What is a dental prosthesis?
Depending on the number of teeth missing and their position in the mouth, your dental prosthesis can look very different but always consist of:
A crown or bridge: A crown is an artificial tooth whereas a bridge is a set of connected artificial teeth. A bridge makes it possible to use fewer implants than the number of missing teeth.
One or more abutment(s): An abutment connects the crown or bridge to the implant. One abutment is needed for each implant.
There are a number of different options available to you, depending on whether you are missing one tooth, a few teeth, or all of your teeth. If you are interested in knowing more about your dental implant prosthesis options and how they compare with non-implant solutions, see a comparison of treatment options here.
How does a prosthesis work?
The crown or bridge can either be cemented onto the abutment outside or inside the mouth. When it is cemented outside the mouth it is called a screwed-retained crown or bridge and when it is cemented inside the mouth it is called a cemented-retained crown or bridge. It has been shown that a cemented-retained crown or bridge carries a higher infection risk [1].
There are so-called provisional prostheses that are placed on the day of surgery. These are only made to last six to 12 months, during the healing period. A final (or definitive) prosthesis, however, is placed once healed from the implant placement surgery and is made to last much longer.
Continue reading to discover:
The Importance Of Prosthetic Design
How Long A Prosthetic Can Last
How is a dental prosthesis made?
Your dental prosthesis is designed and manufactured by a dental technician, who in turn supplies it to your dentist.
Your dentist will take a physical or digital impression of your mouth with dental alginate or with the use of an intra-oral scanner. This information is sent to the dental technician who normally will prepare a provisional prosthesis for the day of surgery and a final prosthesis for when the healing is completed (this usually occurs three to nine months after surgery).
The dental technician can choose between three technologies to manufacture the prosthesis:
Prefabricated Prosthetics
Prefabricated (also known as off-the-shelf) prostheses are products mostly adapted in the patient’s mouth. They are quick to adapt, and their strengths and aesthetics are acceptable for provisional teeth but are not often used for the final prosthetic.
Porcelain Fused Metal (PFM) Prosthetics
Porcelain Fused Metal is the traditional, handcrafted way to prepare custom-made prosthetics. This tedious approach provides a prosthetic that can be very aesthetically pleasing. However, it is not as effective as CAD/CAM prosthetics.
CAD/CAM Prosthetics
Computer-Aided Design (CAD) and Computer-Aided Manufacturing (CAM) prosthetics are considered state-of-the-art prostheses by modern standards. This technology allows dental technicians to prepare a custom-made prosthesis that is strong and esthetically pleasing, with a very high level of precision.
Why is the design of a dental prosthesis so important?
Prosthesis work is complex and challenging in terms of design, as the final prosthesis needs to sit perfectly on the implant, be the right size and shape for your mouth, be esthetically pleasing, and be durable. This is essential for the longevity of the dental implant system, as well as for your comfort and ability to chew and speak.
A wide number of prosthetic materials are available, allowing the dentist and the dental technician, to find the most appropriate options for all patients’ budgets, as well as their esthetic and functional requirements. However, one challenge that exists when designing a prosthesis is whether to make it strong, aesthetic, and/or affordable due to specific material limitations. If a prosthesis is located at the back of the mouth it needs to be very strong, whereas if the tooth to be replaced is visible when the patient smiles the aesthetics become more important. See here for a more detailed explanation of the different prosthetic materials.
Increasingly, when dentists plan the placement of dental implants, they plan it to be in the best axis possible of the prosthesis and where the bone volume is satisfactory. In addition, the dental technician employs a high level of precision to design and manufacture the prosthesis to ensure the best possible fit. Any micro-motion could lead to loosening or damage to the prosthesis and/or the dental implant.
How long does a dental prosthesis last?
A provisional prosthesis is only made to last six to 12 months, during the healing period, whereas a final prosthesis is made to last much longer.
The final prosthesis is designed to stay in your mouth for many years. Studies show a five-year survival rate of at least 96% and close to 90% at ten years [2]. The longevity of the prosthesis (and its implant) is dependent on the connection quality between the implant and the abutment.
The stability and performance of the complete implant system are based on high-precision engineering, which is hard to achieve by simply using copied original abutments. These copied or ‘compatible’ abutments fit into an implant but problems may arise on a microscopic level [3], where micro-gaps could lead to failures [4][5]. For example, the abutment screw could loosen [6][7][8], the prosthesis could be damaged or you could even suffer an implant fracture. Despite these differences in quality, choosing a compatible prosthesis rather than an original one is often motivated by marginal cost savings.
A simple way to improve your chances of having a long-lasting dental implant treatment is to favor solutions of the same brand as your dental implant [9][10][11].
How much does a dental prosthesis cost?
The price of a prosthesis accounts for a small amount (5 -10%) of the total dental implant treatment cost and varies based on many factors. Despite the marginal cost of the prosthesis, it plays a highly significant role in the long-term performance of the entire restorative system.
It must stay esthetic, durable, comfortable, and strong for good mastication, which makes a convincing case for investing in a high-quality prosthesis.
To learn more about the overall price of a dental implant treatment click here.
[1] Staubli N, Walter C, Schmidt JC, Weiger R, Zitzmann NU. Excess cement and the risk of peri-implant disease – a systematic review. Clin Oral Implants Res. 2017;28(10):1278-1290. doi:10.1111/clr.12954
[2] Jung RE, Zembic A, Pjetursson BE, Zwahlen M, Thoma DS. Systematic Review of the Survival Rate and the Incidence of Biological, Technical, and Aesthetic Complications of Single Crowns on Implants Reported in Longitudinal Studies With a Mean Follow-up of 5 Years. Clin Oral Implants Res. 2012 Oct;23 Suppl 6:2-21.
[3] Mattheos N, Larsson C, Ma L, Fokas G, Chronopoulos V, Janda M. Micromorphological differences of the implant-abutment junction and in vitro load testing for three different titanium abutments on Straumann tissue level implants. Clin Oral Implants Res. 2017 Apr 11.
[4] Karl M, Irastorza-Landa A. In Vitro Characterization of Original and Nonoriginal Implant Abutments. The International Journal of Oral & Maxillofacial Implants. 2018;33(6):1229-39.
[5] Gigandet M, Bigolin Implant with original and non-original abutment connections. Clin Implant Dent Relat Res. 2014 Apr;16(2):303-11. doi: 10.1111/j.1708-8208.2012.00479.x.
[6] Kim SK, Koak JY, Heo SJ, Taylor TD, Ryoo S, Lee SY. Screw loosening with interchangeable abutments in internally connected implants after cyclic loading. Int J Oral Maxillofac Implants. 2012 Jan-Feb;27(1):42-7.
[7] Krishnan V, Tony Thomas C, Sabu I. Management of abutment screw loosening: review of literature and report of a case. J Indian Prosthodont Soc. 2014;14(3):208-214.
[8] Jung RE, Zembic A, Pjetursson BE, Zwahlen M, Thoma DS. Systematic review of the survival rate and the incidence of biological, technical, and aesthetic complications of single crowns on implants reported in longitudinal studies with a mean follow-up of 5 years. Clin Oral Implants Res. 2012 Oct;23 Suppl 6:2-21.
[9] Karl M, Irastorza-Landa A. In Vitro Characterization of Original and Nonoriginal Implant Abutments. The International Journal of Oral & Maxillofacial Implants. 2018;33(6):1229-39.
[10] Gigandet M, Bigolin Implant with original and non-original abutment connections. Clin Implant Dent Relat Res. 2014 Apr;16(2):303-11. doi: 10.1111/j.1708-8208.2012.00479.x.
[11] Kim SK, Koak JY, Heo SJ, Taylor TD, Ryoo S, Lee SY. Screw loosening with interchangeable abutments in internally connected implants after cyclic loading. Int J Oral Maxillofac Implants. 2012 Jan-Feb;27(1):42-7.