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This article discusses the results of a research study conducted to determine the strength of the adhesive bond between a dental acrylic resin and dentin. The study finds the average tensile strength of the bond to be between 27.4 and 55 kilograms per centimeter squared (kg/cm2) when treated with a combination of N-phenylglycine and glycidyl methacrylate (NPG-GMA).

Dental caries is a common disease on a global scale. Resin composites are the most popular materials to restore caries by bonding to tooth tissues via adhesives. However, multiple factors, such as microleakage and recurrent caries, impair the durability of resinous restorations. Various innovative methods have been applied to develop adhesives with particular functions to tackle these problems, such as incorporating matrix metalloproteinase inhibitors, antibacterial or remineralizing agents into bonding systems, as well as improving the mechanical/chemical properties of adhesives, even combining these methods. This review will sum up the latest achievements in this field. [ABSTRACT FROM AUTHOR]

The authors assessed the strengthening effect of different types of metal inclusion on acrylic resin with special reference to mandibular overdentures. Tests were carried out on four groups of three resin specimens, each 72 x 21 x 4 mm. One group of plain specimens and three with different types of strengtheners were fitted with two matrix Dalbo-Rotex components. Flexion-traction forces were applied in an Instron testing machine, containing an attachment with two corresponding patrix inserts. Full-length cast cobalt-chromium lattice, 0.4 mm in thickness, increased the strength of acrylic resin more than stainless steel 0.8-mm wire of 0.2-mm-thick mesh. However, none of the differences was significant. [ABSTRACT FROM AUTHOR]

The article evaluates new shades of Unifast Light-Cured Acrylic Resin from GC International Corp..

Corrections to captions of figures in the article "In Vitro Study on the Inhibiting Effect of Different Agents on the Growth of Candida Albicans on Acrylic Resin Surfaces," by E. Spiechowicz and colleages in the January 1990 issue including a figure showing the storage of acrylic resin disks contaminated with C albicans in nystatin, another showing their storage in chlorhexidine, and other showing their storage in poly-L-histidine are presented.

Background: There are a large number of composite resin restorative materials and acrylic resin denture base materials. Brushing procedures exposes them to wear. The objective was to evaluate the changes in surface roughness of 2 types of composite resin restorative materials and 4 acrylic resin denture base materials after simulated tooth brushing. Material and methods: Twenty specimens of composite resin materials (self-cure and light-cure) and seventy specimens of denture base materials (heat-cure, lightcure acrylates and acetal) were fabricated according to the manufacturer s instructions. The specimens were subjected to a custommade tooth brushing simulation device applying a force of 2N. Toothpaste slurry and water was used for the brushing procedures. Surface roughness before and after simulated tooth brushing was measured with a profilometer (Surtronic 25). Data were statistically analyzed using dependent t-tests. Results: All the materials showed changes in surface roughness. Light-cure composite resin showed significant changes in surface roughness, while the self-cure composite was more resistant to wear. Among the denture base materials the heat-cure acrylic resin showed the most significant changes and acetal resin base material was the most resistant. Conclusions: Surface changes of dental materials depended on their physical and chemical properties and the cleaning procedure. Within the limitation of this study the following could be concluded: self-cure composite was the most resistant to surface changes; the "medium" labeled toothbrush caused significant changes without using toothpaste on the surface of the light-cure composite and the heat-cure acrylic resin materials. Further studies are planned to evaluate other types of composite and acrylic resin materials using different types of toothpastes and brushes. [ABSTRACT FROM AUTHOR]

The article discusses the problem of cumulative damage of teeth in elderly people and the Class II composite restorations treatment for the problem. Topics discussed include use of amalgam as standard direct restorative material for the patients, introduction of Bowen resin and the acid-etch technique restoration technique for teeth restoration, and advantages and disadvantages of the standard Class II composite restoration in elderly patients.

The article offers suggestions for reactivation of Haas Expansion screw, a tooth expander used for palatal expansion of teeth. It is instructed that after expanding the screw up to 75 percent place acrylic resin on both sides of the screw and press it firmly for proper relocation. It is further informed that reactivation of the screw is also required after the resin has polymerized and cover the area with composite bar.

The article examines growth in the temporary dental implant industry. Benefits and drawbacks of dental implant materials including acrylic, bis-acryl composite resin, and polymethyl methacrylate are considered and the alleged benefits of temporary implants for dental patients are reviewed including prevention of bacterial infection and preservation of tooth position.

This article focuses on hypersensitivity from dental acrylates in a patient previously sensitized to artificial nails. A 63-year-old female patient planned to restore her teeth. A temporary crown composed of dimethacrylates and mono-, di-, triglycerin- dimethacrylate-phosphates was fabricated. The night after this intervention the patient experienced painful blisters, oral erythema and oedema of the inner lip on the adjacent mucosa. The symptoms aggravated severely and she visited her dentist 2 days after the second intervention. The dentist prescribed oral corticosteroids that gave only partial relief. The patient has been wearing for years artificial fingernails of the acrylic type without complaints. However when questioned she admitted having had an eczematous reaction to sculptured nails of the photobonded type 3 years before.

The author discusses research in restorative dentistry. He discusses how restorative dentistry has led to innovations in materials such as dental acrylics but comments that there is too much focus on evaluating restorative materials and methods. He notes the lack of personnel conducting scientific research in the restorative dentistry disciplines and suggests that dentistry problems requiring scientific research should be used to illustrate the need for more research.

Dental hypersensitivity due to exposure of dentinal tubules under the enamel layer to saliva is a very popular and highly elusive technology priority in dentistry. Blocking water flow within exposed dentinal tubules is a key principle for curing dental hypersensitivity. Some salts used in 'at home' solutions remineralize the tubules inside by concentrating saliva ingredients. An 'in-office' option of applying dense resin sealants on the tubule entrance has only localized effects on well-defined sore spots. We report a self-assembled film that was formed by facile, rapid (4 min), and efficient (approximately 0.5 g/L concentration) dip-coating of teeth in an aqueous solution containing a tannic acid-iron(III) complex. It quickly and effectively occluded the dentinal tubules of human teeth. It withstood intense tooth brushing and induced hydroxyapatite remineralisation within the dentinal tubules. This strategy holds great promise for future applications as an effective and user-friendly desensitizer for managing dental hypersensitivity. [ABSTRACT FROM AUTHOR]

This article discusses the results of a research study conducted to determine the presence of ethylene glycol dimethacrylate (EGDM) in acrylic denture base resins. Seven monomers were examined using gas-liquid chromatography and infrared analysis. The study concludes that the monomers consist mostly of methyl methacrylate.

The article evaluates several orthodontic equipment and supplies including Biocryl ICE acrylic resin from Great Lakes Orthodontics Ltd., SnapLink reconvertible tube from Ormco Corp., and MultiMotion patient headrest from Sirona Dental Systems Inc.

The article offers an overview of several studies on prosthodontics published in the "Journal of Prosthodontics" in 2007. A study by K. X. Michalakis et al compared the hydrophilic properties of several impression materials. Research by E. S. Reddy et al assessed the surface roughness of cast commercially pure titanium after finishing and polishing with different materials. The effect of long-term water immersion on the shear bond strength between reline and denture base acrylic resins is investigated by A. Azevedo et al.

This article reports that the Vita Physiodens is a premium acrylic tooth which in its shape and size is identical with the average design of natural teeth, Vita clams. The anteriors have a smooth transition from the tooth crown towards the tooth neck which supports the natural design of papillae and gingivae while individual incisal edges enhance the appearance of the tooth. The Vita Physiodens tooth is available in the systems Vita System 3D-Master, 26 shades and Vitapan classical, 15 shades.

The article reports on the results of research which was conducted in an effort to evaluate an automated centrifuge that casts a pour denture base resin into a colloidal mold and then automatically cycles pressure and heat to cure it. Researchers found that dentures processed from pour resins with a centrifuge compared favorably with those produced without centrifugation and that the negligible clinical shrinkage found with either technique was clinically insignificant. They also found that both techniques can be related to the development of overclosure in clinical dentures

The article reports on the results of research which was conducted in an effort to investigate the quantitative characterization of the microstructure of a typical cold curing dental resin which was designed for the repair of denture bases. Researchers took resin samples and polished them with the use of standard metallographic procedures. They found that cold curing resins contain about 2% residual monomer and that this would influence particle size.

The article presents a study which examined the use of radioactive tracers in determining the protective effects of dental cavity liners. The study used tritium in the monomer of self-curing acrylic filling materials in monkey teeth. The author considers the irritating effects of materials which penetrate through dental liners.