Influence of polymerization method, curing process, and length of time of storage in water on the residual methyl methacrylate content in dental acrylic resins

This study compared the influence of different polymerization methods (heat, auto-, and microwave energy), different curing processes (in the case of heat- and autopolymerized specimens), and length of storage of the polymerized specimens in distilled water at 37 degrees C on the residual mnethyl methacrylate (MMA) content in dental acrylic resin specimens. Residual MMA of 120 resin specimens were measured using high-performance liquid chromatography. For the heat-polymerized resins, the lowest residual MMA content was obtained when they were given a long-term terminal boil and then stored in the distilled water for at least I day. For the autopolymerized resins, the lowest residual MMA content was obtained when they were additionally cured in water at 60 degrees C and then stored in the distilled water at least I day. For the microwave-polymerized resins, the lowest residual MMA content was obtained when they were stored in the distilled water at least I month. The lowest overall residual MMA content was obtained from heat-polymerized specimens that were given a long-term terminal boil cure and then stored in the distilled water at least 1 day. Different polymerization methods and curing processes have different effects on residual MMA content. It is thus shown that storing a dental acrylic resin specimen in distilled water at 37 degrees C is a simple but effective method of reducing its residual MMA content. (c) 2005 Wiley Periodicals, Inc

Effects of water storage of e-glass fiber reinforced denture base polymers on residual methyl methacrylate content

This study investigated the effect of water storage on residual methyl methacrylate (MMA) content of continuous E-glass fiber (Wetrotex International) reinforced denture base polymers. Heat-polymerization (short- and long-term boiling and conventional curing cycle using Meliodent(TM)), autopolymerization (processed in air at room temperature and in water at 60degreesC with the use of Meliodent Rapid Repair(TM)), and microwave-polymerization (3 min at 500 W with the use of Acron MC(TM)) were employed. The residual MMA contents of 120 specimens were analyzed by high-performance liquid chromatography at deflasking (control) and after water (37degreesC) storage of 1 day, 1 week, and 1 month. Bonferroni's pairwise comparison test was used for statistical analysis. Significant reduction were determined only in the long-term terminal boiled heat-polymerized test group at the end of 1 day (p 0.05). The polymerization methods and cycles applied to the glass fiber reinforced denture base polymers influence both the content and the reduction of residual MMA after water storage. (C) 2004 Wiley Periodicals, Inc

A comparative in vitro evaluation of two different magnetic devices detecting the stability of osseo-integrated implants

Geckili O, Bilhan H, Cilingir A, Mumcu E, Bural C. A comparative in vitro evaluation of two different magnetic devices detecting the stability of osseo-integrated implants. J Periodont Res 2012; 47: 508513. (c) 2012 John Wiley & Sons A/S Background and Objective: It is unknown whether the resonance frequency analysis (RFA) measurements made by two different magnetic resonance frequency analysers are comparable. This in vitro study was designed to compare the RFA measurements made by the two magnetic resonance frequency analysers and to evaluate the intra- and interobserver reliability of the magnetic devices. Material and Methods: Thirty-two implants were placed in four cow ribs. The RFA value of each implant was measured by five different examiners. The measurements were repeated five times, in both the buccal and mesial directions, for each implant at 2 h intervals, and the averages of registered implant stability quotient (ISQ) units were recorded as the buccal ISQ value and the mesial ISQ value for every implant. Results: No statistically significant differences (p > 0.05) were observed between the RFA measurements made by the two magnetic devices. The intra-observer reliability of both devices was excellent, whereas the interobserver reliability of the devices was poor. Conclusion: The results of the RFA measurements of both tested devices overlap. Although both devices show excellent intra-observer reliability, there are variations between the measurements of different examiners

Fever of unknown origin: large vessel vasculitis diagnosed by PET/CT

PET/CT is starting to play an important role in evaluating fever of unknown origin (FUO), due to its ability to localize and delineate areas of high metabolic activity, such as neoplastic proliferation and inflammation, including vasculitis. We present a case of giant cell arteritis (GCA) in a 72-year-old female patient admitted to our department with a 4-month history of FUO, weight loss and fatigue, without specific symptoms or signs. Laboratory investigations suggested acute phase response, with a pronounced erythrocyte sedimentation rate, high CRP level and microcytic anemia. A thorough diagnostic evaluation was performed to exclude an unknown primary tumor, which was initially suspected due to a positive family history of cancer. Surprisingly, PET/CT revealed large vessel vasculitis affecting the ascending, descending and abdominal aorta, as well as subclavian, proximal brachial and carotid arteries bilaterally. Biopsy of the superficial temporal artery confirmed the diagnosis of GCA. Treatment with methylprednisolone and azathioprine led to resolution of clinical symptoms and normalization of laboratory parameters. In addition to the use of PET/CT in the evaluation of FUO, its value as a method complementary to temporal artery biopsy is also discussed

Cytokine gene polymorphism in denture stomatitis patients: A clinical study

ObjectiveThis clinical study investigated the association between cytokine gene polymorphism and Candida growth in denture stomatitis (DS) patients

Cytokine gene polymorphism in denture stomatitis patients: A clinical study

ObjectiveThis clinical study investigated the association between cytokine gene polymorphism and Candida growth in denture stomatitis (DS) patients

Evaluation of periodontal parameters in patients undergoing peritoneal dialysis or hemodialysis

OBJECTIVE: To analyze and compare periodontal parameters in chronic renal failure (CRF) patients undergoing peritoneal dialysis (PD) therapy with a group of patients on hemodialysis (HD) treatment and healthy controls (C)

Dental and periodontal findings in hemodialysis patients

Objective: Oral health problems of chronic renal failure patients can compromise systemic health. This study compared the periodontal and dental health status of patients on hemodialysis (HD) with healthy controls (C)

Dental and periodontal findings in hemodialysis patients

Objective: Oral health problems of chronic renal failure patients can compromise systemic health. This study compared the periodontal and dental health status of patients on hemodialysis (HD) with healthy controls (C)