Effect of modulated photoactivation of bulkfill composite on microleakage in fluorosed and nonfluorosed teeth: A confocal laser scanning microscopy study.

AIM: The aim of this study is to compare the microleakage of bulkfill composite activated by modulated photoactivation between fluorosed and nonfluorosed teeth using the confocal laser scanning microscope. METHODOLOGY: One hundred and twenty intact human premolar teeth with Thylstrup and Fejerskov index fluorosis index 0-4 were stored in 0.5% thymol at the room temperature until further use. Standardized Class V preparations of 2 mm depth, 3 mm width, and 2 mm height were prepared on the buccal surface. The cavities were etched with 37% phosphoric acid, rinsed and primed with Tetric N bond, cured for 20 s with Quartz Tungsten Halogen (QTH) variable intensity light-curing unit spectrum-800 operating at 450 mW/cm2. Later, bulk fill composite was placed in the cavity and cured. Depending on the curing mode used, all the fluorosed and nonfluorosed teeth were divided into three subgroups each (n = 20) - Conventional light curing, stepped curing, and pulse delayed curing. All samples were stored in distilled water at the room temperature for 24 h and subjected to 500 thermocycles. The prepared teeth were placed in 0.6% rhodamine solution for 48 h; sectioned longitudinally using a hard-tissue microtome and scanned under a confocal laser scanning electron microscope. Data were analyzed using the one-way ANNOVA, Wilcoxson signed-rank test, and Kruskal-Wallis test. RESULTS: Significant differences were observed between fluorosed and nonfluorosed groups. Intragroup comparisons showed significant differences between fluorosed step and conventional subgroups. CONCLUSION: Fluorosed teeth had higher microleakage values than nonfluorosed teeth. Pulse-delayed subgroup had the least microleakage to that of conventional and stepped curing subgroups, in both fluorosed and nonfluorosed groups.

Comparative Evaluation of Marginal Adaptation of Biodentine(TM) and Other Commonly Used Root End Filling Materials-An Invitro Study.

AIM: The purpose of this investigation was to evaluate the marginal adaptation of three root-end filling materials Glass ionomer cement, Mineral trioxide aggregate and Biodentine(TM). METHODOLOGY: Thirty human single-rooted teeth were resected 3 mm from the apex. Root-end cavities were then prepared using an ultrasonic tip and filled with one of the following materials Glass ionomer cement (GIC), Mineral trioxide aggregate (MTA) and a bioactive cement Biodentine(TM). The apical portions of the roots were then sectioned to obtain three 1 mm thick transversal sections. Confocal laser scanning microscopy (CLSM) was used to determine area of gaps and adaptation of the root-end filling materials with the dentin. The Post hoc test, a multiple comparison test was used for statistical data analysis. RESULTS: Statistical analysis showed lowest marginal gaps (11143.42±967.753m2) and good marginal adaptation with Biodentine(TM) followed by MTA (22300.97±3068.883m(2)) and highest marginal gaps with GIC (33388.17±12155.903m(2)) which were statistically significant (p<0.0001). CONCLUSION: A new root end filling material Biodentine(TM) showed better marginal adaptation than commonly used root end filling materials.

Comparative Evaluation of Push-out Bond Strength of Three Endodontic Sealers with and without Amoxicillin-An Invitro Study.

INTRODUCTION: The purpose of this study was to evaluate the sealing ability of three different root canal sealers with and without amoxicillin, using a push-out bond strength test. MATERIAL AND METHODS: Sixty single-rooted extracted human teeth were used for this study. Each tooth was instrumented and irrigated with 5.25% Sodium hypochlorite (NaOCl) and 17% EDTA. The teeth were then divided into six test groups: Gutta percha (GP)/AH Plus (Dentsply, Germany), GP/AH Plus with 10% amoxicillin (TEVA Pharmaceuticals Sellersville, PA), GP/Pulp Canal Sealer EWT (Extended Working Time, SybronEndo Orange, CA), GP/Pulp Canal Sealer EWT with amoxicillin, GP/Apexit Plus, GP/Apexit Plus (Vivadent, Tulsa, US) with amoxicillin. After the sealer was set, the entire root was sectioned into 1 mm thick slices. A push-out bond strength test was performed by using a universal testing machine. The Student's t-test was used to compare the sealer bond strength within the specific sealer test groups and within each sealer at apical, middle and coronal root levels. RESULTS: There was no significant difference between the groups within each sealer (p>0.05) with or without amoxicillin at the same root level. CONCLUSION: This study demonstrated that the addition of 10% by weight of amoxicillin does not significantly (p> 0.05) change the overall push-out bond strength of three endodontic sealers when compared at the apical, middle, and coronal tooth level.

Endodontic management of two-rooted mandibular premolars using spiral computed tomography: a report of two cases.

AIM: To present a unique case of mandibular first and second premolars with two roots and two root canals with the aid of spiral computed tomography (SCT). BACKGROUND: Confirmation of morphology of mandibular first and second premolars with the aid of SCT. CASE DESCRIPTION: Mandibular premolars usually have a single root and a single canal. The occurrence of two roots with two separate root canals is extremely rare. The use of SCT in this rare case greatly contributed toward making a confirmatory diagnosis and successful endodontic management. CONCLUSION: Successful nonsurgical endodontic management of mandibular first and second premolars with two separate roots and root canals has been presented. In this case, exact root canal anatomy could not be confirmed by using radiographs alone. Hence, the use of SCT helped us in making a confirmatory diagnosis. CLINICAL SIGNIFICANCE: Developmental anomalies can occur in any tooth and two rooted premolars are no exception. The complexity of such teeth has to be considered for planning endodontic treatment using latest diagnostic equipment to increase the chances of success.