ضبط الحواف ومقاومة الكسر لاغلفة ال Ceramill Sintron المعدنية المصممة والمصنعة بالحاسوب مكسوة بثلاث انواع مختلفة من الخزف == Marginal Discrepancy And Fracture Resistance of CAD\CAM Ceramill Sintron Metal Copings With Different Porcelain Materials
Author name:
مصطفى نبيل عبد الغني
Supervisor name:
عمار عطا الله علي السعدي
General topic:
Dentistry
Specific topic:
Oral and Maxillofacial Surgery
Degree:
Master
University:
Mustansiriyah University
Language:
English
University location:
Baghdad
First pages:
20T399 - p.pdf
Abstract:
دقة الحواف والقوة، لاي ترميم معوض للاسنان هي صفة مهمة. ويمكن اعتبارعدم تطابق للحواف او قلة القوة سبب مهم يؤدي الى فشل التعويضات الاصطناعية للاسنان.لذلك تم اجراء هذا البحث لغرض تقييم اختلاف ظبط حافات ومقاومة الكسر لتيجان السيراميك المصنعة من اغلفة الC | Marginal fit and strength are important criteria for any restoration; poor marginal fit and low strength may be considered as a source of prosthesis failure. This study was performed to compare the marginal fit changes and facture resistance of metal ceramic crowns constructed from Ceramill Sintron metal coping veneered with three different porcelain veneering materials (Vita Master Koromikos VMK, Willi Geller Creation CC and GC initial MC). Also evaluating the influence of thermocycling on load at fracture value. The method included the use of master brass die which was milled to represent the prepared maxillary central incisor. Sixty metal copings were milled directly using Ceramill Sintron blank, then divided randomly into three groups. Each group consist of twenty metal copings, then veneered with porcelain : VITA for group A, Creation for group B and GC for group C. The marginal gap was measured before and after porcelain veneering for each group using travelling light microscope, then marginal fit changes was calculated. Fracture resistance test was done by Instron®, the master die was duplicated to sixty analogs then each analog was fixed into acrylic base. After that each crown was cemented onto the corresponding die analog using zinc phosphate cement. Ten samples of each group were subjected to compressive loading to fracture and other ten subjected to thermocycling followed by compressive loading to fracture.The result showed that GC group was highly significant different from other tested groups in marginal fit changes, whereas there was no significant different between VITA and Creation group. While there was significant difference among tested group at (P < 0.01) in fracture resistance, and the effect of thermocycling process did not significantly reduce the load at fracture for all groups.This study concluded that GC group present the least marginal fit changes, while the fracture resistance was highest for VITA group follow by Creation then GC. Thermocycling reduce load at fracture but not significantly.
