Factors associated with the need for orthodontic retreatment: A retrospective cohort study

Over the past years, a rising demand for orthodontic services, along with an increasing number of individuals pursuing retreatment after undergoing prior orthodontic therapy, have been observed. Therefore, the purpose of this study is to explore various patient-related and treatment related factors influencing the need for orthodontic retreatment. The present study is retrospective, retrieving and analyzing treatment records of consecutively treated patients from a single, private orthodontic clinic. Univariate and multivariable logistic regression models were performed to explore patient-related and treatment-related factors associated with orthodontic retreatment. A total of 322 patients, with a median age of 14 years (IQR: 12, 17), females (n=190, 59%), were included. Twenty-six patients underwent repetitive orthodontic interventions, documenting an 8.1% retreatment rate. Relapse in the upper rather than the lower arch was the main motivation for most patients (n=22, 84.6%). Most cases (n=24, 92.3%) concerned patients’ esthetic dissatisfaction rather than functional issues, while 2 patients (7.7%) engaged in retreatment due to new dental conditions. Five themes were identified, regarding patients’ rationale for retreatment: 1. Minor anterior malalignment in the maxillary arch, 2. Space re-opening in the anterior region of the maxillary arch, 3. Minor anterior malalignment in the mandibular arch, 4. Space re-opening in the anterior region of the mandibular arch, 5. New dental conditions. The most frequent reason was the localized palatal displacement of one (n=5, 19.2%), or both lateral incisors (n=3, 11.5%). Based on the multivariable logistic regression model, the choice of upper retention was the only significant factor associated with retreatment (aOR:2.63; 95%CI: 1.04 to 6.66; P=0.04). A retreatment rate of 8.1% was reported. Multivariable logistic regression revealed that the only significant factor associated with orthodontic retreatment was the choice of upper retention. The odds of retreatment are 2.63 times greater when removable is preferred over fixed upper retention.