Essential Tips for Treating Active Patients

Kenneth A. Honsik, MD

Practice Essentials Series Editors:
Kimberly G. Harmon, MD; Aaron Rubin, MD

THE PHYSICIAN AND SPORTSMEDICINE - VOL 32 - NO. 9 - SEPTEMBER 2004

In Brief: Dentoalveolar trauma in sports is common. One third of dental injuries in the United States occur in sports-related activities, so team physicians should be able to recognize and properly treat dental injuries on the field. Tooth fracture, luxation, avulsion, and socket injury are the main types of dentoalveolar trauma. In many cases, other maxillofacial trauma can be associated with dental injuries, so physicians who examine these patients should be aware of additional associated injuries. Tooth injury is often preventable with the appropriate use of properly fitted mouth guards. Physicians should be familiar with different types and be able to suggest the correct mouth guard for a given activity.

Dental injuries on the athletic field are common and can have serious negative consequences for an athlete. Prevention is the key, but proper immediate treatment is essential. Most athletes have some basic medical insurance; however, not all athletes have dental insurance. Costs for improperly treated dental injuries can be sizable and can also have much higher complication rates and poor cosmetic results. On-field sports medicine providers can diminish poor outcomes through appropriate initial treatment and educate athletes, parents, and coaches about proper prevention.

The Centers for Disease Control and Prevention (CDC) in 2001 estimated that approximately one third of all dental injuries in the United States are sports related.¹ Studies from other countries provide valuable statistics on frequency and type of dental injury. For example, one large study² examined maxillofacial trauma in patients registered in the Department of Maxillofacial Surgery at the University of Innsbruck, Austria, from 1991 and 2000. Of the 9,543 patients seen during that time for maxillofacial trauma, 2,991 (31%) of those injuries were sports related. Dentoalveolar trauma occurred in 51% of all maxillofacial trauma, and 56% of the dentoalveolar injuries were complicated by associated injuries.² Such data are useful in predicting the prevalence of dental trauma in collision or contact sports, such as skiing, soccer, cycling, mountain biking, ice hockey, and ball sports, among many others.

Basic Dental Anatomy

Teeth are housed within maxillary and mandibular alveolar bone (figure 1), which contains individual sockets for each tooth. Each tooth consists of a root and crown. The root attaches to the socket via periodontal ligaments and is covered by cementum. The root houses the vascular pulp, which furnishes the blood and nerve supply for the tooth. The crown is made up of a tough outer shell of enamel that protects an inner layer of dentin and the portion of the pulp that extends into crown. The border at which the crown meets the root is known as the cementoenamel junction.³ The gingival tissue overlies the mandible and maxilla and seals the tooth in the socket.

Common Dental Injuries

Dental injuries include fractures, luxation, avulsion, socket fracture, and associated trauma (eg, lip and mucosal lacerations, maxillary or mandibular fractures, temporomandibular joint damage, and concussion). Physicians must recognize each injury type to provide proper initial treatment and refer more seriously injured patients to the emergency department, team dentist, or other dental professional.

Fractures. Tooth fractures disrupt the enamel or cementum and may involve dentin or pulp. They are typically caused by a direct blow to the tooth or by an indirect blow transmitted through the jaw.⁴ Fractures can affect the root, crown, or both, producing a wide range of severity. Fractures can be as simple as a chipped tooth, which only involves the enamel, as well as the other extreme, a vertical fracture, which cleaves the tooth from the crown through the root, involving enamel, dentin, and pulp along the fissure. When the pulp is involved, the injury is usually very painful and is frequently identified as a bleeding site or a pinkish dot in the center of the dentin (figure 2).^3,5,6 Treatment and return to play varies with the severity of the fracture.

Crown fractures are commonly classified into one of four types (figure 3):

• Type 1 is an enamel only or "chip fracture";
• Type 2 is a fracture through enamel and dentin;
• Type 3 involves the enamel, dentin, and pulp; and
• Type 4 fractures involve the root.

The closer a root fracture is to the cementoenamel junction, the more unstable it is and the poorer the prognosis.³ Dental injuries that involve the root and pulp are considered more severe and require immediate professional attention.

Luxation. Luxation is the displacement of the tooth from its normal position (figure 4). Teeth may become laterally luxated, extruded, or intruded. A laterally luxated tooth will be displaced anterior or posterior to the adjacent teeth. If the tooth is extruded, it will appear longer than the other teeth in the arch (partial avulsion). In cases of intrusion, the tooth will be shorter than its neighboring row and should not be repositioned on site. Intrusion typically involves disruption of the alveolar socket and periodontal ligaments.^3,6 Loose teeth are considered tooth subluxations without significant displacement or alveolar bone disruption. However, in some cases, a "loose tooth" may be the result of a transverse root or cementoenamel junction fracture. Radiographs are recommended for all trauma-induced loose teeth.

Avulsion. Tooth avulsion is a total separation of the tooth from the socket (figure 5). This injury involves complete rupture of the periodontal ligaments. As such, the time from injury to reimplantation of the tooth is critical to its survival. Vitality of the periodontal ligament (PDL) cells on the root surface of an avulsed tooth will determine whether the PDL will regenerate or if the root will ankylose to the bone. If ankylosis occurs, the root of the tooth will ultimately be replaced by bone and the tooth will be lost.

The need for endodontic (root canal) therapy following the proper reimplantation of an avulsed tooth is determined by the maturity of the root at the time of injury. A mature root has a closed apex, and this makes revascularization of the dental pulp impossible and always requires endodontic therapy. An immature root has an open apex and allows for a chance of revascularization following reimplantation, possibly avoiding endodontic therapy. Only permanent teeth should be reimplanted. Primary or "baby teeth" should never be reimplanted.^3,7,8

Associated injuries. All of the previously described injuries can be associated with other types of maxillofacial trauma. In the previously noted study² from Austria, 56% of dentoalveolar injuries were complicated by other injuries. Associated maxillofacial injuries can be as simple as a gum or lip laceration to as serious as a concussion, temporomandibular joint damage, or facial or alveolar bone fracture. The examiner should always look for these injuries when evaluating an active patient for dentoalveolar trauma. Lip or mouth lacerations should be radiographed before closure to rule out embedded tooth or bone fragments when these injuries are associated with a tooth fracture.³

Patient Examination

Because of the high velocity forces involved in dentoalveolar trauma, the provider should always begin the exam with the ABCs of trauma (airway, breathing, circulation, and consciousness/alertness). It is extremely important to determine alertness because of increased risk of tooth fragment aspiration in concussed or unconscious athlete. Using a light source, physicians should visually inspect the entire mouth and maxillofacial region. The athlete's mouth may need to be rinsed for proper inspection. When doing this, use clean water for rinsing, and do not discard the rinse immediately to allow inspection for tooth fragments or teeth before disposal! If a fracture or avulsion is seen on examination and the fragment or missing tooth is not visible within the mouth, the athlete's clothes and site of injury should be searched immediately.

After completing the visual inspection, the provider should then palpate all teeth in both arches with a sterile, gloved hand, checking for asymmetry, looseness, or mandibular and maxillary deformities. Examination procedures, treatment recommendations, and return-to-play guidelines depend on the type of injury incurred ( table 1).^3-6,8,9

Preventing Dentoalveolar Injury

The American Dental Association recommends use of mouth guards for participation in football, gymnastics, basketball, boxing, field hockey, handball, ice hockey, lacrosse, skateboarding, skiing, skydiving, soccer, martial arts, racquetball, squash, roller hockey, rugby, volleyball, water polo, weightlifting, and wrestling. Mouth guard use has been shown to decrease the frequency and severity of dental injuries.¹⁰

Currently, three types of mouth guards are available to athletes: stock, mouth-formed ("boil-and-bite"), and custom-fabricated (figure 6; also see the Patient Adviser, "Steps to Take for Dental Injuries"). The stock mouth guard comes in set sizes and is the least protective type. They are commonly trimmed down by the athletes for comfort and held in place by the bite force of the athlete. Boil-and-bite mouth guards are the most commonly worn and marketed types but provide only mediocre protection. The boil-and-bite mouth guard loses much of its protective properties during the form-fitting process. An overall thickness of 3 mm is required for adequate cushion and absorption. Many times the athlete will bite too far through the mouth guard during the forming process, reducing the cushion between the teeth. Also throughout the season, athletes will chew through portions of the mouth guard, further reducing the cushion and rendering it ineffective.¹¹ Custom mouth guards are recommended by sports physicians and dental professionals. They are significantly more expensive than over-the-counter types but have been proven to provide superior protection.^11,12

Custom mouth guards are made by a dentist for an exact fit and are fashioned from a mold or cast of the patient's mouth. Custom mouth guards may be produced by either a vacuum or pressure-lamination process. The pressure laminate variety is felt to be slightly superior to the vacuum form, because the multiple layers ensure adequate thickness of the device. These mouth guards may also be further customized by making them in the school or team colors (figure 6D). Much discussion has centered on the question of whether mouth guards aid in preventing concussions. To date, there is no evidence that mouth guard use decreases the incidence of concussion among athletes.^10,13

Putting the Bite on Dental Injury

Dental injuries are very common in most contact and collision sports. Sports medicine providers should be familiar and comfortable with basic diagnosis and emergency care for dental injuries. Care for more serious injuries should be supplied by team dentists or other dental providers. If treated correctly on the field, injured patients can avoid complications such as poor cosmesis, infection, and extensive dental reconstruction. Use of a properly fitted mouth guard is effective in preventing dental injury, with custom types providing the best protection.^10,12

References

1. Promoting oral health: interventions for preventing dental caries, oral and pharyngeal cancers, and sports-related craniofacial injuries: a report on recommendations of the Task Force on Community Preventive Services. MMWR Morb Mortal Wkly Rep 2001;50(RR 21):1-13
2. Tuli T, Hachl O, Hohlrieder M, et al: Dentofacial trauma in sports accidents. Gen Dent 2002;50(3):274-279
3. Wisniewski JF: Chapter 60: Dental injuries, in: Safran MR, McKeag DB, Van Camp SP (eds): Manual of Sports Medicine. Philadelphia, Lippincott-Raven, 1998, pp 500-505
4. Honsik K: Dental injuries, in Rubin A: Sports Injuries and Emergencies: A Quick Response Manual. New York City, McGraw-Hill, 2003, pp 54-59
5. Roberts WO: Field care of the injured tooth. Phys Sportsmed 2000;28(1):101-102
6. Dale RA: Dentoalveolar trauma. Emerg Med Clin North Am 2000;18(3):521-538
7. Douglass AB, Douglass JM: Common dental emergencies. Am Fam Physician 2003;67(3):511-516
8. International Association of Dental Traumatology: Treatment Guidelines. Available at http://www.iadt-dentaltrauma.org/Trauma/dental_trauma.htm. Accessed June 24, 2004
9. Sports Dentistry Online: Sports dentistry facts. Available at http://www.sportsdentistry.com/facts.htm. Accessed June 24, 2004
10. Labella CR, Smith BW, Sigurdsson A: Effect of mouthguards on dental injuries and concussions in college basketball. Med Sci Sports Exerc 2002;34(1):41-44
11. Sports Dentistry Online: Types of athletic mouthguards. Available at www.sportsdentistry.com/mouthguards.htm. Accessed June 24, 2004
12. Newsome PR, Tran DC, Cooke MS: The role of the mouthguard in the prevention of sports-related dental injuries: a review. Int J Paediatr Dent 2001;11(6):396-404
13. McCrory P: Do mouthguards prevent concussions? Br J Sports Med 2000;35(2):81-82

Dr Honsik is a staff physician in the department of family practice and on the faculty of the Sports Medicine Fellowship program at Kaiser Permanente in Fontana, California. Address correspondence to: Kenneth A. Honsik, MD, 9985 Sierra Ave, Fontana, CA 92335; e-mail to kenneth.a.honsik@kp.org.

Disclosure information: Dr Honsik discloses no significant relationship with any manufacturer of any commercial product mentioned in this article. No drug is mentioned in this article for an unlabeled use.