Özet:

Purpose: Excessive resorption of the mandibula is a full dysfunction; implant applications, the provision of oxytocin and the use of active prothesis are commonly observed problems. Mandibular 4 is an alternative method for fixed full arc prothetic restorations made on the implants. The low number of implants, the short duration of the surgical procedures and the fixed prothesis are the features of this method. The aim of this study is to evaluate the application of monolithic zirconium CAD-CAM ceramic materials in different mandibuler all on four implant designs in terms of the biomechanical characteristics. Materials and methods: Katana CAD-CAM monolithic zirconium is used in full ark fixed restoration, Biomed implant and abutment materials. 4 mandibuler all on four implant designs are prepared. 1. model; anterior implants vertical and posterior implants 150 angles, cantilever 5 mm, (Z-15,5); 2. model; cantilever 9 mm (Z-15,9); 3. model anterior implants vertical posterior implants 300 angles, cantilever 5 mm (Z-30,5); 4. model; cantilever 9 mm (Z-30,9). Charge condition; 1. molar charge was applied from the center of the right kantilever extension to the oxygen plate with a angle of 30o and a strength of 150 N. Three-dimensional final elements were measured by the stress analysis method of the mandibular cortical and spongiotic bone, implant and prothetic restorations of the biomechanical stress distribution. Statistical linear analysis. The findings: When all the parameters were evaluated together, it was found that there were significant links between the CAD-CAM ceramic material, the length of the kantilever and the types of stress distribution. When the length of the cantilever increased from 5 mm to 9 mm, the maximum and minimum original voltage stress values in the cortical and trabecular bones increased from 15 to 32 MPa. When the postterior implant opening increased from 150 to 300, the von Mises values in the implants decreased. Result: Monolithic zirconium restoration 30o posterior implant opening and 5 mm kantilever extension can be used as biomechanical. Mandibuler all on four implants supported full-layer stable aesthetic CAD-CAM restorations can be recommended by the biomechanical and clinical extraction of the cantilever to increase the angle of the implant and to perform single layer restorations. Keywords: monolithic zirconia, three-dimensional end elements stress analysis, all on four implant design Biomechanical behaviors of full countor zirconia restorations on different all on four mandibular implant models: A 3 dimensional finite element stress analysis study ABSTRACT Aim: Extremely resorbed mandibular total edentulism is most commonly seen with implant applications, occlusion and moving prosthetic use. The fixed whole arch prosthetic restorations on the mandibular 4 implants provide an alternative method. The low number of implants, short duration of surgical procedures, and fixed prosthesis are the characteristics of this method. The aim of this study is to evaluate the application of aesthetic& state of the art technology product of monolithic zirconia CAD-CAM ceramic materials in different mandibular "all four implants" designs in terms of biomechanical properties. Material&Method: Catana CAD-CAM monolithic zirconia full-arc fixed restoration, Biomed implant and abutment materials were used. 4 models of mandibular "all-on-four implants" were prepared. 1. model; anterior implants vertical and 150 angled posterior implants, cantilever 5 mm, (Z-15,5); 2. model; cantilever 9 mm (Z-15,9), 3. model; anterior implants vertical 300 angled posterior implants, cantilever 5 mm (Z-30,5); 4. The cantilever is 9 mm (Z-30,9). Loading condition; The 1st molar loading was applied from the center of the right cantilever extension to the occlusion plane with an angle of 30 degrees and a force of 150 N. Biomechanical stress distribution of mandibular cortical and spongious bone, implant and prosthetic restorations were measured by three-dimensional finite element stress analysis method. Static linear analysis was performed. Results: When all parameters were evaluated together, it was found that there were significant connections between the types of CAD-CAM ceramic material, the length of the cantilever and the types of stress distribution. When cantilever length was increased from 5 mm to 9 mm, maximum and minimum main stress values in cortical and trabecular bone were increased from 15 to 32 MPa. When Posterior implant angles increased from 15 to 30 degrees, the von Mises values of the implants decreased. Conclusion: Monolithic zirconia restoration can be used biomechanically with 30 degrees posterior implant angle and 5 mm cantilever extension. Biomechanically shortening cantilever, increasing implant angle and rigid monolithic restorations can be suggested on Mandibular "all-on-four implant" supported full-arc fixed aesthetic CAD-CAM restorations Key words: monolithic zirconia, three dimensional finite element stress analysis, all on four implant design

Anahtar Kelimeler:

Özet:

Amaç: Aşırı rezorbe mandibular tam dişsizlik; implant uygulamaları, oklüzyonun sağlanması ve hareketli protez kullanımı yaygın gözlenen problemlerdir. Mandibular 4 implant üzerine yapılan sabit tam ark protetik restorasyonlar alternatif bir metod sağlamaktadır. İmplant sayısının az olması, cerrahi işlemlerin kısa sürmesi ve sabit protez yapılması bu yöntemin özellikleridir. Bu çalışmanın amacı estetik ve son teknoloji ürünü olan monolitik zirkonya CAD-CAM seramik materyallerin farklı mandibuler all on four implant tasarımlarında uygulanmasının biyomekanik özellikler bakımından değerlendirilmesidir. Materyal ve metod: Katana CAD-CAM monolitik zirkonya tam ark sabit restorasyon, Biomed implant ve abutment materyalleri kullanıldı. 4 adet mandibuler all on four implant tasarımlı model hazırlandı. 1. model; anterior implantlar vertikal ve posterior implantlar 150 açılı, kantilever 5 mm, (Z-15,5); 2. model; kantilever 9 mm (Z-15,9); 3. model anterior implantlar vertikal posterior implantlar 300 açılı, kantilever 5 mm (Z-30,5); 4.model; kantilever 9 mm (Z-30,9). Yükleme koşulu; 1. molar yüklemesi sağ kantilever uzantısının merkezinden oklüzyon düzlemine 30o açılı ve 150 N kuvvet uygulandı. Üç boyutlu sonlu elemanlar stres analiz yöntemi ile mandibular kortikal ve spongioz kemik, implant ve protetik restorasyonlardaki biyomekanik stres dağılımı ölçüldü. Statik lineer analiz yapıldı. Bulgular: Bütün parametreler birlikte değerlendirildiği zaman CAD-CAM seramik materyal, kantilever uzunluğu ve stres dağılımının tipleri arasında önemli bağlantılar olduğu tespit edildi. Kantilever uzunluğu 5 mm’ den 9 mm’ ye çıktığı zaman kortikal ve trabeküler kemikte maksimum ve minimum asal gerilme stres değerleri 15’ den 32 MPa değerine yükseldi. Posterior implant açılanması 150’ den 300 ‘ye çıktığı zaman implantlarda von Mises değerleri azaldı. Sonuç: Monolitik zirkonya restorasyon 30o posterior implant açılanması ve 5 mm kantilever uzantısı biyomekanik olarak kullanılabilir. Mandibuler all on four implant destekli tam ark sabit estetik CAD-CAM restorasyonlarda biyomekanik ve klinik açıdan kantileverin kısaltılması implant açısının arttırılması ve rijit tek tabaka restorasyonların yapılması önerilebilir. Anahtar kelimeler: monolitik zirkonya, üç boyutlu sonlu elemanlar stres analizi, all on four implant tasarımı    Biomechanical behaviors of full countor zirconia restorations on different all on four mandibular implant models: A 3 dimensional finite element stress analysis study   ABSTRACT Aim: Extremely resorbed mandibular total edentulism is most commonly seen with implant applications, occlusion and moving prosthetic use. The fixed whole arch prosthetic restorations on the mandibular 4 implant provide an alternative method. The low number of implants, short duration of surgical procedures, and fixed prosthesis are the characteristics of this method. The aim of this study is to evaluate the application of aesthetic& state of the art technology product of monolithic zirconia CAD-CAM ceramic materials in different mandibular "all four implant" designs in terms of biomechanical properties. Material&Method: Katana CAD-CAM monolithic zirconia full-arc fixed restoration, Biomed implant and abutment materials were used. 4 models of mandibular "all-on-four implants" were prepared. 1. model; anterior implants vertical and 150 angled posterior implants,  cantilever 5 mm, (Z-15,5); 2. model; cantilever 9 mm (Z-15,9), 3. model; anterior implants vertical 300 angled posterior implants, cantilever 5 mm (Z-30,5); 4. model; cantilever 9 mm (Z-30,9). Loading condition; The 1st molar loading was applied from the center of the right cantilever extension to the occlusion plane with an angle of 30 degrees and a force of 150 N. Biomechanical stress distribution of mandibular cortical and spongious bone, implant and prosthetic restorations were measured by three dimensional finite element stress analysis method. Static linear analysis was performed. Results: When all parameters were evaluated together, it was found that there were significant connections between the types of CAD-CAM ceramic material, the length of the cantilever and the types of stress distribution. When cantilever length was increased from 5 mm to 9 mm, maximum and minimum principal stress values in cortical and trabecular bone were increased from 15 to 32 MPa. When Posterior implant angles increased from 15 to 30 degrees, the von Mises values of the implants decreased. Conclusion: Monolithic zirconia restoration can be used biomechanically with 30 degree posterior implant angle and 5 mm cantilever extension. Biomechanically shortening cantilever, increasing implant angle and  rigid monolithic restorations can be suggested on Mandibular "all-on-four implant" supported full-arc fixed aesthetic CAD-CAM restorations Key words: monolithic zirconia, three dimensional finite element stress analysis, all on four implant design