Occlusal changes during orthognathic therapy using a completely customised lingual appliance - initial retrospective observations.

OBJECTIVE: The aim of this study was to examine the treatment outcomes, particularly the orthodontic decompensation before surgery, in patients who underwent orthognathic treatment and were treated with completely customised lingual appliances (CCLAs). METHODS: 25 patients who received combined orthognathic treatment for skeletal Class II (N = 10) or Class III (N = 15) malocclusion were retrospectively investigated. Study models from before treatment (T0), immediately before surgery (T1) and after treatment (T2), as well as digitised setup and operation models, were analysed using PAR Index and by measuring tooth pairs in contact. RESULTS: The initial PAR scores were comparable (T0: Class II: 33.30 +/- 7.85; Class III: 35.90 +/- 1.20; p = 0.539), and significant improvements were observed following treatment (T0 vs. T2: Class II: p = 0.002; Class III: p = 0.002). Excellent final PAR scores were recorded, with no statistical differences between the groups (T2: Class II: 1.60 +/- 2.80; Class III: 0.80 +/- 2.08; p = 0.246). The PAR scores for setup and operation models were 0.00 +/- 0.00 and 4.20 +/- 3.29 for Class II and 0.07 +/- 0.26 and 2.47 +/- 1.92 for Class III, respectively. No significant differences were found between setup and final model (Class II: p = 0.063; Class III: p = 0.125), but between OP and final model (Class II: p = 0.002; Class III: p = 0.001). Tooth pairs in contact demonstrated similar results. DISCUSSION: Using CCLAs in combined orthognathic treatment is efficient and leads to high-quality outcomes in Class II and III patients. Moreover, it enables excellent dental arch alignment before surgery. CLINICAL RELEVANCE: Optimal pre-surgical dental arch alignment, both before orthognathic surgery and after the completed therapy, can be achieved using CCLAs.