Evaluation of Stress Distribution of Mini Dental Implant-Supported Overdentures in Complete Cleft Palate Models: A Three-Dimensional Finite Element Analysis Study.

OBJECTIVE: Mini dental implants could be an alternative treatment method for prosthetic treatment of edentulous cleft palate. The aim of this study was to analyze stress distribution around the cortical bone and different plans using a varied number of mini dental implants in edentulous unilateral complete cleft palates. MATERIALS AND METHODS: Three edentulous maxillary models were modified to create unilateral complete cleft palates. Mini dental implants (2.4 x 15 mm) were located as two mini implants at the premolar region, four mini implants at the premolar and molar region, and six mini implants at the first premolar, second premolar, and first molar regions in the models, respectively. Mucosa, o-ring/ball attachments, and overdentures were simulated. Vertical and horizontal loads of 100 N were applied on both the right and left molar teeth of the overdenture for each model. Maximum and minimum principal stress values and the distribution at cortical bone around the implants and cleft palates were evaluated by finite element analysis. RESULTS: Stress values under vertical loads were lower than values under horizontal loadings for all models. Stress values were found to be lower in the first model than in the second and third models. The highest stress values were found around implants in the second model. The unilateral feature of a complete cleft pattern affected the stress distribution. CONCLUSION: Stresses occured mostly around implants when the overdenture was supported by six implants; however, the stress distribution around implants was low with two implants because of tissue support.