Finite element analysis of the influence of different proximal and distal dental defects on the restoration of mandibular first molar after root canal treatment
Objective To compare the residual dental tissue and stress distribution of the mandibular first molar with different proximal and distal tooth defects after root canal treatment.Methods The finite element method was used to model the restorations of mandibular first molars with different mesiodistal tooth defects,and divided into the fully covered high embedding with less proximal and distal dental tissue group(Group A1),the fully covered high embedding with more proximal and distal dental tissue group(Group A2),the medullary cavity fixed crown with less proximal and distal dental tissue group(Group B1),and the medullary cavity fixed crown with more proximal and di-stal dental tissue group(Group B2).The vertical and oblique loads were applied to record the stress magnitude and distribution of the restorations,the crown tissues,the interfaces between the restorations and the tooth tissues in dif-ferent restorative forms under the two loading modes.Results Under the vertical loading mode,the equivalent stress(EQV)of restorations were concentrated around the loading point,there were no differences between the four groups.The EQV of crown tissues were similarly distributed,with small differences in the peaks.The EQV stress distribution of the restoration-tooth structure interface was different,A1,A2 groups concentrated at the line angle of the bottom wall and the axial wall,while B1,B2 groups concentrated near the loading point,and the peak value of A1,A2 groups was higher than those of B1,B2 groups.Under the oblique loading mode,the EQV of restoration were concentrated around the loading point,the peaks of A1,A2 Group were higher than those of B1,B2 Group.The EQV distribution of crown tissue varied,the peaks of Group A1＞A2＞B1＞B2,the EQVdistribution of the restorative-tissue in-terface varied,the peaks of Group A1＞A2＞B1＞B2.Conclusions Compared with full overlays,pulp cavity re-taining crowns can effectively reduce the residual tissue stress and the possibility of crown fracture.
Three-dimensional finite element analysisEquivalent stressRestorationsMandibular first molarRoot canal therapy
万方数据
维普
