Martin Bullemer, Business Development Manager Medical at EOS explains: "Compared to the conventional approaches that have been used up to now to produce removable partial dentures, clear competitive advantages can be achieved using AM.
"Digitally manufactured partial dentures have been tested with pilot customers. The feedback has been very positive, encouraging us to continue to develop and optimise the application."
Michaela Flussfisch, Managing Director of dental laboratory Flussfisch GmbH in Hamburg, says: "During the pilot phase, we produced partial dentures based on Direct Metal Laser Sintering (DMLS) technology from EOS. Digitally manufactured dental prostheses have consistent tolerances and quality as well as reproducible properties and at the same time are very accurate, allowing a good fit."
If patients are missing several teeth, a removable dental prosthesis is an economical solution. However, the manufacture of such prostheses by conventional means is laborious and time-consuming for a dental laboratory: the preparation of the cast model, wax modelling based on it and finally the complete casting procedure including finishing.
If, on the other hand, a prosthesis is produced digitally using an AM system from EOS, a great deal of time can be saved. The prosthesis can be designed quickly with just a few mouse clicks using the flexibility of design offered by the modelling software. This leads to high strength, rigid and at the same time filigree geometries, while casting errors are eliminated.
The EOS metal system EOSINT M 270 Dental, which is established on the market, is used for manufacturing of removable partial dentures. The CE-certified material EOS CobaltChrome RPD, whose properties have been ideally matched to this dental application, is used as a basis for manufacturing. Density, elasticity, and elongation at break correspond to dental technology requirements.
During the additive manufacturing process, the fine powder particles ensure a fine-grain structure so that a digitally produced dental prosthesis has much higher strength and fatigue resistance than a casting. Additionally, the risk of a clamp breakage is reduced compared to a conventional cast model. The high level of detail supports the reproduction of grained structures. All manufacturing parameters are documented during the build process and the generation of parts is monitored. The material and system satisfy the high quality standards that apply for medical products and the finished products comply with the relevant standards EN 1641 and EN ISO 22674.
Additive manufacturing now an accepted process in the dental industry - nearly 100 systems installed
Applications exhibited on the EOS stand in addition to removable partial dentures include dental crowns, bridges and dental models. Integrated dental solutions from EOS allow the manufacture of reproducible, high-quality dental end-products at attractive unit costs. This is supported by integral EOS quality management to ensure product, process and service quality. For example, the material EOS CobaltChrome SP2 for manufacturing dental crowns and bridges is classified as a Class IIa medical material for dental applications (Directive 93/42/EEC). Materials and processes for the dental industry are developed in the ISO-certified EOS research and development centre. On request, the company provides customers with extensive consulting and support during the validation process.
Additive manufacturing of dental crowns and bridges based on DMLS is a certified and registered manufacturing process that is widely accepted on the market. With nearly one hundred systems installed and more than 5 million units manufactured worldwide each year, EOS has established itself as a market and quality leader in the dental manufacturing industry. The basic system EOSINT M 270 Dental allows the productive manufacture of up to 450 units a day.
In cooperation with laboratories and manufacturing services providers, EOS has also been able to optimise the development of systems for economical production of dental models from high quality plastic. Apart from classic fitting models, EOS also offers solutions for the fields of orthodontics and implantology. Alongside the reproducible precision, the big advantage of EOS solutions lies in the heat-resistant, sterilisable, biocompatible polymer PA2105.
EOS M 100: proven EOS quality, high cost efficiency, certified materials
EOS also presented the smaller EOS M 100 system for the first time at IDS. The system provides the dental industry with an entry-level AM system based on metal technology. With its small build volume and 100 mm diameter circular platform, dental laboratories can now economically manufacture high quality crowns and bridges from the certified material EOS CobaltChrome SP2. The system is equipped with a 200 watt fibre laser and guarantees high power stability as well as optimum and constant processing conditions to produce components of the highest quality. The smaller laser spot ensures excellent detail resolution and permits the production of even the finest of dental structures.
Image: Production stages for additively manufactured removable partial dentures. Left to right: dental prosthesis with support structures after AM; with support structures removed; and after completion.