Different Dental Implant Systems
Dental implants are continuing to gain popularity as a superior solution for replacing missing teeth. While dental health has improved in general as a population, patients continue to experience tooth loss. As life expectancy increases and people are able remain active well into their sixties, seventies and beyond, tooth loss becomes increasingly common. Maintaining good oral health is important for a variety of reasons, including maintaining the confidence to smile, ability to eat without limitations and maintain the function of the teeth.
As the population continues to age, including the baby boomer generation, long-term solutions for tooth replacement is gaining momentum. An estimated 3 million people throughout the United States have one or more dental implants. This number is growing by about 500,000 people each year. With increased awareness and improving success rates, the demand for dental implants also continues to increase. Dental implants have an impressive success rate of about 95%.
In addition to increased awareness and success rates for dental implants, the technology for dental implants is also improving. The implant market is expected to see a substantial transformation over the next few years based on some of these modern enhancements.
Dental implants are available to patients in various sizes, shapes and methods which have evolved over time. The most relevant dental implant companies constantly work to make changes to the surface texture, shape, width, and length of their implants in order to deliver a better product and ensure successful outcomes.
While there are more than 100 companies that produce the various implant components, just a major dental implant companies exist which are well-respected globally. These companies are BioHorizon, Dentsply, MIS, Nobel BioCare, Straumann, and Zimmer Biomet.
Various generic implant companies exist who advertise offering cheaper components, however, this can result in long-term issues and challenges with the implant procedure. Fortunately, patients are better educated regarding dental implant technology and often want to ensure their dentist is using products from a well-known manufacturer for their dental implants.
In addition, well-respected dental laboratories are familiar with the top implant manufacturers. In many cases, the technicians are provided with specific training and tools necessary to use these specific components.
The best implant companies make significant research and development investments. When dentists and patients select to use these products, they receive quality, long-lasting components and support in the event of any issues. When the implant device is initially placed in the body, a biological response occurs which results in an exchange of information between the cells and biomaterials.
This process promotes either the acceptance or rejection of the implant and also dictates the number of cells which will populate on the implant surface. Research has proven that osteoblastic cells are able to adhere more quickly to roughened surfaces in comparison to smooth surfaces. The top dental implant companies have focused on this known fact in order to promote improved osseointegration.
While the biomechanical qualities of dental implants which are manufactured by these top companies are clinically researched and transparent with the results, biomechanical qualities of the generic dental implants are not typically researched or transparent with the longevity of the product.
When patients decide which implant system they want to invest in, it can be a daunting task and require a significant amount of time to complete your due diligence. In most implant cases, it is a routine procedure and selected implant system is less critical. However, in more complex situations, such as those which require bone grafting, the type of implant system selected can be quite important.
When reviewing and selecting the implant system to use, the manufacturer’s website can be a helpful resource for an overview of products. In modern dentistry, most dental implant companies work to be a one-stop resource. However, in some cases, it is challenging for one implant system to meet the needs of every patient. In general, it can be advantageous for a dental practice to deal with just a few specific manufacturers. This also allows the dentist to be familiar with the dental implant systems which are offered to their patients.
After the implant system has been selected, there are additional decisions to make as well. The dentist can use cement-retained abutments or screw-retained implants. In addition, both custom abutments and stock abutments can be used for the implant. In most cases, a custom abutment is typically recommended as they can produce superior results esthetically. However, this can vary for each patient.
While most dentists prefer to use titanium implants, zirconia has recently gained popularity. There are also various types of crowns which can be used when the custom abutment is placed.
Cemented Abutments and Screw-Retained Implants
Various factors should be considered when deciding whether to use cement-retained implant crowns or screw-retained implant crowns. Some of these prevalent factors can include the retrievability, how well the peri-implant tissues are maintained, the ease of use, how suitable the crown is with angled implants, and the cost of the crown.
In some cases, an implant crown must be temporarily removed. Some cements are specifically made for implant restorations which claim to be easily retrieved. Some dentists chose to use a temporary cement to secure the implant crowns in place. This can work well, however, results in the crown being less retentive, which is not ideal. Screw-retained implant crown, in comparison, are far more predictable in cases where the crown needs to be retrieved. This is often the case when more abutments are needed. A multi-unit restoration which uses a cement abutment is far more difficult to remove.
Peri-Implant Tissue Maintenance
When the crown of an implant is cemented into place, there is a danger that the excess cement could be forced into the sulcus. When this occurs, there is a potential to damage the peri-implant tissues unless the cement is completely removed. When subgingival cement exists around an implant, it increases the risk of peri-implant mucositis and peri-implantitis. While there are techniques which can be used to properly remove the subgingival cement, there is always a risk that some of the cement could be overlooked. A screw-retained crown, in comparison, does not have this risk and is easily removed as needed for maintenance and cleaning.
The process for placing a screw-retained implant crown is more challenging than a cement-retained crown. This challenge increases when fitting a multiple unit restoration. When cement-retained restoration are used which require multiple abutments, the procedure to fit the restoration does not differ drastically from a routine bridge placement. Placing a screw retained restoration, however, requires additional steps to ensure the framework has passive fit. The restoration should ideally not induce any stress on the implant.
For esthetic purposes, screw holes cannot be placed in the incisal or facial contours of implant crowns. In the event the implant angle is slightly incorrect, then it is necessary to use an angled, screw-retained abutment which results in an increased cost. In this scenario, it is more reliable to use a cement-retained crown using either a custom abutment for a stock angled abutment.
Stock and Custom Abutments
For the implant procedure, either a stock implant abutment or custom implant abutment can be used. It is helpful to be aware of the features associated with both types of abutments to determine which solution best meets the needs of the individual patient.
Stock abutments are available in standardized sizes. They are adequate to be used for both bone and tissue level implants. Stock abutments are specially designed to be user-friendly and make it possible to easily obtain impressions. Stock abutments are often used with cement retained restorations and a more cost-effective choice. Angled and straight abutments are both available and are ideal for tissue level implants which are not visibly obvious.
A main challenge with the stock abutments is their standardized size. As a result of this, the tissue conforms to the shape of the abutment. This type of abutment is not an ideal solution for use within the esthetic zone. This is because it is more difficult for a ceramist to create the correct emergence profile, provide critical tissue support and optimal results for the patient. Another consideration is that with a stock abutment, final margin placement of the crown cannot be controlled. This determination is made by the depth of the implant and the height of the abutment. The dentist may need to spend more time making adjustments in order to achieve the desired fit and emergence profile.
Custom abutments are suitable for both bone and tissue level implants. They can be waxed or milled into the precise shape relative to the crest of the tissue. Several different types of custom abutments can be created from titanium or zirconia, or they will be fabricated from zirconia with a titanium base. When a custom abutment is placed, delivery jigs are used to help ensure the restorative process is smoother and more accurate. While custom abutments are more expensive, they can also offer more predictable esthetics and superior tissue management. This type of abutment is also suitable for both screw retained and cemented crowns. From a clinical perspective, custom abutments can require less time than stock abutments. Meaning they are ultimately a more cost-effective solution as there are less lab fees for modifying stock abutments and fewer clinical resources required during the fitting.