What Are the Risks When Orthodontically Moving Traumatized Teeth?
Dr. Michel Champagne, BA, DMD, MAGD, IBO, CDE,
Traumatic injuries to the dentition are extremely common in childhood, particularly in relation to an increase in overjet (Todd and Dodd, 1985; Bauss et al., 2008). There appears to be a greater risk when treating teeth with a history of trauma and loss of vitality and root resorption (Linge and Linge, 1991; Bauss et al., 2009). What Steps Can Be Taken to Reduce These Risks?
- If the trauma is sustained during or just prior to orthodontic treatment, a rest or observation period is recommended to allow the tooth and supporting structures to recover. The duration of this varies from 3 months for subluxated teeth or those sustaining an uncomplicated crown fracture, as in this case, to 24 months for more serious injuries such as root fractures (Atack, 1999). During active treatment, light forces should be used and excessive movement of the traumatized tooth avoided, particularly in relation to root contact with the cortical bone which has been associated with root resorption. The tooth should be vitality tested if appropriate every 3 months and radiographs repeated 6–9 months into active treatment. If a radiograph shows evidence of root resorption, a pause in active treatment is recommended for 3 months (Levander et al., 1994).
- Similarly, if teeth are traumatized during orthodontic treatment, an observation period is recommended during which active forces are suspended. If vitality is lost, necessitating root canal therapy, it is sensible practice to temporize the root canal with calcium hydroxide until the end of active orthodontics when a definitive root filling can be placed. However, for teeth that are devitalized prior to orthodontics, a definitive root filling should be placed before appliances are placed, as prolonged use of a calcium hydroxide dressing increases the risk of root fracture.