A survey of chrome-cobalt RPD design in Ireland

Purpose: The aims of this study were to investigate the quality of written instructions given to dental laboratories for fabrication of chrome-cobalt removable partial dentures (RPD) in Ireland, and to examine the extent and nature of technical/laboratory support available for the fabrication of this prosthesis type. Materials and Methods: All dental laboratories listed in the commercial telephone book were contacted and invited to participate in the study. Written instructions received by dental technicians for fabrication of chrome-cobalt RPDs were examined for evidence of four design variables: denture base configuration, retention, support, and connector design. The use of diagrams was also examined. Results: Of 112 dental laboratories listed, 100 agreed to take part. Sixteen laboratories had the facilities to fabricate chrome-cobalt frameworks on their premises; 122 sets of written instructions were received. All four design variables were described in 10% (n = 12) of instructions, 7% (n = 9) contained reference to three variables, 13% (n = 16) contained reference to two variables, and 17% (n = 20) contained reference to one variable. No design features were prescribed in 53% (n = 65), and 5% (n = 6) requested the technician to design the prosthesis. Only 7% (n = 8) of instructions included a diagram. Conclusion: A high proportion of written instructions to dental laboratories regarding fabrication of chrome-cobalt RPDs contained no reference to the mentioned design variables.