" A Comparative Study to Evaluate Changes of Free Gingiva Adjacent to Extraction Sites During Canines Retraction Using Different Levels of Orthodontic Forces. Journal of Hama University , [S. l.], v. 4, n. 19, 2022. Disponível em: https://journal.hama-univ.edu.sy/huj/article/view/829. Acesso em: 6 jun. 2026.