Evaluation of seat and non-seat post preparation design using conventional and computational methods

• Main Authors: G. Subrata, Z. Hasratiningsih, E. Kurnikasari, T. Dirgantara
• Format: Article
• Language: English
• Published: Universitas Airlangga 2009-12-01
• Series: Dental Journal: Majalah Kedokteran Gigi
• Subjects: post preparation design; stress distribution; finite element method (FEM); root fracture resistance
• Online Access: http://e-journal.unair.ac.id/index.php/MKG/article/view/939
• ISSN: 1978-3728; 2442-9740

<span style="font-family: Tribune-Bold; font-size: 10pt; color: #231f20; font-style: normal; font-variant: normal;"><strong>Background: </strong><span style="font-family: Tribune-Italic; font-size: 9pt; color: #231f20; font-style: normal; font-variant: normal;"><em>Design of root canal preparation especially in cervical-third area of the root, is one of many factors involved in the </em><span style="font-family: Tribune-Italic; font-size: 9pt; color: #231f20; font-style: normal; font-variant: normal;"><em>success of post-core restoration. Seat design that is used in Prosthodontics Installation, Faculty of Dentistry, University of Padjadjaran, </em><span style="font-family: Tribune-Italic; font-size: 9pt; color: #231f20; font-style: normal; font-variant: normal;"><em>is in the contrary to minimal preparation design. The root fracture resistance of this design has not been proven yet. </em><span style="font-family: Tribune-Bold; font-size: 10pt; color: #231f20; font-style: normal; font-variant: normal;"><strong>Purpose:</strong><span style="font-family: Tribune-Italic; font-size: 9pt; color: #231f20; font-style: normal; font-variant: normal;"><em> The </em><span style="font-family: Tribune-Italic; font-size: 9pt; color: #231f20; font-style: normal; font-variant: normal;"><em>aim of this study was to evaluate the root fracture resistance of seat compare to non-seat design, with two different research methods: </em><span style="font-family: Tribune-Italic; font-size: 9pt; color: #231f20; font-style: normal; font-variant: normal;"><em>experimental laboratory and computer simulation with Finite Element Method (FEM). </em><span style="font-family: Tribune-Bold; font-size: 10pt; color: #231f20; font-style: normal; font-variant: normal;"><strong>Method: </strong><span style="font-family: Tribune-Italic; font-size: 9pt; color: #231f20; font-style: normal; font-variant: normal;"><em>The experimental laboratory investigation </em><span style="font-family: Tribune-Italic; font-size: 9pt; color: #231f20; font-style: normal; font-variant: normal;"><em>used 20 upper central incisors: 10 used seat design and 10 non-seats, with the cast posts cemented in the preparation. The specimens </em><span style="font-family: Tribune-Italic; font-size: 9pt; color: #231f20; font-style: normal; font-variant: normal;"><em>were tested by using Universal Testing Machine with compressive force until the root fracture. The FEM used 2D digital models: seat </em><span style="font-family: Tribune-Italic; font-size: 9pt; color: #231f20; font-style: normal; font-variant: normal;"><em>and non-seat design of maxillary central incisors using a finite element software. The distribution of internal stress caused by static </em><span style="font-family: Tribune-Italic; font-size: 9pt; color: #231f20; font-style: normal; font-variant: normal;"><em>loading 110N at 135</em><span style="font-family: Tribune-Regular; font-size: 9pt; color: #231f20; font-style: normal; font-variant: normal;">° <span style="font-family: Tribune-Italic; font-size: 9pt; color: #231f20; font-style: normal; font-variant: normal;"><em>angle with longitudinal axis of the tooth was evaluated. </em><span style="font-family: Tribune-Bold; font-size: 10pt; color: #231f20; font-style: normal; font-variant: normal;"><strong>Result: </strong><span style="font-family: Tribune-Italic; font-size: 9pt; color: #231f20; font-style: normal; font-variant: normal;"><em>The results of the fracture strength test showed </em><span style="font-family: Tribune-Italic; font-size: 9pt; color: #231f20; font-style: normal; font-variant: normal;"><em>a significant difference (p = 0.05) between the non-seat group (852.27N ± 112.6N) and the seat group (495.78N ± 82.90N). The FEM </em><span style="font-family: Tribune-Italic; font-size: 9pt; color: #231f20; font-style: normal; font-variant: normal;"><em>showed a lower stress concentration in non-seat compare to seat group. This study proved that non-seat distributes stress better than </em><span style="font-family: Tribune-Italic; font-size: 9pt; color: #231f20; font-style: normal; font-variant: normal;"><em>seat design. </em><span style="font-family: Tribune-Bold; font-size: 10pt; color: #231f20; font-style: normal; font-variant: normal;"><strong>Conclusion: </strong><span style="font-family: Tribune-Italic; font-size: 9pt; color: #231f20; font-style: normal; font-variant: normal;"><em>It can be concluded that the FEM confirmed the result of the laboratory method. Stress concentration will </em><span style="font-family: Tribune-Italic; font-size: 9pt; color: #231f20; font-style: normal; font-variant: normal;"><em>cause fracture, therefore root fracture resistance in the non-seat design was higher than the seat design.</em></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span></span>