Effect of luting cement thickness on the bond strength of glass fiber posts to dentin.

The objective of this study was to evaluate the effect of cement thickness and luting cement type on the push-out bond strength of glass fiber posts (GFPs) to root dentin. Sixty human maxillary root-filled canines or premolars with single straight roots were randomly divided into 6 groups (n = 10) according to the GFP configuration (conventional or relined with composite resin) and the cement used (RelyX U200, Ketac Cem, or Allcem Core). After endodontic treatment and GFP cementation, all of the roots were sectioned perpendicular to their long axis to obtain 1.

Crown Material and Occlusal Thickness Affect the Load Stress Dissipation on 3D Molar Crowns: Finite Element Analysis.

Purpose: To compare the mechanical behavior (stress load dissipation and/or concentration) of posterior crowns made from Lava Ultimate (LU; 3M ESPE) and IPS e.max CAD (LD; Ivoclar Vivadent) using finite element analysis (FEA).

Materials And Methods: A 3D model of a mandibular first molar was prepared by reducing the occlusal surface by 1 or 2 mm (according to group), the axial walls by 1.

Resting-state functional brain connectivity predicts cognitive performance: An exploratory study on a time-based prospective memory task.

Resting-state functional brain connectivity (rsFC) is in wide use for the investigation of a variety of cognitive neuroscience phenomena. In the first phase of this study, we explored the changes in EEG-reconstructed rsFC in young vs. older adults, in the both the open-eyes (OE) and the closed-eyes (CE) conditions.

Effect of indenter material on reliability of all-ceramic crowns.

Objectives: Controversy exists about whether the elastic modulus (E) mismatch between the loading indenter and ceramic materials influences fatigue testing results. The research hypotheses were that for porcelain veneered Y-TZP crowns 1) A low modulus Steatite indenter (SB) leads to higher fatigue reliability compared to a high modulus tungsten carbide indenter (WC); 2) Different surface damage patterns are expected between low and high modulus indenters after sliding contact fatigue testing. All ceramic crowns will exhibit similar step-stress accelerated life testing (SSALT) contact fatigue reliability (hypothesis 1) and failure characteristics (hypothesis 2) when using high stiffness tungsten carbide (WC, E = 600 GPa) vs.

Lifetime prediction of veneered versus monolithic lithium disilicate crowns loaded on marginal ridges.

Objective: To evaluate the probability of survival of monolithic and porcelain veneered lithium disilicate crowns comprised by a conventional or modified core when loaded on marginal ridges.

Methods: Lithium disilicate molar crowns (n=30) were fabricated to be tested at mesial and distal marginal ridges and were divided as follows: (1) bilayered crowns with even-thickness 0.5mm framework (Bi-EV); (2) bilayered crowns with modified core design (Bi-M-lingual collar connected to proximal struts), and: (3) monolithic crowns (MON).

Probability of survival of implant-supported metal ceramic and CAD/CAM resin nanoceramic crowns.

Objectives: To evaluate the probability of survival and failure modes of implant-supported resin nanoceramic relative to metal-ceramic crowns.

Methods: Resin nanoceramic molar crowns (LU) (Lava Ultimate, 3M ESPE, USA) were milled and metal-ceramic (MC) (Co-Cr alloy, Wirobond C+, Bego, USA) with identical anatomy were fabricated (n=21). The metal coping and a burnout-resin veneer were created by CAD/CAM, using an abutment (Stealth-abutment, Bicon LLC, USA) and a milled crown from the LU group as models for porcelain hot-pressing (GC-Initial IQ-Press, GC, USA).

Effects of implant diameter and prosthesis retention system on the reliability of single crowns.

Purpose: The probability of survival of implant-supported prostheses may be affected by the interplay between different implant diameters supporting screwed or cemented crowns. The purpose of this study was to investigate the effect of implant diameter and prosthesis retention system on the reliability and failure modes of single crowns.

Materials And Methods: Internal-hexagon implants were divided into six groups (n = 21 each) according to implant diameter (3.

Slow cooling protocol improves fatigue life of zirconia crowns.

Objective: To compare the fatigue life and damage modes of zirconia crowns fabricated with and without framework design modification when porcelain veneered using a fast or slow cooling protocol.

Methods: Composite resin replicas of a first molar full crown preparation were fabricated. Zirconia copings were milled as conventional (0.

Bone-Forming Capabilities of a Newly Developed NanoHA Composite Alloplast Infused with Collagen: A Pilot Study in the Sheep Mandible.

Lateral or vertical bone augmentation has always been a challenge, since the site is exposed to constant pressure from the soft tissue, and blood supply only exists from the donor site. Although, for such clinical cases, onlay grafting with autogenous bone is commonly selected, the invasiveness of the secondary surgical site and the relatively fast resorption rate have been reported as a drawback, which motivated the investigation of alternative approaches. This study evaluated the bone-forming capability of a novel nanoHA alloplast infused with collagen graft material made from biodegradable polylactic acid/polyglycolic acid versus a control graft material with the same synthesized alloplast without the nanoHA component and collagen infiltration.

Modification of xenogeneic graft materials for improved release of P-15 peptides in a calvarium defect model.

Particulate bone augmentation is an established clinical alternative to regenerate bone. However, in regions of poor bone quality or previously infected sites, the clinical outcomes are more inconsistent. For that purpose, peptides have been added to particulate materials in an attempt to render them with antibacterial properties or to improve their osseoconductivity.

Push-out bond strengths of different dental cements used to cement glass fiber posts.

Statement Of Problem: Since the introduction of glass fiber posts, irreversible vertical root fractures have become a rare occurrence; however, adhesive failure has become the primary failure mode.

Purpose: The purpose of this study was to evaluate the push-out bond strength of glass fiber posts cemented with different luting agents on 3 segments of the root.

Material And Methods: Eighty human maxillary canines with similar root lengths were randomly divided into 8 groups (n=10) according to the cement assessed (Rely X luting, Luting and Lining, Ketac Cem, Rely X ARC, Biscem, Duo-link, Rely X U100, and Variolink II).

MicroCT analysis of a retrieved root restored with a bonded fiber-reinforced composite dowel: a pilot study.

Purpose: This evaluation aimed to (1) validate micro-computed tomography (microCT) findings using scanning electron microscopy (SEM) imaging, and (2) quantify the volume of voids and the bonded surface area resulting from fiber-reinforced composite (FRC) dowel cementation technique using microCT scanning technology/3D reconstructing software.

Materials And Methods: A fiberglass dowel was cemented in a condemned maxillary lateral incisor prior to its extraction. A microCT scan was performed of the extracted tooth creating a large volume of data in DICOM format.

Surface characterisation and bonding of Y-TZP following non-thermal plasma treatment.

Objectives: (1) To chemically characterise Y-TZP surface via X-ray photoelectron spectroscopy (XPS) and evaluate the surface energy levels (SE) after non-thermal plasma (NTP). (2) To test the microtensile bond strength (MTBS) of Y-TZP bonded to cured composite disks, after a combination of different surface conditioning methods.

Methods: Twenty-four Y-TZP discs (13.

Internal fit of two all-ceramic systems and metal-ceramic crowns.

Objectives: The aim of this study was to investigate the internal fit (IF) of glass-infiltrated alumina (ICA--In-Ceram Alumina), yttria-stabilized tetragonal zirconia polycrystals (Y-TZP--IPS e.max ZirCAD), and metal-ceramic (MC--Ni-Cr alloy) crowns.

Material And Methods: Sixty standardized resin-tooth replicas of a maxillary first molar were produced for crown placement and divided into 3 groups (n=20 each) according to the core material used (metal, ICA or Y-TZP).

A multidisciplinary approach for the management of hypodontia: case report.

Hypodontia is the congenital absence of one or more teeth and may affect permanent teeth. Several options are indicated to treat hypodontia, including the maintenance of primary teeth or space redistribution for restorative treatment with partial adhesive bridges, tooth transplantation, and implants. However, a multidisciplinary approach is the most important requirement for the ideal treatment of hypodontia.

Sealing Capability and SEM Observation of the Implant-Abutment Interface.

To evaluate the sealing capability of external hexagon implant systems and assess the marginal fit, two groups (n = 10 each) were employed: SIN (Sistema de Implantes Nacional, Brazil) and Osseotite, (Biomet 3i, USA). Sealing capability was determined by placing 0.7 μL of 1% acid-red solution in the implant wells before the torque of their respective abutments.

Fatigue life and failure modes of crowns systems with a modified framework design.

Objectives: To evaluate the effect of framework design on the fatigue life and failure modes of metal ceramic (MC, Ni-Cr alloy core, VMK 95 porcelain veneer), glass-infiltrated alumina (ICA, In-Ceram Alumina/VM7), and veneered yttria-stabilized tetragonal zirconia polycrystals (Y-TZP, IPSe.max ZirCAD/IPS e.max,) crowns.