Dental Injuries

Most hospitals have on-staff oral surgeons who can perform emergency tooth removal

Dental injuries include trauma to the face or teeth, wear and tear, and broken and chipped teeth. There are many types of dental injuries, but the most common include the following:

• A minor tooth fracture usually involves chipping of the enamel only.
• A deeper fracture can involve both the enamel and the dentin of a tooth.
• A serious fracture that exposes both the dentin and the pulp tissue should be treated promptly.

Common causes of dental injuries include trauma to the face or teeth, which can be caused by the following:

• Auto accidents
• Falls
• Injury from a variety of sports, such as:
  • Football
  • Hockey
  • Soccer
  • Volleyball
  • Basketball
  • Baseball

Wear and tear due to cavities and chewing or biting down on hard objects, such as pencils, ice cubes, nuts, and hard candies, can also lead to tooth fractures.

The only symptom of minor tooth chipping may be sharp or rough tooth edges that irritate the cheek and tongue. The injured tooth itself may not be painful or sensitive to food or temperature.

Patients suffering significant head, neck, or facial trauma should be evaluated and treated in a hospital emergency room setting. Such trauma may involve the following:

• Bleeding from the nose or ears
• Concussion
• Dizziness
• Lapse of memory
• Disorientation
• Severe headache
• Earache
• Breaking (fracture) of the skull and/or jaws

Dental injury without associated head and neck trauma can usually be evaluated and treated in a dental office. Such dental injuries include broken teeth (fractured teeth), teeth knocked out of the mouth, or teeth displaced by unexpected external forces. These dental injuries include swelling of the gum and oral tissue.

Most hospitals have on-staff oral surgeons who can treat fractures of the upper or lower jaw and perform emergency tooth removal (dental extractions) and reconstruction of the dental arches.

Different tests are performed in the mouth to determine if a tooth fracture is present. In some instances, dental X-rays can help to diagnose, locate, and measure the extent of tooth fractures.

Instead of being completely knocked out of the mouth, a tooth can be displaced into another position. In the mouth, a displaced tooth may be pulled out and appear elongated, or be pushed in and appear shorter. A displaced tooth can also be pushed forward, backward, sideways, or rotated.

The sooner the dentist can splint or realign the tooth with orthodontic brackets and wires, the easier it can be brought back into proper alignment.

Trauma significant enough to cause tooth displacement can also lead to pulp injury. As a result, a displaced tooth should be evaluated periodically for several months to determine if a root canal procedure or tooth extraction is needed.

A minor tooth fracture usually involves chipping of the enamel only. The tooth is not displaced out of its position and there is no bleeding from the gums. The risk of pulp injury is low and treatment is usually not considered urgent. A small amount of orthodontic wax or sugarless gum can be placed over the rough edge until the dentist can be seen. Depending on the amount of enamel lost, definitive treatment usually involves placing a dental filling or a crown to restore the tooth to normal contour.

A deeper fracture can involve both the enamel and the dentin of a tooth. Even though a deep fracture is present, the tooth may not be displaced or out of position and the gums may not be bleeding. These deeper fractures may be sensitive to changes in temperature, chewing, or biting.

Prolonged exposure to dentin leaves the tooth vulnerable to decay which can advance rapidly. Therefore, fractures involving the dentin are treated promptly. Treatment involves placing a dental filling or a crown. Unless there are continuing symptoms of pain, the tooth can be monitored with routine dental X-rays to ensure that the tooth is healthy.

If a fracture has significantly injured the pulp, then treatment involves either extraction of the tooth or root canal treatment. Extraction is indicated if the tooth has been significantly weakened by the fracture and its form and function cannot be properly restored.

If the tooth's form and function can be restored, root canal treatment is performed to prevent infection. This procedure involves removing all the dying pulp tissue and replacing it with an inert material to keep infection out. Once the root canal treatment is complete, the tooth can be restored with a filling or crown.

Tooth fractures can range from minor (involving chipping of the outer tooth layers called enamel and dentin) to severe (involving vertical, diagonal, or horizontal fractures of the tooth and/or root).

Enamel and dentin are the two outer protective layers of the tooth. The enamel is the outermost white hard surface. The dentin is a yellow layer lying just beneath the enamel. Enamel and dentin both serve to protect the inner living tooth tissue called the pulp. The portion of the tooth that is visible in the mouth is called the crown and is only a part of the entire tooth structure. The remaining portion of the tooth is buried in the bone and is called the root.

Serious Tooth Fracture Treatment

A serious fracture exposes both the dentin and the pulp tissue and should be treated promptly. Serious fractures may make the tooth displaced and loose, and cause the gums to bleed. To prevent the loose tooth from falling out completely, the dentist can splint the loose tooth by bonding it to the adjacent teeth to help stabilize it while the underlying bone and gums heal.

Because of the high risk of pulp infection after exposure of the pulp to the oral environment, a root canal procedure may need to be performed during the first visit. Alternatively, the dentist may elect to only apply a sedative dressing on the splinted tooth to help calm the tooth pain. The tooth will then be reevaluated in two to four weeks to determine if a root canal procedure is necessary. If the tooth appears to have recovered and is stable in the mouth, the splint is removed at that time and a filling or crown is placed to restore the fractured tooth. The tooth may still require periodic monitoring over time (months to a year) to determine if any further treatment will be needed.

The most serious injuries involve vertical, diagonal, or horizontal fractures of the tooth roots. In most instances, a fracture of the tooth root leaves the injured tooth very loose and unable to be restored with dental work, thus necessitating tooth extraction. The extracted tooth is often replaced with a removable plate containing a false tooth as a temporary measure until a more definite plan for tooth replacement is made.

There are some specific instances where teeth with horizontal fractures near the tip of the root may not need extraction. Root canal treatment for the injured tooth may be required in the future if symptoms of pulp death and tooth infection appear. Periodic dental X-rays of the fractured tooth are performed to monitor it closely.

The upper front permanent teeth are the most common teeth to be completely knocked out ("avulsed"). Primary (baby) teeth that are knocked out from injury are usually not reimplanted into the mouth since they will be replaced naturally by permanent teeth later.

In the event of having a permanent tooth knocked out, care should be taken to handle the tooth only by its crown (chewing surface) and not by its root, gently rinsed in clean water or milk and placed back (reimplanted) into the socket from where it came. This can be done by the patient or parent and then checked by the dentist. If the parent or patient is unsure about reimplanting the tooth, then the tooth should be stored in milk or an emergency tooth preservation solution and brought to the dentist as soon as possible. Alternatively, in older children and adults who are calm, the tooth may be held within the cheeks inside of the mouth while traveling to the dental office. Unfortunately, water is not considered a good storage medium for a tooth for long periods.

The most important variable affecting the success of reimplantation is the amount of time that the tooth is out of its socket. Teeth reimplanted within one hour of the accident frequently reattach to their teeth sockets. After reimplanting the tooth into its original socket, the dentist can then splint this tooth into adjacent teeth for two to eight weeks. Splinting helps to stabilize the tooth while the bone and tissue around it heal. During the splinting period, the patient should eat soft foods, avoid biting on the splinted teeth, and brush all the other teeth diligently to keep the mouth as clean as possible. In adults, the reimplanted tooth should have a root canal procedure within seven to 10 days.

Reimplanted permanent teeth in children (where the tooth root has not yet completely formed) may not need a root canal procedure. These teeth should be observed for at least five years for signs and symptoms such as pain, discoloration, gum abscess, or abscess visible on a dental X-ray, which could indicate a dying pulp.

In most patients who have had tooth reimplantation, over-the-counter medications like acetaminophen (Tylenol) or ibuprofen (Advil) are sufficient for pain relief. Since the splinted teeth cannot be brushed normally and the splint usually collects extra dental plaque and food debris, chlorhexidine gluconate (Peridex) mouth rinse may be prescribed to prevent and control gum inflammation (gingivitis). Oral antibiotics and a tetanus toxoid injection are considered for patients with accompanying significant soft-tissue cuts (lacerations).

The most important variable affecting the success of reimplantation of a tooth that is knocked out is the amount of time that the tooth is out of its socket. Care should be taken to handle the knocked-out tooth only by its crown and not by its root.

Death of pulp tissue can lead to a serious tooth infection and abscess.

Prevention of dental injuries involves aligning protruding front teeth with dental braces and using face masks and mouthguards while participating in sports. Mouthguards have been shown to reduce trauma not only to teeth, gums, and the surrounding jaw bone but also to the temporomandibular joints (TMJ). Mouthguards can also reduce the intensity and number of head concussions, as well as reduce pressure and bone deformation of the skull when a force is directed at the chin. Before the mandatory use of face masks and mouthguards for high school and college football players in 1963, 50% of all football injuries involved the face and the mouth.

Since the mandatory use of these protective devices, dental injuries in football players have almost been eliminated. It is now recommended or required that a mouthguard be worn for the following sports:

• Football
• Baseball
• Basketball
• Racquetball
• Soccer
• Ice hockey
• Field hockey
• Street hockey
• Wrestling
• Boxing
• Martial arts
• Volleyball
• Rollerblading
• Skating
• Skateboarding
• Bicycling

Mouthguards can be purchased in pharmacies and sports supply stores and molded at home. They can also be custom-made by the dentist.

• Store-bought mouthguards are usually less expensive than custom-made ones. However, store-bought mouthguards may not fit the athlete's mouth well, become loose, be uncomfortably bulky, and may interfere with speech or breathing.
• The ideal mouthguards are custom-made by a dentist using a mold taken of the athlete's upper dental arch.
• The custom mouthguard is then fabricated in a lab out of a special plastic that conforms comfortably around the teeth and gums.
• A well-fitting custom mouthguard should be comfortable and not interfere with breathing and speech.