Association of hard and soft tissue factors with gingival recession in orthodontically treated patients: A retrospective study

Introduction > Orthodontic treatment is thought as a contributory factor in the development of recession. The objective of this study was to determine the factors associated with a gingival recession in patients who underwent orthodontic mechano-therapy. Material and methods > A retrospective chart review of 72 post-orthodontic cases done at the dental clinics of Aga Khan University hospital that were treated from 2009 to 2017. After evaluating dental records patients were recruited based on inclusion and exclusion criteria. Patients were divided into two groups based on the presence or absence of gingival recession on posttreatment photographs. Patients in each group were further assessed on the following factors: (1) Lower incisor inclination (IMPA). (2) Tissue thickness on the facio-lingual dimension. (3) Alveolar bone height. (4) Alveolar bone thickness. Results > The mean age of patients at the start of treatment was 16.56 +/- 5.66 years. Gingival recession was found in 40.3% of our patients while 59.7% of patients had no recession found after orthodontic treatment. Univariable logistic regression was applied for factors associated with a gingival recession following orthodontic treatment which showed that the odds ratio of gingival recession in thin gingival biotype are 14.4 times more than in thick gingival biotype. Multivariable regression analysis showed that the cases had 10.2 times more recession in thin biotype than those in the thick gingival biotype while adjusting for pre- and posttreatment alveolar heights following orthodontic treatment and with a confidence interval [95% CI = 2.69 to 38.40]. Conclusions > It was concluded from this study that 40% of patients developed gingival recession in one or more teeth during orthodontic treatment. Among different factors pre-treatment, gingival biotype of patients and male gender were the factors that were more associated with the development of gingival recession.