Effect of surface treatments on microtensile bond strength of repaired aged silorane resin composite.

Objective: This laboratory study compared the repaired microtensile bond strengths of aged silorane resin composite using different surface treatments and either silorane or methacrylate resin composite.

Methods: One hundred eight silorane resin composite blocks (Filtek LS) were fabricated and aged by thermocycling between 8°C and 48°C (5000 cycles). A control (solid resin composite) and four surface treatment groups (no treatment, acid treatment, aluminum oxide sandblasting, and diamond bur abrasion) were tested (N=12 blocks, 108 beams/group).

Fracture resistance and fracture resistance after fatigue loading of 4 different post and cores in endodontically treated teeth.

This article discusses the fracture resistance of 4 post and core systems including a combined obturator/post system before and after fatigue loading. The obturator/post demonstrated the highest fracture resistance values. The use of a combined obturator/post with a single resin endodontic sealer/luting cement seems promising.

Effects of coupling methods on galvanic corrosion behavior of commercially pure titanium with dental precious alloys.

Background: When a dissimilar couple is exposed to corrosive environment, it will normally exhibit a galvanic corrosion. The galvanic corrosion might be influenced by various factors, including type and concentration of electrolyte, surface area ratio between anode and cathode, type of coupling material, and coupling manner.

Purpose: The purpose of this study was to investigate and compare the galvanic corrosion behavior of commercially pure titanium when coupled with type IV Au alloy, Au-Ag-Pt alloy, and Ag-Au-Pd alloy by different coupling methods.

Reinforcement of acrylic resins for provisional fixed restorations. Part III: effects of addition of titania and zirconia mixtures on some mechanical and physical properties.

Acrylic resins have been used in many different applications in dentistry, especially in the fabrication of provisional fixed partial dentures. Ideally, a provisional crown and bridge material should be easy to handle and should protect teeth against physical, chemical, and thermal injuries. Some of the problems associated with this use are related to the material's poor mechanical properties.

Dimensional accuracy of dental casts: influence of tray material, impression material, and time.

Purpose: This study evaluated the influence on dimensional accuracy of dental casts made with different types of trays and impression materials and poured at different and multiple times.

Materials And Methods: Two types of stock trays (plastic stock tray, perforated metal stock tray) and 4 types of custom tray materials (autopolymerizing acrylic resin, thermoplastic resin, and 2 types of light-polymerized acrylic resins) were used with 2 types of impression materials (addition polymerizing silicone and polyether), to make impressions of a metal master model. Each tray and impression material was used to make 5 impressions.

Management of anterior spacing with orthodontics and prosthodontics.

Closing maxillary and mandibular diastemas is facilitated by a multidisciplinary approach involving orthodontics and prosthodontics. This case study demonstrates the management of a discrepancy in maxillary and mandibular anterior tooth widths. The problem is resolved by limited orthodontic treatment followed by porcelain laminate veneers.

Titanium-porcelain system. Part III: effects of surface modification on bond strengths.

During its development, titanium was found to be incompatible with conventional dental porcelains due to weak bond strength brought about by titanium's high yet oxidative nature. In spite of the development of new low-fusing porcelains designed for titanium application, previous studies have shown that sandblasting pre-treatment prior to porcelain application led to weakening of the metal-ceramic bonding. The aim of this study is to search for an effective alternative to sandblasting for the surface treatment of the titanium substrate in the titanium-porcelain system.

Electrochemical corrosion of titanium and titanium-based alloys.

Statement Of Problem: Two varieties of unalloyed titanium, Ti-6Al-4V and NiTi, commonly are used in medical and dental fields. Several other types of alloys for potential use in these fields have been developed, including Ti-4.5Al-3V-2Mo-2Fe and vanadium-free alloys (Ti-5Al-2.

X-linked (recessive) hypomaturation amelogenesis imperfecta: a prosthodontic, genetic, and histopathologic report.

A 16-year-old white girl requested esthetic restorations for her teeth. She was a manifesting heterozygote for the X-linked recessive form of amelogenesis imperfecta with hypomaturation defect. Lyonization theory states that in the somatic cells of female mammals, one of the two X chromosomes is randomly inactivated early in development.

Bonding strengths of etched porcelain discs and three different bonding agents.

Forty porcelain disks were resin bonded to etched base metal surfaces to measure tensile bond strengths. One metal surface was bonded to each porcelain surface, making each test specimen "sandwiched", with a porcelain disk between two metal surfaces. The mean bond strength values of the Conclude group was 3017 +/- 869 psi.

Marginal fit of direct temporary crowns.

This study compared the effect that shrinkage of four brands of temporary crown and fixed partial denture resins has on the marginal fit of crowns made from them. Under the conditions of this study, crowns made from Coldpac had marginal discrepancies approximately four times larger than those made from Scutan. Crowns made from Snap and Trim had marginal discrepancies approximately two times larger than those made from Scutan.