Fracture strength of resin-bonded dental prostheses with a rigid versus nonrigid joint. An in vitro study.
This in vitro study investigated whether a resin-bonded dental prosthesis (RBDP) with a hyperstatic, rigid joint was preferable to an isostatic, nonrigid construction in terms of debonding and fracture strength. RBDPs replacing a missing molar with a rigid (design I) or a resilient model (design II) were compared to a commercially available system (Crownless Bridge Work) (design III, control). All groups were subjected to thermocycling (TC) and dynamic mechanical loading (ML) in a dual-axis chewing simulator (TC: 6,000 x 5 degrees C/55 degrees C; ML: 1,200,000 x 49 N x 1.4 Hz). None of the RBDPs of design III showed movement or fracture during the test period. Significant differences between designs I and III (P= .0049) and between designs II and III (P = .0007) were noted. Despite a tendency for lower fracture values of design I, no significant differences could be established between the test designs with a rigid or nonrigid construction. The commercially available dental prosthesis with a nonrigid joint was confirmed to resist a 5-year survival simulation.
Department of Prosthetic Dentistry, School of Dentistry, Oral Pathology, and Maxillofacial Surgery, Faculty of Medicine, Leuven, Belgium.
Katrien M L
KM
Cleuren
Katleen
K
Vandamme
Ignace
I
Naert
D016734:Dental Clasps; D019232:Dental Restoration Failure; D003799:Dental Stress Analysis; D003779:Denture Design; D003781:Denture Retention / Q000295:instrumentation; D016379:Denture, Partial, Fixed, Resin-Bonded; D018583:Pliability