Acrylics in dentistry:
An indispensable part of everyday work at the laboratory
Acrylics are part of everyday laboratory work, e.g. for veneers, dentures, splints, fixed restorations and auxiliary materials such as individual trays or bite plates.
Acrylics in dentistry:
An indispensable part of everyday work at the laboratory
Acrylics are part of everyday laboratory work, e.g. for veneers, dentures, splints, fixed restorations and auxiliary materials such as individual trays or bite plates.
Depending on the processing method, acrylics are divided into chemoplastic and thermoplastic categories. The materials harden through chemical setting reactions (e.g. heat, UV light, pressure pot). As a rule, synthetic materials are “patient”, but processing errors can cause lasting damage to the material (e.g. overheating). This is why work should always be carried out using the best rotary tools available.
On the other hand, dental technicians in plastics technology are faced with the challenge of balancing cost-effectiveness and quality. The right cutters should be at hand, especially in cases where speed is of the essence. Whether new restorations, relinings or repairs – with the right tool, time becomes an important success factor.
Tungsten carbide burs for finishing dentures
Tungsten carbide burs with staggered toothing are particularly suitable for finishing dentures. For example, cutters with ACR toothing are recommended for rough shaping after deflasking. The dual bur EQ, which is provided with both a coarse and a fine toothing, enables effective processing of the denture margins and smoothing of the interdental areas, thus eliminating the need to change tools during work. This bur combines two worlds: A fine-toothed tip and a coarse-toothed toothing at the end of the working part. Carbide burs with FSQ toothing (fine, easy-cutting, cross-cut) and tapered geometry are ideal for recessing the labial and buccal frenula.
The serrated diamond disc is particularly suitable for interdental work that requires special care. The disc is flexible, coated on both sides and enables targeted separation and/or contouring thanks to its extra-fine diamond grit. Diamond burs in the shape of a small ball are helpful for grinding the teeth in the occlusal area of the denture in accordance with the grinding rules. Interfering areas can be removed without impairing the relief of the occlusal surface. Special acrylic polishers are available for polishing the acrylic denture in order to smooth the surfaces. These are available in coarse, medium and fine grit for pre-polishing, polishing and high-gloss polishing.
The work on soft acrylics
Work on soft acrylics can be tedious. Due to the difficult machinability of soft acrylics, it is difficult to shape the workpiece efficiently. The ideal solution are the cutters with GSQ toothing. Made of tungsten carbide, these cutters have been specially developed for machining soft acrylics, e.g. silicone as well as special materials that remain soft. With its large chip spaces, small number of blades and cross-cut toothing, this high-performance toothing offers clear advantages during use:
Easy and precise surface shaping, effective cutting and removal of great quantities of material as well as the creation of an optimum surface quality. The cutters with GSQ toothing are available in various geometries (e.g. pear-shaped, pointed). A ceramic version is also available. The fine-toothed FSQ cutters, also with cross-cut toothing, ideally complement the range. They are particularly suitable for transitions from hard to soft acrylic (e.g. relinings).
Tools for finishing tooth-colored composite veneers
Tungsten carbide burs can be used to give tooth-colored composite veneers a fine finish. However, it should be borne in mind that abrasive instruments with too coarse a structure will create rough surfaces and leave scratches. In order to avoid this, the UK toothing is the ideal solution. Thanks to their special double-ground toothing, the cutters produce an ideal surface texture that can be polished quickly and easily.
The tools are available in many different geometries and sizes for artistic and detailed finishing. Abrasive discs (fine, ultra-fine, rigid, flexible, with and without toothing, etc.) for separating and contouring are available in various sizes – both single-sided and double-sided. Special polishing wheels and brushes are then used to give the acrylic veneer a glossy finish.
Trimming of splints
The trimming of splints (according to a deep-drawing technique or digital production) requires a certain finesse. You need the right tool for cutting the splint out of the thermoforming plate as well as for trimming the edges. Constant “clogging up” of the cutters is extremely annoying. Komet has put together the starter kit 4676A for work on splints. The set consists of seven instruments.
First of all, the vacuum form cutter is used to cut the thermoformed splint off the plaster model. The ceramic cutters included in the set are ideal for removing excess material and trimming the splint edges. The silicone-impregnated fiber fleece wheel is then used to quickly round off and smooth the splint edges. In the final step, the acrylic polisher gives the splint a glossy finish.
