Systematic Review and Meta-Analysis of the Index of Orthognathic Functional Treatment Need for Detecting Subjects with Great Need for Orthognathic Surgery

Index of Orthognathic Functional Treatment Need (IOFTN) Identifies patients with greatest need for orthognathic surgery. This systematic review looks into the available evidence on prevalence of patients with great treatment need (IOFTN 4&5) who had orthognathic surgery in previous studies. Literature search of the major electronic databases was carried out for articles published between 2014 and September 2023, looking for "Index of Orthognathic Functional Treatment Need","Orthognathic Surgery","IOFTN", "Epidemiology" and "Dentofacial Deformity". The prevalence of patients identified with IOFTN grades of 4&5 was calculated. A random-effect model was employed and the Forest and Galbraith plots were produced. The pooled prevalence estimate for subjects with IOFTN scores of 4&5 was calculated. The heterogeneity among studies was assessed with the I statistics. In total, 14 retrospective studies conducted between 2015 and 2019 in 7 countries (UK, New Zealand, Iran, Pakistan, Turkey, Malaysia, Japan) were included, reporting on 1339 orthognathic patients. The sample sizes ranged from 30 to 200. Only 7 studies reported on the subcategories of the IOFTN for grades 1, 2&3. The prevalence of orthognathic patients with IOFTN scores of 4 & 5 ranged from 79% to 100%. The heterogeneity I statistics was high (76%, random effects model) for 14 studies, but after removing 3 outlier studies reduced to zero. The pooled prevalence estimate for subjects with IOFTN scores of 4&5 was 93% (95% CI, 0.91-0.94%). According to this meta-analysis, IOFTN successfully identified 93% of patients who underwent orthognathic surgery with a great need for treatment (Grade 4 & 5). To enhance the identification of patients with well-compensated malocclusions, previous orthodontic treatment, or extreme occlusal deviations (e.g., proclination or retroclination of incisors), it would be advantageous to employ additional means alongside IOFTN for assessing orthognathic need in this group.