Invasive cervical root resorption(ICR) is an insidious and aggressive form of external root resorption that damages the periodontium. The potential predisposing factors of ICR are orthodontics, dental trauma, intracoronal bleaching, delayed eruption, surgery involving cement enamel junction(CEJ), bruxism, developmental defect and deep root scaling. According to Heithersay, ICR is classified as Class1: A small invasive resorption lesion near the cervical area with shallow penetration into the dentin. Class2: A well defined invasive resorptive lesion that has penetrated close to the coronal pulpal chamber but shows little or no extension into the radicular dentin. Class3: A deeper invasion of dentin by resorbing tissue, not only involving the coronal dentin but also extending atleast to the coronal third of the root. Class4: A large invasive resorptive process that has extended beyond the coronal third of the root canal.
Clinically ICR presents with a pink spot next to cervical margin and radiographically as a single resorption cavity which penetrates the tooth through small denuded areas. It spreads within the radicular dentin and does not directly penetrate the pulp due to protective predentin, but rather spread around the root canal. With time, it may involve pulp. The basic aim of the treatment of ICR is to inactivate all active resorbing tissue by nonsurgical or surgical approach and restoration with suitable restorative material. Various adhesive materials can be used for restoration of these ICR cavities such as CGIC(conventional glass ionomer cement) , RMGIC(resin modified glass ionomer cement), FC(flowable resin composite), amalgam, MTA, giomer to enhance the resistance to fracture of endodontically treated teeth by bonding to weakened tooth structure. Endodontically treated teeth tend to be weaker than sound teeth due to loss of eihter coronal or radicular tooth structure as a result of endodontic treatment that may result in fracture on functional loading. The objectiveof the study was to compare the fracture resistance of endodontically treated teeth with simulated ICR cavities when restored with different adhesive restorative materials namely CGIC, RMGIC, FC and Giomer. The null hypothesis tested is there is no difference in the fracture resistance of endodontically treated teeth with simulated ICR cavities restored with different adhesive restorative materials.
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