Evaluation of root length following treatment with clear aligners and two different fixed orthodontic appliances. A pilot study

Abstract

OBJECTIVES:The purpose of this pilot study was to evaluate the root lengths of upper incisors as an indication of the degree of orthodontically-induced apical root resorption following treatment with Smart Track® aligners and compare it with two different fixed orthodontic appliances – regular and Damon brackets – using cone-beam computerized tomography (CBCT).MATERIALS AND METHODS:The sample comprised 33 patients with class I malocclusion and 4–6 mm crowding divided in 3 groups; Group I: 11 patients treated with Smart Track® aligners, group II: 11 patients treated with Damon brackets, and group III: 11 patients with regular brackets. Maxillary incisors teeth lengths were assessed using Dolphin imaging software before and after treatment. All data were analyzed using analysis of variance and t-test.RESULTS:All groups showed statistically significant root resorption, 0–1.4 mm for clear aligners, 0.1–2.3 mm for Damon, and 0–2.5 mm for regular brackets group. However, cases treated with fixed appliance in general showed significantly higher resorption than those treated with Smart Track® aligners (P < 0.05).CONCLUSION:Orthodontically-induced root resorption, as evaluated by root length, is an inevitable drawback with different orthodontic techniques. However, the use of Smart Track® aligners showed less root resorption relative to regular fixed appliances.

Root resorption in orthodontic treatment with clear aligners: A systematic review and meta‐analysis

“…After eliminating duplicates, screening abstracts and reviewing full‐text articles, two studies were excluded after full‐text analysis because of the reasons followed: 1. no measurement of root resorption; 2. local or stage treatment (See ). As a result, 11 studies remained for qualitative analysis, whereas three studies were suitable for meta‐analysis (Figure ).…”

“…Since none of the included studies were RCTs, we used the ROBINS‐I tool to evaluate the risk of bias among the studies as one of the four levels (low, moderate, serious and critical). The overall result of the assessment showed that six studies presented a moderate risk of bias, while the other five were at serious risk of bias (Table ). The most problematic domains involved outcomes measurement, followed by deviations from intended interventions and confounding.…”

“…For this systematic review and meta‐analysis, we evaluated the incidence of ERR caused by CAT and further compared the difference and severity of ERR between CAT and FAT. Among all 11 studies included, six showed less incidence and severity of ERR in CAT compared to FAT, two described nearly the same incidence and severity, while the remaining three reported no significant ERR in CAT . Meta‐analysis revealed that ERR severity in CAT was significantly lower than in FAT.…”

“…A total of seven of the 11 studies included for a systematic review discussed some other risk factors which may influence ERR between CAT and FAT, such as sex, treatment duration, direction and amount of tooth movement, malocclusion type and degree, crowding severity, post‐treatment approximation to cortical plate, interproximal reduction, previous trauma to the teeth, use of elastic, genetic factors and so on.…”

“…Sex was considered as a risk factor for ERR only by one study of Aman et al ( P = .04 < .05), and males experienced more ERR than females, while the other studies reported no significant difference . There were also two studies avoiding this interference by balancing numbers of males and females in experimental and control groups …”