1.The effect of repeated porcelain firings on corrosion resistance of different dental alloys.
Ali Riza TUNCDEMIR ; Ismail KARAHAN ; Serdar POLAT ; Meral Arslan MALKOC ; Mehmet DALKIZ
The Journal of Advanced Prosthodontics 2013;5(1):44-50
PURPOSE: The aim of this study was to evaluate the effects of repeated porcelain firing process on the corrosion rates of the dental alloys. MATERIALS AND METHODS: Cr-Co, Cr-Ni and Pd-Ag alloys were used for this study. Each metal supported porcelain consisted of 30 specimens of 10 for 7, 9 and 11 firing each. Disc-shaped specimens 10 mm diameter and 3 mm thickness were formed by melting alloys with a propane-oxygen flame and casted with a centrifuge casting machine and then with the porcelain veneer fired onto the metal alloys. Corrosion tests were performed in quintuplicate for each alloy (after repeated porcelain firing) in Fusayama artificial saliva solution (pH = 5) in a low thermal-expansion borosilicate glass cell. Tamhane and Sheffe test was used to compare corrosion differences in the results after repeated firings and among 7, 9 and 11 firing for each alloy. The probability level for statistical significance was set at alpha=0.05. RESULTS: The corrosion resistance was higher (30 mV), in case of 7 times firing (Commercial). On the other hand, it was lower in case of 11 times firing (5 mV) (P<.05). CONCLUSION: Repeated firings decreased corrosion resistance of Pd-Ag, Cr-Co and Cr-Ni alloys. The Pd-Ag alloy exhibited little corrosion in in vitro tests. The Cr-Ni alloy exhibited higher corrosion resistance than Cr-Co alloys in in vitro tests.
Alloys
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Corrosion
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Dental Alloys
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Dental Porcelain
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Fires
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Freezing
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Glass
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Hand
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Saliva, Artificial
2.Effect of Hippophae rhamnoides Extract on Oxidative Oropharyngeal Mucosal Damage Induced in Rats Using Methotrexate.
Ertugrul ERHAN ; Suat TERZI ; Metin CELIKER ; Oguzhan YARALI ; Murat CANKAYA ; Ferda Keskin CIMEN ; Ismail MALKOC ; Bahadir SULEYMAN
Clinical and Experimental Otorhinolaryngology 2017;10(2):181-187
OBJECTIVES: The objective of this study is to investigate and evaluate the effect of Hippophae rhamnoides extract (HRE) on oropharyngeal mucositis induced in rats with methotrexate (MTX) through biochemical, gene expression, and histopathological examinations. METHODS: Experimental animals were divided into a healthy group (HG), a HRE+MTX (HREM) group, HRE group (HREG), and a control group that received MTX (MTXG). The HREM and HREG groups of rats was administered 50 mg/kg HRE, while the MTXG and HG groups were given an equal volume distilled water with gavage. Then, the HREM and MTXG rat groups were given oral MTX at a dose of 5 mg/kg 1 hour after HRE and distilled water was administered. This procedure was repeated for 1 month. At the end of this period, all of the animals were sacrificed with a high dose of anesthesia. Then, the amounts of malondialdehyde (MDA) and total glutathione (tGSH) were determined in the removed oropharyngeal tissues. Interleukin-1β (IL-1β) and tumor necrosis factor-α (TNF-α) gene expressions were measured, and all the tissues were studied histopathologically. RESULTS: The amount of MDA was significantly increased in the MTXG group compared to the HREM, HREG, and HG groups (P<0.001). MTX significantly decreased the amount of tGSH in the MTXG group compared to the HREM, HREG, and HG groups (P<0.001). In this study, there were no visible ulcers in the animal group in which the levels of MDA, IL-1β, and TNF-α were high and the level of tGSH was low. However, histopathologic examination revealed mucin pools in wide areas due to ruptured oropharynx glands, and proliferated, dilated, and congested blood vessels and dilated ductal structures in some areas. CONCLUSION: HRE protected oropharyngeal oxidative damage induced by MTX. As an inexpensive and natural product, HRE has important advantages in the prevention of oropharyngeal damage induced by MTX.
Anesthesia
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Animals
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Blood Vessels
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Estrogens, Conjugated (USP)
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Gene Expression
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Glutathione
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Hippophae*
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Malondialdehyde
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Methotrexate*
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Mucins
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Mucositis
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Necrosis
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Oropharynx
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Rats*
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Stomatitis
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Ulcer
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Water
3.Effect of lutein on methotrexate-induced oxidative lung damage in rats: a biochemical and histopathological assessment
Renad MAMMADOV ; Bahadir SULEYMAN ; Selcuk AKTURAN ; Ferda Keskin CIMEN ; Nezahat KURT ; Zeynep SULEYMAN ; Ismail MALKOC
The Korean Journal of Internal Medicine 2019;34(6):1279-1286
BACKGROUND/AIMS:
This study aimed to investigate the effect of lutein on methotrexate (MTX)-induced pulmonary toxicity in rats biochemically and histopathologically.
METHODS:
The rats in the MTX + lutein (MTXL, n = 6) group were given 1 mg/kg of lutein orally. A 0.9% NaCl solution was administered orally to the MTX (n = 6) group and the healthy group (HG, n = 6). One hour later, a single 20 mg/kg dose of MTX was injected intraperitoneally in the MTXL and MTX. Lutein or 0.9% NaCl solution was administered once a day for 5 days. At the end of this period, malondialdehyde (MDA), myeloperoxidase (MPO), total glutathione (tGSH), interleukin 1 beta (IL-1β), and tumor necrosis factor alpha (TNF-α) were measured in the lung tissues from the animals euthanized with 50 mg/kg thiopental sodium anesthesia. Subsequently, histopathological examinations were performed.
RESULTS:
The levels of MDA, MPO, IL-1β, and TNF-α in the lung tissue of the MTX were significantly higher than those of the MTXL and HG groups (p < 0.0001), and the amount of tGSH was lower. The histopathological findings in the MTX group, in which the oxidants and cytokines were higher, were more severe.
CONCLUSIONS
Lutein prevented the MTX-induced oxidative lung damage biochemically and histopathologically. This result indicates that lutein may be useful in the treatment of MTX-induced lung damage.
4.Surgical treatment of nail bed subungual exostosis.
Melih MALKOC ; Ozgur KORKMAZ ; Mert KESKINBORA ; Ali SEKER ; Ismail OLTULU ; Ahmet Murat BULBUL ; Ferhat SAY ; Aslı CAKIR
Singapore medical journal 2016;57(11):630-633
INTRODUCTIONA subungual exostosis (SE) is a bony overgrowth that is permanently attached to the tip of the distal phalanx. Its pathology differs from osteocartilaginous exostoses in that it mainly involves the overgrowth of normal bone, which may present beneath the toenail or on the sides of the toe. This retrospective study aimed to report the results of surgical treatment when the diagnosis of SE was delayed; the condition was initially considered to be another pathology affecting a different nail or the terminal toe.
METHODSA total of 17 patients (12 female, five male) were included in the study. All surgical resections were performed by the same surgeon using the same surgical technique, with the patient under digital anaesthesia. The patients were evaluated pre- and postoperatively (on Weeks 1 and 6, the first year, and the last follow-up visit) using the American Orthopaedic Foot and Ankle Society questionnaire and the Visual Analogue Scale score.
RESULTSThe patients underwent surgery for SE removal between December 2009 and October 2012. Their mean age was 21.3 ± 4.4 (range 14-29) years and the mean follow-up period was 27.1 ± 7.8 (range 18-45) months. Clinical or radiological recurrence was not observed in any of the patients during the follow-up period. Four patients had superficial infections, which were treated using appropriate antibiotic therapies.
CONCLUSIONAs SE is an uncommon benign lesion, its diagnosis may be delayed. Radiography may be useful in obtaining a differential diagnosis.
Adolescent ; Adult ; Bone Neoplasms ; diagnostic imaging ; surgery ; Cartilage ; diagnostic imaging ; surgery ; Diagnosis, Differential ; Exostoses ; diagnostic imaging ; surgery ; Female ; Humans ; Male ; Middle Aged ; Nail Diseases ; diagnostic imaging ; surgery ; Nails ; surgery ; Orthopedics ; methods ; Pain Measurement ; Postoperative Period ; Recurrence ; Retrospective Studies ; Surveys and Questionnaires ; Young Adult