Fabrication of Removable Partial Denture Framework by Selective Laser Melting

The removable partial denture framework is very complex in shape with many curved surfaces, which is a very important assistant tool in prosthodontics. Generally, frameworks are fabricated by single piece basing on mould by traditional cast technology, which has many shortages of multiple steps, time cost and defects such as sand adheres, inner holes, cracks and segregation etc. As a novel method, selective laser melting (SLM) rapid prototyping technology has the advantages of short manufacturing cycle, high precision and flexibility, simple fabrication arts, which can be used to replace the conventional cast technology in the areas of prosthodontics. A SLM system was designed and developed by ourselves, which is consisted of an Yb-fiber laser, an optical scanner, a powder coating device, a gas purification system and a control system, the process parameters were investigated systematically and optimized, finally fabricated removable partial denture frameworks with stainless steel and titanium materials successfully by using the SLM system under optimized parameters. The tests showed that the frameworks have an average dimension precision of ±0.172mm. The wearing experiments on the plaster mouth molds demonstrated the removable partial denture frameworks fabricated by SLM can be fully applied to clinic after some post- processing procedures.