Dental Laboratory Technology
Dental laboratory technology is the science and craft of creating dental prostheses. It involves artistic talent, aptitude for precision work, good eyesight, and a high degree of manual dexterity. Knowledge of CAD/CAM computer programs, digital cameras, and digital imaging systems is also required.
Preventive education has decreased the incidence of dental caries. Better dental health means that the demand for dentures has declined, while the need for dental prostheses and cosmetic procedures has increased.
Dental laboratory technicians are sought by dental laboratories, private dental practices, and medical institutions. These skilled craftspeople are part scientist, part artist, and part engineer. They must have manual dexterity, good eyesight, and a penchant for detailed, precision work.
Dental laboratory technicians create a variety of dental prostheses including crowns, bridges, artificial teeth, partial dentures, and complete dentures. They also prepare inlays—ceramic or resin structures that are cemented into a prepared tooth. Technicians also create onlays from those same materials which fit over the tooth but do not cover the tooth completely like a crown. In large laboratories, dental technicians may specialize in a single type of restoration, such as crowns or partial dentures. Some laboratories have ceramists who specialize in creating ceramic restorations of every type.
In order to design and craft these prostheses, a dental technician prepares wax diagnostic models from patients' mouth impressions. These wax models are finely detailed sculptures of the mouth, showing how the restoration will look and how it will work. From these, the prostheses are cast in investment molds through an ancient bronze casting and jewelry method, called the lost wax technique.
The investment mold is poured around the wax model of the prosthesis and is fired. The wax melts and drains out of the investment mold, leaving behind a durable mold into which the technician can pour a casting material. Restorative casting materials can be metals (gold, silver, amalgam), resins, or ceramics. These are poured into the investment mold to craft individual teeth, crowns, and other dental prostheses.
New computer applications are making the restoration process faster, more accurate, and more comfortable. Implant and crown design is often time consuming, requiring several appointments to ensure a proper fit. Duplication technology (e.g. Geomagic Studio from Raindrop Geomagic of Morrisville, NC) uses 3-D scanners to scan a patient's mouth. This duplicates the shape, thickness, and color of the natural teeth. This information is processed through CAD software and used to generate a digital prosthesis that is virtually inserted into the digital image of the patient's mouth to check for an accurate fit. The dental prosthesis is then crafted in real materials and fitted into the patient's mouth.
Dental laboratory technicians work mainly in dental laboratories. These are usually independent businesses, with one technician out of five owning his or her own laboratory. Some laboratories may also be connected with a dentist or a team of dentists, to create a one-stop service for patients. Some technicians work in hospitals or institutions which provide dental services to in-house patients, e.g. VA hospitals.
Laboratory facilities are clean, well lit, and carefully ventilated. Workstations may be equipped with computers, grinding equipment, polishing machines, and a variety of tools for fine detailed work. Most dental laboratory owners keep their facilities equipped with state-of-the-art tools, equipment (including a dental kiln), and materials. They also provide continuing training for their technicians in current procedures, techniques, and material use.
Education and training
Though most dental laboratory technicians learn while working on the job in the laboratory, many are now seeking professional training at junior colleges, dental schools, and vocational/technical institutions before seeking employment. Some dental schools offer course work in dental laboratory technology. In any event, technicians will still need to train on the job in order to learn the techniques and styles of a particular dental laboratory.
Early tasks on the job may be relatively menial in contrast to the skills the technicians will display later for the laboratory. They may prepare dental impressions or fire already prepared crowns or dentures. After three or four years of training, technicians are then able to design and craft dental prostheses for patients.
The ADA Commission on Dental Accreditation has accredited 34 programs in dental laboratory technology. Classroom instruction includes oral anatomy, dental materials science, fabrication procedures, computer software applications, digital imaging, and ethics. Students
Certification is available in some states through the National Board. This is voluntary and not necessary to work in the profession. Five areas of certification are available; crowns and bridges, ceramics, partial dentures, complete dentures, and orthodontic appliances.
Advanced education and training
Most dental schools offer specialization in prosthodontics. A prosthodontist is a dentist who does only dental restorations. Usually, prosthodontists have three or more years of education beyond their DDS (doctor of dental surgery) degree. They may supervise full mouth restorations or single crowns. They are often able to oversee the manufacture and fitting of fixed bridges, dentures, implants, or a combination of these prostheses. Periodontists, specialists in gums and bones, and oral and maxillofacial surgeons may also fit implants into the jaw. They also are required to have three or more years of education beyond their DDS degree.
More people in their retirement years have full, (or almost full) sets of teeth and no longer require complete dentures in old age. They are, however, requesting more enhancements to their appearance and more prostheses to improve their ability to chew and enjoy their food. Employment for dental laboratory technicians is favorable and may increase as the demand for prosthetic and cosmetic services increases with the aging of baby boomers.
Shillingburg, Herbert T., Jr., Sumiya Hobo, and Lowell D. Whitsett. Fundamentals of Fixed Prosthodontics. Chicago: Quintessence Publishing Co., 1997.
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Academy of General Dentistry, Suite 1200, 211 East Chicago Avenue, Chicago, IL 60611. (312) 440-4300. <http://www.agd.org>.
American Dental Association, 211 East Chicago Avenue, Chicago, IL 60611. (312) 440-2500. <http://www.ada.org>.
National Association of Dental Laboratories, 1530 Metropolitan Blvd., Tallahassee, FL, 32308. (800) 950-1150. <http://www.nadl.org>.
"The Art & Science of Dental Laboratory Technology." National Association of Dental Labs. <http://www.nadl.org/artsci.htm>. (Accessed May 1, 2001.)
"Dental Laboratory Technology." ADA Career Brochures. <http://www.ada.org/prf/ed/careers/brochures/absted.html>. (Accessed May 1, 2001.)
"Dental Laboratory Technicians." Occupational Outlook Handbook. <http://www.stats.bls.gov/oco/ocos238.htm>. (Accessed May 1, 2001.)
Bridge—An appliance of one or more artificial teeth anchored by crowns on the adjacent teeth.
CAD/CAM—A computer-aided design and manufacturing package for the fabrication of dental prostheses.
Complete denture—A full set of upper or lower teeth, mounted in a plastic base. Dentures are also called false teeth.
Crown—A protective shell that fits over the tooth.
Dental caries—An infectious disease of the teeth in which microorganisms convert sugar in the mouth to acid that erodes the tooth structure.
Inlay—A filling that is made outside of the tooth and then cemented into place.
Onlay—A restoration that covers the upper surface of a tooth. It is bigger than a filling but smaller than a crown.
Janie F. Franz