ABSTRACT
The aim of this study is to evaluate the effectiveness of the implant diameter and length on force dissemination of tooth-implant and implant retained fixed restorations. A finite analysis model was used via a 3D simulation of a unilateral mandibular Kennedy Class I arch. Through thresholding the resultant assembly, a region of interest was selected from the computed tomography (CT) scan. Details of the diameter (D) and length (L) of implant were introduced. Ds used were 3.7, 4.7, and 5.7, while Ls used were 10, 11.5, and 13. The constant was the use of rigid connectors in both designs (implant-implant and implant-tooth fixed partial dentures [FPDs]) and the mesial implant (D 3.7 and L 11.5). Stress in cancellous bone around mesial abutment, which is the second premolar in tooth-implant FPD and mesial implant in the implant-implant FPD, revealed that the stress was significantly lower in tooth-implant FPD when compared with implant-implant FPD (21.1 ± 0.00 vs 46.1 ± 0.00, P < .001). Stress distribution in the bone around any implant depends on several factors such as diameter, length, and tooth-implant vs implant-implant support. The implant diameter was more significant for improved stress distribution than implant length. A moderate increase in the length of the implant consequently reduced stress.
