Gökhan Durmuş

Effects of post core materials on stress distribution in the restoration of mandibular second premolars: a finite element analysis.

STATEMENT OF PROBLEM Previous studies have not resolved the question as to which post and core combination optimizes the stress distribution within the post restoration and tooth. PURPOSE The purpose of this study was to determine which post and core combination provides the most favorable stress distribution upon loading. MATERIAL AND METHODS Three-dimensional models of teeth were created with the Ansys program to simulate different materials used for post and cores (Ti, NiCr, AuPd, zirconia, zirconia post/composite resin core, glass fiber post/composite resin core, and carbon fiber post/composite resin core) and metal ceramic crowns (nickel chromium alloy [Group NiCr] and gold palladium alloy [Group AuPd]). A force of 400 N was applied to the occlusal surface, and von Mises equivalent stress values were calculated. RESULTS Carbon fiber post/composite resin core/metal ceramic crowns with NiCr alloy core had the highest stress values in the weakened root, tooth/post interface, and post. NiCr post/NiCr core/metal ceramic crowns with NiCr alloy core had the lowest stress values in the weakened root and post. The zirconia post and core had the lowest stress value in the tooth/post interface. CONCLUSIONS A post material with a high elastic modulus led to lower stress in the weakened root (approximately 6%) and tooth/post interface (approximately 12%) and to higher stress in the post (approximately 5 times). A composite resin core led to higher stress in the weakened root (approximately 11% to 17%) and lower deformation in the tooth/post interface (approximately 17.5%) and post materials (approximately 24%). Group AuPd resulted in lower stress in the root and high stress in the post (approximately 4.5% to 7%) and affected the amount of deformation in posts with a composite resin core.

The Proposal of Restoration of Historical Kastamonu Castle’s

Permanence of Kastamonu Castle in Turkey which has been the witness of history emerges as the most important value. Historical places and structures are important expressions of community’s culture and identity. The structure can be provided to serve from the past to the future. In this study; characteristical features of Historical Kastamonu Castle, used materials and reasons of structural deterioration are analyzed for restoration suggestion. Historical Kastamonu Castle is important for long-lasting regional culture properties.

A Study on Some Factors Affecting on CO 2 Curing of Expanded Perlite Based Thermal Insulation Panel

Energy, which is needed for every aspect of life, plays a key role for the development of the countries. Countries need to use energy efficiently to be advantageous in the global competition and ensure the sustainable development. Countries using the energy efficiently succeed economically and have leading the field in the competition. The purpose of this study is to put forward to the role and importance of energy efficiency for the sustainable development of the countries. In this study, energy efficiency has been examined conceptually considering the studies in the literature and the role and importance of energy efficiency has been emphasized for the sustainable development of the countries.

The Assessment of Energy of Residential Building of District Korkuteli/ANTALYA

Annual primary energy consumption for sustainable construction operation and maintenance costs is estimated to be approximately 30–40%. The issue of increasing energy efficiency in buildings has become increasingly important. In addition, residential buildings are being surveyed in terms of energy efficiency compared to other buildings (offices, factories, shopping malls, etc.,). In this study, in order to determine the energy performance of buildings, the values of energy performance of 480 dwellings with different typology and area constructed in different districts of Antalya/Korkuteli district were analyzed by Building Energy Performance Program (BEP-TR) program prepared by Ministry of Environment and Urban Planning. The BEP-TR program has been evaluated in terms of energy performance evaluation of heating, cooling, hot water, lighting and greenhouse gas emissions. Each letter code of the energy performance of housing has been investigated statistically average assessed. As a result, while the heating values varied from A to G from energy performance, only class C appeared in the greenhouse gas distribution. In addition, when the averages are examined, the energy class of all houses is “Class C”.