A Case of Anterior Single Tooth Implant with Fractured Zirconia Abutment due to Trauma.

In recent years, a wide variety of materials have been used in dental implant treatment. In selecting the superstructures and abutments to be used it is important to consider their potential effect on the stability and durability of the planned implant. Excessive force applied to an implant during maintenance commonly results in complications, such as fracture of the superstructure or abutment, and loosening or fracture of the screws.

Cyclic Fatigue Properties of Titanium Alloys for Application in Dental Implants.

The present study investigated the cyclic fatigue properties of titanium alloys (Ti-6Al-4V and Ti-6Al-7Nb) as implant materials and compared their properties with those of commercially pure titanium. Ti-6Al-4V and Ti-6Al-7Nb cylinders with diameters of 3.0 mm were examined.

Influence of one-wall remaining coronal tooth with resin abutment and fiber post on static and dynamic fracture resistance.

The objective of this study was to determine the influence of height and thickness of the one wall remaining coronal tooth structure on the fracture resistance of an endodontically treated root with resin abutment build-up using resin composite and fiber-reinforced resin composite post. Static and dynamic fracture tests were performed by placing the remaining tooth wall on the tensile side and applying loads at an angle of 30° from the tooth axis. Superior static fracture resistance was observed when the wall remaining on the tooth had a height and thickness greater than 1.

Effects of 2% sodium fluoride solution on the prevention of streptococcal adhesion to titanium and zirconia surfaces.

Streptococci are associated with dental plaque formation as the early-colonizing bacteria that adhere to titanium (CpTi) and zirconia (TZP) implant abutment surfaces. Effective prevention of peri-implantitis may be possible by removing streptococci as target. This study aimed to evaluate the effects of 2% NaF on the prevention of streptococcal adhesion to CpTi and TZP.

evaluation of a removable partial denture framework using multi-directionally forged titanium.

Purpose: This study evaluated the availability of multi-directionally forged (MDF) titanium (Ti) as a component of removable partial dentures (RPDs). MDF-Ti remarkably improved the mechanical properties of RPDs due to its ultrafine-grained structure.

Materials And Methods: The wear resistance, plaque adhesion, and machinability of MDF-Ti were tested.

Comparison of retentive forces between telescopic crowns made of poly(ether ether ketone) and type 4 gold alloy.

In this study, retentive forces were compared between telescopic crowns (TSC) made with poly(ether ether ketone) (PEEK) using computer-aided design and manufacturing and type 4 gold alloy using the conventional method. The retentive forces of TSCs were evaluated by performing a pull-out test with primary and secondary crowns. Initial retentive force was approximately 12 N for both PEEK and gold alloy TSCs.

Adhesion of streptococci to titanium and zirconia.

The purpose of this study was to evaluate the adherence of streptococci to disks of titanium (commercially pure titanium: CpTi) and zirconia (tetragonal zirconia polycrystals: TZP). CpTi and yttria-stabilized TZP disks with a mirror-polished surface were used as specimens. The arithmetic mean surface roughness (Ra and Sa) and the surface wettability of the experimental specimens were measured.

Low-temperature degradation of high-strength Y-TZP (yttria-stabilized tetragonal zirconia polycrystal).

The objective of this study was to investigate the low temperature degradation characteristics of 2 types of high strength yttria-stabilized tetragonal zirconia polycrystal (Y-TZP) in order to evaluate its suitability for implant body, implant superstructure or abutment. Disk-shaped conventional Y-TZP (0.25 mass% alumina) subjected to hot isostatic press treatment (HIP-Y-TZP) and Y-TZP/4AlO with additional alumina (4.

Applying intraoral scanner to residual ridge in edentulous regions: in vitro evaluation of inter-operator validity to confirm trueness.

Background: The purpose of this study was to investigate the trueness of intraoral scanning of residual ridge in edentulous regions during in vitro evaluation of inter-operator validity.

Methods: Both edentulous maxillary and partially edentulous mandibular models were selected as a simulation model. As reference data, scanning of two models was performed using a dental laboratory scanner (D900, 3Shape A/S).

The characteristic regulation of gene expression Lbp and Sod3 in peri-implant connective tissue of rats.

The aim of this study was to investigate the characteristic gene expression profile and localization of peri-implant connective tissue (PICT) compared with those of periodontal connective tissue (PCT) and oral mucosal connective tissue (OMCT). Upper first molar of 5-week-old rats were extracted and titanium implant were placed for PICT group. PCT and OMCT were used as control.

In vitro wear behavior of restorative resin composites against bovine enamel.

The purpose of this study was to clarify the effects of fabrication method of restorative resin-based composites on its wear using enamel as antagonist teeth. Wear evaluation was performed via two-body wear test using hemispherical samples of restorative resin-based composite (abrader specimen) fabricated through direct restoration method, indirect restoration method, and CAD/CAM, and bovine enamel (substrate specimen). As a result, there was a difference in wear volume between resin-based composite and bovine enamel depending on the fabrication method.

Future prospects of zirconia for oral implants -A review.

Zirconia have been applied to dental implants as well as fixed dental prostheses due to their mechanical, esthetic and biocompatible performance. Moreover, they offer an advantage over titanium (Ti) implants, in that there is no risk of discoloration or hypersensitive reaction with allergy. In this review, the durability and tissue-compatibility of zirconia for the oral implants was mainly discussed.

Change in the retentive force of Akers clasp for zirconia crown by repetitive insertion and removal test.

Purpose: The objective of this study was to evaluate the suitability of monolithic zirconia crowns (MZC) as abutment teeth of Akers clasps on removable partial dentures (RPD) by determining the change in retentive force after repetitive insertion/removal test.

Methods: MZC and silver palladium copper alloy (Ag-Pd) full-metal crowns (FMC) for the mandibular second premolar were fabricated. Resin patterns of Akers clasps made with a 3D printer were casted with Ag-Pd or cobalt chromium alloy (Co-Cr).

Optical properties and flexural strength of translucent zirconia layered with high-translucent zirconia.

This study investigated the optical properties and flexural strength of translucent TZP layered with high-translucent PSZ using resin cement of various shades. Zirconia specimens (translucent TZP; Zpex and high-translucent PSZ; ZpexSmile) were 13 mm in diameter, layered at thickness ratios of 0.3/0.

Accuracy and retention of denture base fabricated by heat curing and additive manufacturing.

Purpose: The aim of the present study was to compare the accuracy and retentive force of an experimental denture base fabricated using additive manufacturing and heat curing.

Methods: A maxillary edentulous jaw model made of silicon was used. The shape data for the working cast and wax pattern of the experimental denture base were obtained using a dental laboratory scanner.

Wear properties of esthetic dental materials against translucent zirconia.

To clarify the influence of translucent tetragonal zirconia polycrystals (TZP) on wear properties of esthetic dental materials, two-body wear test was performed using translucent TZP as abrader specimen, and bovine tooth enamel (BTE), two resin composites including hybrid filler (CRH) and nano filler (CRN), two glass ceramics including leucite reinforced feldspar porcelain (POR) and lithium disilicate (LDC), or translucent TZP as substrate specimen. After the wear test, wear volume were determined from substrate specimen and surface roughness were measured from abrader specimen. In addition, Vickers hardness was measured and surface morphologies were observed after wear test using a scanning electron microscope.

Study on bone quality in the human mandible-Alignment of biological apatite crystallites.

The importance of considering bone quality during oral implant treatment is increasingly being recognized. Assessment of bone quality in response to changes in the jaw bone is extremely important when planning treatment. The present study analyzed biological apatite (BAp) crystallites, a bone quality factor, in order to investigate crystallographic anisotropy in dentate and edentulous human mandibles.

Bone marrow stromal cells from low-turnover osteoporotic mouse model are less sensitive to the osteogenic effects of fluvastatin.

This study aimed to investigate the effects of fluvastatin on the differentiation of bone marrow stromal cells (BMSCs) into osteoblasts in senescence-accelerated mouse prone 6 (SAMP6) compared with that in the normal senescence-accelerated-resistant mouse (SAMR1) model. SAMP strains arose spontaneously from the AKR/J background and display shortened life span and an array of signs of accelerated aging, compared with control SAMR strains. The dose effects of fluvastatin were also evaluated.

Effect of occlusal groove on abutment, crown thickness, and cement-type on fracture load of monolithic zirconia crowns.

The aim of this study was to investigate the effects of occlusal form of abutment, occlusal thickness of monolithic zirconia crowns (MZC), and cement type on the fracture load of MZC. Abutments were prepared with 2 types of occlusal forms: groove-type and flat-type. These were designed so that thickness at the central fissure region of MZC was 0.

Corrosion behavior of titanium in response to sulfides produced by Porphyromonas gingivalis.

Objective: To investigate the effects of sulfides produced by Porphyromonas gingivalis (P. gingivalis) on the corrosion behavior of titanium.

Methods: Commercially pure titanium disks were mirror-polished and immersed in culture medium (BHI), spent medium after culturing P.

Influence of grade and surface topography of commercially pure titanium on fatigue properties.

The objective was to investigate the influence of grade and surface topography of commercially pure titanium (Cp-Ti) on fatigue properties evaluated via staircase method. Cp-Ti grades 2 and 4 were roughened by shot blasting and acid etching, and compared with machined specimens. Yield force under static loading for Cp-Ti grades 2 and 4 were 672±51 and 1,088±93 N for machined and 724±99 and 1,118±96 N for roughened group.

Influence of lyophilization factors and gelatin concentration on pore structures of atelocollagen/gelatin sponge biomaterial.

This study aimed to investigate influences of lyophilization factors and gelatin concentration on pore structures of ACG sponge. ACG sponges of different freezing temperatures (-30, -80 and -196C), freezing times (1, 2 and 24 h), gelatin concentrations (0.6%AC+0.

Release properties of atelocollagen-gelatin complexes as carriers for local administration of fluvastatin.

The aim of this study was to investigate properties of atelocollagen/gelatin complexes (AC/Gel) and their characteristics of sustained statin release, to assess the utility of AC/Gel. AC/Gel were prepared by changing the mixing ratio of AC (0 to 40% of AC). Analysis of spectra of fluvastatin (Flu), gelatin (Gel), and Flu with Gel complex using a Fourier transform-infrared spectrometer indicates that Flu was bound to Gel through a bond involving the carboxyl and amino groups.

Effect of Physicochemical Surface Modifications on Bovine Serum Albumin Adsorption to Tetragonal Zirconia Polycrystal in vitro Through the change of the Zeta Potential.

The technology of physicochemical surface modification is available for enhancing the bioactivity and osseointegration capability of tetragonal zirconia polycrystal (TZP). Hydrophobicity index and electrical charge play important roles in protein adsorption. We previously studied the mechanism underlying the adsorption of bovine serum albumin (BSA) on the surfaces of dental materials and hydroxyapatite in vitro.

Hybrid framework with cobalt-chromium alloy and gold cylinder for implant superstructure: Bond strength and corrosion resistance.

Purpose: The aim of this in vitro study was to evaluate tensile bond strengths and corrosion resistance of CoCr alloys joined with gold cylinder by a soldering system in comparison with the conventional cast-joining system.

Methods: CoCr alloys joined with gold cylinder by a soldering system using a high-fusing gold solder (CoCr/Solder/Gold cylinder), gold alloy joined with gold cylinder by a cast joining system (Gold alloy/Gold cylinder) and CoCr castings were fabricated. The tensile bond strength and corrosion resistance in 0.