Fracture Resistance of Endodontically Treated Premolars Reinforced with Ribbond Fibers and Prolene Mesh as Foundations: An In Vitro Study

ORIGINAL ReseARchThe incorporation of reinforcing fibers can significantly enhance the flexural strength, elastic modulus, and impact resistance of composite restorations.Various fibers have been explored, including glass, carbon, Kevlar, nylon, silica, and polyethylene. [8][9][10][11][12] Polypropylene fibers, such as those found in Prolene mesh, are thermoplastic polymers with a complex molecular structure.Although primarily used in surgical applications, they have potential in dentistry due to their mechanical durability. 13olypropylene fibers improve the flexural strength of composites, resist deformation, reduce polymerization shrinkage, and enhance IntroductIonFracture of endodontically treated teeth (ETT) remains a significant concern in restorative dentistry due to the structural compromise resulting from root canal treatment. 1Maxillary premolars are particularly susceptible to fractures, as they are situated along the curvature of the dental arch.Their position, angulation, and steep cuspal inclines contribute to increased fracture risk. 2 The extent of structural loss is directly correlated with reduced mechanical strength; approximately 20% of strength is lost with occlusal surface loss, and this increases to 46 or 63% with the loss of one or both marginal ridges, respectively. 3everal factors influence the fracture resistance of ETT, including the amount of remaining coronal tooth structure, presence and height of a ferrule, tooth position, crown type, postand-core design, and materials used. 4Restoration of endodontically treated premolars with appropriate techniques-such as crowns or fiber reinforcement-can reduce the risk of fracture. 5A thorough understanding of the biomechanical behavior of ETT is essential to ensure long-term success.Composite resin is widely used due to its compressive strength (250-400 MPa), making it suitable for restoring ETT.However, polymerization shrinkage may lead to microleakage. 6In high-stress posterior areas, alternatives like glass ionomer cement (GIC) and amalgam offer decent strength but fall short compared to composites and may wear or degrade under load.