Maksilla Posterior Bölgede Vertikal Kemik Miktarının Yetersizliği Durumunda Uygulanan Kısa İmplantların Üzerindeki Ve Etrafındaki Kuvvet Dağılımının Sonlu Elemanlar Analizi ile Değerlendirilmesi

Öz

Amaç: Bu çalışmanın amacı; 3 boyutlu sonlu elemanlar analiz yöntemi ile posterior maksiller dişsiz bölgeye uygulanan kısa dental implantların üzerinde ve çevresinde oluşan kuvvet dağılımlarının incelenmesidir.

Yöntem: Maksiller sinüs pnömatizasyonu bulunan dişsiz posterior alana sahip sağlıklı bir bireyin bilgisayarlı tomografi görüntüleri temel alınarak bir model oluşturuldu. Ardından 6,5 mm uzunluğunda ve 4 mm çapında vida tipi silindirik implant modeli oluşturuldu. Vertikal ve oblik kuvvetler simüle edilerek üç boyutlu sonlu elemanlar stres analizi yöntemi ile implant üzerinde ve çevre kemik üzerinde oluşan stresler değerlendirildi.

Bulgular: Vertikal ve oblik yükleme esnasında implant üzerinde oluşan streslerin değerlendirilimesi için von Mises stresi sonuçları hem sayısal olarak hem de renklendirilmiş görüntüler olarak kaydedilmiştir. Kortikal kemik ve kansellöz kemik üzerinde belirlenen 4 bölge üzerinde oluşan von Mises stres, çekme stresi ve baskı stresi sonuçları hem sayısal olarak hem de renklendirilmiş görüntüler olarak değerlendirilmiştir. Buna göre; streslerin kansellöz kemiğe oranla kortikal kemikte yoğun olduğu görülmüştür. Ayrıca, en yüksek kuvvetler implant içerisinde oluştuğu ve dayanak-implant birleşimi yakınında, implantın kortikal kemik ile komşuluk yaptığı bölge sınırında yoğunlaştığı görülmüştür.

Sonuç: Çalışılan tüm modellerde elde edilen stres değerlerinin yıkıcı sınırlara yaklaşmaması sebebiyle, maksiller posterior dişsiz bölgede kısa implantların kullanımının başarılı olabileceği öngörülmüştür. İmplantlara gelen oblik kuvvetlerin oluşturduğu stresin daha yüksek değerlerde olduğu düşünülerek, özellikle kısa implant yerleştirileceği zaman, implantların mümkün olduğunca okluzal kuvvetlere paralel şekilde yerleştirilmesi biyomekanik açıdan önemlidir.

Anahtar Kelimeler

• Sonlu Eleman Analizi,Kısa İmplant,Posterior Maksilla,Vertikal Kemik Yetersizliği

Evaluation of Stress Distribution with Finite Element Analysis on and around Short Implants in Case of Inadequate Vertical Bone Quantity in Maxilla Posterior Region

Öz

Purpose: The aim of this study was to evaluate the stress distribution on the short implant and surrounding bone that was applied to posterior maxillary edentulous region.

Methods: The model was defined according to a computed tomography images of a healthy patient’s posterior edentulous region with maxillary sinus pneumatization. Then, 6.5mm length and 4mm diameter cylindrical titanium implant was modeled. Vertical and oblique forces  were simulated and evaluated with three-dimensionally finite element analysis method.

Results: For evaluating the stresses on the implant during vertical and oblique loading, von Mises stress results were recorded both numerically and as colored images. Von Mises stress, compressive stress and tensile stress on the four regions determined on cortical bone and cancellous bone were evaluated with numerical and colored images. According to results; stresses were found to be high in the cortical bone compared to the cancellous bone. Also, the highest stress was found on the implant body, and the stress were high at near the abutment-implant junction, region of the implant adjacent to the cortical bone.

Conclusion:   It is predicted that the use of short implants in maxillary posterior region could be appropriate because the obtained stress values in all models were not high as the destructive limits. Taking into account that the stress on the implants generated by the oblique forces is higher, for especially short implant placement, it is important biomechanically that the implants should be placed as possible as parallel to the occlusal forces.

Anahtar Kelimeler

• Finite Element Analysis,Short Implant,Posterior Maxilla,Vertical Bone Deficiency

Kaynakça

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