaces are conditioned with a liquid phosphoric acid under sonic application.
当使用磷酸时，在应用粘结系统之前，已知要在根管壁上获得有效的粘结是一项挑战。本研究的目的是评估磷酸粘度和应用方式对玻璃纤维桩与根管牙本质的推出粘结强度（BS）值的影响。还评估了根管牙本质的预处理模式。
根据主要因素的组合，将44颗经根管治疗的前磨牙的牙根分为4组，每组11颗牙：磷酸粘度（液体或凝胶）和应用方式（被动或超声）。应用两步蚀刻冲洗粘结系统后，用双固化树脂水门汀粘结玻璃纤维桩。将牙根横向切成六个1毫米厚的切片，以0.5毫米/分钟的速度进行推出BS测试。每组选择一些牙根通过扫描电子显微镜评估预处理模式。对BS结果（三因素方差分析和Tukey检验）和预处理模式（Kruskal-Wallis检验和Mann-Whitney检验）进行统计学评估（α = 0.05）。
在超声应用模式下使用液体磷酸时观察到最高的BS值（p < 0.05），所有其他组彼此相似（p < 0.05）。此外，在颈部三分之一处观察到最高的BS值，其次是中部和根尖三分之一处（p < 0.05）。对于两种粘度，超声应用都能更好地去除玷污层并开放牙本质小管（p = 0.015）。
当用液体磷酸在超声应用下对桩间隙进行预处理时，可以实现玻璃纤维桩与根管更好的粘结。
