the anaıysis of stress distribution on class 1 restorations by fınite elements methods

Aim: The main objective of the restorative dentistry is to regain the appearance of the natural teeth by accurate diagnosis and proper treatment. This study is planned to compare the stress values of tooth and class I restorations of five different restorative materials under the bite force by finite element stress analysis. Material and Method: In this study, the models which made by Rhinoceros 4.0 were transferred in the STL format to the ANSYS software based on the finite element method.Restorative materials used are: Group 1: Fiber-reinforced composites resin (Vectris Pontic, Ivoclar), Group 2: Amalgam (Dispersalloy, Johnson and Johnson, USA), Group 3: Filtek Z100 composite resin (Z 100.3 M ESPE Dental Product, USA), Group 4: Charisma composite resin (Heraeus Kulzer, Hanau, Germany) and Group 5: Herculite Composite Resin (Kerr Corp.. Orange, Calif.). All materials were loaded into the standard and angled Class I cavity models. The model is composed of restoration, the hard tissue of the tooth and enamel and dentin. Using this model, the numerical experiments were performed for five different restorative materials under the force of 250 N with the angle of 90 ° and 45°. No statistical analysis was applied to the values of the finite element analysis results because of the mathematical calculations that occur without any variances. The aim is to analyse the values and stress results carefully. Results: The maximum and minimum stresses were calculated seperately for all groups. Especially while analysing the maximum values in the restorations, different results were obtained. When all groups were evaluated, the maximum forces were occured in the enamel, the minimal forces were concentrated in the dentin. In general, the stresses created by the 45° angled forces were found to be up to 3 times to the stresses created by the 90° angled forces. Fiber composite restorations group is the most successful group compared with the other groups. The most unsuccessful group is the Herculite group. Conclusion: We found that the most ideal material used in this study is the Fiber reinforced resin composites. Cavities prepared angled on base showed less stress results compared with the standart cavities prepared on base. And the cavities prepared angled on base spread the stresses better. The Herculite composite material accumulated and conducted stresses mostly. Key Words: Finite element analysis method, restorative material, Stress Distribution, Class I cavity, Elasticity modüle.