Inlays and Onlays – What are they and how are they useful?

Inlays and Onlays are types of dental restorations. Both can be made from porcelain, gold, or a combination of both. Porcelain-fused-to-metal (PFM) is another type that consists of porcelain fused to a metal substructure. Inlays and Onlays have been used for decades by many dentists Ryde as a common restoration option for many teeth. They provide excellent durability and resistance to wear because they cover most of the occlusal surface area of a tooth. Onlays are designed to cover 1/2 to 2/3 of the biting surface of a tooth. At the same time, inlays are thicker restorations that may also involve replacement enamel from adjacent teeth if needed depending on the tooth and restoration size. 

An inlay usually covers one or more cusps but does not encircle the entire circumference. An onlay is traditionally used to provide coverage for an entire cusp, though some new Onlays are being created that cover up multiple cusps instead of just 1/2 to 2/3 of the biting surface of a tooth. Porcelain veneers are commonly used for teeth with large restorative cavities. These thin shells can be applied to restore decayed areas on front teeth; however, they cannot be applied to back (posterior) teeth because there is not enough tooth left after preparation due to their larger size requirements than other types of restorations. 

An inlay is often recommended when the decay involves two or more adjacent cusps because it covers all of them and does not leave any remnants. An onlay is usually required if the tooth has had a root canal treatment or needs replacements of its enamel with one that closely matches the colour of natural teeth. In addition, it provides better coverage for larger cavities than an inlay. Onlays are also used to replace fractured teeth, protect decayed teeth from further damage due to occlusal forces, or restore badly damaged teeth so they can receive crowns later on. 

When selecting a type of restoration for your tooth(s), it’s important to discuss these options with your dentist so that you may be presented with the most beneficial choice for your specific case. 

Which one is better, inlay or onlay? Both of these safeguard your teeth from further decay while restoring your teeth’ original function and shape. The major difference between the two is their size. Onlays cover more tooth surfaces than inlay. An inlay is used to restore 1 or 2 cusps of a tooth, while an onlay restores many points together. In general, dental restorations should be conservative so that adjacent natural teeth aren’t damaged due to excessive enamel and/or dentin removal during preparation procedures. 

Which one is better? 

It depends on your case and how much damage has been done to your teeth. If you need to restore several cusps together, an onlay is your best option. Inlays can also restore several cusps, but they won’t look as natural and beautiful as onlays. An inlay covers 1 or 2 cusps of a tooth while an onlay restores many other cusps together.