Flexural strength and microhardness of anterior composites after accelerated aging

This study aimed to evaluate the flexural strength and microhardness of three different anterior composites after 10 000 thermocycles. The mechanical properties of a nano-fill composite (Filtek Ultimate Universal Restorative (FUR) (Enamel)), a nano-hybrid composite (Clearfil Majesty ES2 (ES2) (Enamel)), and a micro-hybrid composite (G Aenial Anterior (GAA)) were investigated in this study. For the microhardness test, 8-mm diameter and 2-mm thickness composite discs were used (n = 10), and for the flexural strength test, 25x2x2 mm bar-shaped specimens were prepared (n = 13). The specimens were tested at 24 h and after 10 000 thermocycles. Data were analyzed using two-way analysis of variance and the post-hoc Tukey test (p .05). Pearson correlation analysis revealed that there was a negative relationship between the mean hardness and flexural strength values (correlation coefficient = -0.367, p = .043). After 10 000 thermocycles, microhardness values of each material and flexural strength of ES2 and GAA decreased significantly according to 24 h. The nano-fill composite FUR displayed significantly higher microhardness values. However, each resin composite was statistically similar for flexural strength values. Ten thousand thermocycles significantly affected microhardness and flexural strength

EFFECT OF ANTI-HALITOSIS-MOUTH RINSES ON SURFACE PROPERTIES OF RESIN BASED RESTORATIVE DENTAL MATERIALS

Objectives: This in-vitro study aimed to investigate the effect of five different types of mouth rinses used for halitosis on color stability and surface roughness of two types of restorative materials. Materials and Methods: In this study, a total of 120 disc-shaped samples (10x2mm) were prepared with nano-hybrid resin composite (Filtek Z550) and giomer (Beautifill II) materials. Randomly selected samples were divided into six groups as five different mouth rinses (Listerine Fresh Burst, Listerine Total Care, Colgate Plax, Oderol, Halitosil) and a control group (distilled water). Initial color values were measured by spectrophotometer (Easyshade Compact) according to the CIELAB system, and roughness values (Ra) were measured by contact profilometer (Surtronic 25). All specimens were incubated in mouth rinses at 37° C for 12 hours and measurements were performed in the same procedure. Data were analyzed by using Kruskal-Wallis H and Bonferroni Post Hoc tests with the SPSS 24.0 program at a significance level of 0.05. Results: The results of this study showed that there was not a statistically significant increase in surface roughness values. There was a significant change in CIELAB values in all of the Beautifil II materials after the immersion in mouth rinses (P<0.05). There was a statistically significant difference between the color change values of Beautifil II and Filtek Z550 materials kept in the same mouth rinses (P<0.05). Beautifil II was exhibited color change with values above the clinically acceptable limit (ΔE>3.3). Conclusions: Color changes occurred in both of the restorative materials kept in different mouth rinses

Effect of different final irrigation solutions on dentinal tubule penetration depth and percentage of root canal sealer

WOS: 000304691200026PubMed ID: 22595128Introduction: The purpose of this study was to evaluate the effects of different solutions used for final irrigation on sealer penetration into dentinal tubules. Methods: Thirty-two recently extracted human mandibular premolar teeth were treated with sodium hypochlorite (NaOCl) irrigation. The samples were divided into 4 groups according to the final irrigation solution used: (1) the EDTA group: 17% EDTA + 2.5% NaOCl, (2) the maleic acid (MA) group: 7% MA + 2.5% NaOCl, (3) the citric acid (CA) group: 10% CA + 2.5% NaOCl, and (4) the control group: 2.5% NaOCl. All teeth were obturated using the cold lateral condensation technique with gutta-percha and AH 26 sealer (Dentsply; DeTrey, Konstanz, Germany) labeled with fluorescent dye. The teeth were sectioned at distances of 2, 5, and 8 mm from the root apex. Total percentage and maximum depth of sealer penetration were measured using confocal laser scanning microscopy. Results: The Kruskal-Wallis analysis results showed that there was a significant difference in the percentage and maximum depth of sealer penetration among all groups in all sections (P<.05). The coronal sections in each group showed a significantly higher percentage and maximum depth of sealer penetration than did the apical and middle sections (P<.05). Conclusions: Final irrigation with EDTA, MA, and CA after the use of NaOCl affected sealer penetration. However, there was no significant difference between these experimental groups (EDTA, MA, and CA) in all sections

Effect of Different Final Irrigation Solutions on Dentinal Tubule Penetration Depth and Percentage of Root Canal Sealer

Introduction: The purpose of this study was to evaluate the effects of different solutions used for final irrigation on sealer penetration into dentinal tubules. Methods: Thirty-two recently extracted human mandibular premolar teeth were treated with sodium hypochlorite (NaOCl) irrigation. The samples were divided into 4 groups according to the final irrigation solution used: (1) the EDTA group: 17% EDTA + 2.5% NaOCl, (2) the maleic acid (MA) group: 7% MA + 2.5% NaOCl, (3) the citric acid (CA) group: 10% CA + 2.5% NaOCl, and (4) the control group: 2.5% NaOCl. All teeth were obturated using the cold lateral condensation technique with gutta-percha and AH 26 sealer (Dentsply; DeTrey, Konstanz, Germany) labeled with fluorescent dye. The teeth were sectioned at distances of 2, 5, and 8 mm from the root apex. Total percentage and maximum depth of sealer penetration were measured using confocal laser scanning microscopy. Results: The Kruskal-Wallis analysis results showed that there was a significant difference in the percentage and maximum depth of sealer penetration among all groups in all sections (P<.05). The coronal sections in each group showed a significantly higher percentage and maximum depth of sealer penetration than did the apical and middle sections (P<.05). Conclusions: Final irrigation with EDTA, MA, and CA after the use of NaOCl affected sealer penetration. However, there was no significant difference between these experimental groups (EDTA, MA, and CA) in all sections. (J Endod 2012;38:860-863

Pulp Diagnostic Tests

Pulp diagnostic tests evaluate the neuropsychological status and blood flow of the pulp. These tests can be used in conjunction with other clinical tests, such as periodontal probing, percussion, palpation, mobility, and anesthesia, during diagnostic tests. In clinical practice, it is important to determine the pulp condition in deciding the correct treatment to be applied. The aim of this review is to provide information about the pulp diagnostic tests that are used in dental practice and to generalize the correct use of these tests

Fracture resistance of endodontically treated molars restored with polyethylene fiber and different posts

The purpose of this study was to compare the fracture strength and mode of teeth restored with fiber/titanium post, polyethylene fiber, and adhesive composite. The mesial, distal, and palatal walls of human maxillary molar teeth were removed, so that only the buccal wall remained. Group 1, with caries-free maxillary molars, was used as a positive control group and the remaining groups were restored as follows: group 2, with only adhesive composite; group 3, with polyethylene fiber and adhesive composite; group 4, with fiber post and adhesive composite; group 5, with fiber post, polyethylene fiber, and adhesive composite; group 6, with titanium post and adhesive composite; and group 7, with titanium post, polyethylene fiber, and adhesive composite. A universal testing machine was used for fracture tests. Compressive loads were applied at an angle of 90 degrees on the occlusal surface of the specimens at crosshead speed of 1 mm/min until fracture occurred. Kruskal-Wallis and Mann-Whitney U tests were adopted for statistical analysis. The study shows that, based on the fracture strength, the group of teeth that were restored with glass fiber post, polyethylene fiber, and adhesive composite has the most significant improvement over all the other teeth groups. Based on the fracture mode, the teeth groups restored with only glass fiber post, adhesive composite, polyethylene fiber, and adhesive composite have relatively more restorable fractures observed

Inhibition of cell survival, viability and proliferation by dentin adhesives after direct and indirect exposure in vitro

WOS: 000311362300016PubMed ID: 22222515Objectives The influence of dentin adhesive systems (Scotchbond Multi-Purpose, XP Bond, Xeno V, Clearfil Protect Bond, AdheSE) on cell survival, viability and proliferation was characterized after direct and indirect exposure using different cell culture techniques. Materials and methods The primers and cured bonding parts were directly exposed to cells using cell culture inserts, and complete materials were analyzed in a dentin barrier test. Cell responses were examined in 3T3 mouse fibroblasts after 24- and 72-h exposure periods by the estimation of total cell numbers (survival), apoptosis (viability) and cell proliferation. Results Cell numbers were effectively reduced by the primers of AdheSE, Protect Bond, and Scotchbond Multi-Purpose as well as XP bond after direct exposure in a cell culture insert test device. Likewise, Scotchbond Multi-Purpose primer induced a rate of apoptosis (93.9%) even higher than detected with Protect Bond primer (91.6%). Cell proliferation was entirely inhibited by primers and by Xp Bond as well. The Scotchbond Multi-Purpose was most cytotoxic in a dentin barrier test device after a 24-h indirect exposure. It also increased the percentage of cells in apoptosis to 15.4% compared to untreated controls. Conclusion Unpolymerized primers of dentin adhesives were more cytotoxic than polymerized bonding counterparts. Moreover, total etch dentin adhesives were more cytotoxic than self-etch adhesives. Clinical relevance When dentin adhesives are used in deep cavities without a protective dentin barrier the leachable hydrophobic and hydrophilic component of dentin adhesive systems can penetrate to the pulp and may induce cytotoxic responses in pulp tissues.Scientific Research Projects Coordination Unit of Istanbul University [3230]The current study is based on a thesis submitted to the graduate faculty, University of Istanbul, in partial fulfillment of the requirements for the degree of Doctor of Philosophy and was supported by Scientific Research Projects Coordination Unit of Istanbul University. Project number 3230