Fracture Resistance Evaluation After Minimal Invasive Preparation Using Trunatomy Versus Protaper Next (A Comparative in Vitro Study)

Abstract

INTRODUCTION:Minimally invasive endodontics (MIE) is the latest innovation in endodontics that focuses on minimal mechanical preparation; as it leads to preserving the fracture strength of teeth. AIM OF THE STUDY:To compare the fracture resistance of mandibular molars following preparation by TruNatomy versus ProTaper Next rotary instruments. MATERIALS AND METHODS: Thirty permanent mandibular molars were selected in this study. Teeth were randomly distributed into two equal groups. Decoronation of the crown was done and the distal root was sectioned from the mesial root and acted as a control group. Study Group I: Fifteen mesial roots (MB and ML canals) were prepared using TruNatomy (TRN) rotary files up to the prime file (26/.04). Study Group II: Fifteen mesial roots were prepared using ProTaper Next (PTN) rotary files to size X3(30/.07). Control Group: The distal root of each tooth. Roots were placed in acrylic resin blocks and fracture loading was applied. Data were statistically analyzed. RESULTS: Roots prepared with TRN were significantly more fracture resistant than roots prepared with PTN. In addition, a significant difference was noted between the mesial and distal roots within each group. CONCLUSIONS: Mandibular molar mesial roots prepared with TRN rotary files (26/.04) are significantly more fracture resistant than those prepared with PTN rotary files (30/.07). In addition, intact mandibular molar distal roots were significantly less prone to fracture than the mesial roots prepared with both systems.