INVITRO EVALUATION OF FRACTURE RESISTANCE OF PREFABRICATED SINGLE AND DOUBLE UNIT POST AND CORE SYSTEMS IN MAXILLARY ANTERIOR TEETH.

*Mohammad Raheem, Dr. Girija S. Sajjan, MDS, Dr. D. Praveen, MDS, Dr. Madhu Varma K., Dr. Nanda Kishore Kode and Dr. M. Srikrishnateja

ABSTRACT

The fracture resistance of post-endodontic restorations with prefabricated post depends on their ability to resist masticatory load. The double unit prefabricated post and core system involves, placement of rigid post and, core build-up with less rigid material. Concentration of high stress is observed in transitional area between a rigid and a less rigid material leading to failure. Recently a prefabricated post and core system with a single material is available. The study evaluated the fracture resistance and mode of failures of single and double unit post and core systems. Methods: Decoronation of 44 human extracted maxillary central incisors was done at a level 2mm incisal to cementoenamel junction. The samples were instrumented with rotary Pro Taper universal system. Sectional obturations were done and randomly divided into two groups. Group I: Double unit post and core. (D.T. Light- Post X-RO)(BISCO) Group II: Single unit post and core. (Edelweiss Post and Core system). The samples were subjected to constant load under a Universal testing machine. Data were subjected to Independent t test for Statistical analysis. The mode of failures of both post and core systems were evaluated under Stereomicroscope. Results: The Mean values of fracture resistance of Group I & II were 420.54 & 289.17 N, respectively. In Group I, 77% of the fractures were favourable. In Group II, 95% of the fractures were favourable. Conclusion: Both systems presented sufficient fracture resistance. D.T. Light group showed better performance compared to Edelweiss group. Edelweiss group showed more favourable fractures compared to D.T. Light post group.

Keywords: Edelweiss, Fracture Resistance, Postendodontic restoration, prefabricated post.