Objectives: This five-year clinical trial compared clinical performance and retention in two groups of resin-bonded, fixed-partial dentures (RBFPD). The treatment group, TG, received an all-porcelain (AP) RBFPD. The control group, CG, received a metal framework (MF) RBFPD. Retention was compared at the 5% significance level. Also, clinical performance was evaluated using modified Ryge criteria.
Methods: A pre-existing group of 11AP RBFPDs was identified in a private practice. A group of 5 MF RBFPDs was created. Matching was on age and prosthesis location, mandibular or maxillary. MF RBFPDs included tooth preparation; AP RBFPDs did not. AP RBFPDs were milled from solid porcelain (Vitablocs Mark II). At the baseline examination, the AP RBFPDs were one to two years old. The CG restorations were new. Partial or total loss of bond was considered failure. Ryge criteria were modified by adding Alpha 2 (A2) and Bravo 2 (B2) ratings. In the first year following the baseline exam, three of the five CG restorations but none of the 11 TG restorations debonded. The difference was significant (Fischer's Exact Test; p = 0.018).
Results: Baseline ratings for the abutment teeth were as follows: For Color Alfa ratings for TG and CG respectively were 100% and 90%. For Anatomic Form, Alfa ratings were TG 18% and CG 10%. B2 ratings were TG 73% and CG 60%. Five-year ratings: For Color Alfa ratings for TG and CG respectively were 100% and 100%. For Anatomic Form, Alfa ratings were TG 30% and CG 0%. B2 ratings were 30% for TG and CG 0%. The all-porcelain resin-bonded fixed-partial dentures exhibited superior retention compared to the resin-bonded, fixed-partial dentures.
Conclusions: The all-porcelain resin-bonded fixed-partial dentures fabricated by a novel application exhibited superior retention when compared to the metal framework resin-bonded, fixed-partial dentures in five years.