Adverse effects of orthodontic treatment: White spot lesions and root resorption

There are a number of adverse effects associated with orthodontic treatment including pain, pulpal changes, periodontal disease, and temporomandibular dysfunction. Some of these risks are not widely understood and others offer little evidence. There are two important adverse effects that will be the focus of this discussion, white spot lesions and root resorption. It is important to first understand the background including etiology, prevalence, and associated risk factors. A discussion can then be had about preventive measures to minimize these adverse affects in a treatment plan for a patient. Ultimately, orthodontists must have an appreciation and knowledge …show more content…
Root resorption is the process by which the body’s own cells eat away and dissolve tooth structure. Its exact mechanism is unclear, but its basic principle is excessive cementoclast and osteoclast activity. Most cases will not show any clinically significant resorption, but rather microscopic changes. For the majority of patients they are undetectable, but a small percentage exhibit obvious shortening of the roots. Root resorption tends to occur on the apical and lateral surfaces of roots, with minimal degree of apical resorption seen on radiographs and is associated with an average of 1-2 mm of apical root resorption during treatment. More importantly, studies have shown that root resorption doesn’t compromise the lifespan of the teeth (Hendrix I et al, …show more content…
Orthodontic forces are a prime example. The magnitude and applied force, amount of apical displacement, and method of force application all have a considerable influence. Chan and Darendeliler indicated that when assessing the direction and force of tooth movement, compressive forces cause more resorption than tensile forces (Chan E, et al 2006). Han et al also concluded that there was four times more resorption associated with intrusive forces on teeth than extrusion. This tooth movement along with lingual root torque and jiggling movement are the most influential forces causing root resorption (Han G, et al, 2005). Moreover, the duration of force application in treatment is an important risk factor. It was proposed that a two to three month pause in forces, usually done with a passive arch wire, might minimize further root resorption (Lavander et al, 1994) compared to continuous treatment. However, while some researches have found a correlation between increased treatment time and increased root resorption, others have concluded that the data was