Inlays / Onlays
When a tooth has lost a significant amount of its structure, a possible treatment is the inlays or onlays. The inlay fits exactly inside the prepared cavity while the onlay also covers the chewing surface. Both are usually manufactured in a dental laboratory or dental clinic based on accurate dental models providing adequate protection when a simple filling fails.
Porcelain material has been used for years in the manufacture of inlays. The result can be as excellent and natural as a live tooth, but it requires increased dental preparation compared to other options. Abrasion between teeth due to hardness of porcelain is a matter for thought when the masticatory forces are increased.
Composite resin is an alternative to natural tooth colors and it is usually processed specifically in the laboratory under pressure to provide the required standards of durability and strength. Its duration is similar to porcelain inlays but it is less abrassive than the first option.
With the use of digital dentistry as well as special CAD / CAM processing systems (Computer Aided Design / Computer Aided Manu-factured) it is possible after digital design on the computer to cut zirconium with special features for perfect application without tension, quality of construction, durability and aesthetics compared to other options. Studies suggest that its fracture resistance is higher than any other material in laboratory conditions. The techniques are very new and specify the evolutionary course of dentistry today.
CAD / CAM (Computer Aided Designed / Computer Aid-ed Manufactured) digital systems are used in this case as well, and an inlay/onlay is made which incorporates a post a core and an inlay when the tooth is endodontically treated.
The main advantage of the procedure is that only one piece is manufactured and not independent parts as with conventional methods (post, core, inlay). So, the construction has increased durability which is especially important with endodontically treated teeth, which present an increased danger of cracking due to the lack of vitality.