An implant restoration is the final, visible portion of an artificial tooth replacement anchored to the jawbone by a dental implant. This restoration is a custom-made prosthetic, such as a crown, bridge, or denture, designed to look and function like natural teeth. The process focuses on fabricating and affixing this prosthetic after the surgical post has been placed and stabilized within the bone. This solution replaces the entire structure of a missing tooth, from the root embedded in the jaw to the chewing surface.
Understanding the Three Key Components
A complete dental implant system is composed of three distinct parts. The foundation is the implant fixture, a small, screw-shaped post, typically made of biocompatible titanium, surgically placed into the jawbone. This fixture replaces the tooth root and must fuse with the bone through osseointegration, providing a strong, stable anchor.
The second component is the abutment, a connector piece that screws into the top of the healed fixture. The abutment extends above the gum line and acts as a platform for the final artificial tooth. Abutments are customized based on the restoration type and can be made from materials like titanium or zirconia.
The final and most visible part is the restoration, or prosthetic, which is the crown, bridge, or denture that attaches to the abutment. This piece is engineered to fit seamlessly with surrounding teeth and restore chewing function and aesthetics.
Categories of Implant Restorations
The application of implant restorations varies depending on the number of missing teeth. A single-tooth crown is the most common restoration, where one implant fixture is topped with one abutment and one custom-made crown. This approach preserves the integrity of adjacent healthy teeth, unlike traditional bridges.
For patients missing several teeth in a row, an implant-supported bridge avoids placing an implant for every missing tooth. Two or more strategically placed implants support a bridge, which is a unit of connected artificial teeth. This method provides a stable and non-removable replacement.
When an entire arch of teeth is missing, full-arch solutions are used, including fixed hybrid dentures or removable overdentures. A full fixed arch bridge, supported by four to eight implants, provides a permanent, non-removable set of teeth offering maximal chewing efficiency. Removable overdentures attach to two to four implants, providing greater stability than traditional dentures while remaining removable for cleaning.
The Step-by-Step Restoration Procedure
The restoration phase begins only after the implant fixture has fully integrated with the jawbone (osseointegration), which typically takes several months. Once healing is confirmed, the dentist uncovers the implant and attaches the abutment, which extends above the gum tissue. This procedure is often performed using local anesthesia.
The next step involves taking precise measurements and impressions of the abutment and surrounding oral structures. Dentists use both traditional putty molds and advanced digital scanning to create an accurate three-dimensional model. This model is then sent to a dental laboratory, where the final prosthetic is custom-fabricated.
After fabrication, the patient returns for a trial fitting to ensure the fit, bite, and color match are correct. The final placement involves either cementing the crown onto the abutment or securing it with a small screw. Screw-retained restorations offer easier removal for maintenance, while cemented crowns may offer a more seamless appearance.
Materials Used for the Final Crown
The final crown, or prosthetic, is fabricated using materials selected for strength, durability, and aesthetic qualities.
Zirconia
Zirconia, a high-strength ceramic, is popular due to its exceptional fracture resistance, making it suitable for both front and back teeth, as well as long-span bridges. It is highly biocompatible and can be designed to match different levels of translucency.
Porcelain Fused to Metal (PFM)
PFM combines a strong metal alloy base with a porcelain outer layer for aesthetics. PFM crowns offer high durability and have a long clinical track record, often being used in areas that require significant biting force. However, the underlying metal frame can sometimes create a dark line at the gum margin, presenting an aesthetic challenge.
Emax (Lithium Disilicate)
Emax, or lithium disilicate, is a glass-ceramic material favored for its outstanding natural aesthetics and translucency, often making it the preferred choice for front teeth. While not as strong as monolithic zirconia, Emax is suitable for most single-unit restorations and provides a highly lifelike appearance.
The selection of the material is determined by the crown’s location in the mouth, the patient’s bite forces, and aesthetic priorities.