The inlay as a restoration for a destroyed tooth

Introduction

An inlay belongs to the group of so-called rigid filling materials and has to be made in the dental laboratory on the basis of an impression. As an alternative, plastic materials are also used in caries therapy, which are inserted into the tooth in a deformable state and only hardened afterwards. An inlay tooth represents a workpiece adapted to the specific cavity structure of the individual patient.

The production in the dental laboratory is relatively complex and must be carried out with the utmost care so that the inlay can be inserted into the tooth and glued in place with an exact fit. Therefore, exact models of the situation in the patient’s mouth are necessary. This is obtained by taking a precision impression.

Basically, such inlays can be made of different materials, which are often found: Similar to plastic tooth fillings, inlays are divided into different classes according to their size. An inlay filling can cover one to five tooth surfaces, but can only replicate the occlusal surfaces of a tooth. In cases where one or two tooth cusps also need to be replaced, so-called onlays (dome filling) are used instead of inlays.

In principle, an onlay is only a slightly larger inlay filling. To reproduce all cusps of a tooth, an overlay is usually made which can replace the entire occlusal surface.

  • Gold
  • Ceramics
  • Plastics or
  • Titanium application.

The production of a gold inlay is a great challenge from both a dental and a dental technical point of view, because the reproduction of the natural shape of the tooth is not easy with this material and requires the highest precision.

Before the inlay can be made, the carious defect must be completely removed from the tooth substance. The tooth is reamed under local anesthesia (local anesthesia). After the caries is removed, the dentist must also remove part of the healthy tooth substance and form a box-shaped cavity (box preparation).

Then an impression of the tooth is made and plaster is poured in the dental laboratory. Based on the resulting plaster model, the gold inlay can first be formed from wax. This wax model is then placed in a casting mold and melted down.

This procedure creates a cavity within the casting mold which reflects the exact shape of the tooth cavity and, after filling with a liquid gold alloy, produces the inlay filling. Afterwards the inlay only needs to be refined and polished. In the dental office the inlay filling can be bonded to the tooth with a special luting cement or plastic. If the bite height (occlusion) is checked and it turns out that the inlay is too high in some areas and thus hinders the natural closure of the jaw, these areas can be ground in afterwards. Gold inlays have the advantage of being particularly durable, but are very expensive due to the complex manufacturing process.