Effect of reinforcement methods on the retention of resin-bonded fixed partial dentures using a composite denture tooth as a pontic: in vitro evaluation.
OBJECTIVE
The incorporation of composite denture teeth as pontics in resin-bonded fixed partial dentures has been deemed to be short-lived. This study investigated whether pre- or posttreatments could improve the bonding of denture tooth pontics.


METHODS
A model fixed partial denture was fabricated that included composite denture teeth (Endura) bonded with 1 of 2 resin systems (C&B-Metabond or Aeliteflo). The bonding surface of the pontic was pretreated with one of three methods (air-particle abrasion [AA], AA plus silanization, or cavity preparation plus AA). The bonding areas between pontic and abutments were posttreated with 1 of 2 methods (reinforcement with fiber or metal post). Five bonded specimens for each treatment group were subjected to 20,000 thermocycles (40 degrees C to 60 degrees C; dwell time 60 s) before retentive forces (N) were determined. All data were analyzed with two-way ANOVA and Bonferroni's test (p = 0.05).


RESULTS
All specimens that underwent the pre- and posttreatment outperformed untreated specimens. For the specimens bonded with C&B-Metabond and posttreated with a polyethylene fiber (Ribbond) or a metal post (DC Post), the mean retentive forces were 316 N and 301 N for mandibular specimens, and 354 N and 380 N for maxillary specimens, respectively. These values were significantly higher than those obtained with other pretreatment methods (p < or = 0.0003). For mandibular specimens bonded with Aeliteflo, specimens posttreated with Ribbond exhibited significantly higher retentive forces (332 N) compared to other specimens (p < or = 0.0001).


CONCLUSIONS
Within the limitations of this study, the bond strength of a resin-bonded fixed partial denture incorporating a composite denture tooth as the pontic was improved by reinforcement with either a polyethylene fiber or a metal post.
Minesaki
Yoshito
Y
Department of Fixed Prosthodontics, Kagoshima University Dental School, Japan. yminesaki@aol.com
Suzuki
Shiro
S
Kajihara
Hirotada
H
Tanaka
Takuo
T
D000704:Analysis of Variance; D017609:Barium Compounds / Q000737:chemistry; D017438:Bisphenol A-Glycidyl Methacrylate / Q000737:chemistry; D001896:Boron Compounds / Q000737:chemistry; D003188:Composite Resins / Q000737:chemistry*; D000044:Dental Abutments; D001840:Dental Bonding / Q000379:methods*; D045662:Dental Etching; D003764:Dental Materials / Q000737:chemistry; D003781:Denture Retention; D016379:Denture, Partial, Fixed, Resin-Bonded; D006801:Humans; D008689:Methacrylates / Q000737:chemistry; D008768:Methylmethacrylates / Q000737:chemistry; D011095:Polyethylenes / Q000737:chemistry; D011176:Post and Core Technique; D019279:Resin Cements / Q000737:chemistry; D012821:Silanes / Q000737:chemistry; D012822:Silicon Dioxide / Q000737:chemistry; D013816:Thermodynamics; D019231:Tooth Preparation, Prosthodontic; D014093:Tooth, Artificial
C121035:Aeliteflo; D017609:Barium Compounds; D001896:Boron Compounds; D003188:Composite Resins; D003764:Dental Materials; D008689:Methacrylates; D008768:Methylmethacrylates; D011095:Polyethylenes; C084063:RIBBOND; D019279:Resin Cements; D012821:Silanes; D017438:Bisphenol A-Glycidyl Methacrylate; D012822:Silicon Dioxide; C049495:Super-bond