Morphological assessment of the surface profile, mesiodistal diameter, and contact tightness of Class II composite restorations using three matrix systems: An in vitro study.

Context: Sectional matrices and contact rings are valuable aids to establish proximal contact tightness in Class II composite restorations. Aims: This study aims to evaluate the proximal contact area in Class II composite restorations using three matrix systems based on morphological analysis, mesiodistal (M-D) diameter and contact tightness. Subjects and Methods: A standardized DO cavity was prepared in 30 plastic molar teeth. They were randomly divided into three groups (n = 10) and restored using Tetric N-Ceram composite material and three matrix systems - Saddle matrix, Palodent system, and Palodent Plus system. The quality of proximal contacts was assessed by measuring the maximum M-D diameter of the restored teeth using a digital caliper; the tightness of the proximal contact area using Unifloss and a standardized metal blade (30 µm). Qualitative assessment of contact morphology was done by visual means while quantitative assessment of contour was done using Medit scanner superimposing method and ExoCAD software. Statistical Analysis Used: One-way ANOVA test was used to compare the mean M-D diameter (in mm) in the occlusal third, middle third, and the proximal contact area between the three groups. Chi-square test was used to compare the proximal contact area tightness using the passage of Unifloss. The buccolingual and occluso-gingival morphology was also compared among the three groups. The level of significance (P value) was set at P < 0.05. Results: For the occlusal and middle third, significantly larger diameters were achieved with the Palodent Plus system than with the Saddle matrix. More flat contours were seen in the case of the Saddle matrix than in the case of the Palodent system while the Palodent Plus system exhibited a minimal depth of concavity as determined by three-dimensional imaging of the contact morphology. Conclusions: Palodent Plus and Palodent matrix systems established superior contacts and contours than the Saddle matrix.

Postspace pretreatment with 17% ethylenediamine tetraacetic acid, 7% maleic acid, and 1% phytic acid on bond strength of fiber posts luted with a self-adhesive resin cement.

Context: Pretreatment of radicular dentin with chelating agents improves the bond strength of fiber-posts luted with a self-adhesive resin cement. Aims: The aim of this study was to assess the effects of the three chelating agents as final rinse of the postspace on bond strength of fiber posts luted with a self-adhesive resin cement. Settings and Design: This is an in vitro laboratory study. Materials and Methods: Forty-five mandibular premolars were prepared using MTwo rotary system and irrigation was done with 2.5% sodium hypochlorite. Three groups of teeth samples were considered for postspace preparation and irrigated with different solutions: Group 1: 17% ethylenediamine tetraacetic acid (EDTA); Group 2: 7% Maleic acid; Group 3: 1% Phytic acid. This was followed by the luting the posts with RelyX U200. After a week, from each sample, 2 mm thick slices were obtained from each third of the root and subjected to push-out bond strength testing. Statistical Analysis Used: One-way analysis of variance and Bonferroni's Post hoc analysis was used for assessing the results. The statistical significance level was set at P < 0.05. Results: Bond strength values were improved with maleic acid and phytic acid pretreatment with slight or no significant difference between these groups. A final rinse of postspace with EDTA significantly reduced the bond strength. Conclusions: Maleic acid (7%) pretreatment of postspace improved the adhesion of fiber posts luted with a self-adhesive resin cement.

An in vitro comparative evaluation of the effect of three endodontic chelating agents (17% ethylenediamine tetraacetic acid, 1% peracetic acid, 0.2% chitosan) on the push out bond strength of gutta percha with a new bioceramic sealer (BioRoot RCS).

AIM: This study aims to evaluate the effect of three endodontic chelating agents (17% ethylenediamine tetra-acetic acid [EDTA], 1% peracetic acid [PAA], 0.2% Chitosan) on the push out bond strength of gutta percha with a new bioceramic sealer (BioRoot RCS). MATERIALS AND METHODS: Forty-eight single-rooted mandibular premolars were selected and decoronated to obtain standardized root length of 15 mm. The root canals were prepared up to #30 files (Hyflex CM) and copious irrigation was done with 3 ml of 5.25% of NaOCl. According to the final irrigation, specimens were divided into three groups: Group 1 (n = 16) 0.2% chitosan, Group 2 (n = 16) 17% EDTA, and Group 3 (n = 16) 1% PAA for 1 min. Samples from each group were obturated with bioceramic sealer and gutta percha and sealed with temporary filling material. Two horizontal slices of 2 mm was obtained from the middle third of each sample (n = 32). Push out bond strength and failure modes were assessed. Kruskal-Wallis test followed by Mann-Whitney post hoc analysis was used for push out analysis. Chi square test was used to compare the modes of failure. The statistical significance level was set at P = 0.05. RESULTS: The highest push out bond strength was obtained with Group 1 (0.2% chitosan) followed by Group 3 (1% PAA). Group 2 (17% EDTA) showed least push out bond strength when compared to Group 1 (0.2% chitosan) and Group 3 (1% PAA). The mode of failure was mainly cohesive for all groups. CONCLUSIONS: The highest push-out bond strength of BioRoot RCS was seen after treatment with 0.2% chitosan while the least was after EDTA treatment. 1% PAA treatment also favorably affected push-out bond strength of BioRoot RCS.

Retrievability of calcium hydroxide intracanal medicament with three calcium chelators, ethylenediaminetetraacetic acid, citric acid, and chitosan from root canals: An in vitro cone beam computed tomography volumetric analysis.

AIM: This study compared the amount of aqueous-based and oil-based calcium hydroxide remaining in the canal, after removal with two different chelators 17% EDTA, 20% Citric acid and 0.2% Chitosan in combination with ultrasonic agitation. METHODS AND MATERIAL: Cleaning and shaping of root canals of 28 mandibular premolar was done and canals were filled either with Metapex or Ca(OH)2 mixed with distilled water. Volumetric analysis was performed utilizing cone beam-computed tomography (CBCT) after seven days of incubation. Ca(OH)2 was removed using either 17% EDTA, 20% Citric acid or 0.2% Chitosan in combination with ultrasonic agitation. STATISTICAL ANALYSIS USED: Volumetric analysis was repeated and percentage difference was calculated and statistically analyzed using Kruskal-Wallis and Mann-Whitney U test. RESULTS: All the three chelators failed to remove aqueous-based as well as oil-based Ca(OH)2 completely from the root canal. Aqueous-based Ca(OH)2 was easier to be removed than oil-based Ca(OH)2. 0.2% Chitosan in combination with ultrasonics performed better than 17% EDTA and 20% citric acid in removal of Ca(OH)2. CONCLUSION: Combination of 0.2% Chitosan and ultrasonic agitation results in lower amount of Ca(OH)2 remnants than 17% EDTA, 20% Citric acid irrespective of type of vehicle present in the mix.

Smile rejuvenation: A case report.

Mesiodens is the commonly occurring supernumerary tooth seen between the maxillary central incisors which causes compromised aesthetics and malocclusion. Till date orthodontic therapy provides an excellent solution for the management of mesiodens. Recently, Restorative Space Management (RSM) has been used successfully to correct tooth shape, proportions and colour with minimal tooth preparations. This case report describes the successful management of an unaesthetic smile due to presence of a mesiodens in the midline primarily using aesthetic treatment only.

Effect of organic versus inorganic fluoride on enamel microhardness: An in vitro study.

INTRODUCTION: Dental caries is one of the most prevalent infectious diseases affecting the human dentition. Fluorides are effective anti-carious agents and have been widely used for caries prevention in the form of systemic and topical fluorides. Neutral sodium fluoride (NaF) is commonly used as a topical fluoride agent. A special category of topical fluorides are organic fluorides in the form of amine fluorides (AmF). Researchers have reported that AmF is superior to inorganic fluorides in improving the caries resistance of enamel due to the significant anti-enzyme effect of the organic fragment. AIM: The aim of the present study was to compare the enamel surface micro hardness after topical application of NaF and AmF solutions. MATERIALS AND METHODS: Twenty fresh samples of sound human enamel were treated with demineralizing solution for 72 h and divided into Group A (treated with NaF) and Group B (treated with AmF) solutions for 3 min twice daily for 7 days. In between treatment, the samples were stored in artificial saliva. The enamel surface hardness was measured with Vickers hardness test at baseline, post-demineralization and post-treatment with two different fluoride solutions (NaF and AmF) and a comparative analysis was made. RESULTS: The increase in mean micro hardness of human enamel after treatment with AmF application was found to be statistically significant (P < 0.01) when compared to the mean micro hardness after treatment with NaF. CONCLUSION: Fluoride enhances the remineralization process by accelerating the growth of enamel crystals that have been demineralized. It can be concluded from the present study that AmF compounds result in a marked increase in enamel micro hardness when compared to NaF.

Optimizing tooth form with direct posterior composite restorations.

Advances in material sciences and technology have provided today's clinicians the strategies to transform the mechanistic approach of operative dentistry into a biologic philosophy. In the last three decades, composite resins have gone from being just an esthetically pleasing way of restoring Class III and Class IV cavities to become the universal material for both anterior and posterior situations as they closely mimic the natural esthetics while restoring the form of the human dentition. In order to enhance their success, clinicians have to rethink their protocol instead of applying the same restorative concepts and principles practiced with metallic restorations. Paralleling the evolution of posterior composite resin materials, cavity designs, restorative techniques and armamentarium have also developed rapidly to successfully employ composite resins in Class II situations. Most of the earlier problems with posterior composites such as poor wear resistance, polymerization shrinkage, postoperative sensitivity, predictable bonding to dentin, etc., have been overcome to a major extent. However, the clinically relevant aspect of achieving tight contacts in Class II situations has challenged clinicians the most. This paper reviews the evolution of techniques and recent developments in achieving predictable contacts with posterior composites. A Medline search was performed for articles on "direct posterior composite contacts." The keywords used were "contacts and contours of posterior composites." The reference list of each article was manually checked for additional articles of relevance.