[Evaluation of fixed splinting in periodontally compromised abutments; utilizing 3-D finite element method [FEA]]

ABSTRACT

Fixed splinting of abutment teeth can alter the stress distribution characteristics of removable partial denture [RPD]. However, periodontally compromised abutments may complicate free end RPD treatment plans. The purpose of this study was to determine the effects of fixed splinting of periodontally compromised abutments on load distribution in free end RPD. Three-dimensional finite element models were designed for mandibular first and second premolars including their PDL and surrounding bony structures. In the first model the teeth had no periodontal involvement; in the second model, the first premolar was healthy, the second premolar had periodontal involvement [C/R=1]; and, in the third model both teeth had periodontal involvement [C/R=1]. Likewise, before and after fixed splinting, situations were defined for each model. The Von misses stress in surrounding bone was analyzed after applying 50 N loads on the specimens. In all three models the maximum Von misses stress before splinting were found to be in the apical area of teeth and the minimum was detected near the mesial crest of first premolar and distal crest of second premolar. After splinting the teeth together, a stress reduction was observed in the interdental crest areas; while in model 1 and 2, increase in the stress was observed in apical areas. The greatest remedy was demonstrated in model 2 where a periodontally compromised tooth was splinted to a healthy one. Fixed splinting of periodontally compromised teeth can reduce the stress concentration in the interdental crest areas and it can improve the stress distribution in the surrounding bone