Aim:The aim of the present study was to compare the canal transportation and centering ability of Rotary ProTaper, One Shape and Wave One systems using cone beam computed tomography (CBCT) in curved root canals to find better instrumentation technique for maintaining root canal geometry.Materials and Methods:Total 30 freshly extracted premolars having curved root canals with at least 10 degrees of curvature were divided into three groups of 10 teeth each. All teeth were scanned by CBCT to determine the root canal shape before instrumentation. In Group 1, the canals were prepared with Rotary ProTaper files, in Group 2 the canals were prepared with One Shape files and in Group 3 canals were prepared with Wave One files. After preparation, post-instrumentation scan was performed. Pre-instrumentation and post-instrumentation images were obtained at three levels, 3 mm apical, 3 mm coronal and 8 mm apical above the apical foramen were compared using CBCT software. Amount of transportation and centering ability were assessed. The three groups were statistically compared with analysis of variance and Tukey honestly significant.Results:All instruments maintained the original canal curvature with significant differences between the different files. Data suggested that Wave One files presented the best outcomes for both the variables evaluated. Wave One files caused lesser transportation and remained better centered in the canal than One Shape and Rotary ProTaper files.Conclusion:The canal preparation with Wave One files showed lesser transportation and better centering ability than One Shape and ProTaper.

Introduction. Single-step apexification procedures using mineral trioxide aggregate (MTA) have been reported as favorable treatment options for teeth with an open apex, posing greater benefits compared to the other available medicaments. However, controlled apical placement of MTA is a challenging procedure to perform using orthograde approach. This case series describes the outcome of the unintentional extrusion of MTA into periradicular tissues during apexification, in three separate cases. Methods. Three adult patients reported to the Department of Conservative Dentistry and Endodontics for the management of maxillary incisors with open apices. After isolation, conventional access, and cleaning and shaping procedures, one-step MTA apexification was performed. On subsequent radiographs, a considerable amount of MTA was seen to be extruded in all the three cases. Results. During follow-up examination the teeth were seen to be asymptomatic in all cases and radiographically demonstrated repair of the periapical lesion. Conclusion. The results of these cases suggest that extrusion of MTA into the periapical tissues does not cause any detrimental effect, which could be attributed to the biologic properties of MTA.

ABSTRACT:Maxillary midline diastema is a common esthetic problem in mixed and permanent dentition. The space can occur either as a transient malocclusion or created by developmental, pathological or iatrogenic factors. Many innovative therapies are available from restorative procedures such as composite build-up to surgery (frenectomies) and Orthodontics is available. Treatment depends upon the correct diagnosis of its etiology and early intervention relevant to the specific etiology. Presented herewith case reports which were treated by Orthodontic treatment and also composite build-up. KEY WORDS: Midline Diastema, Treatment options INTRODUCTION:A space between adjacent teeth is called a "diastema". Midline diastemata (or diastemas) occur in approximately 98% of 6 year olds, 49% of 11 year olds and 7% of 12-18 year olds. 1 The midline diastema of the teeth is often a normal or developmental occurrence, due to the position of the teeth in their bony crypts, to the eruption path of the cuspids, and to the increase in size of the premaxilla at the time of eruption of the maxillary permanent central incisors 2 . Eruption, migration, and physiological readjustment of the teeth, labial and facial musculature, development into the beauty-conscious teenage group, the anterior component of the force of occlusion, and the increase in the size of the jaws with accompanying increase in tonicity of the facial musculature all tend to influence closure of the midline dental space. Since the frenum is considered a problem only if the teeth are separated, the effect of these natural forces is not only to close the midline dental space, but also automatically to eliminate the problem of the frenum. Relatively early in orthodontic literature, the superior labial frenum was listed as a cause of the midline diastema. Frenectomy was advised, and techniques for its removal were described. The number of frenectomies currently recommended by orthodontists is relatively small. Most of the respondents are treating the midline dental space Orthodontically without frenectomy. Often, people have a diastema treated for cosmetic reasons. They may be self-conscious about having a space between their teeth. However, a diastema also can affect speech. In cosmetic treatment, the direct-bonding restoration technique re -presents the preferred therapeutic option. It preserves maximal tooth structure and helps to

AIM: The aim of the present study was to compare the canal transportation and centering ability of three rotary nickel-titanium file systems, HyFlex controlled memory, Revo-S, and Mtwo in moderately curved root canals using computed tomography (CT). MATERIALS AND METHODS: Thirty freshly extracted single-rooted teeth having curved root canals with at least 10°–20° of curvature were selected. The teeth were divided into three experimental groups of ten each. After preparation with HyFlex CM (Coltene-Whaledent, Allstetten, Switzerland), Revo-S (Micro-Mega, Besançon, France), and Mtwo (VDW, Munich, Germany) all teeth were scanned using CT to determine the root canal shape. Pre- and post-instrumentation images were obtained at three levels, 3 mm apical, 9 mm middle, and 15 mm coronal above the apical foramen were compared using CT software. Amount of transportation and centering ability were assessed. The three groups were statistically compared with analysis of variance and post-hoc Tukey’s honestly significant difference test. RESULTS: Least apical transportation and higher centering ability were seen in HyFlex CM file system in all the three sections followed by Revo-S, Mtwo file system showed maximum transportation. CONCLUSIONS: According to the present in-vitro study, we can conclude that HyFlex CM rotary file systems showed least canal transportation and highest centering ability as compared to Revo-S and Mtwo file system but there was no statistically significant difference among these file systems (p > 0.05) at coronal, middle, and apical level of root canal.

Aims: The aim of this study is to compare three different methods of measuring root canal curvature and its correlation with canal access angle (CAA) in curved mesiobuccal canals of permanent mandibular first molars. Materials and Methods: Sixty human mandibular first molars were used in this study. Standardized access cavities were prepared. After endodontic access, a size 10 K-file was placed in the mesiobuccal canal extending to the apical foramen, and radiographs were taken. Radiographs of each root canal were taken in buccolingual direction with the long axis of the root perpendicular to the central X-ray beam. After that, the radiographs were scanned with a computer Scanner. The angles were measured using the Schneider method, Weine's method, Lutein's method, and correlated with the CAA method. The angular and linear values used in this study were plotted, and the pertinent measurements were made using the program AutoCAD R12. Statistical Analysis: The resultant values were evaluated statistically using ANOVA test and Pearson correlation and multiple regression analyses ( P = 0.001). Results: Lutein's method is as effective as the Schneider's method, Wein's method and CAA. method in evaluating root canal curvature. Conclusions: Scheider/Wein/Luiten method, together with CAA method, may be considered as a reliable guideline for preoperative assessment of canal curvature.