Modified Mineral Trioxide Aggregate-A Versatile Dental Material: An Insight on Applications and Newer Advancements.

Mineral Trioxide Aggregate (MTA) has been a material of revolution in the field of dentistry since its introduction in the 1990s. It is being extensively used for perforation repairs, apexification, root-end filling, obturation, tooth fracture repair, regenerative procedures, apexogenesis, pulpotomies, and as a pulp-capping material because of its desired features such as biocompatibility, bioactivity, hydrophilicity, sealing ability, and low solubility. Even though its application is wide, it has its own drawbacks that prevent it from reaching its full potential as a comprehensive replacement material, including a long setting time, discoloration, mud-like consistency, and poor handling characteristics. MTA is a material of research interest currently, and many ongoing studies are still in process. In this review, the newer advancements of this versatile material by modification of its physical, chemical, and biological properties, such as change in its setting time, addressing the discoloration issue, inclusion of antimicrobial property, improved strength, regenerative ability, and biocompatibility will be discussed. Hence, it is important to have knowledge of the traditional and newer advancements of MTA to fulfill the shortcomings associated with the material.

Influence of Filler Composition on the Refractive Index of Four Different Enamel Shades of Composite Resins.

AIM AND OBJECTIVE: The purpose of this study was to measure the refractive index of four commercially available enamel resin composites, using optical coherence tomography (OCT) and their relationship with the atomic composition of the composite resin fillers utilizing an energy-dispersive X-ray fluorescence spectrometer (EDX). MATERIALS AND METHODS: Four different enamel composites, namely Enamel HRi color UE3, Enamel HFO color GE3, Vit-l-escence color Pearl Frost, and Amelogen Plus color Enamel White were tested. For each composite, disks with different thicknesses were fabricated and then light-cured according to the manufacturer's instructions. The disks were then stored in deionized water under 36.5 °C for at least 7 days. Each of the samples from the four different groups was measured in five distinctive points to analyze the optical and physical length using optical coherence tomography (OCT). Elemental analysis of all four different enamel shades of the composite was done using an EDX. RESULTS: The filler contents showed interesting differences in elemental composition and concentration; however, Si seemed to be a common filler component. The HRi composite presented a distinctive composition compared to other materials and was the only composite that showed a smaller percentage of SiO2, and also was the only composite that contained compounds, such as P2O5, ZnO, CaO, La2O3, and V2O5. The optical coherence tomography analysis showed the refractive index values of all tested enamel composites. Among the four different enamel composite resins tested, the enamel HRi composite demonstrated the most ideal refractive index to mimic natural enamel. CONCLUSION: The enamel HRi composite demonstrated a distinctive filler composition and this could be the main reason behind its higher refractive index. Nonetheless, it remains unclear how much of an impact this feature has in the final esthetic outcome of anterior composite restorations, where many other optical phenomena are also important. CLINICAL SIGNIFICANCE: The clinical success of any esthetic restorative procedure depends on diagnosing the proper treatment plan and also on executing this treatment with the right materials. On direct esthetic restorations, knowing the optical properties of such materials is fundamental, as they should be able to replicate both natural enamel and dentin. How to cite this article: Beolchi RS, Mehta D, Pelissier B, et al. Influence of Filler Composition on the Refractive Index of Four Different Enamel Shades of Composite Resins. J Contemp Dent Pract 2021;22(5):557-561.

The relationship of shammah (Arabian snuff) chewing to the risk of oral cancer and oral potentially malignant disorders.

INTRODUCTION: Shammah is a form of smokeless tobacco commonly used in the Arabian Peninsula. The data on the harmful effects of shammah on oral health, particularly oral malignancies, are scarce. The aim of this review was to explore the association between shammah use and development of oral potentially malignant disorders (OPMD) and/or oral cancer. MATERIALS AND METHODS: PubMed, EMBASE, Scopus, Web of Science and grey literature from January 1990 up to and including April 2018 were searched. Two independent reviewers performed the study selection according to eligibility criteria. RESULTS: A total of 10 studies that met the eligibility criteria were included. The odds of developing OPMD and/or oral cancer in relation to shammah use varied, with one study reporting a 39 increased risk (39, 95% CI: 14-105). The associated increased risk was relatively low among those that have stopped using shammah and ranged from threefold (3.65; 95% CI: 1.40-9.50) to 12-fold (12.6; 95% CI: 3.3-48.2). CONCLUSION: Shammah use seems to increase the risk of development of OPMD and/or oral cancer.

Clinical evaluation of mineral trioxide aggregate and biodentine as direct pulp capping agents in carious teeth.

BACKGROUND: Root canal treatment has been a routine treatment option for carious exposure of the dental pulp. In the context of minimally invasive dentistry, direct pulp capping (DPC) procedure with a reliable biomaterial may be considered as an alternative provided the pulp status is favorable. Mineral trioxide aggregate (MTA), a bioactive cement with excellent sealing ability and biocompatibility is capable of regenerating relatively damaged pulp and formation of dentin bridge when used as DPC agent. Biodentine is comparatively a new biomaterial claimed to possess properties similar to MTA and is currently explored for vital pulp therapy procedures. AIM: The aim of the present study was to evaluate the clinical response of pulp-dentin complex after DPC with MTA and biodentine in carious teeth. SUBJECTS AND METHODS: Twenty-four permanent molars with carious exposure having no signs and symptoms of irreversible pulpitis were selected and assigned to one of the two groups, Group I - MTA and Group II - biodentine. Patients were recalled at 3 weeks, 3 months, and 6 months for clinical and radiographic evaluation. Fisher's exact test was used along with Chi-square test for statistical analysis. RESULTS: Over a period of 6 months, MTA and biodentine showed 91.7% and 83.3% success rate, respectively, based on the subjective symptoms, pulp sensibility tests, and radiographic appearance. CONCLUSION: MTA and biodentine may be used as DPC agents when the pulpal diagnosis is not more than reversible pulpitis.

Adhesive Bonding to Computer-aided Design/ Computer-aided Manufacturing Esthetic Dental Materials: An Overview.

AIM: To review the adhesive bonding to different computer-aided design/computer-aided manufacturing (CAD/CAM) esthetic restorative materials. BACKGROUND: The use of CAD/CAM esthetic restorative materials has gained popularity in recent years. Several CAD/ CAM esthetic restorative materials are commercially available. Adhesive bonding is a major determinant of success of CAD/ CAM restorations. Review result: An account of the currently available bonding strategies are discussed with their rationale in various CAD/ CAM materials. CONCLUSION: Different surface treatment methods as well as adhesion promoters can be used to achieve reliable bonding of CAD/CAM restorative materials. Selection of bonding strategy to such material is determined based on its composition. Further evidence is required to evaluate the effect of new surface treatment methods, such as nonthermal atmospheric plasma and self-etching ceramic primer on bonding to different dental ceramics. CLINICAL SIGNIFICANCE: An understanding of the currently available bonding strategies to CA/CAM materials can help the clinician to select the most indicated system for each category of materials.

Tooth Wear Patterns among Khat and Shammah Users in Jazan City, Kingdom of Saudi Arabia: A Cross-sectional Survey.

AIM: The effect of Khat and Shammah habits, with the para-functional jaw activities that accompany them, on the structure and integrity of the natural dentition has not yet been investigated. The literature lacks studies that identify the patterns of tooth wear among Khat and Shammah users. Therefore, this study is the first attempt to address this concern in Jazan City population, Kingdom of Saudi Arabia. MATERIALS AND METHODS: A cross-sectional survey study was conducted among 300 recruits among dental clinics in Jazan City, Kingdom of Saudi Arabia from October 1, 2015, to April 30, 2016. Questionnaires were used for data collection on oral habits (Khat and Shammah use), age, gender, intake of acidic food or beverages, food habits (intake of fruits, grains, and vegetables), systemic diseases, oral hygiene habits (brushing frequency, technique, and type of toothbrush), parafunctional habits, stress, and acid reflux. Clinical examination was performed to assess the grade of tooth wear. Bivariate analysis was performed to determine the empirical relationship between the independent variables and outcomes. In addition, binary logistic regressions were used to measure the relationship between the independent variables and each of the dependent variables (presence of occlusal wear, tooth wear grade 0 through 4). RESULTS: Khat and Shammah use was statistically significantly associated with tooth wear (p < 0.05). A significant association of tooth wear was observed with age, gender, intake of acidic food and beverages, oral hygiene habits, and stress. CONCLUSION: Consumption of Khat and Shammah may be attributed as one of the major reasons associated with tooth wear among the Saudi population. CLINICAL SIGNIFICANCE: The habitual use of Khat and Shammah causes tooth wear of varying severity, which may negatively affect esthetics, phonetics, and function and necessitate a complex restorative treatment.

Patterns of Restorative Failure among Khat and Shammah Users in Jazan City, Kingdom of Saudi Arabia: A Cross-sectional Survey.

INTRODUCTION: The effect of Khat and Shammah habits, with the parafunctional jaw activities that accompany them, on the integrity of the natural dentition, dental restorations, and prostheses has not yet been investigated. This study is the first attempt to identify the patterns of restorative failure among Khat chewers and Shammah users in Jazan City, Kingdom of Saudi Arabia. MATERIALS AND METHODS: A cross-sectional study was conducted in 294 recruits among dental clinics in Jazan City, Kingdom of Saudi Arabia, from October 1, 2015, to April 30, 2016. The patients were surveyed and examined to identify the type of restorations/prosthesis they had and their failures. Bivariate analysis was conducted to investigate the association of the restorative failure with the demographic variables. General linear model was performed to investigate the association between restorations/prostheses failure and Khat/Shammah use with the controlling factors of age and gender as independent variables. RESULTS: Khat/Shammah use was statistically significantly associated with restorative failure (p < 0.05) relative to amalgam, composite, crowns, fixed partial dentures, removable partial dentures, and complete dentures. In addition, a significant association of restorative failure was observed with gender, education, and brushing. CONCLUSION: Consumption of Khat/Shammah may be attributed as one of the reasons associated with restorative failure among the Saudi population.

Study of the Mechanical Properties of the Novel Zirconia-reinforced Glass lonomer Cement.

OBJECTIVES: The purpose of this in vitro study is to compare the compressive strength (CS) and diametral tensile strength (DTS) of the zirconia-reinforced restorative material (Zirconomer®) with conventional glass ionomers (Fuji 1X) and amalgam. MATERIALS AND METHODS: Specimens (n = 120) were fabricated from silver amalgam, reinforced glass ionomer cement (GIC) (glass ionomer, Fuji 1X GC Corp.), and zirconia-reinforced glass ionomer (Zirconomer, Shofu Inc.) for testing the CS and DTS. The results were analyzed using analysis of variance, followed by a Tukey post hoc test. RESULTS: Both CS and DTS were found to be significantly higher for the zirconia-reinforced GIC and silver amalgam compared with GIC (p < 0.001). CONCLUSION: A newer class of restorative material like Zirconomer helps to overcome the potential hazard of mercury, but retains the strength and durability of amalgam as well as the sustained high-fluoride release of GICs. Furthermore, long-term studies are required to confirm its use as an alternative to the currently available posterior restorative material.

Evaluation of Bond Strength, Marginal Integrity, and Fracture Strength of Bulk- vs Incrementally-filled Restorations.

PURPOSE: This study evaluated the effect of application technique and preparation size on the fracture strength (FS), microtensile bond strength (µTBS) and marginal integrity (MI) of direct resin composite restorations. MATERIALS AND METHODS: Conservative (5 × 2 × 2 mm) or extended (5 × 4 × 2 mm) preparations below the cementoenamel junction were performed in 140 human maxillary premolars (n = 70 per group). After adhesive application (XP Bond), half of each group was restored with the bulk technique (one 4-mm increment of Surefill SDR Flow plus one 1-mm horizontal capping layer of TPH3 [Spectrum TPH3 resin composite]) and half incrementally (TPH3 in three horizontal incremental layers, 1.5 to 2 mm each), all using a metal matrix band. After storage (24 h at 37°C), the proximal surfaces of each tooth were polished with Sof-Lex disks. For FS measurement, 60 restorations were mounted in a universal testing machine and subjected to a compressive axial load applied parallel to the long axis of the tooth, running at a crosshead speed of 0.5 mm/min. For µTBS testing, 40 teeth were longitudinally sectioned to obtain resin-dentin bonded sticks from the cavity floor (bonded area: 0.8 mm2). Specimens were tested in tension at 0.5 mm/min. The external marginal integrity of both proximal surfaces was analyzed using SEM of epoxy resin replicas. The µTBS, marginal integrity, and fracture resistance data were subjected to two-way ANOVA, and Tukey's post-hoc test was used for pair-wise comparisons (a = 0.05). RESULTS: Fracture resistance, microtensile bond strength, and marginal integrity values were not statistically significantly affected by application technique or preparation size (p = 0.71, p = 0.82, and p = 0.77, respectively). CONCLUSIONS: The use of a bulk-fill flowable composite associated with a conventional resin composite as a final capping layer did not jeopardize the fracture strength, bond strength to dentin, or marginal integrity of posterior restorations.

Chemical Plaque Control Strategies in the Prevention of Biofilm-associated Oral Diseases.

Dental plaque is a biofilm that forms naturally on the surfaces of exposed teeth and other areas of the oral cavity. It is the primary etiological factor for the most frequently occurring oral diseases, such as dental caries and periodontal diseases. Specific, nonspecific, and ecologic plaque hypothesis explains the causation of dental and associated diseases. Adequate control of biofilm accumulation on teeth has been the cornerstone of prevention of periodontitis and dental caries. Mechanical plaque control is the mainstay for prevention of oral diseases, but it requires patient cooperation and motivation; therefore, chemical plaque control agents act as useful adjuvants for achieving the desired results. Hence, it is imperative for the clinicians to update their knowledge in chemical antiplaque agents and other developments for the effective management of plaque biofilm-associated diseases. This article explores the critical analysis of various chemical plaque control strategies and the current trends in the control and prevention of dental plaque biofilm.

Nd:YAG Laser to obtain Irregularities on the Inner Surface of Porcelain.

AIM: The aim of this study was to evaluate the inner surface of two ceramic systems: IPS Empress II (Ivoclar Vivadent, Germany) and In-Ceram Alumina (Vita Zahnfabrick, Germany) submitted to surface treatments, especially by Nd:YAG laser. MATERIALS AND METHODS: Fifty samples were prepared in pellet form for each ceramic system according to manufacturers' specifications. The samples were stored at room temperature and then be subjected to surface treatment: without treatment (T0) (control), hydrofluoric acid-etched (T1), hydrofluoric acid-etched associated with the airborne particle-abraded (T2); CoJet system (T3), Nd:YAG laser (T4). The data were performed the statistical analysis by ANOVA and Tukey's test (p < 0.001). RESULTS: The group control (T0) of the ceramics, the analysis showed the lowest roughness values; for the System Alumina In-Ceram, treatment with hydrofluoric acid (T1), associated with hydrofluoric acid and airborne particle-abraded (T2) and Nd:YAG laser (T4), had no statistically significant difference, whereas for the IPS Empress System II treatment with hydrofluoric acid (T1) and hydrofluoric acid associated with airborne particle-abraded (T2), had no statistically significant difference between the system and also CoJet (T3) and hydrofluoric acid associated with the airborne particle-abraded (T2). Photomicrographs of scanning electron microscopy showed different characteristics to the treatments for each ceramic system. CONCLUSION: The IPS Empress II had the appearance of favoring the retention when treated with hydrofluoric acid, as well as its association with the airborne particle-abraded. Uncertainty in Alumina, treatment with hydrofluoric acid associated with the airborne particle-abraded and CoJet system and provided a surface with irregularities. With respect to the laser further studies should be performed for parameters that are ideal for your application. CLINICAL RELEVANCE: The ceramic restorations are attractive due of their excellent esthetics and the ability to stay for long periods. However, the retention of ceramic requires further study.

Can Whitening Strips interfere with the Bond Strength of Composite Resins?

AIM: The aim of this study was to investigate in vitro the bond strength of composite resins on enamel previously treated with whitening strips. MATERIALS AND METHODS: A total of 48 bovine incisors were allocated to four experimental groups (n = 12 each): G1 (WSC)- treated with 9.5% hydrogen peroxide whitening strips (3D White Whitestrips® Advanced Vivid/CREST); G2 (WSO)-treated with 10% hydrogen peroxide whitening strips (3D WhiteTM/Oral B); G3 (WG)-treated with 7.5% hydrogen peroxide gel with fluorine, calcium and potassium nitrate (White Class®/FGM); and G4 (C)-control not subjected to bleaching treatment. The specimens were subjected to bleaching over 2 weeks following the manufacturers' instructions. Following the elaboration of the composite resin test specimens, the samples were stored in artificial saliva and subsequently subjected to the micro-shear test using the universal testing machine (EMIC®). The bond strength values were analyzed by one-way ANOVA and Tukey's statistical test (5%). RESULTS: Significant differences were observed among the investigated groups (p < 0.05). The G3-WG exhibited greater values compared with the control group and the groups treated with strips, G1-WSC and G2-WSO. Analysis of the bond interface revealed that a large fraction of the failures occurred at the enamel-resin interface. CONCLUSION: The bond strength decreased following 14 days of treatment with bleaching strips, whereas the whitening gel with 7.5% hydrogen peroxide, calcium and fluorine increased the bond strength.

Semidirect Restorations in Multidisciplinary Treatment: Viable Option for Children and Teenagers.

Due to the esthetic necessity required nowadays, the multidisciplinary treatment became a fundamental step in the restoration success. When the patient exhibits dental agenesis of one or more elements, he can show difficulty in social interactions. The age of the patient is a limiting factor to esthetic procedures, however, it should be evaluated as a real indicative with each case. The utilization of semi-direct restorations is a viable option due the cost, esthetic and improvement of physical and mechanical properties. The purpose of this paper is to present a case detailing the confection and cementation of anterior semi-direct restorations aimed at an anatomic reestablishment associated with integrated treatment with periodontics and orthodontics.

Multidisciplinary Treatment of a Fenestration-type Defect.

The case report aimed at treating a fenestration-type defect with multidisciplinary conventional and advanced surgical techniques. Fenestrations are isolated areas in which the exposed root surface is covered only by the periosteum and gingiva, but the remaining cortical bone remains intact. Root coverage is indicated in cases of root hypersensitivity, treatment of shallow caries lesions, cervical abrasions, and esthetic and cosmetic needs. In this case report, after proper hygiene instruction and dental biofilm control, a fenestration-type defect was treated using guided tissue regeneration (anorganic bovine matrix and resorbable membrane) and a connective tissue grafts, associated to an endodontic apicoectomy. After reevaluation, the remaining gingival recession was treated with a second gingival connective tissue graft covered with q double papillae type in order to reconstruct the periodontal tissues of the involved tooth. In this clinical case, the interaction between the different areas of dentistry has made it possible to correct a fenestration-type defect, following procedures based on scientific evidence, restoring periodontal health, esthetics, self-esteem, and meeting the patient's expectations regarding her initial complaint. This case report shows the important role of interdisciplinary approach to treating a patient with a complex periodontal defect that required different types of knowledge and abilities to achieve the best results based on the current status of dentistry possibilities.

Influence of standard load micro- and nanopatterned in surface roughness of bleached teeth and submitted to different surface treatments.

The aim of this study was evaluate the dental enamel after whitening treatment with Opalescence Boost PF™ 38%, correlating the structural alterations in the surface of the enamel with its respective pH and verify if whitened teeth submitted to different finishing and polishing techniques show similar surface texture to healthy teeth (control group). Sixty premolars were divided in 6 groups (n = 10), which had been immersed in artificial saliva during all the experiment. Protocol whitening was performed according to the manufacturer recommendations, and then the specimens were submitted to different polishing technique with Sof-Lex Pop On™ disks, Flex Diamond™ felt disks using two different micrometric polishing pastes (Enamelize™ and Diamond Polish™) and two nanometric polishing pastes (Lummina-E Diamond and Lummina-E Alumina), according to the groups. Representative specimens were analyzed in scanning electronic microscopy (SEM). Whitening gel used in this experiment had modified the morphologic aspect of the enamel surface. It was found that two nanometric polishing pastes (G5 and G6) promoted a less rough surface compared to control group even after the whitening process.

The Effect of Self-adhesive and Self-etching Resin Cements on the Bond Strength of Nonmetallic Posts in Different Root Thirds.

PURPOSE: The purpose of this study was to evaluate the effect of self-adhesive and self-etching resin cements on the bond strength of nonmetallic posts in different root regions. MATERIALS AND METHODS: Sixty single-rooted human teeth were decoronated, endodontically treated, post-space prepared, and divided into six groups. Glass-fiber (GF) posts (Exacto, Angelus) and fiber-reinforced composite (FRC) posts (EverStick, StickTeck) were cemented with self-adhesive resin cement (Breeze) (SA) (Pentral Clinical) and self-etching resin cement (Panavia-F) (SE) (Kuraray). Six 1-mm-thick rods were obtained from the cervical (C), middle (M), and apical (A) regions of the roots. The specimens were then subjected to microtensile testing in a special machine (BISCO; Schaumburg, IL, USA) at a crosshead speed of 0.5 mm/min. Microtensile bond strength data were analyzed with two-way ANOVA and Tukey's tests. RESULTS: Means (and SD) of the MPa were: GF/SA/C: 14.32 (2.84), GF/SA/M: 10.69 (2.72), GF/SA/A: 6.77 (2.17), GF/SE/C: 11.56 (4.13), GF/SE/M: 6.49 (2.54), GF/SE/A: 3.60 (1.29), FRC/SA/C: 16.89 (2.66), FRC/SA/M: 13.18 (2.19), FRC/SA/A: 8.45 (1.77), FRC/SE/C: 13.69 (3.26), FRC/SE/M: 9.58 (2.23), FRC/SE/A: 5.62 (2.12). The difference among the regions was statistically significant for all groups (p < 0.05). The self-adhesive resin cement showed better results than the self-etching resin cement when compared to each post (p < 0.05). No statistically significant differences in bond strengths of the resin cements when comparable to each post (p > 0.05). CONCLUSION: The bond strength values were significantly affected by the resin cement and the highest values were found for self-adhesive resin cement.

Comparative Evaluation of Two Final Irrigation Techniques for the Removal of Precipitate Formed by the Interaction between Sodium Hypochlorite and Chlorhexidine.

AIM: To evaluate the effectiveness of two final irrigation techniques for the removal of precipitate formed by the interaction between sodium hypochlorite (NaOCl) and chlorhexidine (CHX). MATERIALS AND METHODS: Sixty freshly extracted human maxillary incisor teeth were taken and randomly divided into three groups, containing 20 teeth each. Group 1 (control group), were irrigated with 5 ml of 2.5% NaOCl and a final flush with 5 ml of 2% chlorhexidine. Group 2 were irrigated with 5 ml of 2.5% NaOCl and 5 ml of 2% chlorhexidine followed by 5 ml of saline and agitated with F-files. Group 3 were irrigated with 5 ml of 2.5% NaOCl and 5 ml of 2% chlorhexidine followed by 5 ml of 15% citric acid and passively agitated with ultrasonics. A thin longitudinal groove was made along the buccal and lingual aspect of the root using diamond disks and split with chisel and mallet. Both halves of the split tooth will be examined under stereomicroscope. Results were tabulated and analyzed statistically using analysis of variance (ANOVA) and Mann-Whitney U test. RESULT: There was a significant difference between the mean values (p < 0.05) in groups 2 and 3 compared to group 1 at each level. CONCLUSION: Passive ultrasonic irrigation is more effective than the F-file agitation technique to remove the precipitate at all three levels measured. CLINICAL SIGNIFICANCE: Combination of sodium hypochlorite and chlorhexidine irrigation protocol has been practiced since from many years to achieve good results. However, it has adverse effect in the form of precipitate and which is considered to be a carcinogenic in nature, hence this precipitate should be removed.

Quantitative assessment of apical debris extrusion and intracanal debris in the apical third, using hand instrumentation and three rotary instrumentation systems.

INTRODUCTION: Decreased apical extrusion of debris and apical one third debris have strong implications for decreased incidence of postoperative inflammation and pain. Thus, the aim of this study was to assess quantitatively the apical extrusion of debris and intracanal debris in the apical third during root canal instrumentation using hand and three different types of rotary instruments. METHODOLOGY: Sixty freshly extracted single rooted human teeth were randomly divided into four groups. Canal preparation was done using step-back with hand instrumentation, crown-down technique with respect to ProTaper and K3, and hybrid technique with LightSpeed LSX. Irrigation was done with NaOCl, EDTA, and normal saline and for final irrigation, EndoVac system was used. The apically extruded debris was collected on the pre-weighed Millipore plastic filter disk and weighed using microbalance. The teeth were submitted to the histological processing. Sections from the apical third were analyzed by a trinocular research microscope that was coupled to a computer where the images were captured and analyzed using image proplus V4.1.0.0 software. The mean weight of extruded debris for each group and intracanal debris in the root canal was statistically analyzed by a Kruskal-Wallis one-way analysis of variance and Mann-Whitney U test. RESULTS: The result showed that, hand instrumentation using K files showed the highest amount of debris extrusion apically when compared to ProTaper, K3 and LightSpeed LSX. The result also showed that there was no statistically significant difference between the groups in relation to presence of intracanal debris in the apical one third. CONCLUSION: Based on the results, all instrumentation techniques produced debris extrusion. The engine driven Ni-Ti systems extruded significantly less apical debris than hand instrumentation. There was no statistically significant difference between the groups in relation to presence of intracanal debris in the apical one third.

Comparison of linear measurements and analyses taken from plaster models and three-dimensional images.

Digital models are an alternative for carrying out analyses and devising treatment plans in orthodontics. The objective of this study was to evaluate the accuracy and the reproducibility of measurements of tooth sizes, interdental distances and analyses of occlusion using plaster models and their digital images. Thirty pairs of plaster models were chosen at random, and the digital images of each plaster model were obtained using a laser scanner (3Shape R-700, 3Shape A/S). With the plaster models, the measurements were taken using a caliper (Mitutoyo Digimatic(®), Mitutoyo (UK) Ltd) and the MicroScribe (MS) 3DX (Immersion, San Jose, Calif). For the digital images, the measurement tools used were those from the O3d software (Widialabs, Brazil). The data obtained were compared statistically using the Dahlberg formula, analysis of variance and the Tukey test (p < 0.05). The majority of the measurements, obtained using the caliper and O3d were identical, and both were significantly different from those obtained using the MS. Intra-examiner agreement was lowest when using the MS. The results demonstrated that the accuracy and reproducibility of the tooth measurements and analyses from the plaster models using the caliper and from the digital models using O3d software were identical.

Comparison of Radicular Peroxide Leakage from four Commonly used Bleaching agents following Intracoronal Bleaching in Endodontically treated teeth - An In Vitro Study.

BACKGROUND: Non vital bleaching is simple, conservative procedure for esthetic correction of discolored endodontically treated teeth. The aim of this study was to determine and compare the amount of peroxide leakage from four different bleaching agents i.e superoxol, sodium perborate, combination of superoxol & sodium perborate and carbamide peroxide during intracoronal bleaching, as the safe and effective bleaching is the need of the hour. MATERIALS & METHODS: 50 extracted maxillary centrals were selected for the study. Following standardized protocol access, cleaning and shaping by step back technique and obturation was done using guttapercha and AH plus sealer. Access was sealed with Cavit G and outer root surface was coated with wax and nail varnish. The teeth were separated into crown and root and the root portion was placed in plastic tube containing distilled water for 7days.After incubation, 3mm of gutta-percha was removed below CEJ and 2mm glass ionomer cement base was placed. Grouped into five categories based on the bleaching agent placed in pulp chamber as -group1 (control)-distilled water, group 2-sodium perborate with distilled water , group 3- 30% hydrogen peroxide ,group 4-mixture of sodium perborate and 30% hydrogen peroxide and group 5-10% carbamide peroxide gel. Peroxide leakage was measured after 24hrs using ferrothiocyanate method and optical density using spectrophotometer. Statistical analysis of the data was conducted using ANOVA and multiple comparisons within the groups was done using BONFERRONI method (Post-Hoc tests). RESULTS: The results showed highest peroxide penetration from 30% hydrogen peroxide followed by mixture of sodium perborate with 30% hydrogen peroxide, mixture of sodium perborate with distilled water and least penetration from 10% carbamide peroxide gel. The results were statistically significant. CONCLUSION: Radicular peroxide leakage in 10% carbamide peroxide was significantly lower than the other tested bleaching agents making it a very safe alternative for intracoronal bleaching. How to cite this article: Madhu KS, Hegde S, Mathew S, Lata DA, Bhandi SH, Shruthi N. Comparison of Radicular Peroxide Leakage from four Commonly used Bleaching agents following Intracoronal Bleaching in Endodontically treated teeth - An In Vitro Study. J Int Oral Health 2013; 5(4):49-55.