Dental filling, Inlay, Onlay, and overlay are types of dental treatment used to restore cavities without using the new total prosthesis. These treatments help to preserve more natural teeth as they fit in the remaining part of the tooth like a piece of the jigsaw puzzle. 

 While Inlay, Onlay, and Overlay, these small dentures are manufactured like a complete denture (using cad/cam, milling, and staining), the dental filling is treated by filling directly dental material (amalgam, composite resin) into the cavities. These dental treatments are used mainly for posterior teeth to improve chewing and prevent further decay

 1. Dental filling

 A dental filling is a procedure used to fill a hole in a tooth to prevent further tooth decay. A filling is usually a simple and early treatment for tooth decay. However, it may be broken and allow leftovers trapped between the tooth and the filling. Thus, a regular dental check-up is necessary. The materials that are usually used for this treatment recently are amalgam and composite resin.

• Amalgam: a mixture of metals, including silver, copper, tin, mercury, and zinc. Although exposure to mercury can be toxic, amalgam is safe and effective to use for most people  

• Composite resin: Composite resin is a white tooth-colored material, so it matches the color of the other teeth and looks more natural than amalgam.

Dental Filling

  2. Inlay

 When the tooth decay area is too bigger for a general dental filling, an inlay will be considered an alternative method. Inlays usually cover the central part of the tooth or the area between the cusps and are positioned within the hard tissues of the tooth. They do not cover the cusps. For this reason, they are shaped to fit perfectly on your teeth, so can prevent leftovers from entering underneath tooth decay areas, creating further decay.  The material used for inlays usually is porcelain likes other dental crowns, so it will be stronger and more durable compares with other composite fillings.


  3. Onlay

 When a patient gets a decay of the middle and side of your tooth, an Onlay can be considered a treating method as it may cover one or more cusps of your tooth. Compared with inlay, Onlay covers more areas, they are positioned inside the deep tissues of the tooth as well as cover part of the biting surface of the tooth. This helps to protect the damaged tooth from a direct chewing load.


 4. Overlay

Overlays cover a much larger portion of the occlusal or biting surface. Though they are often compared to partial crowns, overlays are very different from crowns. The main difference is overlays keep more of the natural tooth structure intact.


  5. What is the difference between Inlays, Onlays, and Overlays?

 The main difference among inlays, Onlays, and overlays is in the size of the area of the tooth being treated. Inlays cover the central part of the tooth, they do not cover the cusps while Onlays cover a larger area. Besides replacing the internal part of the damaged tooth, they also cover one of the cusps. So, they are positioned inside the deep tissues of the tooth as well as cover part of the biting surface of the tooth. This helps to protect the damaged tooth from direct chewing.

In cases where there is a large area between the cusps that are being covered by inlays, there are chances that it may force the cusps apart under chewing pressure. This increases the risk of tooth fracture in the future. Onlays or overlays which spread chewing pressure uniformly and also cover one or more cusps reduce the possibility of fractures.

6. Procedure

The manufacturing process of Inlay, Onlay, and Overlay teeth is similar to the manufacturing process of a complete denture, these teeth are also designed on cad/cam to ensure a snug fit, using ceramic materials such as Zirconia, Emax upon request and stained to resemble natural teeth. At Xdent dental outsourcing, we commit to creating durable inlays, Onlays, and overlays that give our customers confidence.


Onlay at Xdent


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