Yes, it is often possible to receive orthodontic treatment with braces even if you have “silver caps,” formally known as stainless steel crowns (SSCs). The presence of these metal restorations does not automatically prevent the straightening of teeth, but it does require specialized techniques and careful planning from the orthodontist. The primary challenge is ensuring the bracket adheres securely to the smooth metal surface of the crown, which differs significantly from bonding to natural tooth enamel. Orthodontic treatment involves a coordinated approach to address the unique material properties of the crown while applying the forces necessary for tooth movement.
Understanding Stainless Steel Crowns
Stainless steel crowns are prefabricated metal caps used primarily in pediatric dentistry to restore and protect severely decayed, damaged, or fractured primary (baby) teeth. These crowns are composed of a durable mixture of stainless steel, nickel, and chromium, offering full coverage protection when a standard filling is not sufficient to maintain the tooth’s structure. They are often recommended after a pulpal therapy, commonly known as a baby root canal, or when a child’s cooperation for a complex filling procedure is limited.
The metallic composition and pre-formed nature of the crown allow it to withstand the strong forces of chewing until the underlying primary tooth naturally exfoliates. By covering the entire tooth, the SSC prevents further decay and helps maintain the necessary space in the dental arch for the permanent tooth to erupt correctly. Because these crowns are meant to last for years, they may still be present when a patient begins orthodontic treatment.
Specialized Techniques for Bracket Attachment
Attaching an orthodontic bracket to a stainless steel crown is more complex than bonding to natural tooth enamel, as the metal surface cannot be prepared using traditional acid etching techniques. Acid etching creates microscopic pores on the enamel surface, which allow the bonding adhesive to mechanically lock onto the tooth. This process is ineffective on the smooth, non-porous metal of a stainless steel crown.
To create a strong and reliable bond on the metal surface, orthodontists must instead rely on a combination of mechanical and chemical retention methods. One technique involves roughening the crown surface through micro-etching, often performed using an aluminum oxide air-abrasion unit, or by gently abrading the surface with a diamond bur. This mechanical roughening creates a textured surface that increases the overall surface area for the adhesive to grip.
Once the metal surface is prepared, a specialized metal primer is typically applied before the composite resin adhesive is used to bond the bracket. The metal primer contains chemicals that promote a stronger chemical bond between the metal and the composite resin, enhancing the shear bond strength. Studies have shown that these combined techniques—such as aluminablasting followed by a metal primer and a specific adhesive resin—can achieve bond strength values needed to withstand orthodontic forces. The goal is to ensure the bracket remains firmly attached throughout the treatment duration without causing the crown to fail.
Coordination of Care and Post-Treatment Replacement
Successfully treating a patient with stainless steel crowns requires close collaboration between the orthodontist and the pediatric or general dentist. Before starting treatment, the general condition and stability of the SSCs must be evaluated to ensure they can withstand the forces and duration of the orthodontic process. Monitoring is continuous throughout the treatment, as any loosening or failure of the crown can disrupt the alignment process. In some cases, it may be necessary to place a traditional orthodontic band around the crown for greater stability, especially on teeth subjected to heavy forces.
The most significant long-term consideration is the fate of the stainless steel crown once the teeth are straight. Since SSCs are temporary restorations, they are usually removed and replaced after orthodontic treatment is complete. If the SSC is on a primary tooth that is still far from its natural exfoliation time, the pediatric dentist may replace it with a new, permanent restoration, such as a tooth-colored filling or a more aesthetic crown. The overall treatment plan should account for this replacement phase to ensure a seamless transition to the final, healthy smile.