Additive-manufactured ceramics for dental restorations: a systematic review on mechanical perspective.

Background: Additive manufacturing (AM) is rapidly expanding as a substitute for conventional heat-pressing and milling techniques for ceramic restorations. However, experimental and clinical evidence on the mechanical properties and performance of the final ceramic products is yet insufficient. This systematic review aimed to update the latest advances in additive manufacturing of restorative ceramics with a focus on their mechanical properties.

In vitro cytotoxicity (irritant potency) of toothpaste ingredients.

Purpose: This study aimed to determine the cytotoxicity (irritant potency) of toothpaste ingredients, of which some had known to have sensitizing properties.

Materials: From the wide variety of toothpaste ingredients, Xylitol, Propylene glycol (PEG), Sodium metaphosphate (SMP), Lemon, Peppermint, Fluoride, Cinnamon, and Triclosan and Sodium dodecyl sulphate (SDS) have been selected for evaluation of their cytotoxic properties.

Methods: Reconstructed human gingiva (RHG) were topically exposed to toothpaste ingredients at different concentrations.

Relative abrasive potential of silica-based conventional and tablet dentifrices on enamel and dentin.

Objectives: This in vitro study aimed to investigate the toothbrushing wear on both enamel and dentin surfaces of reference and commercially available dentifrices.

Methods: Bovine enamel and dentin blocks were initially polished and embedded within a resin composite in square shapes (10×8×6 mm3). Employing toothbrushes equipped with nylon bristles, a toothbrushing machine was utilized, subjecting dentin specimens (n = 36) to 500 brush cycles and enamel samples to 5000 brush cycles (n = 36).

Release of contraction stress of dental resin composites by water sorption.

Unlabelled: Polymerization shrinkage of bonded resin composite restorations will result in the development of curing contraction stresses during setting and can cause debonding of the restoration or failure of the surrounding tooth structure. However, the hygroscopic expansion that occurs after exposure of the restorative to the wet oral environment can compensate for this shrinkage.

Objectives: The purpose of this study was to determine the hygroscopic expansion of six commercial resin composites and relate it to their composition, mechanical properties, shrinkage, and contraction stress development.

The influence of pre-heating the restoration and luting agent on the flexural strength of indirect ceramic and composite restorations.

Background: This study investigated the impact of luting procedure and restoration thicknesses on the flexural strength of CAD/CAM restorations. Traditional luting agents have been questioned in favor of pre-heated resin composites or flowable composites.

Materials And Methods: 400 disc-shaped restorations (lithium disilicate [IPS e.

Evaluating the use of self-conditioning adhesive combined with dual curing resin cement as an endodontic sealer: An in vitro study.

Objectives: To compare infiltration, sealing and microleakage in root dentin with a self-conditioning adhesive system combined with dual curing resin (resin-based cement) to a conventional epoxy-resin-based sealer using confocal microscopy imaging.

Methods: 26 roots were enlarged and disinfected. Dentin tubules of 24 teeth were labelled with a red fluorophore (Rhodamine B) (two samples served as controls).

An in-vitro study on effects of laser activation on dye penetration in human root dentin.

Objective: To evaluate the penetration of a dye in root dentin after activation with different laser wavelengths.

Materials: Palatal roots of 38 human molars were enlarged and disinfected. Irrigation activation was performed with an Er:YAG laser: @50 mJ, 15 Hz (Er:YAG); a 9.

Effect of crown retention systems and loading direction on the stress magnitude of posterior implant-supported restorations: A 3D-FEA.

This study aimed to investigate the effect of four retention systems for implant-supported posterior crowns under compressive loading using three-dimensional finite element analysis. A morse-taper dental implant (4.1 × 10 mm) was designed with Computer Aided Design software based on non-uniform rational B-spline surfaces.

Effect of brushing simulation on the wear behavior of repaired CAD-CAM restorations.

Objective: The aim of the present study was to evaluate the influence of multidirectional brushing on the surface roughness, morphology, and bonding interface of resin-repaired CAD-CAM ceramic and composite restorations.

Materials And Methods: Twelve (N = 12) blocks (4 mm × 4 mm × 2 mm for parallel axis; 5 mm × 4 mm × 2 mm for perpendicular axis) of lithium disilicate glass-ceramic (IPS e.max CAD, Ivoclar AG) and CAD-CAM resin composite (Tetric CAD, Ivoclar AG) were obtained and repaired with direct resin composite (Clearfil AP-X, Kuraray).

Activation of endodontic irrigants using a 9.3 µm CO₂ and diode lasers: A laboratory proof of concept model.

Purpose: To investigate the differences between irrigant propagation and temperature changes using laser-activated irrigation (LAI) at different settings in an artificial root canal model.

Methods: Using an artificial resin root canal model, irrigant activation was achieved in 19 experimental groups with eight samples each. A 9,300 nm CO₂ laser, two diode lasers with different settings (wavelengths 455, 808, 970, and 980 nm) were compared to 2,940 nm Er:YAG laser and traditional needle irrigation.

Repair protocols for indirect monolithic restorations: a literature review.

Despite the advancements in indirect monolithic restorations, technical complications may occur during function. To overcome this issues, intraoral repair using resin composite is a practical and low-cost procedure, being able to increase the restoration's longevity. This review aimed to evaluate the need for repair and suggest a standardized repair protocol to the main indirect restorative materials.

Effect of Surface Treatment and Resin Cement on the Bond Strength of an Advanced Lithium Disilicate.

Objectives:  The aim of the study was to evaluate the effect of surface treatment and resin cement on the bond strength of conventional and advanced lithium disilicates (ALDs).

Materials And Methods:  Ceramic slices (2 × 13 × 15 mm) of conventional lithium disilicate (LD) (IPS e.max CAD) and ALD (CEREC Tessera) were sectioned, polished, and divided into 16 groups ( = 10) according to the factors: ceramic, surface treatment, and resin cement (Panavia V5 and Variolink Esthetic DC).

Mechanical Behavior of Repaired Monolithic Crowns: A 3D Finite Element Analysis.

This study evaluated the mechanical behavior and risk of failure of three CAD-CAM crowns repaired with different resin composites through a three-dimensional (3D) finite element analysis. Three-dimensional models of different cusp-repaired (conventional nanohybrid, bulk-fill, and flowable resin composites) crowns made of zirconia, lithium disilicate, and CAD-CAM resin composite were designed, fixed at the cervical level, and loaded in 100 N at the working cusps, including the repaired one. The models were analyzed to determine the Maximum Principal and Maximum Shear stresses (MPa).

Effect of printing layer orientation and polishing on the fatigue strength of 3D-printed dental zirconia.

Objective: The aim of the study was to evaluate the influence of surface polishing and printing layer orientation on the fatigue behaviour of 3 mol% yttria-stabilized zirconia (3Y-TZP) by stereolithography (SLA) in comparison with subtractive manufacturing.

Materials And Methods: 60 experimental zirconia bar-shaped specimens were 3D-printed (P) via SLA, and 30 specimens were milled (M) from commercial zirconia block (Lava™ Frame, 3 M ESPE AG). All specimens had the same dimensions (1 mm × 1 mm x 12 mm) after sintering.

Does glaze firing affect the strength of advanced lithium disilicate after simulated defects?

Objective: To study the influence of glazing on strength repair of lithium disilicate glass-ceramics after defect incorporation in different production processing phases.

Materials And Methods: Bar-shaped specimens (1 × 1 × 12 mm, n = 280; 20/group) made from different lithium disilicate ceramics (IPS e.max CAD, Ivoclar, "LD" or advanced lithium disilicate CEREC Tessera, Dentsply Sirona, "ALD") were exposed to 7 different protocols: crystallized without (c) and with glaze layer (cg), with a defect incorporated before crystallization without (ic) and with glaze layer (icg), with a defect after crystallization without (ci) or with glaze layer (cig), and defect incorporated after the glaze layer (cgi).

One-piece endodontic crown fixed partial denture: Is it possible?

Statement Of Problem: Whether the replacement of a missing tooth with a fixed partial denture supported by an endodontically treated abutment could be improved with 1-piece endodontic crowns is unclear.

Purpose: The purpose of the study was to evaluate the mechanical behavior of a fixed partial denture (FPD) according to the preparation of the abutment teeth (1-piece endodontic crown or complete crown) in terms of stress magnitude in the prosthesis, cement layer, and tooth.

Material And Methods: A posterior model with 2 abutment teeth (first molar and first premolar) was modeled with a computer-aided design (CAD) software program for conducting a 3-dimensional finite element analysis (FEA).

The ability of mouthguards to protect veneered teeth: A 3D finite element analysis.

Background/aims: Professional and amateur athletes might have veneer restorations. The aim of this study was to investigate the protective effect of mouthguards on veneered anterior restorations.

Methods: A nonlinear dynamic analysis was performed to simulate conditions during an impact with or without a custom-made mouthguard.

Cytotoxicity and anti-biofilm properties of novel hybrid-glass-based caries infiltrant.

Objectives: To assess the cytotoxicity of an experimental hybrid-glass-based infiltrant and its effect on biofilm attachment, growth and metabolic activity, and to compare it to the resin-based infiltrant Icon.

Methods: Cytotoxicity of hybrid-glass-based material (EXP) and resin-based infiltrant Icon (Icon) was tested in direct contact tests on freshly cured (direct_mat) and on materials kept for 24 h in cell culture medium (direct_exmat), and extract test with materials 24-h extracts (extract). Cell viability of L929 mouse fibroblast cell line was measured with MTT assay, according to ISO10993-5:2009.

Dental biomechanics of root-analog implants in different bone types.

Statement Of Problem: When implants are applied to restore oral function, the masticatory load on the crown will lead to stress development in all parts of the crown-abutment-implant-bone system. An optimal design of the whole system will be important for sustained function.

Purpose: The purpose of this 3-dimensional (3D) finite element analysis (FEA) study was to evaluate the influence of the root-analog implant (RAI) design in molar rehabilitation and bone type.

Effect of hydrothermal aging on the microhardness of high- and low-viscosity conventional and additively manufactured polymers.

Statement Of Problem: Studies on the microhardness of novel additively manufactured polymers compared with well-established low- and high-viscosity composite resins with regard to chemical composition are lacking.

Purpose: The purpose of this in vitro study was to evaluate the effect of hydrothermal aging on the microhardness of various conventional and additively manufactured polymers.

Material And Methods: Cylindrically shaped specimens (N=240, n=10 per group) (Ø10×2 mm) were either additively manufactured (6 groups) or conventionally (6 groups) manufactured by using 3D (Optiprint Temp [OP; Dentona]; C&B MFH [ND; NextDent]; Saremco print CROWNTEC [SA; Saremco Dental AG]; Temp Print [TP; GC]; 3DELTA ETEMP [DM; Deltamed]; MED690 [ST; Stratasys, Ltd]) or conventional low (Gradia Direct [GR; GC]; Clearfil Majesty [CM; Kuraray Noritake]; Tetric EvoCeram [TE; Ivoclar AG]) and high (Gradia Direct Flo [GR-F; GC]; Clearfil Majesty Flow [CM-F; Kuraray Noritake]; Tetric EvoFlow [TE-F; Ivoclar AG]) viscous materials.

Nickel allergy is associated with a broad spectrum cytokine response.

Background: Nickel-induced proliferation or cytokine release by peripheral blood mononuclear cells may be used for in vitro diagnosis of nickel allergy.

Objectives: Aim of this study was to explore the nickel-specific cytokine profile to further elucidate the pathogenesis of nickel allergic contact dermatitis (ACD) and to identify potential new biomarkers for nickel ACD.

Methods: Peripheral blood mononuclear cells from patients and controls were cultured with T-cell skewing cytokine cocktails and/or nickel.

Effect of light-curing time and direction on microhardness of a light-cured resin composite to cement CAD-CAM restorations.

Purpose: To evaluate the effect of light-curing exposure time and location on polymerization of a restorative bulk-fill resin composite to lute endocrowns.

Methods: A light-cured restorative bulk-fill resin composite (Filtek One Bulk Fill) was submitted to direct light-curing by a high-power LED light-curing unit for 20 seconds as the positive control group (n= 10). Five more groups (n= 10) were light-cured in a natural tooth mold from two sites (labial and lingual) through a nanohybrid resin composite CAD-CAM restoration (Lava Ultimate A2 LT), for different irradiation times: 90 seconds per site, 40 seconds per site, 30 seconds per site, 20 seconds per site and 10 seconds per site.

Side effects of sodium lauryl sulfate applied in toothpastes: A scoping review.

Purpose: To perform a scoping review on the available literature regarding the side effects of sodium lauryl sulfate (SLS) used in toothpastes.

Methods: A scoping review was performed according to the PRISMA extension using PubMed. The electronic search was supplemented with a manual search for a complete overview.