Effects of HEMA and TEDGMA on the in vitro odontogenic differentiation potential of human pulp stem/progenitor cells derived from deciduous teeth.

Objectives: The aim of this study was to investigate the effects of HEMA and TEGDMA on the odontogenic differentiation potential of dental pulp stem/progenitor cells.

Methods: Dental stem/progenitor cell cultures were established from pulp biopsies of human deciduous teeth of 1-3 year-old children (Deciduous Teeth Stem Cells-DTSCs). Cultures were characterized for stem cell markers, including STRO-1, CD146, CD34, CD45 using flow cytometry.

A meta-analysis of prosthodontic complication rates of implant-supported fixed dental prostheses in edentulous patients after an observation period of at least 5 years.

Purpose: To systematically review clinical studies on prosthodontic complication rates of implant fixed dental prostheses in edentulous patients after an observation period of at least 5 years.

Materials And Methods: A literature search was conducted using different electronic databases. Specific terms were used for the database search, which spanned the years 1990 to 2008.

Comparative analysis of in vitro osteo/odontogenic differentiation potential of human dental pulp stem cells (DPSCs) and stem cells from the apical papilla (SCAP).

Objective: The aim of this study was to compare the in vitro osteo/odontogenic differentiation potential of mesenchymal stem cells (MSCs) derived from the dental pulp (dental pulp stem cells - DPSCs) or the apical papilla (stem cells from the apical papilla - SCAP) of permanent developing teeth.

Design: DPSCs and SCAP cultures were established from impacted third molars of young healthy donors at the stage of root development. Cultures were analysed for stem cell markers, including STRO-1, CD146, CD34 and CD45 using flow cytometry.

Assessment of the impact of two different isolation methods on the osteo/odontogenic differentiation potential of human dental stem cells derived from deciduous teeth.

Human deciduous teeth have been proposed as a promising source of mesenchymal stem cells for application in bone and dental tissue engineering. We established cultures of mesenchymal stem cells from the pulp of human deciduous teeth (deciduous teeth stem cells, DTSCs) and analyzed their morphologic, growth, immunophenotypic, and osteo/odontogenic differentiation characteristics using different isolation methods and culturing environments. We compared the biologic behavior of DTSCs isolated either by enzymatic dissociation (DTSCs-ED) or by direct outgrowth from pulp tissue explants (DTSCs-OG).

Molecular toxicology of substances released from resin-based dental restorative materials.

Resin-based dental restorative materials are extensively used today in dentistry. However, significant concerns still remain regarding their biocompatibility. For this reason, significant scientific effort has been focused on the determination of the molecular toxicology of substances released by these biomaterials, using several tools for risk assessment, including exposure assessment, hazard identification and dose-response analysis.

Genotoxic and cytotoxic effects of different types of dental cement on normal cultured human lymphocytes.

In this study we have investigated the genotoxic and cytotoxic effects of eluates derived from different types of commercially available dental cements, including glass ionomer cements (GICs) (Ketac Cem/3M ESPE and GC Fuji I/GC Corp), resin-modified glass ionomer cements (RM-GICs) (RelyX Luting/3M ESPE and Vitrebond/3M ESPE) and dual-cure resin cements (RCs) (Variolink II/ Ivoclar-Vivadent and Panavia F 2.0/Kuraray) on normal cultured human lymphocytes. Lymphocyte primary cultures obtained from blood samples of three healthy donors were exposed to serial dilutions of eluates derived from specimens of each material tested.

Abutment screw loosening in single-implant restorations: a systematic review.

Purpose: The purpose of this study was to systematically review clinical studies on the incidence of abutment screw loosening in single-implant restorations with different implant-abutment connection geometries.

Materials And Methods: The literature search was conducted using several electronic databases. Specific terms were used for the database search, which spanned the years 1990 to 2006.

Shear bond strength of a light-cured veneering composite to fiber-reinforced composite substrates.

Purpose: The aim of this study was to compare the shear bond strength of a veneering composite to 2 differently treated fiber-reinforced composite (FRC) substrates and to a base metal alloy.

Materials And Methods: A veneering composite (SR Adoro) was bonded to the following substrates: (1) a nickel-chromium base metal alloy (control, group A), (2) an FRC substructure (Vectris) with a flat surface (group B), and (3) an FRC substructure (Vectris) with retentive rods 0.5 x 0.

Sister-chromatid exchange, chromosomal aberrations and delays in cell-cycle kinetics in human lymphocytes induced by dental composite resin eluates.

We have investigated eluates derived from commercially available composite resin-based materials used for direct (Tetric Ceram/Ivoclar-Vivadent, Simile/Pentron, Filtek Z-250/3M ESPE) and indirect (Adoro/Ivoclar-Vivadent and Conquest Sculpture/Pentron) dental restorations, with respect to their genotoxic effects on human peripheral lymphocytes. Primary lymphocyte cultures obtained from blood samples of three healthy donors were exposed to eluates of freshly cured specimens of all the materials tested. Metaphases were induced with phytohaemagglutinin, collected after a 72-h treatment using colchicine and stained with the Fluorescence Plus Giemsa (FPG) procedure.

The effect of thermal cycling and air abrasion on cement failure loads of 4 provisional luting agents used for the cementation of implant-supported fixed partial dentures.

Purpose: To investigate the effects of thermal cycling and surface roughness of metal implant abutments and the intaglio surface of the copings on the retentive properties of 4 provisional luting agents commonly used in the cementation of implant-retained fixed partial dentures (FPDs).

Materials And Methods: A 2-unit implant-retained FPD and a 4-unit implant-retained FPD were fabricated using gold-palladium alloy. The abutments used were 5 mm in height.

Patterns of cell death and cell cycle profiles of cultured WEHI 13 var fibroblasts exposed to eluates of composite resins used for direct and indirect restorations.

Previous studies have shown that in vitro exposure to single compounds released from composite resins may induce cell death. In the present study the effects of eluates from commercially available composite resins used for direct or indirect restorations were evaluated on the cell cycle progression and type of cell death of cultured WEHI 13 var fibroblasts. Cells exposed to eluates of the materials were assessed for cytotoxicity by the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay for cell death, for cell cycle profiles by flow cytometry, for caspase-3 biochemically and by immunocytochemistry, and for morphological changes by fluorescence microscopy with acridine orange.

Pre- and post-set hydrophilicity of elastomeric impression materials.

Purpose: To evaluate the hydrophilicity of one polyether, four poly(vinyl siloxanes), and one condensation silicone before and after setting under simulated clinical conditions, and to correlate the findings to the contact angle values of these materials.

Materials And Methods: The hydrophilicity before and after setting, as well as the contact angle values of the elastomeric impression materials were evaluated. Part I: A freshly extracted tooth, which was prepared for a full coverage restoration, was kept in saliva for 15 minutes and was then rinsed for 10 seconds.

Ultrasonographic thickness and electromyographic activity of masseter muscle of human females.

The aims of this study were to assess the thickness of the masseter muscle by means of ultrasonography and to investigate the relationship between masseter electromyographic activity and muscle thickness bilaterally, during maximum voluntary clenches. Participants in the study consisted of 52 young female adults (mean age 23.7 +/- 2.

Attachment and proliferation of human periodontal ligament fibroblasts on bioactive glass modified ceramics.

In this study, six groups of modified ceramic specimens were constructed and were studied comparatively with dental porcelain (P:control) for their ability to support human periodontal ligament fibroblasts attachment and proliferation. The dental porcelain was initially coated with bioactive glass (PCB) or with a mixture of porcelain and bioactive glass (PCBP) and then calcium-phosphate rich (Ca-P) or hydroxy-carbonate apatite (HCAp) layers were bio-mimetically developed on both surfaces (PCB and PCBP) after immersion in simulated body fluid. The development and characterization of Ca-P and HCAp layers on PCBCa-P, PCBHCAp, PCBPCa-P, PCBPHCAp specimens' surfaces were evaluated by Scanning Electron Microscopy (SEM) and further confirmed by Fourier Transform Infrared Spectroscopy (FTIR).

Specialisation and specialist education in prosthetic dentistry in Europe.

This presentation reports on the results of a meeting of prosthodontists from selected European countries. The aim of the meeting was to analyse and promote specialisation and specialist education in Prosthetic Dentistry in Europe. Representatives for Europe were selected from the European Prosthodontic Association (EPA) board, the Education and Research Committee of International College of Prosthodontists (ICP), countries with a legally recognised speciality, countries without a recognised speciality but organised training programmes and countries with neither of these situations.

In vitro assessment of cytotoxicity of resin-based dental restorative materials on WEHI 13 var fibroblasts.

Purpose: The aim of this study was to assess the cytotoxicity of 4 resin composites' eluates on WEHI 13 Var fibroblasts as they aged in a biologic medium.

Materials And Methods: Cytotoxicity was determined by counting the number of viable cells by trypan blue exclusion. Morphologic changes attributable to cytotoxicity were observed by May-Grunwald-Giemsa cytologic staining and microscopic examination.

A survey of the use of mandibular implant overdentures in 10 countries.

Purpose: This preliminary international survey compared provision of implant-retained overdentures to fixed implant-supported prostheses for edentulous mandibles.

Materials And Methods: Questionnaires based on a 2001 Swedish study were sent to prosthodontists and specialist clinics in nine additional countries.

Results: Response rate varied from 53% to 100% in 10 national surveys and should allow careful comparison of results.

Bonding indirect resin composites to metal: part 2. Effect of alloy surface treatment on elemental composition of alloy and bond strength.

Purpose: This laboratory study compared the effect of different surface treatments of a medium-gold, high-noble alloy on the shear bond strength of an indirect, highly filled resin composite to the alloy and on the elemental composition of the alloy surface.

Materials And Methods: Ninety disks, cast in a medium-gold, high-noble porcelain-fused-to-metal alloy (V-Deltaloy), received three different surface treatments: sandblasting with 50-microm Al2O3 (group 1) or 250-microm Al2O3 (group 2) and chemical agents, or with 250-microm Al2O3 without chemical agents (group 3) prior to bonding of an indirect resin composite (Artglass, and chemical agents Siloc-pre and Siloc-bond). The specimens were tested in shear, half of them after 24-hour dry storage at room temperature and the rest after 10-day storage in normal saline solution at 37 degrees C and thermocycling (2,500 cycles between 5 and 55 degrees C).

Bonding indirect resin composites to metal: Part 1. Comparison of shear bond strengths between different metal-resin bonding systems and a metal-ceramic system.

Purpose: This laboratory study compared the shear bond strength between three indirect resin composites and a noble alloy using their respective bonding systems.

Materials And Methods: One hundred twenty disks cast in a medium-gold, high-noble metal-ceramic alloy (V-Deltaloy) were divided equally into four groups and received different treatments for veneering: Conventional feldspathic porcelain (Omega) was applied on one set of specimens to be used as a control, and three indirect resin composites (Artglass, Sculpture, Targis) with their respective bonding systems were used for the other groups. The specimens were tested in a parallel shear test, half of them after 24-hour dry storage at room temperature and the rest after 10-day storage in normal saline solution at 37 degrees C and thermocycling.

Cement-retained versus screw-retained implant restorations: a critical review.

This article presents a comparison of screw-retained and cement-retained implant prostheses based on the literature. The advantages, disadvantages, and limitations of the 2 different types of restorations are discussed, because it is important to understand the influence of the attachment mechanism on many clinical aspects of implant dentistry. Several factors essential to the long-term success of any implant prosthesis were reviewed with regard to both methods of fixation.

Comparison of cell proliferation on modified dental ceramics.

The aim of this study was to investigate the influence of substrate characteristics such as chemical composition and surface morphology of dental ceramics to support cell attachment and proliferation. Thus, body (B) and shoulder (S) porcelain differing on their surface morphology and composition were treated with oxides CaO or CaO and P(2)O(5) and four modified ceramics BCa, BCaP, SCa, SCaP were constructed, respectively. The modified ceramics differ from their controls concerning their surface morphology as evaluated by Scanning Electron Microscope (SEM), and their surface chemical composition (Na, KP and Ca) as evaluated by Energy Dispersing Spectroscopy (EDS).

Shear bond strength of techniques for bonding esthetic veneers to metal.

Statement Of Problem: New composites with improved qualities have been introduced to the dental profession as alternatives to porcelain. There is concern about the strength and reliability of new metal-resin bonding systems when these composites are used as esthetic veneers over metal frameworks.

Purpose: This in vitro study compared the shear bond strength of 2 metal-resin bonding techniques with the bond strength of conventional porcelain fused-to-metal (PFM).

Effectiveness of conservative treatment for craniomandibular disorders: a 2-year longitudinal study.

The severity of symptoms of craniomandibular disorders was studied during a 2-year period in 195 patients treated with conservative therapeutic schemes. Results revealed a continuing improvement and a statistically significant tendency for the great majority of patients to become asymptomatic or show a decrease in the severity of symptoms. By the end of the 2 years, 66.

Effect of age and sex on craniomandibular disorders.

The purpose of this study was to investigate the effect of age and sex on craniomandibular disorders. A total of 195 subjects were examined, 148 women and 47 men. The range of age was 16 to 70 years.

[Influence of the sprue casting design on the surface porosity of the silver-palladium dental alloys].

The purpose of this work is to investigate and find out the best "design" of the casting sprues on the area and the number of the surface porosity when we cast silver-palladium dental alloys for metalloacrylics fixed partial dentures. Our observation and research have been done on 216 external surfaces from 72 M.O.