Advantages of direct composite over indirect aesthetic restoration include:
Minimal preparation—While most indirect restorations require preparation of the tooth to develop "draw" and eliminate undercuts, direct restorations can be built into undercuts and around corners, often requiring less preparation. Indirect restorations need a certain thickness for strength and then need to be cemented or bonded in to place. Directly applied composite resin can be made to be "paper thin" in areas.
Lower fee to the patient—Fees can often be lower for direct than for indirect procedures because of the time savings (no second appointment or laboratory charges).
Easily removed—When it is necessary or desirable to remove composite resin from the tooth, it can be accomplished by using a carbide-finishing bur in a high-speed handpiece without damaging the underlying natural tooth structure.
Easily repaired—When it is necessary to repair a fracture or chip, composite resin can be roughened by microabrasion (or with a diamond bur) and treated with phosphoric acid to clean the abraded surfaces. Then, a bonding agent can be applied and new composite resin can be added and light-cured. Once the new material has been finished and polished, the repair is often imperceptible and long-lasting
