Both overlay inlaid, inlay and partial crowns are utilized when there are cavities in a tooth to be cleaned or restored, and for being too large, cannot be covered with white fillings.
The overlay inlays are used when decay or fracture incorporate areas of a tooth that make amalgam or composite restorations essentially inadequate. Examples of these cases may be a cusp fracture or if the remaining tooth structure undermines perimeter walls of a tooth, then a scale overlay would be indicated. As is the case with inlay, an overlay is an indirect restoration which incorporates a cusp or cusps covering or place missing vertices. All the benefits of an inlay are present in the onlay restoration.
The overlay allows to preserve the tooth structure when the only other alternative is to totally eliminate cusps and perimeter walls for restoration with a crown. Just as inlays, the overlay are made outside the mouth and are usually made of gold or porcelain. Gold restorations have been performed for many years and have an excellent track record. In recent years, new types of porcelains which have developed longevity appear to compete with gold. Either way, both inlaid inlay and overlay are made in a dental laboratory, and made restoration is custom made for each patient. During a second visit to the dentist, the final prosthesis is delivered.
The overlay can be inlaid porcelain, gold, or composite resin. These parts are attached to the damaged area of the tooth. An inlay (which is similar to a filler) is used inside the tips of the cusps of the teeth. Aoveray is a substantial reconstruction, but which extends along one or more of the cusps of the teeth.
Difference between overlay inlaid, inlay and onlays
Inlays are used if decay or fracture is so extensive that a direct restoration, such as amalgam or composite, would compromise the structural integrity of the restored tooth by the opportunity to be undermining the remaining tooth structure or providing the opposition with normal forces of occlusal (biting). In such situations, it may be indicated indirect inlay gold inlay or porcelain. When an inlay is used, the margin of tooth that is left can be almost zero and polished leaving a very thin layer of contact line, where the appearance of recurrent decay will be almost impossible. It is for this reason that some dentists recommend inlays as the ideal situation for almost any filling restoration.
There is a great superiority of the inlay as restoration tale as in terms of resistance to the occlusal forces, protection against recurrent caries, the accuracy of manufacture, the marginal integrity, proper contour to the gingival health, easy cleaning and many other aspects of quality options that make it an excellent alternative to the direct restoration. For this reason, some patients request inlay restorations in order to benefit from its wide range of advantages even when an amalgam or composite would be sufficient for your problem.
Partial crown restorations are among one overlay and a full crown with respect to the preservation of natural tooth structure. In the past, it was somewhat common to find dentists who prepared teeth for 3/4 and 7/8 crowns (partial crowns). These restorations are generally manufactured for the second premolars or first molars, which could only be slightly visible when the patient smiles. Therefore, the dentist can preserve healthy natural tooth structure that exists in the mesiobuccal corner tooth for cosmetic purposes, the remainder of the tooth and can surround and cover restoration material.
Implementation of the overlay scale
The overlay inlaid require two appointments to complete the procedure. During the first visit, the filling to be replaced or the damaged or decaying area of the tooth is removed the tooth preparation for overlay embedding. To ensure proper fit and bite, an impression of the tooth is created and sent to the laboratory for fabrication of overlay. Dentist at this first visit to apply a temporary sealant on the tooth and is asked to schedule a second visit.
On the second visit, the dentist will remove the temporary sealant. The dentist will make sure that the inlay overlay fits properly. If the fit is satisfactory, the overlay is bonded to the tooth with a strong resin and polished then getting a smooth finish.
Considerations
Traditional fillings can reduce the strength of a natural tooth by up to 50%. Alternatively, the inlay and overlay are directly bonded to the tooth using special high-strength resins, which even today can increase the strength of a tooth by up to 75%. As a result, they can last from 10 to 30 years. In some cases, where the damage to the tooth is not wide enough to place a crown, inlay can provide a very good alternative.