Effects of Liner-Bonding of Implant-Supported Glass-Ceramic Crown to Zirconia Abutment on Bond Strength and Fracture Resistance.

This study was conducted to test the hypothesis that heat-bonding with a liner positively affects the bond strength and fracture resistance of an implant-supported glass-ceramic crown bonded to a zirconia abutment produced by a computer-aided design/computer-aided milling (CAD/CAM) procedure. Lithium disilicate-reinforced Amber Mill-Q glass ceramic blocks were bonded to 3 mol% yttria stabilized tetragonal zirconia polycrystal (3Y-TZP) blocks by heat-bonding with a liner or cementation with a dual-cure self-adhesive resin cement for a microtensile bond strength test. CAD/CAM implant-supported glass ceramic crowns were produced using Amber Mill-Q blocks and bonded to a milled 3Y-TZP zirconia abutments by heat-bonding or cementation for a fracture test.

The Principles of Functional and Mucostatic Impressions for Complete Denture Bases: A Review.

In addition to needing to be hygienic and biocompatible, the base of a complete denture (CD) should provide intimate adaptation to the mucosa of a ridge. The ridge form may differ under function than when at rest because of the compressibility of mucosa. This viscoelastic behavior of ridge mucosa has been a focus of research and a clinical challenge confronted by dentists when making impressions.

Impact of implantoplasty on strength of the implant-abutment complex.

Purpose: Implantoplasty, a procedure that is done to smooth contaminated implant surfaces, has been used in the treatment of peri-implantitis. It reduces the implant diameter, which might compromise the implant's strength. This in vitro study was designed to evaluate the effect of implantoplasty on implant strength.

Prosthodontic management of abnormal tooth development secondary to chemoradiotherapy: a clinical report.

Late effects of chemoradiotherapy for childhood cancer treatment include developmental disturbances of the maxillofacial and dentoalveolar structures. Prosthodontic rehabilitation of these patients presents a significant challenge in restoring function, esthetics, and comfort. This clinical report describes the prosthodontic management of a young patient who received chemoradiotherapy for neuroblastoma and subsequently developed tooth abnormalities.

Optimization of maxillary obturator thickness using a double-processing technique.

Preservation of remaining structures is a primary goal of prosthetic rehabilitation. Continuously applied stresses on the remaining tissues from a large, heavy obturator jeopardize the health of the tissues, compromise the function of the prosthesis, and affect patient comfort. Various techniques have been described for hollowing the bulb of an obturator after processing to reduce its weight; however, access to the inner aspects of the bulb is limited, preventing adequate control of thickness of the walls.

Effect of heat treatment on fracture toughness K(IC) and microstructure of a fluorcanasite-based glass-ceramic.

Purpose: The purpose of this study was to test the hypothesis that the increase in fracture toughness of a fluorcanasite-based glass-ceramic is a linear function of crystal volume fraction.

Materials And Methods: A total of 60 specimen bars (20 x 5 x 2 mm(3)) were cut from parent glass blocks, polished, annealed, randomly divided into six groups, nucleated at 680 degrees C/4 hr, and crystallized at the following temperatures and times: (1) 850 degrees C/0.5 hr, (2) 850 degrees C/1 hr, (3) 850 degrees C/3 hr, (4) 750 degrees C/6 hr, (5) 800 degrees C/6 hr, or (6) 850 degrees C/6 hr.

Maxillofacial restoration after head and neck tumor therapy.

Oral and pharyngeal cancers are among the leading cancer sites. Surgery, radiation, chemotherapy, or combination therapies are common treatment modalities. Radiotherapy and chemotherapy cause significant morbidity and long-term irreversible sequelae in the oral cavity.

Dental implant-assisted prosthetic rehabilitation of a patient with a bilateral maxillectomy defect secondary to mucormycosis.

Prosthodontic rehabilitation of patients with bimaxillary resection involving the maxillae, hard and soft palates, and paranasal sinuses presents a significant challenge in restoring speech, deglutition, mastication, and respiration. This clinical report describes the prosthodontic management of a young girl treated for leukemia who required a bilateral maxillectomy secondary to mucormycosis. Distraction osteogenesis, bone grafts, osseointegrated implants, and magnet attachments were used to provide retention, support, and stability of a large definitive obturator.

Effect of post-silanization drying on the bond strength of composite to ceramic.

Statement Of Problem: The temperature reported for thermally treating silanated ceramics to improve composite-ceramic bonding is often too high for chairside applications.

Purpose: This study investigated whether post-silanization drying with a stream of warm air could enhance the composite/ceramic tensile bond.

Material And Methods: Thirty-two ceramic blocks (6 x 6 x 9 mm), 16 of each ceramic, were fabricated and divided into 8 subgroups using 4 roughening procedures and 2 silanization protocols per ceramic (Eris and IPS Empress).

Effect of nucleation temperature on fracture toughness (KIC) of fluorcanasite-based glass-ceramic.

Purpose: The purpose of this study was to test the hypothesis that nucleation temperature significantly affects the fracture toughness of a fluorcanasite-based glass-ceramic.

Materials And Methods: Sixty specimens were cut from a glass bar, polished, and randomly divided into six groups for nucleation treatment at temperatures of (1) 520 degrees C, (2) 550 degrees C, (3) 580 degrees C, (4) 610 degrees C, (5) 640 degrees C, and (6) 670 degrees C for 4 hours and a crystallization temperature of 850 degrees C for 6 hours. A precrack was produced at the center of each bar, and the prepared specimens were subjected to three-point flexural loading with the cracked surface under tension using an Instron machine at a cross-head speed of 0.

Effect of surface topography on the bond strength of a composite to three different types of ceramic.

Statement Of Problem: Mechanical retention based on the surface topography is critical for the success of chairside repair of chipped or fractured ceramic prostheses with a composite.

Purpose: The purpose of this study was to investigate whether the tensile bond strength of a composite to 3 dental ceramics was affected by surface roughening procedures on the ceramics.

Material And Methods: Three ceramics, Eris (ERV), Empress 1 (E1C), and an experimental ceramic (EXC), were used to fabricate 12 rectangular blocks (5 x 5 x 10 mm).

Fracture toughness (K(IC) of a hot-pressed core ceramic based on fractographic analysis of fractured ceramic FPDs.

Purpose: The objective of this study was to test the hypothesis that there is no significant difference between the fracture toughness (K(IC)) of an experimental hot-pressed core ceramic measured by fractographic analysis of failed ceramic prostheses and the values determined by other standard methods.

Materials And Methods: Four groups were subjected to one of four test methods: group 1 = indentation strength technique (standard numerical calculation); group 2 = indentation strength technique (fractographic analysis); group 3 = flexure test of precracked specimens (fractographic analysis); and group 4 = fractographic analysis of failed three-unit fixed partial dentures (FPD). For groups 1 to 3, 20 ceramic bar specimens were subjected to three-point flexure at a cross-head speed of 0.

Wetting characteristic of ceramic to water and adhesive resin.

Statement Of Problem: Maximum wetting of ceramic by adhesive resin is required to achieve optimal adhesion of the resin to ceramic. It is unknown whether the adhesion of the resin to the ceramic is affected by the surface topography and wetting by water or the adhesive resin.

Purpose: This study was designed to characterize the effect of surface topography on the wetting of ceramics by water and adhesive resin.

Effect of connector design on the fracture resistance of all-ceramic fixed partial dentures.

Statement Of Problem: Fracture of all-ceramic fixed partial dentures (FPDs) tends to occur in the connector area.

Purpose: The objective of this study was to test the hypothesis that the radii of curvature at the connector affects the fracture resistance of 3-unit FPDs.

Material And Methods: With the use of a standardized silicone mold, 40 three-unit FPD wax patterns were fabricated with the same dimensions and divided into 4 groups of 10 specimens per group.

Factors affecting enamel and ceramic wear: a literature review.

Enamel wear by ceramics may adversely affect maintenance of the vertical dimension of occlusion and can increase the potential for thermal sensitivity. In this article, factors related to the abrasion of enamel by dental ceramics are critically reviewed. Concepts of physical, microstructural, chemical, and surface characteristics of dental ceramics on wear are presented based on research published since 1950.