Canal Transportation and Centering Ability in Long Oval Canals: A Multidimentional Analysis.

INTRODUCTION: The purpose of this study was to evaluate and compare the centering ability and canal transportation of the ProTaper Next (PTN; Dentsply Maillefer, Ballaigues, Switzerland) and Self-adjusting File (SAF; ReDent-Nova, Ra'anana, Israel) systems in long oval root canals using cone-beam computed tomography imaging. METHODS: Fifty-six fully formed single-rooted mandibular premolars were selected with a buccolingual canal size 2 to 2.5 times the mesiodistal size at 5 mm from the apex, ranging from a 0°-10° canal curvature with a 5- to 6-mm radius. The teeth were divided into 2 groups (n = 28) and prepared with PTN or SAF according to the manufacturers' instructions. Cone-beam computed tomographic images were taken in the same position before and after instrumentation using modeling wax. The centering ability and canal transportation were calculated at 3, 6, and 9 mm from the apex in both mesiodistal and buccolingual directions. The mean and standard deviation were calculated, and the Student t test was used for comparative analysis. RESULTS: significant difference for canal transportation was observed mesiodistally at 9 mm from the apex (P < .05) where the PTN shaved more dentin in 1 direction. A significant difference for the centering ability was observed at 6 mm buccolingually from the apex (P < .05) where the PTN was less centered in the canal compared with the SAF. CONCLUSIONS: Both SAF and PTN were shown to be safe for being used in long oval canals. SAF resulted in less transportation at the coronal third in the mesiodistal direction and more centered at the middle third in the buccolingual direction compared with PTN.

Reliability of two different protocols used for intentional re-implantation of periodontally hopeless teeth.

Intentional re-implantation is the careful removal and re-insertion of an endodontically treated tooth performed with an attempt to preserve the natural dentition and patients' esthetic concerns. Its limited success rate and a possibility to obtain undesirable outcomes such as root resorption and ankylosis of the tooth restrict its clinical use to be attempted only as a last option after routine procedures. A vast array of procedures have been performed till date with inconsistent results due to lack of analogous protocols followed. Regardless of having a controversial background behind its success in periodontally compromised teeth, this procedure raises a hope to avoid unwarranted natural tooth loss. Performing each step with precision governs the success of the treatment. This case report demonstrates two different techniques with an interdisciplinary approach assessed over 1 year each.