EVALUATION OF FRACTURE RESISTANCE OF ENDODONTICALLY TREATED MAXILLARY TEETH RESTORED WITH FIBER POST AND RIBBOND WITH DIFFERENT POST SPACE DIAMETERS – AN IN-VITRO STUDY

Abstract: Background: Root canal posts are placed in teeth that have lost extensive tooth structure due to decay, failed fillings, or tooth fractures. The maxillary incisors are the most impacted teeth due to their anterior placement and protrusion resulting from the eruptive process. Traditionally, endodontically treated teeth are restored with a post-core and crown foundation system. The design, material, and modulus of elasticity of the dental posts are very important because they help hold the coronal restoration in place and keep it from breaking. Materials and Methods: A total of 30 samples were divided into two groups of 15 each. Group A consists of Fiber post and was subdivided into 3 subgroups based on post space preparation and the materials used are ParaCore(COLTENE) as core build-up, and ParaCore-SLOW(COLTENE) for luting of fiber post. Tenax(COLTENE) Fiber Post using 1.1mm, 1.3mm, 1.5mm diameter drills and their corresponding posts. Group B includes Ribbond which was subdivided based on post space preparation and materials used are Ribbond (Ribbond Inc., Seattle, WA, USA) 2mm width, wetting resin and securing composite. Peeso Reamers(MANI, Japan) No.#2,#3 are used for post-space preparation. Type I GIC(GC) was used for crown cementation. The fracture resistance was tested using an Instron Universal Testing Machine. The data was statistically analysed using one-way ANOVA and Post-Hoc Tukey's Test. Results: The one-way ANOVA showed a statistically significant difference. The highest mean fracture resistance in the fiber group was recorded for post space 1.1mm (593.20±7.04) and in the ribbond group, no post space preparation (283.76±7.51) had the highest mean fracture resistance. The post-hoc Tukey test was done for intra-group comparison of fiber post and ribbond post systems, where post space preparation with 1.1mm vs post space preparation with 1.5mm(447.90) for fiber post group and in ribbond group, no post space preparation vs post space preparation with peeso#3(191.67) showed the highest mean fracture resistance. Conclusion: This in-vitro study concluded that teeth restored with a 1.1mm fiber post exhibit greater fracture resistance compared to those restored with 1.3mm and 1.5mm posts and when comparing teeth restored using the Ribbond post system, those with no post space preparation demonstrated superior fracture resistance compared to those with minimal post space preparation, indicating that post space diameter influences the fracture resistance of endodontically treated maxillary teeth. Key Words: Fracture resistance, Fiber post, Ribbond, ParaCore, Post space diameter