Dental implants have revolutionized the art and science of replacing lost teeth. For years, the only options for missing teeth were bridges and dentures but over the last forty years, implants have become the standard of care. An implant replaces the root of the tooth and fuses with the underlying bone to provide a strong foundation for a replacement tooth or bridge that matches the natural teeth.
“An implant fused to the bone is the closest we can get to replicating a natural tooth,” says Dr. Robert Holt of the Florida Institute for Periodontics & Dental Implants. “It is stable, has the look and feel of natural teeth, and doesn’t affect or alter the adjacent teeth. Over the years, implant technology has continued to advance and today, with the addition of ceramic implants to the traditional metal, implants have a success rate of close to 98%.”
Modern implants date to an accidental discovery in 1952 when a Swedish doctor named Per-Ingvar Branemark noticed that when titanium comes in contact with bone and is left undisturbed it becomes integrated with the bone and cannot be removed. This process, called osseointegration, became the basis for dental implants as further research showed that the body could tolerate the long-term presence of titanium and it could be used as a foundation for artificial teeth. Dr. Branemark died in 2014 but his discovery has helped millions of people avoid the discomfort and inconvenience of dentures.
Today, titanium alloys remain the standard for metal implants. Titanium is lightweight, well tolerated biologically and when combined with small amounts of other metals, extremely durable. It is not unusual for titanium implants to function without complications for thirty years or more and 95% of implant placements today are titanium alloys. The primary alternative to titanium is provided by the more recent development of non-metal ceramic implants. The most common and strongest ceramic implants are made of zirconium, best known in its crystalline form, called cubic zirconia, for its resemblance to diamonds. For dental purposes, it is used in the form of zirconium oxide, which is extremely strong and durable, highly resistant to fracture and heat, and integrates well with bone.
“Given the proven success of titanium implants, why choose ceramic?” Dr. Holt asks. “One reason is that a small number of people are sensitive to metal and titanium may trigger irritation or an allergic reaction. And some people simply prefer not to have metal in their bodies. Zirconium is an inert material that is completely non-reactive with human tissue. There are also differences between the two materials that argue for one over the other based on an individual patient’s requirements.”
One of those differences is aesthetic. Zirconia is white, more like natural teeth than metallic titanium. Patients with thin gums or receding gums may prefer the more natural look of zirconia to the slightly gray cast of their gums with titanium, particularly on front teeth. Another difference is design. Titanium implants usually consist of two components joined by a screw – a cylindrical post that is embedded in the jaw and a connector that protrudes from the gum and holds the crown. The advantage of this design is versatility in placing the implant but there is the possibility that under the pressure of chewing the two pieces could shift, providing an opening for bacteria and ultimately affecting the success of the implant. Zirconia implants are designed as a single piece, making them more secure but limiting the ways in which they can be used.
Dr. Holt concludes: “Advances in composition and design and the clinical experience of millions of patients have brought the science of dental implants to the point where we can devise a strong solution for virtually any patient and any situation, from a single tooth to an entire mouth. By helping people eat, talk, and smile naturally, dental implants promote physical as well as psychological well-being.”
Robert L. Holt, D.M.D., manages patients with complex periodontal-implant-prosthetic problems, specializing in bone and tissue regeneration, periodontal-prosthetics, esthetics, and dental implantology.