A temporary crown is a protective cap placed over a tooth that has been prepared for a permanent restoration. This provisional covering shields the sensitive tooth structure and prevents surrounding teeth from shifting. It is secured with temporary dental cement, which is deliberately designed to have a weak bond for easy removal. Using a straw is possible, but the suction it creates poses a significant risk of dislodgement.
The Risk of Negative Pressure and Suction
The risk associated with using a straw stems from the physics of suction, which creates a negative pressure gradient within the mouth. This pressure differential acts directly on the interface between the temporary crown and the prepared tooth surface. Since the temporary cement is formulated for easy removal, its adhesive strength is intentionally low.
The negative pressure can compromise the bond of this non-permanent cement, effectively breaking the seal and pulling the crown off the prepared tooth. This risk is not limited only to straws; any activity that generates strong suction or sudden pressure changes should be avoided. This includes smoking, vaping, or forcefully spitting liquids from the mouth, as these actions mimic the same mechanical force that can dislodge the provisional restoration. The loss of the temporary crown exposes the underlying tooth to mechanical stress, bacteria, and temperature sensitivity, necessitating an immediate visit to the dentist.
Protecting the Temporary Crown Through Diet and Chewing
Protecting the temporary crown requires careful management of mechanical and thermal stresses during eating. It is important to chew food primarily on the opposite side of the mouth to minimize direct force. The temporary crown material is not as durable as the final restoration and can fracture under excessive biting pressure.
Certain types of foods must be avoided because they risk pulling the crown off or cracking the material. Sticky items like chewing gum, caramels, and taffy can adhere strongly to the crown, pulling the restoration free when the mouth is opened. Hard or crunchy foods, such as nuts, ice, hard candies, and tough vegetables, can directly chip or fracture the temporary material.
The prepared tooth underneath the crown often has exposed dentin, making it highly susceptible to thermal sensitivity. Consuming liquids or foods that are extremely hot or excessively cold can cause sharp, uncomfortable pain. Avoiding these temperature extremes helps maintain comfort and prevents micro-expansion or contraction that could weaken the temporary cement seal.
What to Do If the Temporary Crown Comes Loose
If the temporary crown becomes loose or falls off, remain calm and locate the crown. Once retrieved, gently clean the inside of the crown and the underlying prepared tooth with warm water to remove debris. The priority is to contact the dental office immediately to schedule an appointment for re-cementation, as the exposed tooth is vulnerable to damage and sensitivity.
If the crown is intact, a temporary re-seating may be attempted to protect the tooth until the dental visit. Over-the-counter dental cement kits are available at most pharmacies for this purpose. Alternatively, a small amount of denture adhesive, petroleum jelly, or toothpaste can be used as an emergency measure to hold the crown in place.
Apply a small amount of the chosen material inside the crown, place it back over the tooth, and gently bite down to secure its position. This is only a stopgap measure and not a permanent fix. Under no circumstances should household glues or strong adhesives be used, as they can damage the tooth and prevent the dentist from properly removing the crown later.