A dental crown is a tooth-shaped cap placed over a damaged tooth to restore its shape, size, strength, and appearance. A sonic toothbrush uses high-frequency, side-to-side vibrations to clean the teeth. The primary concern is whether the intense movement of a sonic toothbrush can damage the crown material or loosen the cement holding it in place. Sonic toothbrushes are generally safe for permanent crowns, provided the user employs the correct, gentle technique. This technology can be more effective than a manual brush at cleaning the area where the crown meets the gum line.
How Sonic Toothbrushes Clean
Sonic toothbrushes operate using two distinct cleaning actions. The mechanical scrubbing action involves the high-speed sweeping motion of the bristles, which can reach up to 62,000 strokes per minute. This rapid movement effectively dislodges plaque and debris from the tooth surfaces with minimal physical effort.
The second cleaning component is the fluid dynamics created by the intense vibrations. These high-frequency movements agitate the mixture of saliva, water, and toothpaste, generating pressure waves. This cleaning wave is propelled beyond the physical reach of the bristles, allowing it to clean areas like between teeth and slightly below the gum line.
This non-contact cleaning action makes sonic brushes gentle on dental work. The cleaning power comes from frequency and fluid movement, not abrasive force or heavy scrubbing, which is the main source of potential damage from manual brushing. Since the vibrations are not strong enough to compromise the crown material or the bonding agent, the technology is highly compatible with permanent dental restorations.
Crown Materials and Sonic Safety
Modern dental crowns are engineered from extremely durable materials designed to withstand significant biting and chewing forces. Common materials include porcelain, ceramic, metal alloys, and porcelain-fused-to-metal, all of which are highly compatible with sonic cleaning technology. The high-frequency vibrations do not affect the structural integrity of these restorative materials.
A common concern is the margin, the seal where the crown meets the natural tooth surface, secured by dental cement. Studies show that brushing for the equivalent of two years with a sonic toothbrush results in no significant difference in the tensile force required to remove cemented crowns. This evidence confirms that the sonic action does not compromise the bonding agent used to secure the restoration.
For composite resin crowns, which are less durable and more prone to staining or wear, the sonic toothbrush is still safe. The soft bristles and non-abrasive action are protective. Using a non-abrasive toothpaste is recommended to maintain the crown’s surface polish while efficiently cleaning the surrounding area.
Proper Brushing Technique Around Crowns
While sonic toothbrushes are safe, proper technique is necessary to maximize benefits and ensure the crown’s longevity. Users should select a brush head with soft bristles, as firm bristles can irritate the gums or scratch the crown’s surface. Since the sonic device is designed to do the work, the user should apply minimal pressure.
A light touch is sufficient for effective plaque removal; pressing too hard prevents the bristles from properly sweeping away debris. The brush head should be gently guided from tooth to tooth, allowing the sonic vibrations to clean each surface for a few seconds. When cleaning a crowned tooth, focus the brush head at a 45-degree angle toward the gum line to clean the crown margin.
Temporary Crowns
Special attention must be given to temporary crowns, which are secured with a much weaker adhesive. The high vibrations of a sonic toothbrush could potentially loosen a temporary crown. It is advisable to use a manual, soft-bristled toothbrush in that area until the permanent crown is placed. Once the permanent crown is securely cemented, the sonic toothbrush can be safely resumed.