Dental implants offer a reliable method for replacing missing teeth, serving as artificial tooth roots surgically placed into the jawbone. They restore a person’s ability to chew and can significantly improve cosmetic appearance. Understanding the materials used in these devices is important, as the choice influences the implant’s success, longevity, and how well it integrates with the body.
Understanding Dental Implant Structure
A typical dental implant system comprises three primary components that work together to replace a missing tooth. The first part is the implant body, often referred to as the post or screw, which is surgically inserted into the jawbone and acts as the artificial tooth root. Connected to this post is the abutment, a small connector that extends through the gums and provides a stable base for the final restoration. The third component is the dental crown, which is the visible, artificial tooth designed to replicate the appearance and function of a natural tooth. Each of these distinct parts is manufactured from different materials, chosen for their specific properties and roles within the implant system.
Materials for the Implant Body
The implant body, embedded directly into the jawbone, is typically made from materials that can fuse with bone in a process called osseointegration. This fusion provides a stable, long-lasting foundation for the replacement tooth. Titanium has long been the standard material due to its high strength, resistance to corrosion, and exceptional biocompatibility, meaning it is well-tolerated by the body. Bone forms a strong bond with titanium, contributing to its high success rate.
Zirconia, a white ceramic material, is another option gaining prominence. It offers a metal-free alternative, appealing to patients with metal sensitivities or those desiring a more natural appearance, as it eliminates the risk of a dark line showing through the gum tissue. Like titanium, zirconia is biocompatible and can achieve osseointegration. While strong, zirconia implants may be more susceptible to chipping or fracturing under extreme pressure compared to titanium, and their long-term success data is still evolving.
Materials for the Abutment
The abutment links the implant body and the dental crown, protruding above the gum line to support the visible restoration. Titanium remains a common choice for abutments due to its strength, durability, and biocompatibility. It withstands significant chewing forces, making it suitable for posterior implants. However, its metallic color can sometimes be visible through thinner gum tissue, affecting aesthetics in highly visible areas.
Zirconia abutments offer an aesthetic advantage, as their tooth-colored ceramic blends seamlessly with natural teeth and eliminates metallic show-through. This makes zirconia preferred for front teeth where appearance is a primary consideration. While strong, zirconia can be more prone to fracture than titanium under certain conditions. Gold alloy abutments are another durable and biocompatible option, often used for precise fit. Newer options like polyether ether ketone (PEEK) are emerging for their lightweight properties and flexibility.
Materials for the Crown
The dental crown is the visible part of the implant, designed to restore both function and aesthetics, offering the widest range of material choices. Porcelain-fused-to-metal (PFM) crowns have a long history of use, combining a metal base for strength and a porcelain layer for a tooth-like appearance. PFM crowns are durable and can be used for both front and back teeth, offering a balance between strength and aesthetics, though the metal base can sometimes become visible at the gum line over time.
Full zirconia crowns are another popular choice, known for their exceptional strength, durability, and natural appearance. They are highly resistant to wear and chipping, making them a good option for molars that endure significant chewing forces. Zirconia crowns can be color-matched to natural teeth and offer a metal-free restoration, providing aesthetics and resilience.
Emax, a type of lithium disilicate ceramic, is highly regarded for its superior aesthetic qualities, closely mimicking the translucency and light reflection of natural tooth enamel. Emax crowns are strong and durable, resisting chipping and fractures. They are often chosen for highly visible areas due to their lifelike appearance and ability to blend seamlessly with surrounding teeth.
Acrylic and composite resin crowns are sometimes used, particularly as temporary restorations due to their affordability and ease of fabrication. While color-matched, they are generally less durable and more prone to wear and discoloration compared to ceramic or metal-based options. The selection of crown material depends on factors such as the implant’s location, the patient’s aesthetic expectations, biting forces, and budget.