Impact of restorative material on fracture behaviors of class II restoration in endodontically treated deciduous molars.

The purpose of this study was to investigate the fracture behavior of endodontically treated (ET) deciduous molar when directly restored with different restorative materials in Class II (MO) cavities in comparison with permanent teeth. MO cavities were prepared with 2.4-2.

Effect of splinting material type and location on resistance against deflection force of splinted periodontally compromised teeth with hypermobility.

This study aimed to evaluate the effect of splinting material type and material location on the force resistance of splinted periodontally compromised teeth with hypermobility. Extracted teeth including the target tooth (maxillary second premolar) and its adjacent teeth were placed into the alveolar sockets of a dental arch model via artificial periodontal ligaments made of elastic impression material. Three different experimental models with varied target tooth mobility including Periotest® values (PTVs) of 20, 30, and 40 were fabricated (named models #20, #30, and #40, respectively).

Influence of Post-Core and Crown Type on the Fracture Resistance of Incisors Submitted to Quasistatic Loading.

The aim of this paper was to evaluate the fracture resistance and failure type of maxillary incisor teeth, rebuilt with various types of post-core restorations and full crowns made of either direct conventional particulate filler composite (PFC, G-aenial Anterior, GC, Tokyo, Japan) or indirect CAD/CAM restorations (composite Cerasmart 270 and glass ceramic LiSi Block from GC). One hundred ( = 10/group) central incisors were cut and divided into 10 experimental groups restored with different approaches. In approach A, teeth were restored with a core build-up composite (Gradia Core, GC) for a core and full crown of PFC.

Impact of multiple firings and resin cement type on shear bond strength between zirconia and resin cements.

Purpose: The aim of this study was to evaluate the effect of multiple firings on the bond strength between yttria-tetragonal zirconia polycrystals (Y-TZP) and 2 types of resin cements.

Materials And Methods: Sixty 3Y-TZP specimens (LAVA Frame Multi) were divided into 3 groups depending on the following firing procedures: (1) 2-firing cycles, (2) 5-firing cycles, (3) 10-firing cycles. Two samples from each group were investigated by using SEM to determine the morphological changes.

Effect of various polymerization protocols on the cytotoxicity of conventional and self-adhesive resin-based luting cements.

Objectives: This study evaluated the cytotoxicity of resin-based luting cements on fibroblast cells using different polymerization protocols.

Materials And Methods: Two conventional dual-polymerized (RelyX ARC, VariolinkN) and two self-adhesive resin cements (RelyX Unicem, Multilink Speed) specimens were polymerized using four different polymerization protocols: (a) photo-polymerization with direct light application, (b) photo-polymerization over ceramic and (c) resin nano-ceramic discs and (d) auto-polymerization. The specimens were then assigned to four groups to test cytotoxicity at 0, 1, 2 and 7 preincubation days (n = 5).

Angle of convergence of posterior crown preparations made by predoctoral dental students.

The aim of this study was to determine angle of convergence (AC) of posterior crown preparations made by predoctoral dental students at the University of Toronto. Ninety-one dies of students' crown preparations were digitally scanned with an in-Eos-Blue scanner (Sirona). Created images were virtually sliced at three similar locations of mesiodistal and buccolingual planes.

Effects of different cavity designs on fracture load of fiber-reinforced adhesive fixed dental prostheses in the anterior region.

Purpose: To evaluate the fracture strength of inlay-retained, surface-retained, and cantilevered fiber-reinforced adhesively fixed dental prostheses (FRA-FDPs) in the anterior region.

Materials And Methods: Thirty-two sound human right central incisors and canines were divided into four groups. Test groups were as follows: group 1, both teeth had deep cavity preparation; group 2, both teeth had shallow cavity preparation; group 3, only the canine teeth had deep cavity preparation; group 4, no preparation was made on the abutment teeth.

Load-bearing capacity of fiber reinforced fixed composite bridges.

Objective: The aim of this study was to evaluate the reinforcing effect of differently oriented fibers on the load-bearing capacity of three-unit fixed dental prostheses (FDPs).

Materials And Methods: Forty-eight composite FDPs were fabricated. Specimens were divided into eight groups (n = 6/group; codes 1-8).

Tensile bond strength of a lithium-disilicate pressed glass ceramic to dentin of different surface treatments.

The effects of desensitizer, disinfectant, saliva, blood, and hydrogen peroxide on the tensile bond strength between adhesive and ceramic as well as between adhesive and dentin were examined. Sixty 7x3 mm pressed ceramic discs of IPS e.max were fabricated and randomly assigned to six groups of different dentin surface treatments (control, desensitizer, disinfectant, saliva, blood, and hydrogen peroxide).

Effect of ultrasonic agitation on bond strength of self-etching adhesives to dentin.

Purpose: The aim of this study was to evaluate the influence of ultrasonic treatment on the microtensile bond strength of self-etching adhesives to dentin.

Materials And Methods: Forty-two human molars were wet ground occlusally until dentin was exposed. Clearfil S3 Bond, Futurabond NR (one-bottle) and Clearfil SE Bond (two-bottle) self-etching bonding systems were used in this study.

In vitro evaluation of push-out bond strength of direct ceramic inlays to tooth surface with fiber-reinforced composite at the interface.

Statement Of Problem: Failure of a restoration, where a part of a ceramic inlay and/or a cusp is fractured, is a common clinical problem. The application of fiber-reinforced composites at the tooth-inlay interface may prevent undesirable fractures in dental restorations. There is little information regarding the effect of a fiber- reinforced composite layer on the push-out bond strength of ceramic inlays to tooth structure.

Effect of accelerated restorative techniques on the microleakage of Class II composites.

Purpose: To assess the marginal seal of Class II resin-based composite restorations cured by a high intensity halogen light or a plasma arc light.

Materials And Methods: Class II cavities were prepared in extracted molar teeth with cervical margins located apical to the cemento-enamel junction. Cavities were restored with a posterior resin-based composite (Tetric Ceram) using either a two-increment or a bulk placement and cure restorative technique after application of bonding agent (Excite).