Background: In recent years, glass fibres have been used to strengthen denture base resins. A major difficulty in using reinforcing fibres with multiphase acrylic resins, such as powder liquid resins, is inadequate impregnation of the fibres with the resin. Methods: This investigation examined the reinforcing effect of glass fibres on the fracture resistance and flexural strength of acrylic denture base resins. Eighty identical specimens were formed in specially designed moulds in accordance with the manufacturer's recommendations. The four experimental groups were prepared and these consisted of conventional acrylic resin and the same resin reinforced with glass fibres. Ten specimens were fabricated in a standardized fashion for each experimental group. Flexural strength was tested using a 3‐point universal testing machine. Results: In this study, statistically significant differences were found in the flexural strength of the specimens (P<0.05). The injection‐moulded, fibre‐reinforced group had significantly lower flexural strength than the injection‐moulded group (P<0.001), and the microwave‐moulded, fibre‐reinforced group had lower flexural strength than the microwave‐moulded group. The fracture resistance was significantly higher in the injection‐moulded, fibre‐reinforced group than in the injection‐moulded group (P<0.05), and the fracture resistance was significantly higher in the microwave‐moulded, fibre‐reinforced group than in the microwave‐moulded group. Conclusion: Within the limitations of this study, the flexural strength of heat‐polymerized PMMA denture resin was improved after reinforcement with glass fibres. It may be possible to apply these results to distal extension partial and complete denture bases.

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Recently, dental plaque (DP) and saliva have been implicated as possible sources of Helicobacter pylori infection. This subject was studied to investigate the detection rates of H. pylori in the DP and saliva by use of EIA, CLO tests and culture depending on H. pylori infection state of gastric mucosa. H. pylori positive was found in 68.3% (468) by CLO test, 46.4% (318) by EIA and 43% (295) by culture in gastric mucosa samples taken from 685 patients. CLO positive of 468 patients in dental plaque is found from dentate patients 11.1%, edentulous patients 16.23% and saliva from dentate patients 2.77%, edentulous patients 4.05%. H. pylori positive by EIA 318 patients' in dental plaque is found from dentate patients by EIA 9.1%, edentulous patients 14.46% and saliva from dentate patients 1.57%, edentulous patients 0.33%. H. pylori positive by culture 295 patients' in dental plaque is identified from dentate patients by culture 5.42%, edentulous patients 9.15% and saliva from dentate patients 0%, edentulous patients 0.33%. The detection rates of H. pylori in DP (6.9%) were rather low than saliva (28.6%) respectively. About half of the world population is infected with H. pylori, but the transmission and the source of this infection are still unknown.

By means of a pull-out test, this study compared the retentive force of three fiber-reinforced resin composite posts and a zirconia post. These posts were cemented using two different dual-polymerizing adhesive resin luting agents.Forty freshly extracted canines were selected for the study. All tooth root were endodontically treated and the post spaces prepared. The posts were luted using luting agents according to the manufacturers' guidelines. A tensile force was applied, and all data were collected and analyzed statistically. Glass fiber posts that were luted with Panavia F (Group 3) had the highest median load (3.610 N), while zirconia posts that were luted with RelyX ARC (Group 8) had the lowest median load (0.926 N). Among the different post systems that were luted with Rely X ARC, significant differences were observed in their median tensile loads (p<0.047). When comparing between Panavia F and RelyX ARC of each post system, a significantly higher tensile load was seen with zirconia posts luted with Panavia F (Group 7) (p<0.032).