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Statement of problem.Different parameters can influence the adaptation of computer-aided design and computer-aided manufacturing (CAD-CAM) inlay/onlay restorations. However, systematic reviews to identify and discuss these parameters are lacking.Purpose. The purpose of this systematic review was to summarize the scientific literature investigating all parameters that can influence both the marginal and internal adaptation of CAD-CAM inlay/onlay restorations.Material and methods. An electronic search was conducted by 2 independent reviewers for studies published in English between January 1, 2007 and September 20, 2017 on the PubMed/Medline, Scopus, and Web of Science databases and in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) statement. Factors investigated in the selected articles included the type of CAD-CAM system, virtual space parameters, version of the software, type of block, luting procedure, type of restoration, sample size and aging procedure, evaluation method, and number of measurement points per specimen.Results. A total of 162 articles were identified, of which 23 met the inclusion criteria. Nine studies investigated adaptation with different restorative materials, 2 evaluated adaptation according to the type of preparation design, 9 compared adaptation before/after

ObjectivesThe aim of this study was to evaluate the mechanical and physical properties of a newly developed fiber reinforced dental composite.Materials and MethodsFiber reinforced composite EverX Posterior (EXP, GC EUROPE), and other commercially available bulk fill composites, including Filtek Bulk Fill (FB, 3M ESPE), SonicFill (SF, Kerr Corp.), SureFil (SDR, Dentsply), Venus Bulk Fill (VB, HerausKultzer), Tetric evoceram bulk fill (TECB, Ivoclar Vivadent), and Xtra Base (XB, Voco) were characterized. Composite samples light-cured with a LED device were evaluated in terms of flexural strength, flexural modulus (ISO 4049, n = 6), fracture toughness (n = 6), and Vickers hardness (0, 2, and 4 mm in depth at 24 hr, n = 5). The EXP samples and the fracture surface were observed under a scanning electron microscopy. Data were statistically analyzed using one-way ANOVA and unpaired t-test.ResultsEXP, FB, and VB had significantly higher fracture toughness value compared to all the other bulk composite types. SF, EXP, and XB were not statistically different, and had significantly higher flexural strength values compared to other tested composite materials. EXP had the highest flexural modulus, VB had the lowest values. Vickers hardness values revealed SF, EXP, TECB, and XB were not statistically different, and had significantly higher values compared to other tested composite materials. SEM observations show well dispersed fibers working as a reinforcing phase.ConclusionsThe addition of fibers to methacrylate-based matrix results in composites with either comparable or superior mechanical properties compared to the other bulk fill materials tested.

Background and objectivesA current public health issue is preventing post-surgical complications by designing antibacterial implants. To achieve this goal, in this study we evaluated the antibacterial activity of an animal-free chitosan grafted onto a titanium alloy.MethodsAnimal-free chitosan binding on the substrate was performed by covalent link via a two-step process using TriEthoxySilylPropyl Succinic Anhydride (TESPSA) as the coupling agent. All grafting steps were studied and validated by means of X-ray Photoelectron Spectroscopy (XPS), Time-of-Flight secondary ion mass spectrometry (ToF-SIMS) analyses and Dynamic-mode Secondary Ion Mass Spectrometry (DSIMS). The antibacterial activity against Escherichia coli and Staphylococcus aureus strains of the developed coating was assessed using the number of colony forming units (CFU).ResultsXPS showed a significant increase in the C and N atomic percentages assigned to the presence of chitosan. A thick layer of polymer deposit was detected by ToF-SIMS and the results obtained by DSIMS measurements are in agreement with ToF-SIMS and XPS analyses and confirms that the coating synthesis was a success. The developed coating was active against both gram negative and gram positive tested bacteria.ConclusionThe success of the chitosan immobilization was proven using the surface characterization techniques applied in this study. The coating was found to be effective against Escherichia coli and Staphylococcus aureus strains.

The aim of this study was to assess the effect of radiotherapy on bond efficiency of two different adhesive systems using tensile bond strength test. Twenty extracted teeth after radiotherapy and twenty nonirradiated extracted teeth were used. The irradiation was applied in vivo to a minimal dose of 50 Gy. The specimens of each group were randomly assigned to two subgroups to test two different adhesive systems. A three-step/etch-and-rinse adhesive system (Optibond FL) and a two-steps/self-etch adhesive system (Optibond XTR) were used. Composite buildups were performed with a nanohybrid composite (Herculite XTR). All specimens were submitted to thermocycling ageing (10000 cycles). The specimens were sectioned in 1 mm2 sticks. Microtensile bond strength tests were measured. Nonparametric statistical analyses were performed due to nonnormality of data. Optibond XTR on irradiated and nonirradiated teeth did not show any significant differences. However, Optibond FL bond strength was more effective on nonirradiated teeth than on irradiated teeth. Within the limitations of an in vitro study, it can be concluded that radiotherapy had a significant detrimental effect on bond strength to human dentin. However, it seems that adhesive choice could be adapted to the substrata. According to the present study, the two-steps/self-etch (Optibond XTR) adhesive system tested could be more effective on irradiated dentin compared to three-steps/etch-and-rinse adhesive system (Optibond FL).

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This paper presents the primary results of the development of a chewing bench prototype. The final aim of the device is to reproduce the human oral cavity environment in order to predict ageing of dental materials, it automatically imitates chewing cycles and reproduces the physical and chemical changes observed during meals. A dental articulator used for prosthodontics was chosen as an ideal structure for simulating human mandible kinematics; it has the advantage of being water tight compared to a hexapod device. Using OpenMeca® software and three motors the extreme movements of the mandible were replicated. Four thermally controlled tubs were used to mimic physical and chemical changes observed during meal. The chewing bench provides a valuable tool for the evaluation of dental materials; its relevance is based on the simultaneous presence of all parameters that affect dental materials during function (mechanical, thermal and chemical). It is the first stage of work which will be validated a posteriori. This chewing bench would hopefully reduce the gap between in vitro performance and in vivo observation and serve as a benchmark for existing materials and as a device for testing new ones.

Purpose To investigate the relationship between the microstructure of CAD/CAM blocks and the quality of adhesion as function of the surface treatment and resin cement type. Materials and methods Two nano‐ceramic composite resin CAD/CAM blocks, Lava Ultimate (LU) and Cerasmart (CS), and two Leucite‐reinforced glass ceramic CAD/CAM IPS blocks, Empress® CAD (EM) and InitialTM LRF (IR), received either Hydrofluoric acid (HF) or sandblasting (SB) surface treatments. The blocks were then luted using two dual‐cure resin cements, LinkForce (LF) and Multilink Automix (ML) with their corresponding silanes, resulting in 16 study groups. The luted blocks were then thermal‐cycling (TC) for 5000 cycles and subjected to a microtensile bond strength (μTBS) test. Scanning electron microscopy (SEM) micrographs of the treated surfaces were analyzed using ImageJ software and XRD analyses were performed for the two ceramic blocks. The data obtained were submitted to Games‐Howell post‐hoc nonparametric test to compare combinations of groups or treatments and a linear mixed‐effects model for the factors surface treatment, block type, and resin cement, together with their first‐degree interactions (α = 0.05). Results The lowest mean μTBS values were obtained with LU‐HF, whereas the highest mean μTBS values were obtained with CS regardless of resin cement type and surface treatment method. IR‐HF mean μTBS were significantly higher than IR‐SB, EM‐SB, and EM‐HF. Analysis using ImageJ software demonstrated significant differences in the density and pore size after HF surface treatment. Conclusions The specific microstructure of each block material within the same family group impacted the micromechanical retention and the bonded interface strength.