A three-dimensional finite element analysis of stress distribution in maxillary central incisor with a horizontal mid root fracture after various management protocols.

Context: The incidence of root fractures is about 1.2%-7% in permanent teeth and horizontal mid root fractures are most common in maxillary anteriors.

Aims: This study aims to evaluate the stress distribution in a maxillary central incisor with mid root fracture after various management protocols using three-dimensional finite element (FE) analysis.

Materials and methods: Four three dimensional FE models were constructed: Model 1-Normal tooth, Model 2-tooth with horizontal mid root fracture, Model 3-tooth with horizontal mid root fracture, coronal fragment filled with Biodentine, and access cavity sealed with composite resin cement and apical fragment left untreated and Model 4-tooth with horizontal mid root fracture restored with intraradicular fiber post as a splint and access cavity sealed with composite resin cement. The properties of materials were assigned and a force of 100 N was applied at 45° angle to the longitudinal axis of the tooth onto the palatal surface incisal to the cingulum.

Statistical analysis: Von-Mises stress along the length of the root analyzed and compared.

Results: The maximum stress distribution was observed at the palatal end of the coronal radicular fragment in both without treatment and with biodentine treatment. The stress distribution was concentrated more at the junction of the splinted area in the intraradicular fiber post splinted model.

Conclusions: The model with intraradicular fiber post as a splint exhibited more stress concentration at the splinted area due to bending forces. These stresses may adversely affect the healing around the fracture site and affect the longevity.