Mechanical interactions of an implant/tooth-supported system under different periodontal supports and number of splinted teeth with rigid and non-rigid connections

Objectives: This study investigated the mechanical interactions of implant-teeth splinting systems under different periodontal supports and number of splinted teeth with rigid and non-rigid connectors using non-linear finite element (FE) approach. Methods: Two FE models with normal and compromised periodontal supports containing a Frialit-2 implant splinted to the first and second premolars were constructed. Non-linear contact elements were used to simulate a realistic interface fixation within the implant system and the sliding function of the non-rigid connector. ANOVA was used to test for relative importance of the investigated factors and main effects for each level of the three investigated factors (periodontal supports, teeth splinting and connector designs) in terms of the stress values were performed. Results: The simulated results indicated that the cross-interaction of the periodontal support and the splinting situation was a major factor affecting the stress value in alveolar bone. An additional splinting decreased the stress values of bone significantly for a compromised periodontal support. The individual factor of periodontal support also influenced the stress found in the alveolar bone (28%) and implant (72%), and the stress values increased when the periodontal support was reduced. Using different connectors affected the stresses found in bone (15%), implant (21%) and prosthesis (99%). The stress values of the implant and prosthesis increased, but were decreased in bone when the splinting system used non-rigid connectors. The mobility of natural teeth and the implant system between non-rigid and rigid connections showed only small differences. Conclusions: A non-rigid connector should be used with caution since it breaks the stress transfer and increases the unfavorable stress values in the implant system and prosthesis. The tooth/implant-supported system with an additional splinting is more efficient in compromised periodontal supports.