A composite onlay is an indirect dental restoration made of tooth-colored composite resin. It repairs moderate-to-severe tooth structure loss (e.g., from decay, fractures) that's too large for direct fillings but doesn't need a full crown. Unlike fillings placed directly in the mouth, onlays are crafted in a lab, then bonded to the tooth.
Core Advantages
Aesthetics: Matches natural tooth shade and translucency, ideal for visible teeth (anterior/posterior).
Tooth Preservation: Requires less enamel/dentin removal than crowns, preserving healthy tooth structure.
Strong Bonding: Bonds tightly to tooth surfaces via adhesive, reducing microleakage (a cause of secondary decay).
Typical Fabrication Process
First Visit: The dentist removes decay, shapes the tooth for onlay placement, and takes an impression (digital or physical) of the tooth.
Lab Fabrication: Technicians use the impression to make the composite onlay, ensuring it fits the tooth's anatomy.
Second Visit: The dentist checks the onlay's fit/color, etches the tooth surface, applies bonding agent, and cements the onlay permanently.
Maintenance Tips
Clean with regular brushing, flossing, and interdental tools to avoid plaque buildup at the onlay-tooth junction.
Avoid biting hard objects (e.g., ice, nutshells) to prevent onlay chipping or dislodgment.
Schedule annual dental checks to assess the onlay's condition and bonding integrity.