Comparison of Fracture Resistance of Endodontically Treated Teeth With Traditional Endodontic Access Cavity, Conservative Endodontic Access Cavity, Truss Endodontic Access Cavity, and Ninja Endodontic Access Cavity Designs: An In Vitro Study

Abstract

Introduction: Endodontic access cavity preparation plays a vital role as preservation of enamel structure is of utmost importance for a tooth's strength to be maintained. As teeth become fragile after a root canal therapy, this study was designed to compare in vitro the fracture resistance of root-filled and restored teeth with traditional endodontic access cavity, conservative endodontic access cavity (CEC), ninja endodontic access cavity (NEC), and truss endodontic access cavity (TEC).Materials and methods: Control (intact teeth) and traditional endodontic access cavity as well as CEC, NEC, and TEC groups were each given a new human mandibular molar that was freshly removed. Cone beam computed tomography (CBCT) scans of the cone beam showed the values of CEC, NEC, and TEC. After that the teeth were endodontically treated and repaired. To test the specimens, universal testing equipment was used. In order to avoid tooth breakage, the maximum load was determined. Statistical analysis was used in the form of Kolmogorov-Smirnov and Levene tests, which were used to examine data for typical dispersion and consistency in change.Results: Intact teeth showed the highest resistance to fracture compared with other groups. TEC showed significantly higher resistance to fracture compared to the CEC design.Conclusions: It is possible, within the restrictions of this research, to infer that the TEC design enhanced tooth fracture strength in comparison with the CEC design.

Fracture Resistance of Endodontically Treated Premolars with Different Access Preparations and Coronal Cavity Designs – An In Vitro Study

“…And others who found that remaining tooth structure and wall thickness is an effective clinical parameter in selecting an appropriate adhesive restoration technique for endodontically treated premolars (30,31) . Such superior strength may be due to the preservation of teeth structure whether axial walls or even partial conservation of the roof of the pulp chamber, which may play a major role in binding the walls of the cavity, making them more resistance to unfavorable deformation during function (13) .On the other hand, the findings of our study was in contradiction with Forster et al who found that wall thickness didn't affect fracture strength in teeth restored with a direct resin composite (32) .…”

“…Several modifications of traditional endodontic access cavity preparation were developed to prevent excessive removal of tooth structure, that was done to create wider passage for proper biomechanical preparation of the root canal, such modifications are: conservative endodontic access cavity, orifice-directed dentin conservation access cavity (Truss), ultra conservative access cavity (Ninja), caries driven, restorative driven, Cala lilly enamel preparation, image guided endodontic access, dynamically guided endodontic access and micro guided endodontic access (6) . Reducing tooth structure removal, protecting the pericervical dentin and a part of the chamber floor, favoring survival and function of endodontically treated teeth (13) .…”

The Effect of Restoration of Endodontically Treated Teeth with Different Restorations in Both Modern and Traditional Access Cavity Preparations

“…These findings were consistent with previous studies that proved that dentin protection is achieved by reducing the cavity size which consequently increases tooth break resistance. (26,27) On the other hand, in intra Group I comparison, the effect of material strengths was significantly shown due to significant amount of loss of tooth structure by the traditional access cavity preparation and traditional Endo-Crown preparation which showed that lithium disilicate is almost double the strength of composite milled and triple the strengths of 3D printed composite. The result coincides with other studies that show lower fracture resistance of endodontically treated teeth following traditional access cavity preparation regardless the type of restoration material used.…”

Effect of fiber-reinforced direct restorative materials on the fracture resistance of endodontically treated mandibular molars restored with a conservative endodontic cavity design

“…For the distal canal, a truss endodontic access cavity design is used to provide direct access from the occlusal surface) [ 17 , 18 ]. A recent study showed that a truss endodontic access cavity could increase the fracture strength of endodontically treated teeth compared with other conservative endodontic cavity designs and traditional endodontic access cavity design [ 4 ].…”