Fiber-reinforced composite inlay fixed partial dentures: the influence of restorative materials and abutment design on stress distribution investigated by finite element model.
OBJECTIVE
Fiber-reinforced composite may be successful used to fabricate inlay fixed partial dentures. This study used a finite element model to investigate three-dimensional stress distribution in a 3-unit fiber-reinforced composite fixed partial denture, and compared three types of fiber and three abutment configurations.


METHODS
A finite element model of a 3-unit fixed partial denture was used to investigate stress distribution in three different fiber-reinforced composite systems (1) Ribbond Triaxial plus Sinfony; 2) EverStick plus Sinfony; 3) Vectris Pontic/Frame plus Sinfony) and in three different abutment configurations (minimal distal-occlusal and mesial-occlusal preparation; extensive distal-occlusal and mesial-occlusal preparation; mesial-occlusal-distal preparation of both abutment teeth). Maximum load of 196 N was applied at the center of the occlusal and buccal surfaces of the pontic. Stress distribution was calculated in the tooth/restoration complex and in the abutment preparation.


RESULTS
When a vertical load was applied, no substantial differences between stress amount in the molar and in the premolar connectors was found. When a lateral load was applied, the stress was greater in the premolar connector than in the molar connector. In all designs investigated, stress was concentrated at the cervical margins of the proximal boxes adjacent to the pontic; no stress concentrated at the occlusal box preparation surface.


CONCLUSIONS
Within the limitations of this study, the results suggest that different fiber-reinforced composite systems show similar pattern of stress distribution. Stress concentrates at the connector areas and in the prepared teeth. Peak stress is at the cervical margin of the boxes adjacent to the pontic.
Rappelli
G
G
Department of Prosthodontics School of Dentistry, University Polytechnic of Marche, Ancona, Italy. g.rappelli@univpm.it
Scalise
L
L
Coccia
E
E
Procaccini
M
M
D000044:Dental Abutments; D003764:Dental Materials; D003794:Dental Restoration, Temporary; D003830:Denture, Partial, Fixed; D020342:Finite Element Analysis; D006801:Humans; D007284:Inlays; D008422:Materials Testing; D013314:Stress, Mechanical
D003764:Dental Materials