Assess, using finite element analysis, the adhesive behavior of Class I restorations under physiological occlusal loads on an endodontically treated first upper premolar with conventional and conservative crown opening surrounded by alveolar bone in normal and osteoporotic conditions. For this, four virtual models were used: M1-conservative access/normal bone; M2-conventional access/normal bone; M3-conservative access/osteoporotic bone; M4-conventional access/osteoporotic bone. On enamel, under axial load, the highest peaks occurred on conventional models and, under oblique load, the highest peaks occurred on conservative opening models. The bone condition showed no influence on the adhesive behavior. On dentin, under axial load, the models showed similar behaviors, regardless of the bone condition; under oblique load, the highest incidence of forces occurred on the distal region of the palatal root canal entrance and the highest peak was observed in the conventional opening model with normal bone. Also, under oblique load, conventional opening models showed larger values on dentin for the normal bone and similar for the osteoporotic. The conclusions shows higher displacement tensile strength peaks were observed in the conventional models, which can lead to a greater risk of adhesive failure on class I restorations with this opening. Therefore, a conservative opening would be recommended to avoid opening clinical complications. The bone condition showed no significant influence on adhesive behavior, except for dentin under oblique load, where conventional models showed larger values relative to normal bone and similar to the osteoporotic bone.

中文翻译：

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通过有限元分析，保守牙髓入路和骨质疏松骨对修复材料粘附行为的影响。

使用有限元分析，评估在正常咬合和骨质疏松情况下，经牙髓治疗的第一个上颌前磨牙的常规咬合牙冠开口周围被牙槽骨包围的生理性咬合负荷下，I类修复物的黏附行为。为此，使用了四个虚拟模型：M1保守通道/正常骨骼；M2-常规通路/正常骨骼；M3保守通路/骨质疏松骨；M4传统通路/骨质疏松骨。在搪瓷上，在轴向载荷下，常规模型的峰值最大，而在倾斜载荷下，保守型开放模型的峰值最大。骨骼状况未显示对粘合行为的影响。在牙本质上，在轴向载荷下，无论骨骼状况如何，模型都表现出相似的行为。在斜载荷下 力的最大发生发生在pa根管入口的远端区域，并且在具有正常骨骼的传统开放模型中观察到了最大的峰值。同样，在倾斜载荷下，常规的开放模型对正常骨骼的牙本质显示较大的值，而对骨质疏松模型的相似。结论表明，在常规模型中观察到较高的位移抗拉强度峰值，这可能导致通过该开口在I类修复体上发生粘合失败的更大风险。因此，建议保守性开放以避免开放性临床并发症。除了在倾斜载荷下的牙本质（常规模型相对于正常骨骼具有更大的值且与骨质疏松性骨骼相似）之外，牙本质对黏附行为没有明显影响。