Objective: To investigate the effect of two acidic agents on microhardness of nanofilled and microhybrid resin composite materials.
Materials And Methods: 70 resin composite discs (10 mm diameter and 2 mm thick) were prepared from 2 resin composites (35 from each type), nanofilled (Z350XT) and microhybrid (Z250), 3M/ESPE. Ten discs (5 from each group) were used as control (tested at 1 h before immersion). Each group was divided into 3 subgroups ( = 10) according to the storage media: distilled water (control), box-type cola and orange juice. Each subgroup was further subdivided into 2 divisions ( = 5) according to microhardness testing at 24 h and 7days after immersions. Digital Vickers Microhardness Tester (FM-7, Future Tech, Tokyo, Japan) was used to measure surface microhardness with a Vickers diamond indenter. The surface of the specimens received a load of 200 g for 10 seconds. Three indentations not less than 1 mm from each other were placed on the surface of all specimens. Vickers hardness number (VHN) was calculated for each indentation Data were statistically analyzed using one- way ANOVA followed by Newman-keuls tests ( ≤ 0.05).
Results: Orange juice showed statistically significantly the lowest VHN mean value (92.7) followed by the Cola group (95.15) then the water group (104.02) compared to the control group (117.4). Microhybrid composite groups showed statistically significant higher VHN mean value (108.1) than the nanofilled composite (100.2). The 7days groups showed statistically significant lower VHN mean value (97.3) than 24h groups (106.6).
Conclusions: All storage media reduced hardness of resin composites with orange juice showing the highest reduction in hardness values. Microhybrid is more resistant to degradation than nanofilled composite. Over time, microhardness of resin composites decreased progressively.
Download full-text PDF |
Source |
---|---|
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC9369782 | PMC |
http://dx.doi.org/10.4103/jispcd.JISPCD_66_22 | DOI Listing |
BDJ Open
January 2025
Professor of Conservative Dentistry, Faculty of Dentistry, Cairo University, Giza, Egypt.
Objectives: To assess the validity of light-induced and laser-induced fluorescence devices compared to the visual-tactile method for detecting secondary caries around resin composite restorations.
Materials And Methods: The study included 20 participants with 30 resin-composite restored teeth. Restorations' margins were examined using three diagnostic methods: the visual-tactile method (FDI criteria), the light-induced fluorescence camera (VistaCam iX), and the laser-induced fluorescence device (DIAGNOdent pen), and the reference was visual inspection after removal of defective restorations.
J Esthet Restor Dent
January 2025
Magne Education, Beverly Hills, California, USA.
Objective: Chemicals used during canal disinfection and endodontic sealers have a deleterious effect on dentin bond strength. The aim of this study was to evaluate a novel clinical sequence to improve the resin-dentin microtensile bond strength (μTBS) to endodontically treated teeth.
Materials And Methods: Twenty human molars were distributed in four experimental groups (n = 5, N = 20): C-control group without exposure to any endodontic chemical substances (2.
Sci Rep
January 2025
Department of Materials Science and Engineering, Faculty of Mechanical Engineering, Budapest University of Technology and Economics, Műegyetem rkp. 3, Budapest, H-1111, Hungary.
Tooth degradation develops easily over time from initial caries to deeper cavities. The quality and durability of restorations are crucial in a patients' life, and it is primarily determined by the mechanical properties of the restorations. Clinicians and engineers apply biomimetic science in dentistry to mimic the natural design of the teeth and emphasize careful material selection as well as bond strength between the tissue and artificial material.
View Article and Find Full Text PDFDent Mater
January 2025
KU Leuven, Department of Oral Health Sciences, BIOMAT & UZ Leuven, Dentistry, Kapucijnenvoer 7, 3000 Leuven, Belgium. Electronic address:
Objectives: To evaluate the effect of different zirconia compositions and manufacturing processes on the light irradiance (LI), to measure the degree of conversion (DC) of solely light-curing restorative composite underneath these zirconia grades and to evaluate the respective zirconia microstructures.
Methods: Six dental zirconia grades (GC HT, GC UHT [GC]; Katana HT, Katana UTML [Kuraray Noritake]; Lava Esthetic, Lava Plus [3 M Oral Care]) were cut and sintered per manufacturer instructions. One 3D-printed zirconia grade (XJet [XJET]) was prepared according to previous research.
Dent Mater
January 2025
Minnesota Dental Research Center for Biomaterials and Biomechanics, School of Dentistry, University of Minnesota, Minneapolis, MN, USA. Electronic address:
Objective: This study compared the fracture load, stress distribution, and survival probability under cyclic loading of extensively restored teeth treated with multisonic irrigation with those treated with conventional instrumentation, with or without a post.
Methods: Mesial-occlusal-distal cavities were prepared in 30 human mandibular premolars. The teeth were randomly divided into 3 groups of 10 based on the endodontic and restorative procedures: (1) Root canal treatment (RCT) followed by resin composite restoration (control group), (2) RCT followed by a glass fiber post restoration (conventional group), and (3) minimal instrumentation plus multisonic irrigation followed by resin composite restoration (GW group).
Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!