Patterns of Vertical Root Fracture: Factors Affecting Stress Distribution in the Root Canal

Abstract

Previous studies have indicated that vertical root fracture tends to occur in a buccolingual direction, where dentin thickness is greatest. Factors potentially influencing the location and direction of root fracture include root canal shape, external root morphology, and dentin thickness. In this finite-element study, simulated root sections were varied systematically with respect to canal size and shape, external root morphology, and dentin thickness to determine their relative contribution to vertical root fracture. Similar models were constructed based on cross-sections of human tooth roots that had been fractured clinically or experimentally. Finite-element models demonstrated that canal curvature seems more important than external root morphology, in terms of stress concentration, and that reduced dentin thickness increases the magnitude but not the direction of maximum tensile stress. Models based on actual root fractures showed a strong similarity between tensile-stress distribution and fracture patterns.

Complex Apical Anatomy Revealed Following Endodontic Treatment of a Maxillary Molar Using the GentleWave System: A Case Report

“…After endodontic instrumentation, anatomical variations typically contain tissue remnants, bacteria, and dentin shavings that inhibit the ability of irrigation fluids to reach areas of the root canal system [41,42]. Additionally, over-enlargement or excess dentin removal from instrumentation can result in perforation, root fractures or other endodontic mishaps [12,43,45]. Therefore, the need for newer, more innovative technology to enhance cleaning and irrigation for endodontic therapy has only grown as the understanding of the true complexity of the naturally occurring root canal system is understood.…”

Effects of threaded post placement on strain and stress distribution of endodontically treated teeth

“…Stress concentration accounted for crack formation and propagation to the external surface of the root, resulting in root fracture. 24 SEM analysis showed cracks formed by post threading ( Figure 2D). These cracks started at the post thread end and coincided with stress concentration areas observed in the finite element analysis.…”

Minimum Access for Maximum Success

“…1) Failure of endodontic monoblock to reinforce the endodontically treated tooth [1] , 2) Intra coronal composite failed to strengthen the tooth [2] , 3)Placement of posts did not benefit molars [3] and 4) Many stress tests has proved the crack initiation in endodontically treated root [4,5] . Hence, for long term biological and functional integrity of root canal treated teeth there is a need to shift from traditional access to more conservative access.…”