Oral Impacts of Aligners versus Fixed Self-Ligating Lingual Orthodontic Appliances

The aim of this prospective study was to compare a fixed lingual orthodontic appliance with a commonly used aligner system, focusing on oral impacts and speech disturbances, during the first 3 months of orthodontic treatment. Two groups of adults were evaluated: 21 treated with Invisalign(R) and 26 with In-Ovation L lingual brackets. Health-related quality of life questionnaires were used to assess the oral impacts, and speech samples were collected for speech evaluation by professionals. The levels of pain and painkiller intake were similar, increasing on the first day, and decreasing at 3 months. Subtle injuries on the lip and cheeks were initially reported in the aligner group. Lingual patients experienced more discomfort in swallowing and opening the mouth, tongue injuries and food residues, even at 3 months. The consonants "s " and "z " were mainly affected in both groups immediately after appliance insertion, but more often in the aligner group. These speech disturbances recovered in the following 3 months. In conclusion, both groups reported disturbances in quality-of-life measures; however, patients wearing lingual appliances experienced more disturbances, which persisted after three months. Speech disturbances were slightly more pronounced in the aligner group and recovered after three months.