采用大块充填复合树脂和分层充填技术修复磨牙的力学性能、收缩应力、牙尖应变及抗折性能

Mechanical properties, shrinkage stress, cuspal strain and fracture resistance of molars restored with bulk-fill composites and incremental filling technique.

作者信息

Rosatto C M P, Bicalho A A, Veríssimo C, Bragança G F, Rodrigues M P, Tantbirojn D, Versluis A, Soares C J

机构信息

Department of Operative Dentistry and Dental Materials, Dental School, Federal University of Uberlândia, Uberlândia, Minas Gerais, Brazil.

Department of Restorative Dentistry, College of Dentistry, University of Tennessee Health Science Center, Memphis, TN, USA.

出版信息

J Dent. 2015 Dec;43(12):1519-28. doi: 10.1016/j.jdent.2015.09.007. Epub 2015 Oct 9.

DOI:10.1016/j.jdent.2015.09.007

PMID:26449641

Abstract

OBJECTIVES

To compare bulk-fill with incremental filling techniques for restoring large mesio-occlusal-distal (MOD) restorations.

METHODS

Seventy-five molars with MOD preparations were divided into five groups: Z350XT, incrementally filled with Filtek Z350XT and four bulk-fills-FBF/Z350XT, Filtek Bulk Fill/Filtek Z350XT; VBF/CHA, Venus Bulk Fill/Charisma Diamond; SDR/EST-X, SDR/Esthet-X HD; TEC, TetricEvoCeram Bulk Fill. Cuspal strains were measured using strain-gauges (n=10): CSt-Re, during restorative procedure; CSt-100N, during 100N occlusal loading; CSt-Fr, at fracture load. Before fracture load, teeth were load-cycled. Fracture resistance, fracture mode, and enamel cracks were recorded. The other five teeth were used for Elastic modulus (E) and Vickers hardness (VH). Post-gel shrinkage (Shr), diametral tensile strength (DTS) and compressive strength (CS) were determined (n=10). Shrinkage stresses were analyzed using finite element analysis.

RESULTS

SDR had similar CS values as TEC, lower than all other composites. CHA had similar DTS values as Z350XT, higher than all other composites. Z350XT had the highest mean Shr and SDR the lowest Shr. New enamel cracks and propagation was observed after the restoration, regardless of filling technique. Z350XT had lower fracture resistance than bulk-fill composite techniques. No significant differences in failure modes were found. E and VH were constant through the depth for all techniques. Bulk-filling techniques had lower stresses compared to Z350XT.

CONCLUSIONS

Flowable bulk-fill composites had lower mechanical properties than paste bulk-fill and conventional composites. All bulk-fill composites had lower post-gel shrinkage than conventional composite. Bulk-fill filling techniques resulted in lower cusp strain, shrinkage stress and higher fracture resistance.

CLINICAL SIGNIFICANCE

Using bulk-fill composites cause lower CSt wich indicates lower stress in restored tooth. Furthermore, bulk-fill composites have a higher fracture resistance. Therefore, clinicians may choose the bulk-fill composite to decrease undesirable effects of restoration while simplifying filling procedure.

摘要

目的

比较用于修复大的近中-咬合-远中（MOD）修复体的整块充填技术和分层充填技术。

方法

将75颗有MOD预备体的磨牙分为五组：Z350XT组，用Filtek Z350XT进行分层充填；以及四种整块充填材料组——FBF/Z350XT组，Filtek Bulk Fill/Filtek Z350XT；VBF/CHA组，Venus Bulk Fill/Charisma Diamond；SDR/EST-X组，SDR/Esthet-X HD；TEC组，TetricEvoCeram Bulk Fill。使用应变片测量牙尖应变（n = 10）：CSt-Re，在修复过程中；CSt-100N，在100N咬合加载过程中；CSt-Fr，在断裂载荷时。在断裂载荷之前，对牙齿进行加载循环。记录抗折强度、断裂模式和釉质裂纹。另外五颗牙齿用于测量弹性模量（E）和维氏硬度（VH）。测定凝胶后收缩率（Shr）、径向拉伸强度（DTS）和抗压强度（CS）（n = 10）。使用有限元分析来分析收缩应力。

结果

SDR的抗压强度值与TEC相似，低于所有其他复合材料。CHA的径向拉伸强度值与Z350XT相似，高于所有其他复合材料。Z350XT的平均凝胶后收缩率最高，SDR的最低。无论充填技术如何，修复后均观察到新的釉质裂纹和扩展。Z350XT的抗折强度低于整块充填复合材料技术。在失败模式方面未发现显著差异。所有技术的E和VH在整个深度上都是恒定的。与Z350XT相比，整块充填技术的应力更低。