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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Nicotine is associated with increased incidence of periodontal disease and poor response to therapy. This article aimed at identifying the expression of Matrix metalloproteinases-2 (MMP2) and Vascular endothelial growth factor (VEGF) proteins on extracellular matrix, fibrous distribution and angiogenetic development in periodontitis caused by nicotine effects on periodontal membrane. In this experimental study, the groups were divided into nicotine and control groups. While the nicotine groups in rats (n=6) were administered 2mg/kg Nicotine sulphate for 28 days, the control group in rats (n=6) were only administered 1,5 ml physiologic saline solution subcutaneously for 28 days. Histological sections were prepared and immunohistochemically stained for MMP2 and VEGF. The sections were stained with Trichrome-Masson were observed under light microscope. VEGF and MMP2 immunoreactivity of periodontal gingiva and dentin was assessed by immunohistochemical staining. In conclusion, nicotine effect reduces Matrix metalloproteinases production and disrupt collagen synthesis and causes periodontitis. We observed that nicotine increases periodontitis by disrupting periodontal membrane and prevent tooth to anchor in dental alveoli by disrupting epithelial structure.

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.

Most patients prefer fixed dentures, even in the presence of uni and bilateral free-end saddle. The most suitable treatment for this is an implant or implant-supported prosthetic restoration. A combined prosthetic and orthodontic treatment with distalization of a posterior tooth towards the edentulous region is an alternative approach. This study involved a 34.3 year old female patient who had a free-end edentulous space on the left mandibula and missing 1st and 3rd molars on the right mandibula. The patient was offered both a removable partial denture and implant treatment options. A detailed explanation of her situation and suitable treatments were given but she refused both options. Therefore, an alternative combined treatment involving prosthodontic and orthodontic disciplines was performed. The second premolar tooth was distalized orthodontically and used as a distal bridge abutment. After 65 months, prosthetic restoration was functional and abutment teeth and periodontium were pathology free, and the patient was satisfied with the results.