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Akademisyen Yayinevi yoneticileri, yaklasik 30 yillik yayin tecrubesini, kendi tuzel kisiliklerine aktararak uzun zamandan beri, ticari faaliyetlerini surdurmektedir. Anilan sure icinde, basta saglik ve sosyal bilimler, kulturel ve sanatsal konular dahil 1000 kitabi yayimlamanin gururu icindedir. Uluslararasi yayinevi olmanin alt yapisini tamamlayan Akademisyen, Turkce ve yabanci dillerde yayin yapmanin yaninda, kuresel bir marka yaratmanin pesindedir.Bilimsel ve dusunsel calismalarin kalici belgeleri sayilan kitaplar, bilgi kayit ortami olarak yuzlerce yilin taniklaridir. Matbaanin icadiyla varolusunu saglam temellere oturtan kitabin gelecegi, her ne kadar yeni buluslarin yorungesine tasinmis olsa da, daha uzun sure hayatimizda yer edinecegi muhakkaktir.

Objective To investigate cytotoxic and genotoxic effects of static magnetic field (SMF) produced by dental magnetic attachments on human gingival fibroblasts in vitro. Background Magnetic attachments have numerous roles in dental prosthesis fixation, but few reports evaluate possible biological effects of static magnetic field (SMF) on human gingival tissues, particular genotoxic effects. Materials and methods The Dyna (500-gr breakaway force) and Steco (173-gr breakaway force) dental magnetic attachments were embedded into autopolymerising acrylic resin in four different configurations each, including single and double magnets. Gingival biopsy was performed on 28 individuals during third molar extraction, and each sample was divided into two pieces for culture under SMF exposure or as a control. In total, seven test and seven control gingival fibroblast cultures were performed for each group resulting in 56 gingival fibroblast cultures. The test culture flasks were placed atop the magnet-embedded resin blocks. After cultures were terminated, mitotic index (MI) and micronucleus (MN) rates were analysed at a p = 0.05 significance level by Wilcoxon's test; intergroup differences were analysed with a Kruskal–Wallis test. Results There was no significant difference in intragroup or intergroup MI rates. The double Dyna (p = 0.023) and double Steco (p = 0.016) groups had statistically significant intragroup differences in the MN rates. There were no statistically significant differences in MN rates in intergroup analyses. Conclusion In particular, higher magnetic fields from dental magnetic attachments might be toxic genetically to human gingival fibroblasts. However, there is need for further investigations from different aspects to detect any genotoxicity.

Purpose: The aim of this study was to measure the in vitro retention force of double conical crowns fabricated using primary galvanoforming and secondary casting techniques and those fabricated using primary casting and secondary galvanoforming techniques under simulated clinical conditions before and after a wear test. Materials and Methods: Primary galvanoformed crowns (n = 10) with non-noble secondary crowns (n = 10; group A) and primary non-noble crowns (n = 10) with secondary galvanoformed crowns (n = 10; group B) were fabricated. Each primary and secondary crown was embedded in acrylic resin and weighed with a digital balance. Retention forces were then measured using a universal testing device. To simulate wear, specimens were inserted and separated horizonatally 3285 times in wear equipment with artificial saliva. Retention forces and weights of the double crowns were then remeasured. Data were analyzed using paired t-tests and Wilcoxon tests, and the groups were compared using Mann–Whitney U-tests. Results: In group A, the wear test had a significant influence on the retentive force (p 0.05). In group B, the wear test had a significant influence on the retentive force (p < 0.05), and wear produced a significant difference in weight (p < 0.05). Conclusions: The results of this study indicated that the use of different combinations of galvanoforming and casting techniques in the fabrication of conical crowns significantly affected retention force.

Aim: In order to improve the mechanical properties of polymethyl methacrylate (PMMA), more attention has been directed toward the glass fibers due to its good reinforcement capability. The purpose of this study was to determine the effect of glass fibers on the bond strength between reinforced acrylic resin and components of removable partial denture (RPD). Materials and Methods: Two types of denture teeth (conventional resin and cross-linked resin), two types of framework alloys (CoCr and Ti6Al4V) and heat-polymerized acrylic resin that was not reinforced and reinforced with glass fiber content of 1% and 5% were used. Reinforced and unreinforced acrylic resins were applied to both denture tooth and framework alloy samples to construct bonding area as 5 mm diameter. After polymerization of acrylic resin, samples were stored in distilled water for 2 days at 37°C; then they were thermocycled 5000 times (5-55°C). To record shear bond strength of samples, universal testing machine was used until failure occurred. The shear bond strength data were analyzed at 5% significance level. Results: The shear bond strength of CoCr alloy and cross-linked resin denture tooth samples didn't show any effect with reinforcement. But conventional resin denture teeth bonding enhanced with 5% fiber concentration; and Ti6Al4V, the addition of glass fiber, regardless of the ratio, affected the bonding strength in a positive way. Conclusions: Glass fiber reinforcement of the PMMA increased or did not aAQ4ffect, but never decreased the bonding strength between acrylic resin and component of RPD.

PURPOSE. This study was to evaluate the effect of grinding of the inner metal surface during the porcelain try-in stage on metal-porcelain bonding considering the maximum temperature and the vibration of samples. MATERIALS AND METHODS. Ninety-one square prism-shaped (1 x 1 x 1.5 mm) nickel-chrome cast frameworks 0.3 mm thick were prepared. Porcelain was applied on two opposite outer axial surfaces of the frameworks. The grinding was performed from the opposite axial sides of the inner metal surfaces with a low-speed handpiece with two types of burs (diamond, tungsten-carbide) under three grinding forces (3.5 N, 7 N, 14 N) and at two durations (5 seconds, 10 seconds). The shear bond strength (SBS) test was performed with universal testing machine. Statistical analyzes were performed at 5% significance level. RESULTS. The samples subjected to grinding under 3.5 N showed higher SBS values than those exposed to grinding under 7 N and 14 N (P.05). The types of bur (P=.965) and the duration (P=.679) did not affect the SBS values. On the other hand, type of bur, force applied, and duration of the grinding affected the maximum temperatures of the samples, whereas the maximum vibration was affected only by the type of bur (P

WOS: 000325843200003, Background/purpose: Several all-ceramic materials have been developed to meet the most challenging requirements in restorative dentistry. However, only limited reports have focused on the issue of biocompatibility of all-ceramics. The purpose of this study was to evaluate the effects of different types of all-ceramic substructural materials to determine their biological performance under experimental conditions. Materials and methods: We tested six all-ceramic systems [glass-infiltrated alumina-reinforced ceramic (In-Ceram Alumina, Turkom Cera), glass-infiltrated zirconia-toughened alumina ceramic (In-Ceram Zirconia), low-fusing ceramic (Finesse), yttria-stabilized tetragonal zirconia ceramic (Zirkonzahn), and lithium disilicate glass ceramic (IPS e.max)] using a tetrazolium assay prior to and 3 days after aging, to determine their ability to alter cellular mitochondrial dehydrogenase activity. Mann-Whitney U test and Wilcoxon t test were used for statistical analysis (alpha = 0.05). Results: According to the results of the 3-(4,5-dimethyl-thiazol-2yl-)-2,5-diphenyl tetrazolium bromide tests, the toxic effects of Finesse and Zirkonzahn were statistically insignificant (P > 0.05) compared with the negative control group. In contrast, In-Ceram Alumina, In-Ceram Zirconia, Turkom Cera, and IPS e.max demonstrated statistically significant toxic effects (P < 0.05) compared to the negative control group. When effects of aging on cytotoxic properties were evaluated, In-Ceram Zirconia and Turkom Cera showed increased cytotoxic effects on the 1st day following the aging process, whereas IPS e.max and Zirkonzahn displayed cytotoxic effects on the 2nd day and Day 7, respectively. The cytotoxic effect of;Zirkonzahn and IPS e.max was decreased on the 1st day and at the 2nd week, respectively. Conclusion: Several types of all-ceramic substructures did not cause the same in vitro. responses. Finesse and Zirkonzahn did not carry high biologic risk. However, our results suggest that In-Ceram Alumina, In-Ceram Zirconia, Turkom Cera, and IPS e.max should not be considered as entirely biocompatible materials. Copyright (C) 2012, Association for Dental Sciences of the Republic of China. Published by Elsevier Taiwan LLC. All rights reserved., Department of Scientific Research Projects of Erciyes University, The authors thank Dr Aslihan Usumez and Dr Ahmet Ozturk for their valuable contributions in the assessment of study results and preparation and writing of this manuscript. The authors gratefully acknowledge financial support from the Department of Scientific Research Projects of Erciyes University.

Poor chemical bonding of acrylic resins to metal alloys can result in microleakage and failure of the bond. Metal primers have been shown to be effective in improving the bond strength of acrylic resins to metal alloys. However, there is insufficient information about their effects on bonding to different types of metals.The purpose of this study was to evaluate the effect of metal primers on the shear bond strength of acrylic resins to 3 different types of metals.A total of 432 disk-shaped wax patterns (10 mm in diameter and 2 mm thick) were cast in a Ti alloy (Tritan), base metal (Co-Cr alloy, Wironit), or noble metal (Au-Ag-Pt alloy, Mainbond EH). After casting, the disk surfaces were finished with abrasive paper under water. The noble alloy was airborne-particle abraded with 50-microm aluminum oxide; the other alloys were airborne-particle abraded with 110-mum aluminum oxide for 10 seconds. Specimens of each metal were divided into 3 groups (n=48) and received 1 of the following acrylic resins: (1) heat polymerized (Meliodent), (2) autopolymerized (Meliodent), or (3) microwave polymerized (Acron MC). The specimens were then divided into 4 subgroups (n=12) which received 1 of the following metal primers: (1) Metal Primer, (2) Alloy Primer, (3) Meta Fast, or (4) no primer (control). All specimens were stored in distilled water at 37 degrees C for 24 hours after polymerization and then thermal cycled (5000 cycles at 5-55 degrees C with a 30-second dwell time). After thermal cycling, the specimens were tested in a universal testing machine at a crosshead speed of 0.5 mm/min in shear mode. Data (MPa) were analyzed using 3-way ANOVA and the post hoc Tukey HSD test (alpha=.05).The 3-way ANOVA indicated that shear bond strength (SBS) values varied according to the metal type, metal primer, and acrylic resin used (P.001). The SBS between base metal and heat-polymerized resin with Metal Primer was the highest (3.6 +/-0.67 MPa), and the SBS between noble metal and acrylic resin, for all control groups, was the lowest (0.4 +/-0.07 MPa) (P.001). For titanium, the highest SBS was observed for Meta Fast and the lowest for the control group. For base metal, the highest SBS was recorded for Metal Primer and the lowest for the control group, while for noble metal, the highest SBS was observed for Alloy Primer and the lowest for the control group (P.001).The metal primers were associated with an increase in the adhesive bonding of acrylic resins to metal alloys. The SBS of the acrylic resin to the base metal alloy was significantly higher than the SBS to the noble and titanium alloys.

The effects of desensitizer, disinfectant, saliva, blood, and hydrogen peroxide on the tensile bond strength between adhesive and ceramic as well as between adhesive and dentin were examined. Sixty 7x3 mm pressed ceramic discs of IPS e.max were fabricated and randomly assigned to six groups of different dentin surface treatments (control, desensitizer, disinfectant, saliva, blood, and hydrogen peroxide). Representative samples of fractured specimens were observed by SEM (scanning electron microscopy). There were significant differences between the control group and saliva, blood, and hydrogen peroxide groups (p0.05). Results of this study suggested that only saliva, blood, and hydrogen peroxide influenced the tensile bond strength between dentin and ceramic.

Papillon-Lefevre syndrome (PLS) is an autosomal recessive disorder. Main features of PLS are hyperkeratosis of palms and soles concomitant with premature loss of primary and permanent dentition due to progressive periodontitis. Dental management of patients with PLS is usually challenging because of early excessive loss of alveolar bone support. We describe dental rehabilitation of a 34-year-old patient with PLS with severely atrophic mandible by means of 2 short (6 mm) dental implants between 2 mental foramina supporting an implant retained complete denture. After 1 year of follow-up period, the patient was doing well and there was no sign of bone resorption. In patients with PLS, dental osseointegrated implants (even with shorter lengths) can be safely used for atrophic mandibles instead of invasive preprosthetic applications such as bone augmentation, nerve lateralization, or alveolar distraction to avoid possible complications. (Implant Dent 2010;19:394-399)

Objectives: The aim of this study was to investigate surface roughness in provisional crown acrylics, after polishing, reinforced with different concentrations of glass fibers.Methods: A total of 48 disk-shaped specimens were prepared using autopolymerizing acrylic resin. These specimens were divided into four groups according to the level of glass fiber added: Group A (no fiber), Group B (0.5%), Group C (1%) and Group D (2%). After polishing the specimens, an average surface roughness (Ra) value was calculated using a profilometer from four randomly selected points on the surface.Results: A significant difference was determined among the surface roughness values of provisional crown resins to which different concentrations of fiber had been added (PConclusions: The reinforcement of provisional crown and fixed partial denture resin with glass fibers increases surface roughness. (Eur J Dent 2008;2:185-190)

The purposes of this study were to compare the gingival blood flow (GBF) in test sites (teeth retaining fixed partial dentures) and control sites (contralateral natural teeth) and investigate whether there is any relationship between clinical indices and GBF values. Twelve healthy subjects (6 females and 6 males) aged 20 to 54 years were enrolled this study. The GBF was measured from the middle point of the marginal gingiva in the test and control sites using laser Doppler flowmetry (LDF). Additionally, plaque index, gingival index and probing depth measurements were recorded. Statistically significant difference (p0.05) was found between test and control sites with respect to the clinical indices, except for plaque index. The findings of this study suggest that there is a significant relation between resin-bonded fixed partial dentures with margins located subgingivally and marginal GBF. Clinical indices are helpful to collect information about the clinical health status of gingival tissues, but GBF is a good tool to measure gingival tissue blood flow and assess periodontal health. In conclusion, laser Doppler flowmetry can be used together with clinical indices to evaluate the marginal gingival health. Os objetivos deste estudo foram comparar o fluxo sangüíneo gengival (FSG) em sítios teste (dentes retentores de próteses parciais fixas) e sítios controle (dentes naturais contralaterais) e investigar se há alguma relação entre os índices clínicos (IC) e os valores de FSG. Doze indivíduos saudáveis (6 mulheres e 6 homens) com idades entre 20 a 54 anos participaram deste estudo. O FSG foi medido no ponto médio da gengina marginal em ambos os sítios teste e controle utilizando dopplerfluxometria a laser (DFL). Além disso, as medidas referentes ao índice de placa, índice gengival e profundidade de sondagem foram registradas. Foi observada diferença estatisticamente significante (p0.05) entre os sítios teste e controle com relação aos índices clínicos, exceto para o índice de placa. Os achados deste estudo sugerem que existe uma relação significante entre próteses parciais fixas retidas por resina com margens localizadas subgengivalmente e o FSG marginal. Embora os índices clínicos sejam úteis para coletar informações sobre as condições clínicas dos tecidos gengivais, o FSG é uma ferramenta importante para medir o fluxo sanguíneo tissular gengival e avaliar a saúde periodontal. Em conclusão, a dopplerfluxometria a laser pode ser usada juntamente com índices clínicos para avaliar a saúde gengival marginal.

In this study, the functional stresses in alveolar bone created by restorative materials used in implant-supported prostheses were determined by the photoelastic stress analysis method. A photoelastic resin mandibular model, hollow-cylinder implants (3.5 mm diameter, 10 mm length), and fixtures and superstructures made of five different prosthetic materials were used. Vertical and 45-degree inclined loads were applied to the model. Subsequently, color photographs of the force line distribution observed on a polariscope were taken. Differences between vertical and inclined loads were statistically significant for all prosthetic materials (P < 0.01). The greatest stress distribution around the apex of the implant was observed with Ceramco II porcelain, followed by Biodent acrylic. The ArtGlass and Elcebond CCV composite materials had equal values, whereas Verebond Ni-Cr alloy showed minimum stress distribution.