Orthodontically induced external apical root resorption in patients treated with fixed appliances vs removable aligners

• Published in: The Angle orthodontist Vol. 87; no. 1; pp. 3 - 10
• Main Authors: Iglesias-Linares, Alejandro, Sonnenberg, Boris, Solano, Beatriz, Yañez-Vico, Rosa-Maria, Solano, Enrique, Lindauer, Steven J, Flores-Mir, Carlos
• Format: Journal Article
• Language: English
• Published: United States Edward H. Angle Society of Orthodontists 01.01.2017
• Subjects: Adolescent; Adult; Child; Chromosomes, Human, Pair 2; Chromosomes, Human, Pair 4; Female; Genetic Predisposition to Disease; Genetic Variation; Genotype; Humans; Incisor - diagnostic imaging; Interleukin 1 Receptor Antagonist Protein - genetics; Interleukin-1beta - genetics; Logistic Models; Male; Malocclusion - therapy; Odds Ratio; Original; Orthodontic Appliances - classification; Orthodontics, Corrective - adverse effects; Osteopontin - genetics; Polymorphism, Single Nucleotide; Radiography, Dental - methods; Reproducibility of Results; Root Resorption - diagnostic imaging; Root Resorption - etiology; Root Resorption - genetics; Tooth Apex; Young Adult; Root resorption; Orthodontics; External apical root resorption
• ISSN: 0003-3219; 1945-7103; 1945-7103
• DOI: 10.2319/02016-101.1

Objective: To determine whether orthodontic treatment with removable aligners vs fixed orthodontic appliances is associated with a different frequency of orthodontically induced external apical root resorption (OIEARR) when genetic, radiographic, and clinical factors are accounted for. Materials and Methods: Three hundred seventy-two orthodontic patients treated with removable aligners (Invisalign) or fixed appliances were genetically screened for interleukin 1B gene ( IL1B ) ( rs1143634 ), interleukin 1 receptor antagonist gene ( IL1RN ) ( rs419598 ), and osteopontin gene ( SPP1 ) ( rs9138/rs11730582 ). Twelve clinical variables, potentially associated with OIEARR, were also considered. Subjects were divided according to the presence of radiographically determined OIEARR (>2 mm). The association between OIEARR and appliance type, and radiographic, clinical and genetic factors, was assessed using backward stepwise conditional logistic regression. Odds ratios (ORs) and 95% confidence intervals (CIs) were reported. Results: Reliability of the methods was adequate. Clinical case complexity (American Board of Orthodontics [ABO] Discrepancy Index) (OR: 1.032; 95% CI: 1.005–1.061; P = .021) and extent of incisor apical displacement in the sagittal plane (OR: 1.478; 95% CI: 1.285–1.699; P = .001) were associated with an increased OIEARR risk. After adjusting for associations between clinical/radiographic/genetic factors, there were no statistically significant differences with respect to OIEARR or type of orthodontic appliance used, whether removable aligners or fixed appliances (OR: 1.662; 95% CI: 0.945–2.924; P = .078). Only subjects homozygous for the T allele of IL1RN ( rs419598 ) were more prone to OIEARR during orthodontic treatment (OR: 3.121; CI: 1.93–5.03; P < .001). Conclusions: A similar OIEARR predisposition was identified using either removable aligners (Invisalign) or fixed appliances.