Soares P V, Machado A C, Zeola L F, Souza P G, Galvão A M, Montes T C, Pereira A G, Reis B R, Coleman T A, Grippo J O
NCCL Research Group, Operative Dentistry and Dental Materials Department, School of Dentistry, Federal University of Uberlândia, Campus Umuarama, Uberlândia, Minas Gerais, Brazil.
Shaftsbury Medical Building, Shaftsbury, Vermont, USA.
Aust Dent J. 2015 Sep;60(3):309-16. doi: 10.1111/adj.12233.
The present study analysed the effects of different occlusal loading on premolars displaying various non-carious cervical lesions morphologies, restored (or not) with composites, by 3D finite element analysis.
A three-dimensional digital model of a maxillary premolar was generated using CAD software. Three non-carious cervical lesions morphological types were simulated: wedged-shaped, saucer and mixed. All virtual models underwent three loading types (100 N): vertical, buccal and palatal loading. The simulated non-carious cervical lesions morphologies were analysed with and without restorations to consider specific regions, such as the occlusal and gingival walls as well as the depth of the lesions. Data summarizing the stress distribution were obtained in MPa using Maximum Principal Stress.
Palatal loads were responsible for providing the highest values of accumulated tensile stress on the buccal wall; 27.66 MPa and 25.76 MPa for mixed and wedged-shaped morphologies, respectively. The highest tensile values found on non-carious cervical lesions morphologies restored with composite resin were 5.9 MPa in the mixed morphology, similar to those found on sound models despite their morphologies and occlusal loading.
The various non-carious cervical lesions morphologies had little effect on stress distribution patterns, whereas the loading type and presence of composite restorations influenced the biomechanical behaviour of the maxillary premolars.
本研究通过三维有限元分析，探讨了不同咬合负荷对呈现各种非龋性颈部病变形态、用复合树脂修复（或未修复）的前磨牙的影响。
使用CAD软件生成上颌前磨牙的三维数字模型。模拟三种非龋性颈部病变形态类型：楔形、碟形和混合型。所有虚拟模型均承受三种负荷类型（100 N）：垂直、颊向和腭向负荷。分析模拟的非龋性颈部病变形态在有修复和无修复情况下的特定区域，如咬合壁和牙龈壁以及病变深度。使用最大主应力以MPa为单位获得总结应力分布的数据。
腭向负荷导致颊壁上累积拉应力值最高；混合型和楔形形态分别为27.66 MPa和25.76 MPa。用复合树脂修复的非龋性颈部病变形态上发现的最高拉应力值在混合型中为5.9 MPa，与健康模型上发现的值相似，尽管它们的形态和咬合负荷不同。
各种非龋性颈部病变形态对应力分布模式影响较小，而负荷类型和复合树脂修复的存在影响上颌前磨牙的生物力学行为。
