This news article was originally written in Spanish. It has been automatically translated for your convenience. Reasonable efforts have been made to provide an accurate translation, however, no automated translation is perfect nor is it intended to replace a human translator. The original article in Spanish can be viewed at Dientes plásticos 'Made in Germany'

3000 Dens: first plastic teeth by moulding by injection

Plastic teeth ' Made in Germany'

Drafting Interempresas01/07/2011

July 01, 2011

Dentures no longer have to be expensive or of poor quality: the young company Dens3000 has managed to produce teeth for prosthesis from thermoplastic PMMA molding technique by injection. These plastic teeth ' Made in Germany' meet the maximum requirements of quality and without the need for subsequent prosecutions. Together with the Arburg experts developed and patented a special solution of two components.

"My intention is to bring to market a plastic tooth of high quality, that is at once economic and that can make interesting dentures also for countries of Eastern Europe from the East and China," he explains his idea of business Reinhard Lohse, medical physicist and founder of Dens3000. Hartmut Schmitt has hired the Chief of production to bring this vision into practice. This expert in the transformation of plastics and moulds creator has 30 years of experience in the molding by injection.

144 different teeth of PMMA for prosthesis.

"From the outset Arburg was open to listen to our problems, which go beyond the world of the moulding by conventional injection", says Reinhard Lohse. Hartmut Schmitt explains particularities: "For me the product is not any tooth itself, but a complex molded component with many surfaces free conformation, recesses and a surface whose quality is subject to the highest standards".

Together with the Arburg project Department, manufacturer of molds and construction Office was designed to fit Dens3000 an injection process of two-component with automation system and adapted the machine exactly to your special requirements. The art of producing a tooth of top quality plastic, which can turn demolding certainly lies in the accurate adaptation of the material, the mold and the machine.

In just 30 seconds an Allrounder 520 A produces eight units.

Given that will produce high precision parts, whose components just weigh between 0.1-0.73 g, the choice fell on an electrical injection machine. An Allrounder 520 A with clamping force of 1,500 kN and size 70 injection two units proved the ideal machine. His practical know-how, Arburg experts developed a special cylinder that transports and homogenised optimally used PMMA.

Ten times cheaper PMMA tooth

To make the teeth look as natural as possible are produced from two plastics of different hardness and colours. The perfect look is obtained only after the combination of the basic body with enamel. The PMMA subjected to repeated modifications and the teeth were tested in university clinics. "In a manner contrary to as it is the case with the plastic teeth made from the conventional extrusion of thermosetting process, our products are not vulnerable to dental boards or to the appearance of fissures", says Reinhard Lohse, "and that at a price five to ten times cheaper".

Dens3000, Reinhard Lohse (left) Manager, and head of production Hartmut Schmitt have succeeded for the first time producing plastic teeth for prosthesis through the process of molding by injection.

Four 8-cavity molds are used to reproduce in full the 28 teeth of teeth. The program offers a total of 144 teeth model in 16 different shades, three sizes and different shapes to individualized incisors. Injection weight is between 2.5 and 5.6 grams depending on the type of tooth. After a cycle time of 22 to 30 seconds, the eight injected parts are removed by a system of robot Multilift H and deposited by cavities.

The Allrounder 520 A model is capable of producing 8 teeth in a period of time between 22 and 30 seconds

The system of robot Multilift H deposited teeth by cavities for its cooling.

The exact positioning is responsible for a finger at the "root", which has the same form for all the teeth. It also has an individual identification. During the next cycle of injection molding teeth cooled and are separated by a system of flexible tubes. For quality control are extracted evidence of teeth every two hours. This control includes, for example, a check of the colour and measurements of hardness and weight. Durability of teeth eventually integrated in the prosthesis is of the order of five to ten years.

Twenty million teeth per year

Since March 2010, Hartmut Schmitt has carried out several hundred trials in its production centre in Kusel (Rhineland-Palatinate). The optimization, the development of the mould and sampling lasted about a year. Meanwhile the process is now ready for production in series and soon will begin production. Four electric Allrounder for two components will be then in three shifts and the 24 hours of the day 20 teeth million per year. To minimize the time inoperative, Dens3000 has closed a maintenance contract with Arburg which includes preventive maintenance at regular intervals.

Infobox:

• For the first time teeth of PMMA: thermoplastic instead of thermostable ceramics

• High quality of the product without further processing

• Injection of several patented components

• Eight different types of tooth by cycle (weight of the piece injected 0.24 to 1.1 g)

• A single machine can producer up to 8 million teeth per year

• Cooperation with the TU Kaiserslautern materials technology Institute and the University clinics of Regensburg and Homburg/Saar