What You Need To Know About Acetal Resin

Today’s dentists are increasingly prescribing metal-free, removable partial dentures: with acetal you can now offer them a digitally produced, tooth-borne framework. Your lab can also offer your doctors thinner, more hygienic, virtually unbreakable acetal bite splints. Smile-enhancing, patient retrievable acetal anterior bridges provide patients with an affordable alternative to other permanent treatment options such as veneers or orthodontia. It can also lead them to choose those other options some time in the future. Best of all, acetal is a great material for minimally invasive dentistry. This can certainly increase patient acceptance of recommended treatment plans.

ACETAL RESIN PROPERTIES

• High tensile and flexural strength

• Fatigue resistance

• Low friction

• Low moisture absorption

• Excellent dimensional stability

AVAILABLE IN Vita 16 Shades, Clear and pink shade

What is Acetal Resin?

Acetal (scientific name polyoxymethylene) is a 99.9% pure, highly crystalline millable thermoplastic. What makes this copolymer special is that this material is flexible when thin, but becomes more rigid as it becomes thicker, making it an ideal material for fabricating a variety of tooth-retained removable appliances. The material absorbs virtually no water, delivering long-lasting performance and making it less likely to develop stains or odors. Think of Acetal like a much-improved PMMA, but stronger and more flexible than PMMA. Acetal allows you to make a thinner, more flexible appliance, and it can engage natural undercuts in teeth for maximum retention and patient comfort. Acetal has been used in dentistry worldwide successfully for decades in injectable form. Now this super-material comes in millable form: acetal mills cleanly and quickly (dry or wet), so you can take advantage of unused capacity in your CAM machines. With the high predictability a digital workflow gives you, you can count on acetal to give your doctors and their patients esthetic, excellent fitting, durable removable appliances at a great value.

Using existing software, strategies, and tools

You should already have everything you need in your lab to begin using acetal. Both 3Shape and Exocad now provide CAD solutions that support all of the indications acetal resin can be used for. This results in reduced cost, reduced labor, improved consistency and accuracy, and shortened manufacturing cycles.

• Can be milled both dry and wet

• Compatible with any dental mill that accepts a 98.5 mm disc

• Technicians can use either a Mono or PMMA milling strategy

• Cuts very easily, resulting in minimal tool wear

• Can be easily polished to a beautiful luster due to its density.

A Variety of Indications

PARTIAL DENTURE FRAMEWORKS

Perhaps the most viable acetal product is partial denture frameworks. Unlike cast metal partials, acetal is a limited thermal conductor, resulting in greater comfort when eating or drinking hot or cold foods. Because acetal is colored like a natural tooth, it is more esthetic than metal when used for clasps. Having an easily milled material, one can CAD a delicate partial denture frame and mill it in most dry 5-axis mills. According to research, patients are twice as likely to lose the tooth adjacent to a partial denture than any other tooth. However, because acetal is much more flexible than CrCo, it is kinder to adjacent teeth. Lastly, using acetal is much less labor intensive compared to fabricating denture frameworks from cast metal (due to cast metal requiring so many steps to create, as well as all of the chemical reactions it causes that can play havoc with accuracy and fit). When moving to milling acetal and its all-digital workflow, these problems are dramatically reduced.

LONG-TERM PROVISIONAL RESTORATIONS

Acetal is also a viable alternative to long-term provisional restorations because it is stronger than PMMA and very kind to opposing dentition. Being water resistant, there will be less water absorption and staining with acetal as compared to PMMA. Plus, clinicians can use the cement of their choice.

BITE APPLIANCES

Bite appliances made from acetal are nearly unbreakable and become very profitable when manufactured in an automated workflow. This tooth-colored appliance can be milled thinner, providing increased patient comfort and thus improved compliance with treatment. In addition, the retention can be easily adjusted because the acetal will flex over undercuts.