Flexural test as an alternative to tensile test for bond strength of resin cement to zirconia.

Objective: There has been a great many technical difficulties in measuring the bond strengths between brittle dental substrates and materials, especially in preparing specimens. This study evaluated the validity of the relatively easy flexural bond strength (FBS) test in measuring bond strength of resin cement to zirconia as an alternative to the cumbersome tensile bond strength (TBS) and micro-tensile bond strength (MTBS) tests.

Materials And Methods: The FBS and TBS of resin cement to zirconia were measured experimentally after three surface treatments on a zirconia ceramic: air abrasion only (A), conditioning with Single Bond Universal (U) after air abrasion, and conditioning with Z-Prime Plus (Z) after air abrasion.

Improved resin-to-dentin bond strength and durability via non-thermal atmospheric pressure plasma drying of etched dentin.

This study aimed to evaluate the improvement in strength and durability of the bond between dentin and composite resins following plasma drying of the etched dentin surface using non-thermal atmospheric pressure plasma. Plasma drying was applied to the etched dentin before applying adhesive. Conventional wet-bonding and helium (He) gas-dried bonding schemes were used as control groups.

Anatomical analysis of the resected roots of mandibular first molars after failed non-surgical retreatment.

Objectives: Understanding the reason for an unsuccessful non-surgical endodontic treatment outcome, as well as the complex anatomy of the root canal system, is very important. This study examined the cross-sectional root canal structure of mandibular first molars confirmed to have failed non-surgical root canal treatment using digital images obtained during intentional replantation surgery, as well as the causative factors of the failed conventional endodontic treatments.

Materials And Methods: This study evaluated 115 mandibular first molars.

Promotion of resin bonding to dental zirconia ceramic using plasma deposition of tetramethylsilane and benzene.

The aim of this study was to investigate the effects of plasma-enhanced deposition of an organosilane and benzene on resin bonding to a dental zirconia ceramic. A total of 70 zirconia specimens, which were polished before sintering, were randomly divided into five groups according to surface treatments before applying a dental adhesive (each group, n = 14): group 1, no previous treatment (control); group 2, plasma deposition with tetramethylsilane (TMS); group 3, plasma deposition with benzene; group 4, sequential plasma deposition with TMS and benzene; and group 5, a zirconia primer (Z-Prime Plus). A dental adhesive (Scotchbond Multi-Purpose adhesive) was applied to the surface-treated zirconia, and resin composite rods were built in to enable shear bond-strength testing.

Marginal and internal fit of nano-composite CAD/CAM restorations.

Objectives: The purpose of this study was to compare the marginal and internal fit of nano-composite CAD-CAM restorations.

Materials And Methods: A full veneer crown and an mesio-occluso-distal (MOD) inlay cavity, which were prepared on extracted human molars, were used as templates of epoxy resin replicas. The prepared teeth were scanned and CAD-CAM restorations were milled using Lava Ultimate (LU) and experimental nano-composite CAD/CAM blocks (EB) under the same milling parameters.

Promotion of adhesive penetration and resin bond strength to dentin using non-thermal atmospheric pressure plasma.

Non-thermal atmospheric pressure plasmas (NT-APPs) have been shown to improve the bond strength of resin composites to demineralized dentin surfaces. Based on a wet-bonding philosophy, it is believed that a rewetting procedure is necessary after treatment with NT-APP because of its air-drying effect. This study investigated the effect of 'plasma-drying' on the bond strength of an etch-and-rinse adhesive to dentin by comparison with the wet-bonding technique.

Evaluation of electrical impedance ratio measurements in accuracy of electronic apex locators.

Objectives: The aim of this paper was evaluating the ratios of electrical impedance measurements reported in previous studies through a correlation analysis in order to explicit it as the contributing factor to the accuracy of electronic apex locator (EAL).

Materials And Methods: The literature regarding electrical property measurements of EALs was screened using Medline and Embase. All data acquired were plotted to identify correlations between impedance and log-scaled frequency.

Epigenetics: general characteristics and implications for oral health.

Genetic information such as DNA sequences has been limited to fully explain mechanisms of gene regulation and disease process. Epigenetic mechanisms, which include DNA methylation, histone modification and non-coding RNAs, can regulate gene expression and affect progression of disease. Although studies focused on epigenetics are being actively investigated in the field of medicine and biology, epigenetics in dental research is at the early stages.

Effects of non-thermal atmospheric pressure pulsed plasma on the adhesion and durability of resin composite to dentin.

This study investigated the effect of low-power, non-thermal atmospheric pressure plasma (NT-APP) treatments, in pulsed and conventional modes, on the adhesion of resin composite to dentin and on the durability of the bond between resin composite and dentin. A pencil-type NT-APP jet was applied in pulsed and conventional modes to acid-etched dentin. The microtensile bond strength (MTBS) of resin composite to dentin was evaluated at 24 h and after thermocycling in one control group (no plasma) and in two experimental groups (pulsed plasma and conventional plasma groups) using the Scotchbond Multi-Purpose Plus Adhesive System.

Performance of a novel polishing rubber wheel in improving surface roughness of feldspathic porcelain.

Replacing glazing with polishing is still controversial in terms of the surface roughness of dental porcelains. This study investigated the polishing performance of a ceramic-polishing rubber wheel (CP-RW), which contains large uniform and rounded silicon carbide particles and small diamond particles, in improving the surface roughness of two feldspathic porcelains for sintering and CAD/CAM milling. Using a confocal laser scanning microscopy, the changes in the surface roughness parameters were evaluated before and after polishing or glazing for three surface treatment groups: SofLex polishing, CP-RW polishing, and Glazing.

Influence of preparation design on fit and ceramic thickness of CEREC 3 partial ceramic crowns after cementation.

Objective: This study investigated the influence of preparation design on the marginal and internal gap and ceramic thickness of partial ceramic crowns (PCCs) fabricated with the CEREC 3 system.

Materials And Methods: Sixteen extracted human mandibular molars were prepared according to two different preparation designs (n = 8): a retentive preparation design with traditional cusp capping (Group I) and a non-retentive preparation design with horizontal reduction of cusps (Group II). PCCs were fabricated from IPS Empress CAD with the CEREC 3 system.

Comparison of shear test methods for evaluating the bond strength of resin cement to zirconia ceramic.

Objective: This study compared the sensitivity of three shear test methods for measuring the shear bond strength (SBS) of resin cement to zirconia ceramic and evaluated the effects of surface treatment methods on the bonding.

Materials And Methods: Polished zirconia ceramic (Cercon base, DeguDent) discs were randomly divided into four surface treatment groups: no treatment (C), airborne-particle abrasion (A), conditioning with Alloy primer (Kuraray Medical Co.) (P) and conditioning with Alloy primer after airborne-particle abrasion (AP).

Evaluation of the shear bond strength of resin cement to Y-TZP ceramic after different surface treatments.

The purpose of this study was to evaluate the effect of various surface treatments on the shear bond strength of Y-TZP (Yttria-Tetragonal Zirconia Polycrystal) ceramics with zirconia primer and two different resin cements both containing 10-methacryloyloxydecyl dihydrogen phosphate (MDP). Zirconia blocks (LAVA, 3M ESPE, St. Paul, MN) were polished and assigned to five groups according to the surface treatment: (1) no further treatment (control); (2) airborne abrasion with Al2 O3 particles; (3) Z-PRIME Plus (Bisco, Schaumburg, IL) applied on polished zirconia; (4) Z-PRIME Plus applied on zirconia after airborne abrasion; and (5) tribochemical silica-coating performed with the CoJet system (3M ESPE) followed by application of ESPE®-Sil (3M ESPE).

Plasma in dentistry: a review of basic concepts and applications in dentistry.

Objective: Plasma-related technologies are essential in modern industries. Recently, plasma has attracted increased attention in the biomedical field. This paper provides a basic knowledge of plasma and a narrative review of plasma applications in dentistry.

Thermal irritation of teeth during dental treatment procedures.

While it is reasonably well known that certain dental procedures increase the temperature of the tooth's surface, of greater interest is their potential damaging effect on the pulp and tooth-supporting tissues. Previous studies have investigated the responses of the pulp, periodontal ligament, and alveolar bone to thermal irritation and the temperature at which thermal damage is initiated. There are also many in vitro studies that have measured the temperature increase of the pulp and tooth-supporting tissues during restorative and endodontic procedures.

Application of the water subtraction algorithm in determining the degree of conversion of self-etching adhesives.

Purpose: This study evaluated the effect of residual water included within the FT-IR spectra on the calculation of the degree of conversion (DC) of a self-etching adhesive (SEA).

Materials And Methods: FT-IR spectra of a SEA (Adper Prompt SE, 3M ESPE) were obtained for different amounts of dentin powder, agitation times, and light-curing times. The measured DC (mDC) obtained from the IR spectra was compared to the apparent DC (aDC) from the adjusted IR spectra using the water subtraction algorithm (WSA), by which the water absorption band was subtracted from the obtained IR spectrum.

The effect of clinical performance on the survival estimates of direct restorations.

Objectives: In most retrospective studies, the clinical performance of restorations had not been considered in survival analysis. This study investigated the effect of including the clinically unacceptable cases according to modified United States Public Health Service (USPHS) criteria into the failed data on the survival analysis of direct restorations as to the longevity and prognostic variables.

Materials And Methods: Nine hundred and sixty-seven direct restorations were evaluated.

Peri-implant bone formation of non-thermal atmospheric pressure plasma-treated zirconia implants with different surface roughness in rabbit tibiae.

Objectives: The aim of this study was to evaluate and compare the osseointegration of powder-injection molded (PIM) zirconia implants in rabbit tibiae with or without He plasma treatment.

Material And Methods: Twenty-five rabbits received 4 types of external hex implants with identical geometry in the tibiae: PIM zirconia implants, roughened PIM zirconia implants, plasma-treated PIM zirconia implants, and plasma-treated roughened PIM zirconia implants. The contact angles of the four types of implants were evaluated.

Effect of the applied power of atmospheric pressure plasma on the adhesion of composite resin to dental ceramic.

Purpose: To evaluate the effect of applied power on dental ceramic bonding of composite resin using nonthermal atmospheric pressure plasma (APP).

Materials And Methods: A pencil-type APP torch was used to modify the surface chemical composition and hydrophilicity of dental ceramic and to improve the adhesion of composite resin to the surface. The effect of the applied power on chemical changes of the plasma polymer on a ceramic surface and the adhesive strength between the composite resin and feldspathic porcelain were examined.

Autotransplantation of teeth with complete root formation: a case series.

Introduction: Autotransplantation is a viable option for treating missing teeth when a donor tooth is available. This retrospective study reports the success rate for the autotransplantation of 19 molars with complete root formation.

Methods: The study enrolled 19 patients (11 men and 8 women) in whom 19 molars were transplanted.

Effects of blood contamination on microtensile bond strength to dentin of three self-etch adhesives.

This study evaluated the effects of blood contamination and decontamination methods during different steps of bonding procedures on the microtensile bond strength of two-step self-etch adhesives to dentin. Sixty extracted human molars were ground flat to expose occlusal dentin. The 60 molars were randomly assigned to three groups, each treated with a different two-step self-etch adhesive: Clearfil SE Bond, AdheSE and Tyrian SPE.