A Retrospective Clinical Evaluation of Resin-bonded Bridges Inserted at the Adelaide Dental Hospital

The clinical performance of resin-bonded Rochette and Maryland bridges inserted by various operators at the Adelaide Dental Hospital is reported. Thirty-four Rochette bridges (30 anterior, 4 posterior) and 228 Maryland bridges (150 anterior, 78 posterior) were assessed. Clinical data were compiled on types of bridge failure, factors influencing bridge retention, and the effects of the prostheses on abutment teeth and supporting tissues. The failure rate for Rochette bridges over 6 years was 75 per cent with a median survival of 2.14 years. Debonding occurred in 70 per cent of bridge failures. The failure rate for Maryland bridges over 5 years was 42 per cent with a median survival of 2.60 years. Pontic fracture (29 per cent) and debonding (20 per cent) were the main failures observed. Porcelain pontics performed significantly better than the processed hybrid resin pontics (P < 0.01). The main reasons for debonding included occlusal stresses, non-retentive bridge designs and resin cement failure. A life-table analysis showed no significant difference in the overall cumulative survival rates between Rochette and Maryland bridges. Bridge design and the choice of pontic material and resin cement emerged as significant factors influencing the success rate of the bridges examined.